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FIELD OF THE INVENTION
The present invention relates to systems and methods for monitoring service on communications networks, and particularly to systems and methods that cause minimal disruption to the communications network traffic by using passive monitoring of network traffic data packets.
BACKGROUND OF THE INVENTION
Internet Service Providers (ISPs) are highly desirous of providing Internet Protocol (IP) services, such as Voice over IP (VoIP) and IPTV, to their customers. In order to provide these high value services, the ISP networks need to provide a high Quality of Service (QoS) even as their networks become more complex. There is, therefore, an increased demand for sophisticated monitoring tools that allow the ISPs to rapidly identify degradation in their networks performance and quickly isolate the root cause of any problems. Such tools are critical for ensuring QoS guarantees and for reducing service downtimes through timely resolution of network problems. These monitoring tools typically monitor network traffic parameters such as delay and packet loss using either active or passive measurements.
Active monitoring tools typically inject data packets into the network, or send data packets to applications, in order to obtain measurements of delays or losses.
Passive monitoring devices, in contrast, snoop on existing data-packets as they traverse the network lines as normal network traffic. Passive monitoring has the advantage that it does not increase the traffic in the network. This can be critical when a network interface or link becomes congested. During such times, injecting additional traffic into the network for active measurements may exacerbate the very problem that is being diagnosed. The disadvantages of passive measurements, however, include having less control over the measurement process as only existing network traffic is used and that the amount of data that needs to be collected can be enormous.
In order to control the costs of a passive monitoring infrastructure and the communication overhead between the monitors and the Network Operations Center (NOC), it is important to carefully select the locations at which passive monitoring probes are placed and the paths they are used to monitor. At the same time, it is important to ensure that the data collected by the monitoring probes is sufficient to provide a comprehensive and timely overview of the network's performance. In particular, it is important to provide enough passive monitoring locations that both a detection set of paths and a diagnostic set of paths can be monitored. A detection set of paths for passive monitoring of a communications network is the minimum set of paths that need to be monitored in order to detect that there is an anomaly somewhere in the network. A diagnostic set of paths is the minimum set of paths that need to be monitored in order to accurately locate and diagnose any anomaly that occurs anywhere in the network.
SUMMARY OF THE INVENTION
Briefly described, the invention provides a system and method for determining the optimal selection of paths for passively monitoring a communications network in order to detect and diagnose faults, and the optimal location for placing monitoring probes on the network to be able to monitor those paths.
In a preferred embodiment of the invention, a diagnostic set of paths, or a close approximation to it, is determined by ensuring that, for all pairs of links in the network, the diagnostic set of paths contains at least one path having only one member of that pair of links.
In a preferred embodiment of the invention, a detection set of paths that is a subset of the diagnostic set of paths is determined by ensuring that, for all the links in the communications network, there is at least one member of the detection subset of paths that contains that link.
During normal operation of the network, only the detection subset of paths needs to be monitored, reducing the amount of data that needs to be collected and reported to a network central control. Once an anomaly is detected, the system may switch to monitoring the full diagnostic set of paths so that the anomaly can be fully diagnosed.
The cost of deploying and operating the passive monitoring equipment is minimized by determining a probe location set of links in the communications network. This is the minimum set of links on which a probe needs to be placed in order to monitor the diagnostic set of paths. As the detection set of paths is a subset of the diagnostic set of paths, they will also be monitored by the probe place on the probe location set of links.
These and other features of the invention will be more fully understood by references to the following drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a schematic representation of a simple service provider network.
FIG. 2A is a schematic representation of a first case of a node in a tree topology having an edge on which a probe can be placed to distinguish an undistinguished edge pair.
FIG. 2B is a schematic representation of a second case of a node in a tree topology having an edge on which a probe can be placed to distinguish an undistinguished edge pair.
FIG. 2C is a schematic representation of a third case of a node in a tree topology having an edge on which a probe can be placed to distinguish an undistinguished edge pair.
FIG. 2D is a schematic representation of a fourth case of a node in a tree topology having an edge on which a probe can be placed to distinguish an undistinguished edge pair.
DETAILED DESCRIPTION
The present invention provides low-cost, low impact solutions for communications network monitoring infrastructures. In such systems, link level anomalies, such as excessive loss or delay of data packets traversing the network, are inferred from path-level passive measurements, i.e., network faults are monitored by observing the normal traffic flowing across the network. Such monitoring may be performed by placing and operating sophisticated monitoring tools at all nodes in the networks. This simple approach, however, is very costly. In order to reduce the cost, the method of this invention determines the optimum location of data monitoring probes on the network in order to minimize the number of data monitoring probes needed while ensuring that any anomaly that occurs anywhere in the network can be fully diagnosed.
Communications networks may be modeled as directed graphs G (V, E) having vertices V and edges E. In such a model, a node v that is an element of V may represent a network router, a switch or a gateway, while the edges of the graph may represent communications links connecting the nodes. A directed communication from a node u to a node v may then be represented by <u, v> and the corresponding undirected physical link by {u, v}. As most modern networks are full-duplex networks, for every directed edge <u i , v i >εE, there is a directed edge <v i , u i >εE.
Many Wide Area Networks (WAN) provided by, for instance, Service Providers have a general mesh topology with multiple paths between nodes in order to provide redundant paths. In enterprise environments, however, networks such as Ethernet frames are generally deployed using tree topologies, as they are simpler to implement and are more cost effective.
All Internet Protocol (IP) packets in a typical Service Provider communications network originate and terminate at edge routers that interface with customer networks or other service provider networks, and are represented in a graph model of the network by edge nodes that are a subset of nodes from the set V. In an enterprise network, edge nodes may be client hosts or application servers such as web servers or mail servers. The IP traffic between a pair of nodes traverses the network through a sequence of nodes and links dictated by the network topology and routing protocol. For instance, in a Service Provider network, the communication path between a pair of edge nodes may either be a pre-configured Multiprotocol Label Switching (MPLS) or the shortest path between nodes computed used the Open Shortest Path First (OSPF). In a tree topology network the communication path between an edge node pair is unique and traces the edges of the spanning tree.
In the graph model of the network, the set of paths between edge nodes are denoted by the set P that has members p, and where each p that is an element of P is a sequence of directed links that the path traverses. For simplicity, we assume that routing is symmetric, i.e., for every path p, there is a path {tilde over (p)} that is an element of P in the opposite direction. However, the schemes discussed in this paper are applicable even if the routing paths are asymmetric. Because passive monitoring relies on observing IP packets traversing the network to detect anomalies, paths with no traffic are not typically included in the set P.
In most commercially available routers, data packets get delayed or lost primarily due to queuing at the transmitting or outbound interfaces. Thus, a loss or delay on a directed communication link <v i , v j > can usually be traced back to the outbound interface v i . Hence, a one-to-one correspondence between the link <v i , v j > and the outbound interface v i may be assumed for the purpose of anomaly detection.
A passive monitoring infrastructure consists of a set of passive monitoring devices placed at various points in the network where they passively analyze the traffic that passes by. Various devices are available to do the observing. Most commercial routers or switches, for instance, support port mirroring in which each incoming and outgoing packet from one port of the network switch can be copied to another port where the copy of the packet can be studied. There are also hardware devices known as network taps that hook directly into a network cable and send a copy of the traffic that passes through it to one or more other networked devices. A network tap placed on a link between two nodes can measure both forward and reverse traffic on the link and is effectively measuring the incoming and outgoing traffic on the ports at the endpoints of the link. The measurements made by port mirroring and network taps are, therefore, logically equivalent. Passive monitoring devices may include the port mirrors or network taps and any associated local processing device for storing and/or forwarding the information gathered.
FIG. 1 is a schematic representation of a simple service provider network 10 , having four passive monitoring devices 12 , five links 14 and twelve possible paths 16 that can be passively monitored if they contain data. For simplicity, FIG. 1 shows only two of the paths 16 . The paths 16 may be represented as <a, v 1 , v 2 , b>, <a, v 1 , v 2 , c>. <a, v 1 , v 2 , d>, <b, v 2 , v 1 , c>, <b, v 2 , d>, <a, v 1 , c> and their inverses. In providing a passive monitoring infrastructure for the service provider network 10 , an objective is to minimize costs by deploying as few passive monitoring devices 12 as possible that will allow the accurate detection and diagnosis of all single link anomalies. In doing this placement, the assumption is that a path reports an anomaly if and only if it contains a link with an anomaly, and that each network anomaly is caused by a single link.
The anomalies to be monitored include data packet losses and data packet delays. Excessive data packet losses may be detected by, for instance, using passive monitoring devices tap 1 and tap 2 to monitor the data packets traversing the network via the path p 1 represented by <a, v1, v2, b>. At regular intervals, e.g., 1, 10 or 30 seconds, both tap 1 and tap 2 send to a central Network Operations Center (NOC) the number of packets seen on path p 1 in the most recent time interval. If the difference between the packet counts by tap 1 and tap 2 exceeds a certain pre-specified threshold even after accounting for packets still in transit along the path, then the NOC may conclude that an excessive amount of packets are being lost along some links of the path p. Alternately, the passive monitoring devices tap 1 and tap 2 may send samples of the observed packets on path p 1 to the NOC, and an inference of excessive losses on path p can be made if there is a large discrepancy in the samples from the two passive monitoring devices (also known as probes). Similarly, by associating timestamps with the data packets, it is possible to detect excessive delays along path p by keeping track at the NOC of the difference between packet timestamps averaged over an interval or for sample packets.
If an anomaly is reported on path p 1 , additional paths may be monitored in order to determine in which of the links <a, v1>,<v1, v2> or <v2, b> the anomaly has occurred. Assuming that a path reports an anomaly if and only if it contains a link with an anomaly and that the network anomaly is caused by a single link (representing an interface), it is possible to show that a set of monitored paths Q is sufficient to diagnose which is the anomalous link if, for every pair of links (e1, e2) in the set E of the graph G(V, E) representing the network, there is at least one monitored path in Q that contains exactly one of the two links.
Probe Placement
The probe placement problem solved by the method of this invention may be stated formally along the following lines. Given a directed graph, G=(V, E) and a set of paths P between edge nodes in V, let L represent the set of directed edge-pairs which cannot be distinguished by paths in P. Select the smallest number of undirected edges F on which to place probes so that every link pair in L is distinguished by some edge in F.
If each potential probe location edge F is represented by the subset LF of link pairs L that a probe on F will distinguish, then the problem becomes selecting the smallest number of subsets LF that contain all of L, i.e., the union of all selected subsets LF is L. The probe placement problem is, therefore, reduced to a classic Set Cover optimization problem.
Given a universe U and a collection of subsets S of U, a set cover is the sub-collection C of the subsets S whose union is U, i.e., a set cover is the sub-collection C that contains all the elements of U. Set Cover optimization comprises finding the smallest sub-collection C that is a set cover.
It is well-known that the Set Cover problem is Non-deterministic Polynomial-time (NP) complete, and the optimization version of set cover is NP hard.
It is also well-known that that the greedy algorithm is the best-possible polynomial time approximation algorithm for set cover under plausible complexity assumptions. The greedy algorithm for set cover chooses sets according to one rule: at each stage, choose the set which contains the largest number of uncovered elements.
For a mesh topology network, the minimum number of probe locations needed for passive monitoring of the network can, therefore, be found by the following greedy algorithm for optimal probe placement:
1. Represent the network as a directed graph G=(V, E);
2. Determine P, the set of paths between edge nodes in V;
3. Determine L, the set of directed edge-pairs which cannot be distinguished by paths in P;
4. Determine F, the set of undirected edges available to have probes placed on them;
5. Represent each member of F by the subset LF of link pairs L that a probe on F will distinguish;
6. Select F corresponding to the largest subset L F ; and
7. Repeat 2 to 6 with P now including all new paths made possible by selecting F until L=0.
For tree topology networks, an alternate algorithm can be used to find near optimal probe location. This more restricted problem can be shown to correspond to finding an optimal vertex cover. As vertex cover is known to be NP complete and, therefore, there is unlikely to be an efficient algorithm to solve it. A lazy placement algorithm embodiment of this invention can, however, be shown to be a 3-approximation of the optimal solution, i.e., if the algorithm of this invention produces placement of F probes, and the optimal solution is O probes, |F|≦3|O|.
The lazy placement algorithm proceeds bottom up in a tree topology and uses a lazy probe placement strategy, i.e., a link is only selected for placement if it distinguishes a link that cannot be distinguished further up in the tree.
TABLE 1
Lazy placement algorithm for solving the probe placement
problem in a tree topology network
Initially set the solution F(O) = { }, and the set of
undistinguished link pairs L(0) = L;
for i = 1 to |V| do
Given the set L(i − 1), make local decision for child
edges of n i ;
Add the selected edges to the solution F(i);
Remove the link pairs distinguished by F(i) from
L(i − 1) to get L(i);
end
In a preferred embodiment of the invention, the algorithm proceeds as follows:
Chose a root node;
Then proceed bottom up the tree, i.e., before processing any node, process all the node's children;
For each node, decide whether to select the child nodes for probe placement, where a child node for node n denotes the edges connecting a node n to its direct children, child(n)={c 1 , c 2 , . . . c m ). A probe on any edge in a tree topology can distinguish a directed link pair if and only if the two links are on either side of it. A child edge {n, c j } of n, therefore, can only distinguish an undistinguished link pair if one of the two directed links in the pair is in the subtree rooted at c j or on {n, c j } and the other is outside the subtree or on {n, c j }.
Furthermore, such a link pair is characterized as being a “ripe link”, i.e., a link pair that cannot be distinguished further up the tree if it satisfies one of the four cases illustrated in FIG. 2A , 2 B, 2 C or 2 D.
FIG. 2A shows the case in which one, upwardly directed link e 2 is either in the subtree rooted at the child node c j or is <c j n,> and the other upwardly directed link e 1 is on the edge connecting n to its parent.
FIG. 2B shows the case in which one, downwardly directed link e 2 is in the subtree rooted at the child node c j o and the other downwardly directed link e 1 is on the link <n, c j >.
FIG. 2C shows the case in which one, upwardly directed link e 2 is either in the subtree rooted at the child node c j or is <c j n,> and the other downwardly directed link e 1 is on the edge connecting n to another child.
FIG. 2D shows the case in which one, upwardly directed link e 1 is either in the subtree rooted at the child node c j or is <c j n,> and the other downwardly directed link e 2 is in a subtree of another child of n
In the cases represented by FIGS. 2A , 2 B and 2 C, the probe is placed on the child edge {n, c j }. In the case represented by 2 D the probe may be placed on either of the two child edges involved, {n, c j } or {n, c k }.
The lazy placement algorithm of table 1 ensures that at each step all the ripe pairs in L are distinguished. Each time an edge is added to F, the probe placement solution set, all the link pairs distinguished by it are removed from L.
If, from the remaining child edges of n, the subset of child edges which distinguish one or more undistinguished link pairs from L under the case of FIG. 2D can be represented by a set C and the set of those case of FIG. 2D link pairs from L can be represented by a set S. As each pair in S can be distinguished by two child edges, {n, c j } or {n, c k }, the problem of selecting the minimum subset of C such that all the link pairs in S are distinguished can be reduced to the Set Cover problem instance (S, C) with each element belonging to exactly two sets, which is the definition of a Vertex Cover. A Vertex Cover of an undirected graph G=(V,E) is a subset V′ of the vertices of the graph which contains at least one of the two endpoints of each edge.
The well known 2-approximation algorithm for Vertex Cover can be used to find a subset of C which distinguishes all the link pairs in S and add the subset to the solution F. The factor-2 approximation algorithm is to repeatedly take both endpoints of an edge into the vertex cover, then remove them from the graph. No better constant-factor approximation is known.
Path Selection for Anomaly Detection
The problem of path detection for anomaly detection can be stated formally as follows. Given a directed graph G=(V, E) and a set of paths P′ that can be monitored by passive probes, select the minimum subset of paths Q det such that every directed link in E belongs to at least one path in Q det . This may be termed the path cover problem.
In a mesh topology, a the path cover problem can be shown to be equivalent to the set cover problem. The greedy algorithm for set cover can, therefore, be used as a logarithmic approximation algorithm for selecting a minimum subset of paths to cover all the directed links. As described above, the greedy algorithm chooses sets according to one rule: at each stage, choose the set which contains the largest number of uncovered elements.
In a tree-topology network, a 2-approximation to the optimal path cover in the network is possible. The method consists of selecting a root, then, from each leaf node of the tree, selecting the path that comes closest to the root. Both directions of the path are then included in the solution set. If there are n leaf node vertices, clearly at least n paths are needed to completely cover all the directed links in the network. This is because each path can cover at most two directed links from those incident on the leaf nodes: the link directed from the leaf node at which the path starts to an inner node and the link directed from an inner node to the leaf node at which the path terminates. Thus at least n paths are required to cover the 2n directed links on n leaf nodes. Our solution has 2n paths and so is at least a 2-approximation. If a link is covered by a path, then from one of the leaf nodes serving as endpoints of the path, the link will be on the path from the leaf node to the root, so the link will be covered by the closest path to the root from that leaf node. Therefore, all the links in the tree will be covered by the selected paths. By including both the forward and reverse paths in the solution set, all the directed links will be covered.
Path Selection for Anomaly Diagnosis
A set of paths Q is sufficient to diagnose an anomalous link, if, for every pair of links (e 1 , e 2 ) in E, there is at least one path in Q that contains exactly one of the two links. Such a path is said to distinguish between the links e 1 and e 2 . Given a network defined as a directed graph G=(V, E) and a set of paths P′ that can be monitored by passive probes, path selection for anomaly diagnosis requires finding the minimum set of paths Q that distinguish all link pairs in E and is a subset of P′.
For mesh graph topologies, the anomaly diagnosis problem can be reduced to a set cover problem by reducing each link pair to an element and each path to the set of link pairs it distinguishes. As noted above, a path distinguishes all the links it contains from all the links it does not contain. In this reduction, p={e 1 , e 2 }εP, where e 1 , e 2 εE is reduced to the set {(e 1 , e j )|e j εE, e j {tilde over (ε)}p}∪{(e 2 , e j )|e j εE, e j {tilde over (ε)}p}. The greedy algorithm for set cover can then be used to give a logarithmic factor approximation algorithm to compute a subcollection of paths that distinguishes all the link pairs. In the greedy algorithm, sets are chosen according to one rule: at each stage, choose the set which contains the largest number of uncovered elements.
For tree topologies, there is a 12-approximation algorithm for solving the anomaly diagnosis problem. Given a tree T having n vertices, with the edges denoted by E and where P is the required set of paths, the algorithm proceeds by first obtaining a solution in each undirected edge of the tree. Once a diagnosis path set is obtained for an undirected tree network, each path in the solution can be replaced by the corresponding directed paths in both directions in order to differentiate any two directed links. A diagnosis path set should be at least a constant fraction of the number of vertices n in the tree network. Such a diagnosis path set whose size is a constant times n may be chosen as follows:
Let the optimal diagnosis path set be D o , a solution be DC and an undirected solution path set D.
First, find the undirected path cover using the 2-approximation algorithm detailed above. In this method a root is selected, then, from each leaf node of the tree, selecting the path that comes closest to the root. For the undirected case, any path cover size is at least n 1 /2, and the 2-approximation algorithm gives a path cover size of n 1 where n 1 are the leaf nodes of the tree. Call this undirected path cover set C and make D=C.
Second, for each edge e={u e , v e }, fix a path P e in the path cover that covers this edge. Also, denote by s e and t e the end points Of P e and let s e be the end closer to u e .
Thirdly, each edge e={u, v} divides the path P e into at most three segments (s e , u e ), (u e , v e ) and (v e , t e ). Among all the paths that pass through e and deviate from P e in the segment (s e , u e ), choose the one that deviates at a vertex closest to u e . Call this path P s,e . Similarly, choose P t,e . If no such path exists, or u e or v e are the endpoints, do not choose the corresponding path. Add the chosen paths to D.
The diagnostic path solution set DC can be shown to be a 12-approximation of the optimum solution D o .
Although the invention has been described in language specific to structural features and/or methodological acts, it is to be understood that the invention defined in the appended claims is not necessarily limited to the specific features or acts described. Rather, the specific features and acts are disclosed as exemplary forms of implementing the claimed invention. Modifications may readily be devised by those ordinarily skilled in the art without departing from the spirit or scope of the present invention. | A system and method for determining optimal selection of paths for passively monitoring a communications network. A diagnostic set of paths is determined by ensuring that, for all pairs of links in the network, the set contains one path having only one member of that pair. A detection subset of paths is determined by ensuring that, for all the links in the network, one member of the subset contains that link. Selecting a minimum detection and diagnostic set of paths minimizes the communication overhead imposed by monitoring. During normal operation, only the detection subset need be monitored. Once an anomaly is detected, the system may switch to monitoring the full diagnostic set. The cost of deploying and operating the passive monitoring equipment is minimized by determining the minimum set of links on which a probe needs to be placed in order to monitor the diagnostic set of paths. | 28,063 |
CROSS REFERENCES TO RELATED APPLICATIONS
This application claims priority from and is related to commonly owned U.S. Provisional Patent Application Ser. No. 61/452,450 filed Mar. 14, 2011, entitled: Apparatus for Plasma Dicing a Semi-conductor Wafer, this Provisional Patent Application incorporated by reference herein. This application is a continuation-in-part of co-pending patent application Ser. No. 13/412,119 filed on Mar. 5, 2012, entitled: Method and Apparatus for Plasma Dicing a Semi-conductor Wafer, the contents of which are incorporated herein.
FIELD OF THE INVENTION
The invention relates to the use of an apparatus for the formation of individual device chips from a semi-conductor wafer, and in particular to an apparatus which uses plasma etching to separate the wafer into individual die.
BACKGROUND
Semi-conductor devices are fabricated on substrates which are in the form of thin wafers. Silicon is commonly used as the substrate material, but other materials, such as III-V compounds (for example GaAs and InP) are also used. In some instances (for example, the manufacture of LED's) the substrate is a sapphire or silicon carbide wafer on which a thin layer of a semi-conducting material is deposited. The size of such substrates ranges from 2 inches and 3 inches up to 200 mm, 300 mm, and 450 mm diameter and many standards exist (e.g., SEMI) to describe such substrate sizes.
Plasma etching equipment is used extensively in the processing of these substrates to produce semi-conductor devices. Such equipment typically includes a vacuum chamber fitted with a high density plasma source such as Inductively Coupled Plasma (ICP) which is used to ensure high etch rates, necessary for cost-effective manufacturing. In order to remove the heat generated during the processing, the substrate is typically clamped to a cooled support. A cooling gas (typically Helium) is maintained between the substrate and the support to provide a thermal conductance path for heat removal. A mechanical clamping mechanism, in which a downward force is applied to the top side of the substrate, may be used, though this may cause contamination due to the contact between the clamp and the substrate. More frequently an Electrostatic chuck (ESC) is used to provide the clamping force.
Numerous gas chemistries appropriate to the material to be etched have been developed. These frequently employ a halogen (Fluorine, Chlorine, Bromine, or Iodine) or halogen-containing gas together with additional gases added to improve the quality of the etch (for example, etch anisotropy, mask selectivity and etch uniformity). Fluorine containing gases, such as SF 6 , F 2 or NF 3 are used to etch silicon at a high rate. In particular, a process (Bosch or time division multiplexed “TDM”) which alternates a high rate silicon etch step with a passivation step to control the etch sidewall, is commonly used to etch deep features into silicon. Chlorine and Bromine containing gases are commonly used to etch III-V materials.
Plasma etching is not limited to semiconducting substrates and devices. The technique may be applied to any substrate type where a suitable gas chemistry to etch the substrate is available. Other substrate types may include carbon containing substrates (including polymeric substrates), ceramic substrates (e.g., AlTiC and sapphire), metal substrates, and glass substrates.
To ensure consistent results, low breakage and ease of operation, robotic wafer handling is typically used in the manufacturing process. Handlers are designed to support the wafers with minimal contact, to minimize possible contamination and reduce the generation of particulates. Edge contact alone, or underside contact close to the wafer edge at only a few locations (typically within 3-6 mm of the wafer edge) is generally employed. Handling schemes, which include wafer cassettes, robotic arms and within process chamber fixtures including the wafer support and ESC, are designed to handle the standard wafer sizes as noted previously.
After fabrication on the substrate, the individual devices (die or chips) are separated from each other prior to packaging or being employed in other electronic circuitry. For many years, mechanical means have been used to separate the die from each other. Such mechanical means have included breaking the wafer along scribe lines aligned with the substrate crystal axis or by using a high speed diamond saw to saw into or through the substrate in a region (streets) between the die. More recently, lasers have been used to facilitate the scribing process.
Such mechanical wafer dicing techniques have limitations which affect the cost effectiveness of this approach. Chipping and breakage along the die edges can reduce the number of good die produced, and becomes more problematic as wafer thicknesses decrease. The area consumed by the saw bade (kerf) may be greater than 100 microns which is valuable area not useable for die production. For wafers containing small die (e.g., individual semiconductor devices with a die size of 500 microns×500 microns) this can represent a loss of greater than 20%. Further, for wafers with many small die and hence numerous streets, the dicing time is increased, and productivity decreased, since each street is cut individually. Mechanical means are also limited to separation along straight lines and the production of square or oblong shaped chips. This may not represent the underlying device topology (e.g., a high power diode is round) and so the rectilinear die format results in significant loss of useable substrate area. Laser dicing also has limitations by leaving residual material on the die surface or inducing stress into the die.
It is important to note that both sawing and laser dicing techniques are essentially serial operations. Consequently, as device sizes decrease, the time to dice the wafer increases in proportion to the total dicing street length on the wafer.
Recently plasma etching techniques have been proposed as a means of separating die and overcoming some of these limitations. After device fabrication, the substrate is masked with a suitable mask material, leaving open areas between the die. The masked substrate is then processed using a reactive-gas plasma which etches the substrate material exposed between the die. The plasma etching of the substrate may proceed partially or completely through the substrate. In the case of a partial plasma etch, the die are separated by a subsequent cleaving step, leaving the individual die separated. The technique offers a number of benefits over mechanical dicing:
1) Breakage and chipping is reduced;
2) The kerf dimensions can be reduced to well below 20 microns;
3) Processing time does not increase significantly as the number of die increases;
4) Processing time is reduced for thinner wafers; and
5) Die topology is not limited to a rectilinear format.
After device fabrication, but prior to die separation, the substrate may be thinned by mechanical grinding or similar process down to a thickness of a few hundred microns, or even less than a hundred microns.
Prior to the dicing process, the substrate is typically mounted on a dicing fixture. This fixture is typically comprised of a rigid frame that supports an adhesive membrane. The substrate to be diced is adhered to the membrane. This fixture holds the separated die for subsequent downstream operations. Most tools used for wafer dicing (saws or laser based tools) are designed to handle substrates in this configuration and a number of standard fixtures have been established; however, such fixtures are very different from the substrates which they support. Though such fixtures are optimized for use in current wafer dicing equipment, they cannot be processed in equipment which has been designed to process standard substrates. Thus, current automated plasma etching equipment is not suitable for processing substrates fixtured for dicing and it is difficult to realize the benefits that plasma etch techniques should have for die separation.
Some groups have contemplated using plasma to singulate die from wafer substrates. U.S. Pat. No. 6,642,127 describes a plasma dicing technique in which the substrate wafer is first attached to a carrier wafer via an adhesive material, before plasma processing in equipment designed for processing silicon wafers. This technique proposes adapting the form factor of the substrate to be diced to be compatible with standard wafer processing equipment. While this technique allows standard plasma equipment to dice the wafer, the proposed technique will not be compatible with standard equipment downstream of the dicing operation. Additional steps would be required to either adapt the downstream equipment or revert the substrate form factor for standard downstream equipment.
U.S. Patent Application 2010/0048001 contemplates the use of a wafer adhered to a thin membrane and supported within a frame. However, in the 2010/0048001 application, the masking process is achieved by adhering a mask material to the backside of the wafer and using a laser to define the etch streets prior to plasma processing. In contrast to standard dicing techniques which singulate the substrate from the front side, this technique introduces additional complex and expensive steps which may negate some of the advantages of plasma dicing. It also requires the additional demand of aligning the backside mask with the front side device pattern.
Therefore, what is needed is a plasma etching apparatus which can be used for dicing a semiconductor substrate into individual die and which is compatible with the established wafer dicing technique of handling a substrate mounted on tape and supported in a frame, and which is also compatible with standard front side masking techniques.
Nothing in the prior art provides the benefits attendant with the present invention.
Therefore, it is an object of the present invention to provide an improvement which overcomes the inadequacies of the prior art devices and which is a significant contribution to the advancement to the dicing of semiconductor substrates using a plasma etching apparatus.
Another object of the present invention is to provide a method for plasma dicing a substrate, the method comprising: providing a process chamber having a wall; providing a plasma source adjacent to the wall of the process chamber; providing a work piece support within the process chamber; placing a work piece onto the work piece support, said work piece having a support film, a frame and the substrate; loading the work piece onto the work piece support; applying a tensional force to the support film; clamping the work piece to the work piece support; generating a plasma using the plasma source; and etching the work piece using the generated plasma.
Yet another object of the present invention is to provide a method for plasma dicing a substrate, the method comprising: providing a process chamber having a wall; providing a plasma source adjacent to the wall of the process chamber; providing a work piece support within the process chamber; placing a work piece onto the work piece support, said work piece having a support film, a frame and the substrate; loading the work piece onto the work piece support; positioning the frame non-coplanar to the substrate on the work piece support; clamping the work piece to the work piece support; generating a plasma using the plasma source; and etching the work piece using the generated plasma.
Still yet another object of the present invention is to provide a method for plasma dicing a substrate, the method comprising: providing a process chamber having a wall; providing a plasma source adjacent to the wall of the process chamber; providing a work piece support within the process chamber; placing a work piece onto the work piece support, said work piece having a support film, a frame and the substrate; loading the work piece onto the work piece support; applying a tensional force to the support film; generating a plasma using the plasma source; and etching the work piece using the generated plasma.
Another object of the present invention is to provide a method for plasma dicing a plurality of substrates, the method comprising: providing a process chamber having a wall; providing a plasma source adjacent to the wall of the process chamber; providing a work piece support within the process chamber; placing a work piece onto the work piece support, said work piece having a support film, a frame and the plurality of substrates; loading the work piece onto the work piece support; clamping the work piece to the work piece support; generating a plasma using the plasma source; and etching the work piece using the generated plasma.
The foregoing has outlined some of the pertinent objects of the present invention. These objects should be construed to be merely illustrative of some of the more prominent features and applications of the intended invention. Many other beneficial results can be attained by applying the disclosed invention in a different manner or modifying the invention within the scope of the disclosure. Accordingly, other objects and a fuller understanding of the invention may be had by referring to the summary of the invention and the detailed description of the preferred embodiment in addition to the scope of the invention defined by the claims taken in conjunction with the accompanying drawings.
SUMMARY OF THE INVENTION
The present invention describes a plasma processing apparatus which allows for plasma dicing of a semiconductor substrate. After device fabrication and wafer thinning, the front side (circuit side) of the substrate is masked using conventional masking techniques which protects the circuit components and leaves unprotected areas between the die. The substrate is mounted on a thin tape which is supported within a rigid frame. The substrate/tape/frame assembly is transferred into a vacuum processing chamber and exposed to reactive gas plasma where the unprotected areas between the die are etched away. During this process, the frame and tape are protected from damage by the reactive gas plasma. The processing leaves the die completely separated. After etching, the substrate/tape/frame assembly is additionally exposed to plasma which removes potentially damaging residues from the substrate surface. After transfer of the substrate/tape/frame assembly out of the process chamber, the die are removed from the tape using well known techniques and are then further processed (e.g., packaged) as necessary.
Another feature of the present invention is to provide a method for plasma dicing a substrate. The substrate can have a semiconducting layer such as Silicon and/or the substrate can have a III-V layer such as GaAs. The substrate can have a protective layer such as a photoresist layer that is patterned on a circuit side of the substrate. A process chamber having a wall with a plasma source adjacent to the wall of the process chamber is provided. The plasma source can be a high density plasma source. A vacuum pump in fluid communication with the process chamber and a gas inlet in fluid communication with the process chamber can be provided. A work piece support within the process chamber is provided. A work piece is formed by placing the substrate on a carrier support. The work piece can be formed by adhering the substrate to a support film and then mounting the substrate with the support film to a frame. The support film can have a polymer layer and/or a conductive layer. The support film can be standard dicing tape. The frame can have a conductive layer and/or a metal layer. The work piece is then loaded onto the work piece support for plasma processing. An RF power source can be coupled to the work piece support to create a plasma around the work piece. A tensional force is applied to the support film. The tensional force can be applied to the frame. The tensional force can be a mechanical force, a magnetic force and/or an electrical force. The support film can be elastically deformed by the tensional force. The support film cannot be plastically deformed by the tensional force. A heat transfer fluid can be introduced between the support film and the work piece. The heat transfer fluid can be a gas such as helium. The fluid pressure can be greater than one Torr and can be less than thirty Torr. An electrostatic or mechanical chuck can be incorporated into the work piece support whereby the chuck can clamp the support film to the chuck. The clamping of the work piece can be performed after the tensional force is applied to the support film. The tensional force that is applied to the support film can be changed after the support film is clamped. The tensional force that is applied to the support film can be removed after the support film is clamped. The pressure within the process chamber can be reduced through the vacuum pump and a process gas can be introduced into the process chamber through the gas inlet. A plasma is generated through the plasma source whereby the work piece is etched through the generated plasma. A vacuum compatible transfer module can be provided that communicates with the process chamber. The work piece can be loaded onto a transfer arm in the vacuum compatible transfer module whereby the process chamber is maintained under vacuum during a transfer of the work piece from the vacuum compatible transfer module to the process chamber.
Yet another object of the present invention is to provide a method for plasma dicing a substrate. The substrate can have a semiconducting layer such as Silicon and/or the substrate can have a III-V layer such as GaAs. The substrate can have a protective layer such as a photoresist layer that is patterned on a circuit side of the substrate. A process chamber having a wall with a plasma source adjacent to the wall of the process chamber is provided. The plasma source can be a high density plasma source. A vacuum pump in fluid communication with the process chamber and a gas inlet in fluid communication with the process chamber can be provided. A work piece support within the process chamber is provided. A work piece is formed by placing the substrate on a carrier support. The work piece can be formed by adhering the substrate to a support film and then mounting the substrate with the support film to a frame. The support film can have a polymer layer and/or a conductive layer. The support film can be standard dicing tape. The frame can have a conductive layer and/or a metal layer. The work piece is then loaded onto the work piece support for plasma processing. An RF power source can be coupled to the work piece support to create a plasma around the work piece. The frame is positioned non-coplanar to the substrate on the work piece support. The support film can contact a first surface of the substrate. The support film can contact a second surface of the frame. The substrate can be positioned above the frame during the positioning step. The first surface of the substrate can be positioned non-coplanar to the second surface of the frame during the positioning step. The first surface of the substrate can be positioned above the second surface of the frame. The substrate can be supported by the work piece support and the frame can be supported by the work piece support. The substrate can be supported by the clamp and the frame can be supported by a process kit. The substrate can be supported by a clamp and the frame can be supported by a lift mechanism. The support film can be supported by the work piece support and the frame can be unsupported. An inner diameter of the frame can be greater than an outer diameter of the work piece support. The support film can be supported by the work piece support and the frame can be supported by a lift mechanism. The clamp can be an electrostatic chuck or a mechanical chuck which can be incorporated into the work piece support. The pressure within the process chamber can be reduced through the vacuum pump and a process gas can be introduced into the process chamber through the gas inlet. A plasma is generated through the plasma source whereby the work piece is etched through the generated plasma. A vacuum compatible transfer module can be provided that communicates with the process chamber. The work piece can be loaded onto a transfer arm in the vacuum compatible transfer module whereby the process chamber is maintained under vacuum during a transfer of the work piece from the vacuum compatible transfer module to the process chamber.
Still yet another object of the present invention is to provide a method for plasma dicing a substrate. The substrate can have a semiconducting layer such as Silicon and/or the substrate can have a III-V layer such as GaAs. The substrate can have a protective layer such as a photoresist layer that is patterned on a circuit side of the substrate. A process chamber having a wall with a plasma source adjacent to the wall of the process chamber is provided. The plasma source can be a high density plasma source. A vacuum pump in fluid communication with the process chamber and a gas inlet in fluid communication with the process chamber can be provided. A work piece support within the process chamber is provided. A work piece is formed by placing the substrate on a carrier support. The work piece can be formed by adhering the substrate to a support film and then mounting the substrate with the support film to a frame. The support film can have a polymer layer and/or a conductive layer. The support film can be standard dicing tape. The frame can have a conductive layer and/or a metal layer. The work piece is then loaded onto the work piece support for plasma processing. An RF power source can be coupled to the work piece support to create a plasma around the work piece. A tensional force is applied to the support film. The tensional force can be applied to the frame. The tensional force can be a mechanical force, a magnetic force and/or an electrical force. The support film can be elastically deformed by the tensional force. The support film cannot be plastically deformed by the tensional force. A heat transfer fluid can be introduced between the support film and the work piece. The heat transfer fluid can be a gas such as helium. The fluid pressure can be greater than one Torr and can be less than thirty Torr. The pressure within the process chamber can be reduced through the vacuum pump and a process gas can be introduced into the process chamber through the gas inlet. A plasma is generated through the plasma source whereby the work piece is etched through the generated plasma. A vacuum compatible transfer module can be provided that communicates with the process chamber. The work piece can be loaded onto a transfer arm in the vacuum compatible transfer module whereby the process chamber is maintained under vacuum during a transfer of the work piece from the vacuum compatible transfer module to the process chamber.
Another object of the present invention is to provide a method for plasma dicing a plurality of substrates. The plurality of substrates can have a semiconducting layer such as Silicon and/or the substrates can have a III-V layer such as GaAs. The plurality of substrates can have a protective layer such as a photoresist layer that is patterned on a circuit side of the substrate. A process chamber having a wall with a plasma source adjacent to the wall of the process chamber is provided. The plasma source can be a high density plasma source. A vacuum pump in fluid communication with the process chamber and a gas inlet in fluid communication with the process chamber can be provided. A work piece support within the process chamber is provided. A work piece is formed by placing the plurality of substrates on a carrier support. The work piece can be formed by adhering the plurality of substrates to a support film and then mounting the plurality of substrates with the support film to a frame. The support film can have a polymer layer and/or a conductive layer. The support film can be standard dicing tape. The frame can have a conductive layer and/or a metal layer. The work piece is then loaded onto the work piece support for plasma processing. An RF power source can be coupled to the work piece support to create a plasma around the work piece. A tensional force can be applied to the support film. The tensional force can be applied to the frame. The tensional force can be a mechanical force, a magnetic force and/or an electrical force. The support film can be elastically deformed by the tensional force. The support film cannot be plastically deformed by the tensional force. A heat transfer fluid can be introduced between the support film and the work piece. The heat transfer fluid can be a gas such as helium. The fluid pressure can be greater than one Torr and can be less than thirty Torr. An electrostatic or mechanical chuck can be incorporated into the work piece support whereby the chuck can clamp the support film to the chuck. The clamping of the work piece can be performed after the tensional force is applied to the support film. The tensional force that is applied to the support film can be changed after the support film is clamped. The tensional force that is applied to the support film can be removed after the support film is clamped. The pressure within the process chamber can be reduced through the vacuum pump and a process gas can be introduced into the process chamber through the gas inlet. A plasma is generated through the plasma source whereby the work piece is etched through the generated plasma. A vacuum compatible transfer module can be provided that communicates with the process chamber. The work piece can be loaded onto a transfer arm in the vacuum compatible transfer module whereby the process chamber is maintained under vacuum during a transfer of the work piece from the vacuum compatible transfer module to the process chamber.
The foregoing has outlined rather broadly the more pertinent and important features of the present invention in order that the detailed description of the invention that follows may be better understood so that the present contribution to the art can be more fully appreciated. Additional features of the invention will be described hereinafter which form the subject of the claims of the invention. It should be appreciated by those skilled in the art that the conception and the specific embodiment disclosed may be readily utilized as a basis for modifying or designing other structures for carrying out the same purposes of the present invention. It should also be realized by those skilled in the art that such equivalent constructions do not depart from the spirit and scope of the invention as set forth in the appended claims.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a top down view of a semiconductor substrate illustrating individual devices separated by streets;
FIG. 2 is a cross-sectional view of a semiconductor substrate illustrating individual devices separated by streets;
FIG. 3 is a cross-sectional view of a semiconductor substrate mounted to tape and a frame;
FIG. 4 is a cross-sectional view of a semiconductor substrate mounted to tape and a frame being etched by a plasma process;
FIG. 5 is a cross-sectional view of separated semiconductor devices mounted to tape and a frame;
FIG. 6 is a cross-sectional view of a vacuum processing chamber;
FIG. 7 is a cross-sectional of a wafer/frame in process position;
FIG. 8 is an enlarged cross-sectional view of a frame and a cover ring in a vacuum processing chamber;
FIG. 9 is a cross-sectional view of a section of the inside the chamber with the cover ring mounted to a chamber wall;
FIG. 10 is a cross-sectional view of a section of the inside the chamber with the cover ring mounted to an internal heat sink;
FIG. 11 is a top down view of a semiconductor substrate mounted to tape and a frame supported by a transfer arm;
FIG. 12 is a cross-sectional view of a semiconductor substrate mounted to tape and a frame supported by a transfer arm;
FIG. 13 is a cross-sectional view of a wafer/frame in a transfer position;
FIG. 14 is a top view of a screen;
FIG. 15 is a cross-sectional view of an electrostatic chuck;
FIG. 16 is a schematic view of a chamber in a transfer position;
FIG. 17 is a cross sectional view of the work piece and work piece support;
FIG. 18 is a cross sectional view of the work piece and work piece support;
FIG. 19 is a cross sectional view of the work piece and work piece support;
FIG. 20 is a cross sectional view of the work piece and work piece support; and
FIG. 21 is a top down view of multiple semiconductor substrates mounted to tape and a frame.
Similar reference characters refer to similar parts throughout the several views of the drawings.
DETAILED DESCRIPTION OF THE INVENTION
A typical semiconductor substrate after device fabrication is illustrated in FIG. 1 . The substrate ( 1 ) has on its surface a number of areas containing device structures ( 2 ) separated by street areas ( 3 ) in which there are no structures which allows for separation of the device structures into individual die. Although silicon is commonly used as a substrate material, other materials chosen for their particular characteristics are frequently employed. Such substrate materials include gallium arsenide and other III-V materials or non-semi-conductor substrates on which has been deposited a semi-conducting layer.
In the present invention, as is shown in a cross sectional view in FIG. 2 , the device structures ( 2 ) are then covered with a protective material ( 4 ) while the street areas ( 3 ) remain unprotected. This protective material ( 4 ) can be a photoresist, applied and patterned by well-known techniques. Some devices, as a final process step are coated with a protective dielectric layer such as silicon dioxide or PSG which is applied across the whole substrate. This can be selectively removed from the street areas ( 3 ) by patterning with photoresist and etching the dielectric material, as is well known in the industry. This leaves the device structures ( 2 ) protected by the dielectric material and the substrate ( 1 ) substantially unprotected in the street areas ( 3 ). Note that in some cases test features to check the wafer quality may be located in the street areas ( 3 ). Depending on the specific wafer fabrication process flow, these test features may or may not be protected during the wafer dicing process. Although the device pattern illustrated shows oblong die, this is not necessary, and the individual device structures ( 2 ) may be any other shape, such as hexagons, as best suits the optimum utilization of the substrate ( 1 ). It is important to note that while the previous example considers dielectric materials as the protective film, that the invention may be practiced with a wide range of protective films including semi-conductive and conductive protective films. Furthermore, the protective layer can consist of multiple materials. It is also important to note that some portion of the protective film may be an integral part of the final device structure. (e.g., a passivation dielectric, metal bonding pad, etc.)
The substrate ( 1 ) may be thinned, typically by a grinding process, which reduces the substrate thickness to a few hundred microns to as thin as approximately 30 microns or less. As is shown in FIG. 3 , the thinned substrate ( 1 ) is then adhered to a tape ( 5 ) which in turn is mounted in a rigid frame ( 6 ) to form a work piece ( 1 A). The tape ( 5 ) is typically made from a carbon-containing polymer material, and may additionally have a thin conductive layer applied to its surface. The tape ( 5 ) provides support for the thinned substrate ( 1 ) which is otherwise too fragile to handle without breakage. It should be noted that the sequence of patterning, thinning and then mounting is not critical and the steps may be adjusted to best fit the particular devices and substrate and the processing equipment used. It is important to note that while the previous example considers a work piece ( 1 A) that is comprised of mounting a substrate ( 1 ) on an adhesive tape ( 5 ) which in turn is attached to a frame ( 6 ), that the invention is not limited by the configuration of the wafer and carrier. The wafer carrier can be comprised a variety of materials. The carrier supports the substrate during the plasma dicing process. Furthermore, the wafer need not be attached to the carrier using an adhesive—any method that holds the wafer to the carrier and allows a means thermal communication of the substrate to the cathode is sufficient. (e.g. an electrostatically clamped carrier, a carrier with a mechanical clamping mechanism, etc.)
While the example above describes mounting a single substrate ( 1 ) on adhesive tape ( 5 ) that is supported by a frame ( 6 ) to form a work piece ( 1 A), the invention can also be beneficially applied to a work piece ( 1 A) that is comprised of more than one substrate ( 1 ) mounted on adhesive tape ( 5 ) which is supported by a frame ( 6 ) as is shown in FIG. 21 . The substrates ( 1 ) can be different sizes, shapes, thicknesses and/or materials. It is preferable that if the substrates are different materials that they etch in similar etch chemistries (e.g. Ge and Si both etch in fluorine-based chemistries). The substrates ( 1 ) may have different areas of exposed materials and/or different patterns. Some of the substrates ( 1 ) may be pieces of larger substrates. It is preferred that the substrates ( 1 ) be located inside the inner diameter of the support frame ( 6 ). In one embodiment, the outer diameter of the support frame ( 6 ) is smaller than the outer diameter of the work piece support. After mounting the substrate ( 1 ) with the tape ( 5 ) in the dicing frame ( 6 ), the work piece ( 1 A) is transferred into a vacuum processing chamber. Ideally, the transfer module is also under vacuum which allows the process chamber to remain at vacuum during transfer, reducing processing time and preventing exposure of the process chamber to atmosphere and possible contamination. As shown in FIG. 6 , the vacuum processing chamber ( 10 ) is equipped with a gas inlet ( 11 ), a high density plasma source ( 12 ) to generate a high density plasma, such as an Inductively Coupled Plasma (ICP), a work piece support ( 13 ) to support the work piece ( 1 A), an RF power source ( 14 ) to couple RF power to the work piece ( 1 A) through the work piece support ( 13 ) and a vacuum pump ( 15 ) for pumping gas from the processing chamber ( 10 ). During processing, the unprotected areas of substrate ( 1 ) are etched away using a reactive plasma etch process ( 7 ) as shown in FIG. 4 . This leaves the devices ( 2 ) separated into individual die ( 8 ) as shown in FIG. 5 . In another embodiment of the invention, the unprotected areas of the substrate ( 1 ) are partially etched away using a reactive plasma etch process ( 7 ). In this case, a downstream operation, such as a mechanical breaking operation, can be used to complete the die separation. These downstream methods are well known in the art.
While the previous example describes the invention using a vacuum chamber in conjunction with a high density plasma, it is also possible to etch the unprotected areas of the substrate using a wide range of plasma processes. For example, one skilled in the art can imagine variations of the invention using a low density plasma source in a vacuum chamber or even the use of plasmas at or near atmospheric pressures.
When the substrate/tape/frame assembly ( 1 A) is in the position for plasma processing, it is important that the frame ( 6 ) is protected from exposure to the plasma ( 7 ). Exposure to the plasma ( 7 ) will cause heating of the frame ( 6 ) which in turn will cause local heating of the mounting tape ( 5 ). At temperatures above approximately 100° C., the physical properties of the tape ( 5 ) and its adhesive capability may deteriorate and it will no longer adhere to the frame ( 6 ). Additionally, exposure of the frame ( 6 ) to the reactive plasma gas may cause degradation of the frame ( 6 ). Since the frame ( 6 ) is typically re-used after wafer dicing, this may limit the useful lifetime of a frame ( 6 ). Exposure of the frame ( 6 ) to the plasma ( 7 ) may also adversely affect the etch process: for example the frame material may react with the process gas, effectively reducing its concentration in the plasma which will reduce the etch rate of the substrate material, thus increasing process time. To protect the frame ( 6 ), a protective cover ring ( 20 ), as shown in FIGS. 6, 7 and 8 , is positioned above the frame ( 6 ). The cover ring ( 20 ) does not touch the frame ( 6 ) since contact with the frame ( 6 ) (which would occur during transfer into the process chamber ( 10 )) can generate undesirable particles.
In FIG. 8 , dimension (A) represents the distance between the cover ring ( 20 ) and the frame ( 6 ). This dimension can range from less than approximately 0.5 mm to greater than approximately 5 mm with an optimal value of 1.5 mm. If the distance (A) is too large, plasma ( 7 ) will contact the frame ( 6 ) and the benefits of the cover ring ( 20 ) will be lost.
It is important that the cover ring ( 20 ) is temperature controlled, otherwise its temperature will increase due to exposure to the plasma ( 7 ) and in turn heat the tape ( 5 ) and the frame ( 6 ) via radiational heating, causing degradation as noted above. For the case where the cover ring ( 20 ) is cooled, cooling of the cover ring ( 20 ) is accomplished by having it in direct contact with a cooled body, such as the process chamber wall ( 10 W) shown in FIG. 9 or a heat sink ( 30 ) located within the process chamber ( 10 ) shown in FIG. 10 . To ensure that heat is adequately removed from the cover ring ( 20 ) to the heat sink ( 30 ), the cover ring ( 20 ) should be made of a material that has good thermal conductivity. Such materials include many metals, for example Aluminum, but other thermally conductive materials, such as Aluminum Nitride and other ceramics can be used. The choice of the cover ring material is chosen to be compatible with the plasma process gases used. While Aluminum is satisfactory for Fluorine based processes, an alternate material, such as Aluminum Nitride, or the addition of a protective coating, such as Aluminum Oxide may be necessary when Chlorine based processes are used. Operation temperature of the cover ring ( 20 ) during plasma processing is typically less than 80° C. which minimizes heat radiation to the tape ( 5 ) and the frame ( 6 ) and ensures that the tape ( 5 ) maintains its mechanical integrity. Alternatively, the cover ring ( 20 ) may be temperature controlled by bringing the cover ring ( 20 ) into contact with a temperature controlled fluid. This fluid can be a liquid or gas. In the case where the cover ring ( 20 ) temperature is controlled by a fluid, the cover ring ( 20 ) may contain a number of fluid channels to facilitate heat transfer. These fluid channels can be internal to the cover ring ( 20 ), externally attached, or some combination of the two.
In one instance, the cover ring ( 20 ) can extend from the substrate diameter to the inner chamber diameter continuously. To avoid a loss in pumping conductance, which can adversely affect pressure control within the process chamber ( 10 ), a plurality of holes ( 21 ) can be added to the cover ring ( 20 ) which allows sufficient conductance of the process gas while still providing a path for heat removal from the cover ring ( 20 ). In FIGS. 9 and 10 , a plurality of holes ( 21 ) arranged in a specific geometry is shown, but the density, size, pattern and symmetry of the holes ( 21 ) can vary depending on the process chamber ( 10 ) dimensions and the pumping conductance required.
The substrate/tape/frame assembly ( 1 A) is transferred both into and out of the process chamber ( 10 ) by a transfer arm ( 40 ) that supports the frame ( 6 ) and substrate ( 1 ) so that they are maintained coplanar as shown in FIGS. 11 and 12 . The transfer arm ( 40 ) may support both the tape ( 5 ) and the frame ( 6 ) or the frame ( 6 ) alone, but it is important that the assembly ( 1 A) not be supported beneath the substrate ( 1 ) area alone because of the fragile nature of thinned substrates ( 1 ). The transfer arm ( 40 ) has an alignment fixture ( 41 ) attached to it that aligns the frame ( 6 ) in a repeatable position before being transferred into the process chamber ( 10 ). The frame ( 6 ) can also be aligned by other techniques well-known in semiconductor processing (e.g., optical alignment). The alignment can also be performed on the substrate ( 1 ) by such well-known techniques. It is important that the substrate/tape/frame assembly ( 1 A) be aligned before placement within the process chamber ( 10 ) to avoid mis-processing as explained below.
In FIG. 8 , the dimension (D) represents the distance between the outer diameter of the substrate ( 1 ) and the inner diameter of the frame ( 6 ). This may be 20 mm to 30 mm (e.g., Disco Corporation dicing frame is 250 mm for 200 mm substrates, so that the dimension (D) is nominally 25 mm). During mounting of the wafer ( 1 ) on the tape ( 5 ) within the frame ( 6 ), the deviation of wafer ( 1 ) placement may be as much as 2 mm so that dimension (E), which is the distance between the substrate ( 1 ) outer diameter and the inner diameter of the cover ring ( 20 ) can also vary from assembly to assembly by up to 2 mm. If at some point (E) is less than zero the cover ring ( 20 ) will overlay the edge of the substrate ( 1 ). This point will be shadowed and prevented from etching, which can prevent die separation and cause problems in subsequent processing steps. Alignment of the substrate/tape/frame assembly ( 1 A) prior to transfer is required to prevent such problems. Further, to additionally ensure that dimension (E) is not less than zero, the cover ring inner diameter should be greater than the diameter of the substrate ( 1 ) with a preferred diameter 5 mm greater than the substrate (e.g., 205 mm cover ring inner diameter for 200 mm substrate). Dimension (F) in FIG. 8 represents the distance from the inner diameter of the cover ring ( 20 ) to the inner diameter of the frame ( 6 ). Alignment of the frame ( 6 ) prior to transfer into the process chamber ( 10 ) ensures that (F) remains constant for the entire circumference around the substrate ( 1 ) and that any portion of tape ( 5 ) that is not contacted by the Electrostatic chuck (ESC) ( 16 ) is shadowed from the plasma ( 7 ).
When the substrate/tape/frame assembly ( 1 A) is transferred into the process chamber ( 10 ), it is placed onto the lifting mechanism ( 17 ) and removed from the transfer arm ( 40 ). The reverse process occurs during transfer of the substrate/tape/frame assembly ( 1 A) out of the process chamber ( 10 ). The lifting mechanism ( 17 ) touches the frame ( 6 ) area and provides no point contact to the substrate ( 1 ). Point contact to the substrate ( 1 ) can cause damage to the substrate ( 1 ), particularly after die separation and unloading of the substrate/tape/frame assembly ( 1 A), since the flexibility of the tape ( 5 ) would cause the die to contact each other and damage to occur. FIG. 13 shows the lifting mechanism ( 17 ) contacting the frame ( 6 ) from the underside: however the frame ( 6 ) can also be removed from the transfer arm ( 40 ) by contact with the top surface or outer diameter using a clamping device. To process the substrate ( 1 ), the frame ( 6 ), the work piece support ( 13 ), and the cover ring ( 20 ) move relative to each other. This can be accomplished by moving either the cover ring ( 20 ), the work piece support ( 13 ), or the lifting mechanism ( 17 ) or any combination of the three.
While the tape ( 5 ) in the work piece ( 1 A) is typically under some tension—there are often imperfections (ripples, etc.) in the tape that can make it difficult to clamp the work piece ( 1 A) to the substrate support ( 13 A) sufficiently for effective helium backside cooling. In order to facilitate clamping of the work piece ( 1 A) to the work piece support ( 13 ) it is beneficial to construct the work piece support assembly ( 13 A) such that the flexible tape ( 5 ) is placed under additional tension while the clamping force is applied to the work piece ( 1 A). Preferably, the additional tension is applied to the tape ( 5 ) before the clamping force is applied. Once the tape ( 5 ) has been clamped, the additional tensioning force may be changed or removed.
One way in which this additional tensioning may be accomplished to configure the work piece support assembly ( 13 A) such that the surface defined by the frame/tape interface ( 50 as shown in FIG. 17 ) is located at or below the surface defined by the substrate/tape interface ( 55 as shown in FIG. 17 ). It is preferred that the some portion of the surface 50 is at least approximately 0.1 mm below some portion of the surface 55 . Some portion of the surface 50 can be at least approximately 1 mm below the surface 55 .
In another embodiment, all of the surface 50 is below the surface 55 . In this embodiment, it is preferred that the surface 50 is at least approximately 0.1 mm below the surface 55 . The surface 50 can be at least approximately 1 mm below the surface 55 .
In the case where the tape ( 5 ) is adhered to both the bottom surface of the substrate ( 1 ) and the bottom surface of the frame ( 6 ) this may be accomplished by ensuring that the top surface of the electrostatic chuck ( 16 ) is located at or preferably above the plane defined by the lower surface of the bottom of the frame ( 6 ) as shown in FIG. 17 . In this configuration, it is preferred that the top surface of the ESC is at least 0.1 mm above the bottom surface of the bottom of the frame ( 16 ). The work piece ( 1 A) may remain in this configuration during plasma processing or the additional tension may be changed at some point in the process. This configuration is particularly beneficial when the clamping force is applied by an electrostatic chuck. The additional tensioning may be applied through a number of hardware configurations. Note that while FIG. 17 shows the tape ( 5 ) being attached to the bottom of the support frame ( 6 ) that the method may still be beneficially applied to configurations where the tape ( 5 ) is applied to the top surface of the frame ( 6 ).
The force required to apply the additional tension to the tape ( 5 ) may be applied to the frame ( 6 ). The force may be applied to the top of the frame, the bottom of the frame or both. Some portion of the force required to apply the additional tension to the tape may be derived from the weight of the frame ( 6 ).
In one configuration, the tape frame ( 6 ) is supported by the lift mechanism ( 17 ) during clamping. The top surface of the process kit ( 18 ) will be at or below the plane of the top surface of the electrostatic chuck ( 16 ). The process kit may be in contact with the tape ( 5 ) and/or the frame ( 6 ). In the cases where the process kit is not in contact with the work piece, it is preferred that the gap between the work piece ( 1 A) and the process kit ( 18 ) is less than approximately 5 mm in order to prevent plasma formation in the space between the work piece ( 1 A) and the process kit ( 18 ).
In an alternate configuration, the tape frame is not supported by the lift mechanism ( 17 ) in order to tension the tape. In this configuration the frame ( 6 ) may be supported by the process kit ( 18 ), and/or a frame support member ( 17 A) as shown in FIG. 18 .
In yet another alternate configuration, the process kit may be incorporated into and/or replaced by extending the electrostatic chuck as shown in FIG. 19 . The tape frame ( 6 ) may be supported by the electrostatic chuck where the ESC surface supporting the substrate ( 1 ) is higher than the surface supporting the tape frame ( 6 ) placing the tape ( 5 ) under additional tension. In a preferred embodiment, a portion of the surface supporting the substrate ( 1 ) is at least 0.1 mm higher than the surface supporting the tape frame ( 6 ).
In yet another configuration, the inner diameter of the tape frame ( 6 ) is larger than the outer diameter of the work piece assembly ( 13 A). In this configuration the frame may be held by the lift mechanism ( 17 ) and/or an external tape frame support ( 17 A). Alternatively, the frame may be unsupported such that the weight of the frame contributes to the tensioning force.
While the examples above describe tensioning the tape in conjunction with an electrostatic clamp, the invention may also be beneficially applied to other clamping configurations, including mechanical clamping. In another embodiment the invention may also be beneficially applied to a work piece support assembly that does not utilize a clamping mechanism.
FIG. 20 shows yet another configuration. In this configuration the flexible tape ( 5 ) is stretched across the top surface of the work piece support ( 13 A) in order to form a seal between the tape ( 5 ) and the work piece support ( 13 A). A heat transfer fluid, typically helium gas is introduced between the tape ( 5 ) and the work piece support ( 13 A). The seal between the tape ( 5 ) and the work piece support ( 13 A) needs to be sufficient to support a heat transfer fluid pressure of greater than approximately 1 Torr but less than approximately 30 Torr between the tape ( 5 ) and the work piece support ( 13 A). It is preferable that the gas pressure behind the tape does not cause a separation between the tape ( 5 ) and the work piece support ( 13 A) greater than approximately 100 microns as this would adversely affect the heat transfer between the substrate and the work piece support. It is desired that the areas of tape under the substrate ( 1 ) and tape areas of the tape that are exposed to the plasma be inside the seal created between the wafer support assembly ( 13 A) and the tape ( 5 ). The force applied to the tape frame will put at least a portion of the tape ( 5 ) under tension—possibly deforming the tape ( 5 ). It is important to limit the applied force to the tape ( 5 ) such that the tape deformation does not preclude downstream packaging operations. Ideally, tensioning the tape ( 5 ) will result in only elastic deformation—though some amount of plastic deformation may be permissible provided it does not negatively impact downstream operations. The force required to create the seal between the tape ( 5 ) and the work piece support ( 13 A) may be applied to the tape frame ( 6 ). The force can be magnetic, mechanical, electrostatic, or some combination of the three. The force may be applied to the top of the frame, the bottom of the frame or both. Alternatively, the force can be applied directly to the tape, preferably in the areas not overlapping the substrate ( 1 ) or the frame ( 6 ). In yet another embodiment, an electrostatic force may be applied to the tape underneath the area covered by the substrate ( 1 ) in order to minimize the gap between the tape ( 5 ) and the work piece support ( 13 A). During plasma processing, heat is transferred to all of the surfaces the plasma ( 7 ) touches including the substrate ( 1 ), tape ( 5 ), and frame ( 6 ). The cover ring ( 20 ) will minimize the heat transfer to areas of the tape ( 5 ) and the frame ( 6 ), but the substrate ( 1 ) must remain exposed to the plasma ( 7 ) for processing. As shown in FIG. 6 , a conductive screen ( 25 ) (e.g., made from aluminum or aluminum coated with an appropriate plasma resistant coating) can be placed between the substrate ( 1 ) and the plasma ( 7 ). This will reduce ion bombardment on the substrate ( 1 ) and thus reduce heating of the substrate ( 1 ). FIG. 14 shows the screen ( 25 ) is provided with a plurality of holes ( 26 ) which still allows neutral species from the plasma ( 7 ) to reach the substrate ( 1 ) such that the etch rate is only slightly reduced. Holes ( 27 ) allow for mounting of the screen ( 25 ) to the processing chamber ( 10 ).
Additional cooling of the substrate ( 1 ) is provided by the use of an Electrostatic chuck (ESC) ( 16 ). Such ESCs ( 16 ) are commonly used in semiconductor processing to apply downward force to the substrate ( 1 ) while a pressurized gas such as Helium is maintained between the substrate ( 1 ) and the electrode. This ensures that heat transfer can occur between the substrate ( 1 ) and the electrode, which is cooled. Typically, ESCs ( 16 ) are the same diameter or smaller than the substrate ( 1 ) to prevent unwanted exposure of the ESC ( 16 ) surface to potentially corrosive plasma gases that can decrease the lifetime of the ESC ( 16 ). With a substrate/tape/frame assembly ( 1 A), the area outside the diameter of the substrate ( 1 ) is tape ( 5 ). Using a typical ESC ( 16 ), because the cover ring ( 20 ) is larger than the diameter of the substrate ( 1 ), there would be an area of tape ( 5 ) exposed to the plasma process that is not being clamped and cooled by the ESC ( 16 ) or being shielded from the plasma ( 7 ) by the cover ring ( 20 ). Such an area of tape ( 5 ) would reach a high temperature and possibly fail. Thus, FIG. 8 shows the use of an ESC ( 16 ) that is made purposely larger than the substrate diameter so that any tape ( 5 ) which is exposed to the plasma in region (E) is also clamped and cooled. This diameter can be extended outwards to the outer diameter of the frame ( 6 ), but is preferred to be 2 mm less than the inner diameter of the frame ( 6 ).
In the case where the work piece ( 1 A) contains more than one substrate ( 1 ), it is preferred that the ESC ( 16 ) extends beyond the edge of at least one substrate ( 1 )—preferably extending beyond the edges of all substrates ( 1 ). In order to confine the cooling gas (typically helium) behind the substrates the tape ( 5 ) must form a sealing surface between the work piece support ( 1 A) and the tape ( 5 ). This sealing surface is often called a seal band. The seal band is typically slightly higher than some portion of the area of the ESC that it circumscribes. In one embodiment the sealing surface is continuous and forms a shape that circumscribes all the substrates ( 1 ). In an another embodiment, the sealing surface may be discontinuous and circumscribes at least one region. It is preferred that a portion of the sealing band overlays a portion of ESC clamping electrode(s). In a preferred embodiment, all of the sealing band overlays a clamping electrode. The substrates ( 1 ) may overlay the sealing band(s) or alternatively, the sealing band(s) may lie outside the substrate(s) ( 1 )
FIG. 8 shows a filler ring ( 18 ) that extends from the outer diameter of the ESC ( 16 ) to the lifting mechanism ( 17 ). This filler ring ( 18 ) is used to prevent the back surface of any exposed tape ( 5 ) from being contacted by the plasma ( 7 ). Although a separate filler ring ( 18 ) is shown, an extension of the ESC ( 16 ) would also prevent plasma ( 7 ) exposure to the backside of the tape ( 5 ). The filler ring ( 18 ) is typically made of a dielectric material, such as a ceramic (e.g., Aluminum Oxide) or a plastic material, (e.g., polytetrafluoroethylene (PTFE, Teflon)) selected for both its low thermal conductivity and its low electrical conductivity. Typical ESCs ( 16 ) used in semiconductor processing have a pattern of shallow features fabricated on their surface to facilitate Helium distribution or to minimize contact with the backside of a substrate ( 1 ) to reduce particle formation. Such an ESC ( 16 ) can be used for plasma dicing when a substrate ( 1 ) is separated into multiple die, providing the feature dimensions on the ESC surface are smaller than the die size. When the die size approaches and becomes smaller than the ESC feature size, the tape will now conform to the features and flex, possibly causing the die to touch each other which can cause damage. The use of a substantially coplanar ESC surface eliminates this problem. Note that though the preceding example describes an ESC that cools the substrate, for some materials (e.g. approximately 180° C. for indium containing substrates) that require a higher temperature to facilitate the plasma etch process, a higher temperature controlled ESC ( 16 ) temperature may be desirable.
A typical ESC ( 16 ) (coulombic design of FIG. 15 ) consists of one or more electrodes ( 33 ) to which a high voltage ( 19 ) is applied, separated from the work piece support ( 13 ) by a thick insulating layer ( 32 ) and separated from the material to be clamped by a thin layer of dielectric material ( 34 ). The clamping force generated by electrostatic forces increases as the thickness of this dielectric layer ( 34 ) decreases and increases as the voltage applied increases. In the present instance, when the substrate ( 1 ) is mounted on an insulating tape ( 5 ), the thickness of the tape ( 5 ) adds to the total dielectric thickness interposed between the electrode ( 33 ) and the substrate ( 1 ). This total thickness should not be determined primarily by the tape thickness, since this is likely to vary, resulting in a variable clamping performance. Rather the ESC dielectric ( 34 ) should be relatively thick (of the order of a few 100 microns) to maintain a clamping performance independent of tape thickness. A high clamping force can be achieved by operating at a high clamping voltage (up to approximately 10 kV).
During plasma processing, RF power ( 14 ) is coupled to the substrate ( 1 ) to control ion bombardment on the substrate ( 1 ) and control the etch characteristics. The frequency of this RF may vary from 100's of MHz down to a few hundred kHz. When etching a substrate material down to an insulating layer (in this instance the mounting tape), problems with the etch associated with charging of the insulating layer are well known. Such problems include localized severe undercutting at the substrate/insulator interface which is undesirable during die separation, since this affects the performance of the singulated die. As is well known in the art, such charging problems can be reduced by operating at low RF frequencies and additionally pulsing or modulating the RF power at low frequency. Since RF coupling at such low frequency is not efficient through a thick dielectric material ( 32 ), the RF coupling to the substrate ( 1 ) is preferably via the one or more ESC electrodes, for example via a coupling capacitor ( 35 ) rather than via the RF powered work piece support ( 13 ). To maintain uniform RF coupling to the substrate ( 1 ), the ESC electrode or electrodes should also be uniformly disposed behind the substrate ( 1 ). This is difficult to achieve if multiple electrodes are used, since the necessary gaps between the electrodes result in a local variation in the RF coupling which adversely affects the quality of the etch, particularly the undercutting at the substrate/tape interface. A preferred embodiment of the ESC design therefore incorporates a so called monopolar design, in which a single electrode is used to provide the clamping force. Additionally, there should be as few as possible penetrations through this electrode (for example as for pin lifts) since these penetrations will also disturb the RF coupling and degrade the etch performance.
The substrate can be processed using techniques well known in the semiconductor industry. Silicon substrates are generally processed using a Fluorine based chemistry such as SF 6 . SF 6 /O 2 chemistry is commonly used to etch Silicon because of its high rate and anisotropic profile. A disadvantage of this chemistry is its relatively low selectivity to masking material for example to photoresist which is 15-20:1. Alternatively a Timed Division Multiplex (TDM) process can be used which alternates between deposition and etching to produce highly anisotropic deep profiles. For example, an alternating process to etch Silicon uses a C 4 F 8 step to deposit polymer on all exposed surfaces of the Silicon substrate (i.e., mask surface, etch sidewalls and etch floor) and then an SF 6 step is used to selectively remove the polymer from the etch floor and then isotropically etch a small amount of silicon. The steps repeat until terminated. Such a TDM process can produce anisotropic features deep into Silicon with selectivities to the masking layer of greater than 200:1. This then makes a TDM process the desired approach for plasma separation of Silicon substrates. Note that the invention is not limited to the use of fluorine containing chemistries or a time division multiplex (TDM) process. For example, silicon substrates may also be etched with Cl, HBr or I containing chemistries as is known in the art.
For III-V substrates such as GaAs, a Chlorine based chemistry is extensively used in the semiconductor industry. In the fabrication of RF-wireless devices, thinned GaAs substrates are mounted with the device side down onto a carrier, where they are then thinned and patterned with photoresist. The GaAs is etched away to expose electrical contacts to the front side circuitry. This well-known process can also be used to separate the devices by the front side processing described in the above mentioned invention. Other semiconductor substrates and appropriate plasma processes can also be used for the separation of die in the above mentioned invention.
To further reduce the problems associated with charging at the substrate/tape interface, the process can be changed at the point at which the interface is exposed to a second process which has less tendency to undercut and is typically a lower etch rate process. The point in time at which the change takes place depends upon the substrate thickness, which is likely to vary. To compensate for this variability, the time at which the substrate/tape interface is reached is detected using an endpoint technique. Optical techniques which monitor the plasma emission are commonly used to detect endpoint and U.S. Pat. Nos. 6,982,175 and 7,101,805 describe such an endpoint technique which is appropriate to a TDM process.
After singulation of the semiconductor substrate there can be unwanted residues that exist on the devices. Aluminum is commonly used as an electrical contact for semiconductor devices and when exposed to Fluorine based plasmas a layer of AlF 3 is formed on its surface. AlF 3 is nonvolatile under normal plasma processing conditions and is not pumped away from the substrate and out of the system and remains on the surface after processing. AlF 3 on Aluminum is a common cause of failure for devices because the bonding strength of wires to the electrical contacts is greatly reduced. Thus the removal of the AlF 3 from the surface of the electrical contacts after plasma processing is important. Wet methods can be used; however, this becomes difficult because of the fragile nature of the separated die, and the possible damage to the tape causing die release. Therefore, the process can be changed to a third process while the substrate is still within the vacuum chamber, to a process designed to remove any AlF 3 formed. U.S. Pat. No. 7,150,796 describes a method for in-situ removal of AlF 3 using an Hydrogen based plasma. Likewise, an in-situ treatment can be used to remove other halogen-containing residues when other halogen-containing gases are used to etch the substrate.
While the above examples discuss the use of plasma for separating die (dicing), aspects of the invention may be useful for related applications such as substrate thinning, plasma ashing, and bond pad cleaning.
The present disclosure includes that contained in the appended claims, as well as that of the foregoing description. Although this invention has been described in its preferred form with a certain degree of particularity, it is understood that the present disclosure of the preferred form has been made only by way of example and that numerous changes in the details of construction and the combination and arrangement of parts may be resorted to without departing from the spirit and scope of the invention.
Now that the invention has been described, | The present invention provides a method for plasma dicing a substrate, the method comprising providing a process chamber having a wall; providing a plasma source adjacent to the wall of the process chamber; providing a work piece support within the process chamber; placing a work piece onto the work piece support, said work piece having a support film, a frame and the substrate; loading the work piece onto the work piece support; applying a tensional force to the support film; clamping the work piece to the work piece support; generating a plasma using the plasma source; and etching the work piece using the generated plasma. | 65,247 |
BACKGROUND INFORMATION
[0001] 1. Field
[0002] Embodiments of the disclosure relate generally to the field of packaging for pastry and baked goods and more particularly to a multidiametric case for a cupcake or similar good, the case having a relieved upper portion for clearance of frosting or topping, an aperture in the bottom allowing easy removal of the cupcake from the package and retaining elements within the case for closely contacting the cupcake for retention in the package until removal.
[0003] 2. Background
[0004] Cupcakes and similar baked goods and pastries are typically packaged in boxes containing multiple units. Baked goods such as cupcakes are quite fragile in nature and such packaging does not provide satisfactory protection for the baked goods, allowing individual cupcakes to move within the box creating distortion or damage to the soft cake and frosting. Retaining elements within the multiunit box have been previously employed as disclosed in U.S. Pat. No. 6,003,671 issued to McDonnough et al on Dec. 21, 1999. However extracting individual cupcakes is typically not easy or convenient and such packaging is not readily economically adaptable for individual cupcakes.
[0005] Individual packaging has been provided in the form of small boxes or paper wrapping which suffer many of the same issues as multiunit packaging. Certain single item packages such as that disclosed in US patent publication 2004/0251162 to McGinnis et al published on Dec. 16, 2004 have been provided, however, such packaging is overly complex and expensive to be cost effective for high quantity production and sale of baked goods.
[0006] It is therefore desirable to provide a cost effective packaging system for individual cupcakes or similar baked goods. It is additionally desirable that such a packaging system would allow easy removal of the cupcake without damage while retaining the cupcake safely within the package until removal is desired.
SUMMARY
[0007] Exemplary embodiments provide cupcake package employing a base element having a primary diameter for receiving a cupcake body and a relieving cylinder having a second diameter extending from the base element for clearance of a top contour of the cupcake. A bottom surface closes the base element and includes an aperture centrally located therein sized to accept insertion of a finger for removal of the cupcake. A cylindrical lid is closely received over the relieving cylinder to close the package. In one exemplary embodiment the base element is frustoconical.
[0008] In certain implementations, the base element further incorporates a restraint system for the cupcake. A first restraint system includes two sets of opposing apertures in the base element vertically displaced from and perpendicular to each other. A first dowel is received through the first set of apertures and extending through a cupcake body carried in the base element and a second dowel is received through the second set of apertures and extending through the cupcake body.
[0009] A second restraint system incorporates multiple pyramidal protuberances extending from an inner surface of the base element oriented with an extended point downward toward the bottom to engage the body of the cupcake.
[0010] A third restraint system uses one or more circular ridges extruded from an inner surface of the base element to engage the body of the cupcake.
[0011] The features, functions, and advantages that have been discussed can be achieved independently in various embodiments of the present invention or may be combined in yet other embodiments further details of which can be seen with reference to the following description and drawings
BRIEF DESCRIPTION OF THE DRAWINGS
[0012] FIG. 1A is a bottom angle isometric view of a general embodiment of the cupcake package of the present invention;
[0013] FIG. 1B is a side view of the embodiment of FIG. 1A ;
[0014] FIG. 1C is a bottom view of the embodiment of FIG. 1A ;
[0015] FIG. 1D is a top angle isometric view of the embodiment of FIG. 1A with the closure lid removed;
[0016] FIG. 1E is a side section view of the embodiment of FIG. 1A with a cupcake inserted in the case;
[0017] FIG. 1F is the side section view of the case with the cupcake being removed;
[0018] FIG. 2A is a bottom angle isometric view of an embodiment of the cupcake package with a first restraint structure;
[0019] FIG. 2B is a top angle isometric view of the embodiment of FIG. 2A ;
[0020] FIG. 2C is a bottom view of the embodiment of FIG. 2A ;
[0021] FIG. 2D is a top view of the embodiment of FIG. 2A showing interior details of the embodiment;
[0022] FIG. 2E is a side section view of the embodiment of FIG. 2A ;
[0023] FIG. 3A is a top isometric view of an embodiment of the cupcake package with a second restraint structure;
[0024] FIG. 3B is a top view of the embodiment of FIG. 3A ;
[0025] FIG. 3C is a side section view of the embodiment of FIG. 3A ;
[0026] FIG. 4A is a top isometric view of an embodiment of the cupcake package with a third restraint structure; and,
[0027] FIG. 4B is a side section view of the embodiment of FIG. 4A .
DETAILED DESCRIPTION
[0028] The embodiments described herein disclose a cupcake package having a multidiametric case with multiple cylindrical elements or a combination of cylinders and conical frustrums to receive the cupcake and having a bottom with an aperture for urging the cupcake from the case with a consumer's finger, a lid for closing the case, and various restraint elements within the case to maintain the cupcake in the case until removed.
[0029] As shown in FIG. 1A-1E for an exemplary embodiment, a frustoconical base element 10 of the case with a first primary diameter 11 receives the body of the cupcake (as best seen in FIG. 1E ). The shape of the base element may be a conical frustrum as shown for use with a conventional cupcake or various depths and diameters of cylindrical elements or other rotated geometric shapes defined to closely receive the baked good. The inner surface 12 of the base element frictionally engages the sides of the cupcake to assist in retaining the cupcake in the package and prevent unwanted motion in the package during handling or transport. A cylindrical top element 14 expands from the base element 10 to a second diameter 15 to allow volumetric relief within the package for frosting or top contouring of the cupcake or other baked good to be contained in the case. Further, the larger diameter of the top element simplifies the insertion of the cupcake or baked good into the case.
[0030] A lid 16 having an inner diameter sized to be closely received over the cylindrical top element 14 provides a closure for the case to protect the cupcake or baked good after insertion into the case. For the embodiment shown a filleted external surface of the lid allows for easy grasping by the consumer for removal. In alternative embodiments, a smooth cylindrical external surface or a textured surface may be employed.
[0031] A bottom surface 18 of the base element 10 incorporates an aperture 20 which is sized to accommodate insertion of a fingertip. As best seen in FIG. 1F , after removing the lid, inserting a fingertip through aperture 20 and pressing upward against the bottom 22 of the cupcake urges the cupcake body 24 from the case allowing the consumer to easily remove the cupcake for consumption.
[0032] For the exemplary embodiments, injection molded polystyrene or similar material may be employed for the case and lid providing a very low cost, mass producible product. Alternative paper, cardboard or plastic materials may be employed in alternative embodiments using standard fabrication techniques known to those skilled in the art.
[0033] To further restrain the cupcake in the case, a restraint system is employed. As shown in FIGS. 2A-2E , a first exemplary restraint system for the embodiment shown incorporates apertures 30 in the base element through which wooden or plastic toothpicks or dowels 32 are inserted, piercing the body of the cupcake. The dowel ends extend through the apertures 30 on each side of the base element thereby restraining the cupcake within the case. For the embodiment shown, two perpendicular vertically offset sets of apertures and dowels are employed. In alternative embodiments, a single aperture set and dowel may be employed or additional sets for increased security. For removal of the cupcake, the dowels are extracted from the case and the cupcake is removed by inserting a finger into the aperture 20 in the bottom 18 to urge the cupcake out of the case.
[0034] A second exemplary restraint system is shown in FIGS. 3A-3C which employs pyramidal protuberances 34 extending from the inner surface 12 of the base element 10 . Orientation of the protuberances with point 36 extending downwardly toward the bottom 18 of the base element engages and restrains the body of the cupcake when the cupcake is placed into the case and urged toward the bottom. For the embodiment shown, four pyramidal protuberances 34 are shown. In alternative embodiments one or more protuberances may be employed as required to firmly secure the cupcake or other backed good in the case. For removal of the cupcake, inserting a finger into the aperture 20 in the bottom 18 and urging the cupcake upwards with sufficient force overcomes the friction created by the indentation of the pyramidal protuberances in the body of the cupcake allowing it to be removed from the case.
[0035] Ridges 38 extruded from the inner surface 12 of the base element 10 provide a third exemplary retention system for the embodiments disclosed as shown in FIGS. 4A and 4B . For the embodiment shown, the ridges extend around an entire circumference of the inner surface and two ridges are employed. In alternative embodiments ridges extending over a portion of the circumference or a single or additional multiples of ridges are employed. A substantially circular cross section of the ridges is employed which provides sufficient resistance against the body of the cupcake to retain the cupcake in the case. However, alternative cross sections such as triangular or rectangular may be employed in alternative embodiments. As with the pyramidal protrusions, removal of the cupcake is accomplished by inserting a finger into the aperture 20 in the bottom 18 and urging the cupcake upwards with sufficient force overcomes the friction created by the indentation of the circular ridges in the body of the cupcake allowing it to be removed from the case.
[0036] Having now described various embodiments of the invention in detail as required by the patent statutes, those skilled in the art will recognize modifications and substitutions to the specific embodiments disclosed herein. Such modifications are within the scope and intent of the present invention as defined in the following claims. | A cupcake package includes a base element having a primary diameter for receiving a cupcake body and a relieving cylinder having a second diameter extending from the base element for clearance of a top contour of the cupcake. A bottom surface closes the base element and includes an aperture centrally located therein sized to accept insertion of a finger for removal of the cupcake. A cylindrical lid is closely received over the relieving cylinder to close the package. | 11,558 |
BACKGROUND OF THE INVENTION
[0001] 1. Field of the Invention
[0002] The present invention relates to ecology, and more specifically to a System and method for saving the rainforests.
[0003] 2. Background
[0004] The destruction of the rainforests in the last decades has become the biggest crime against humanity and against nature and against other entire species of animals, and also the biggest irreversible folly of the late 20 th century and beginning of the 21 st . Various statistics show that at the current rate of destruction, unless drastic changes are made right now, by the year 2020, 90-100% of all the rainforests will be irrevocably destroyed, causing damages that will take MILLIONS OF YEARS to repair, if at all. Not only that such changes have not been made so far, but the rate of destruction continually increases. Apart from the destruction of our natural resources, we are also murdering entire species, and the land itself typically becomes desert wasteland with eroded soil, where almost nothing can be grown anymore. For example, according to http://www.mongabay.com/0801.htm, “Tropical rainforests are incredibly rich ecosystems that play a fundamental role in the basic functioning of the planet, and are home to at least 50% of the world's species, making them an extensive library of biological and genetic resources. In addition, rainforests help maintain the climate by regulating atmospheric gases and stabilizing rainfall, protect against desertification, and provide numerous other ecological functions. However, these precious systems are among the most threatened on the planet. Although the precise area is disputed, each day, at least 80,000 acres (32,300 ha) of forest disappear from earth. At least another 80,000 acres (32,300 ha) of forest are degraded. Along with them, the planet loses as many as several hundred species to extinction, the vast majority of which have never been documented by science (species loss depends on the number of species on earth. If there are 30 million species, many more will disappear daily than if there are only 5 million species). As these forests disappear, more carbon is added to the atmosphere, climatic conditions are further altered, and more topsoil is lost to erosion. Worse, is that deforestation is not slowing, but increasing at an accelerated rate. During the 1980s the deforestation rate increased by 90% and deforestation in the Brazilian Amazon reached record proportions in 1995”. According to http://www.ran.org/info_center/factsheets/04b.html, the figures are much more severe: 2.4 acres (1 hectare) destroyed each second (Equivalent to two U.S. football fields), 149 acres (60 hectares) destroyed each minute, 214,000 acres (86,000 hectares) destroyed each day (An area larger than New York City), and 78 million acres (31 million hectares) destroyed each year (An area larger than Poland). In addition, according to http://www.ran.org/info_center/factsheets/03b.html (which quotes for example from Global Biodiversity Assessment , UNEP, Cambridge University Press, 1995, and from Wilson, Edward O., The Diversity of Life , Cambridge, Mass.: Harvard University Press, 1992), “The Earth's species are dying out at an alarming rate, up to 1000 times faster than their natural rate of extinction. By carefully examining fossil records and ecosystem destruction, some scientists estimate that as many as 137 [entire] species disappear from the Earth each day, which adds up to an astounding 50,000 species disappearing every year”. According to http://www.ran.org/info_center/factsheets/04b.html, rainforests are home to some 40 to 50 percent of all life forms on our planet—perhaps as many as 30 million species of plants, animals and insects. According to http://www.sumeria.net/earth/extinct.html, “More plant and animal species will go through extinction within our generation than have been lost through natural causes over the past two hundred million years. Our single human generation, that is, all people born between 1930 and 2010 will witness the complete obliteration of one third to one half of all the Earth's life forms, each and every one of them the product of more than two billion years of evolution. This is biological meltdown, and what this really means is the end to vertebrate evolution on planet Earth. Today, the tropical rain forests are disappearing more rapidly than any other bio-region, ensuring that after the age of humans, the Earth will remain a biological, if not a literal desert for eons to come. The present course of civilization points to ecocide—the death of nature. Like a run-a-way train, civilization is speeding along tracks of our own manufacture towards the stone wall of extinction. The choice is unique to this generation. Future generations will not have the chance and those that came before us did not have the vision nor the knowledge. It is up to us.”
[0005] According to http://worldforest.geo.msu.edu/rfrc/stats/wri/rank.html, the rainforests are divided among the following main countries, in descending order:
Country RainForest-Hectars 1. Brazil 291,597,000 2. Indonesia 93,827,000 3. Congo 60,437,000 4. Colombia 47,455,000 5. Peru 40,358,000 6. Papua New Guinea 29,323,000 7. Venezuela 19,602,000 8. Malaysia 16,339,000 9. Myanmar 12,094,000 10. Guyana 11,671,000 11. Suriname 9,042,000 12. India 8,246,000 13. Cameroon 8,021,000 14. French Guiana 7,993,000 15. Congo, Rep 7,667,000 16. Ecuador 7,150,000 17. Madagascar 4,507,000 18. Lao Republic 3,960,000 19. Philippines 3,728,000 20. Nicaragua 3,712,000 21. Thailand 3,082,000 22. Vietnam 2,894,000 23. Guatemala 2,542,000 24. Mexico 2,441,000 25. Panama 1,802,000 26. Belize 1,741,000 27. Cambodia 1,689,000 28. Honduras 1,286,000 29. Nigeria 1,197,000 30. Gabon 1,155,000
[0006] So, clearly, most efforts should be preferably centered in the countries that lead the list, and most of all Brazil.
[0007] According to http://www.wildkids.org.uk/rainforest.htm, almost 90% of West Africa's rain forest has already been destroyed. According to Leslie Taylor's book, Herbal Secrets of the rainforests (published in the USA by Prima Health in 1998), in 1950 15% of the Earth's land surface was covered by rainforests, but today they cover only 6% or less. She also quotes a report that shows that for example in 1996 statistics showed a 34% increase in deforestation since 1992, and a new report by a congressional committee that shows that the Amazon is vanishing at a rate of 20,000 square miles each year, which is more than 3 times the rate of 1994. According to statistics that she quotes, over 200,000 acres of rainforests are burned every day, which is, again, much more than the 80,000 acres per day estimate quoted above. That is more than 150 acres lost every minute, and 78 million acres lost every year! According to her data, this massive deforestation and destruction brings with it many ugly consequences, including but not limited to: Air and water pollution, soil erosion, malaria epidemics, the release of more CO2 into the atmosphere, decrease of Oxygen for us to breathe, more increase in the global warming, and of course the irrevocable loss of huge biodiversity and with them the loss of many potentially highly important plants and medicines. According to her book, “rain forest plants are complex chemical storehouses that contain many undiscovered biodynamic compounds with unrealized potential for use in modern medicine. We can gain access to these materials only it we study and conserve the species that contain them. Rainforests currently provide sources providing one-fourth of today's medicines, and 70% of the plants found to have anti-cancer properties are found only in the rainforest. The Rainforest and its immense undiscovered biodiversity holds the key to unlocking tomorrow's cures for devastating diseases. How many cures to devastating disease have we already lost? Two drugs obtained from a rainforest plant known as the Madagascar periwinkle, now extinct in the wild due to deforestation of the Madagascar rainforest, has increased the chances of survival for children with leukemia from 20 percent to 80 percent. Think about it—8 out of 10 children are now saved rather than 8 of 10 children dying from leukemia. How many children have been spared and how many more will continue to be spared because of this single rainforest plant? What if we failed to discover this one important plant among millions before it was extinct due to man's destruction? When our remaining rainforests are gone, the rare plants, animals will be lost forever and so will their possible cures to diseases like cancer.” In addition, she quotes Robert Goodland of the World Bank, who wrote that “Indigenous knowledge is essential for the use, identification and cataloguing of the [tropical] biota. As tribal groups disappear, their knowledge vanishes with them. The preservation of these groups is a significant economic opportunity for the [developing] nation, not a luxury.” She quotes statistics that in 1500 there were an estimated six to nine million Indigenous People inhabiting the rainforests in Brazil. The Western conquistadors left behind decimated cultures, and by 1900 there were only one million Indigenous People left in Brazil's Amazon, and today there are less than 250,000 Indigenous People of Brazil surviving this catastrophe, and still it continues. These surviving Indigenous People still demonstrate the remarkable diversity of the rainforest because they comprise 215 ethnic groups with 170 different languages. They live in 526 territories nationwide, which together comprise an area of 190 million acres, twice the size of California. About 188 million acres of this land is inside the Brazilian Amazon, in the states of Acre, Amapa, Amazonas, Para, Mato Grosso, Maranhao, Rondonia, Roraima, and Tocantins. Also, according to her book, it is estimated that 20% of the Earth's oxygen is produced in the Amazon rainforest. Many times whole acres are destroyed just to get to a few Teac or Mahogany trees, which are then used for example to build coffins in the USA, that are then just buried or burned. The main two causes for the destruction are wood logging and cattle ranching.
[0008] Just to demonstrate the amount of Biodiversity being destroyed, she gives the following statistics. For example:
[0009] One hectare (2.47 acres) of rainforest may contain over 750 types of trees and 1500 species of higher plants;
[0010] A single pond in Brazil can sustain a greater variety of fish than are found in all of Europe's rivers;
[0011] A twenty-five acre plot of rainforest in Borneo may contain over seven hundred species of trees—a number equal to the total tree diversity of North America;
[0012] A single rainforest reserve in Peru is home to more species of birds than the entire United States;
[0013] One single tree in Peru was found to harbor forty-three different species of ants—a total that approximates the entire ant species in the British Isles.
[0014] It is estimated that a single Hectare of Amazon rainforest contains about 900 tons of living plants.
[0015] According to http://www.ran.org/info_center/factsheets/04b.html, the current rate of destruction in the main relevant countries is
ORIGI- PRESENT CURRENT NAL EXTENT AMOUNT OF EXTENT OF ANNUAL OF PRIMARY DESTRUCTION FOREST FOREST (in square km COUNTRY (in sq km) COVER COVER and in % per year) Bolivia (1,098,581) 90,000 45,000 1,500 (2.1%) Brazil (8,511,960) 2,860,000 1,800,000 50,000 (2.3%) C. America (522,915) 500,000 55,000 3,300 (3.7%) Columbia (1,138,891) 700,000 180,000 6,500 (2.3%) Congo (342,000) 100,000 80,000 700 (.8%) Ecuador (270,670) 132,000 44,000 3,000 (4.0%) Indonesia (1,919,300) 1,220,000 530,000 12,000 (1.4%) Cote D'Ivoire (322,463) 160,000 4,000 2,500 (15.6%) Laos (236,800) 110,000 25,000 1,000 (1.5%) Madagascar (590,992) 62,000 10,000 2,000 (8.3%) Mexico (1,967,180) 400,000 110,000 7,000 (4.2%) Nigeria (924,000) 72,000 10,000 4,000 (14.3%) Philippines (299,400) 250,000 8,000 2,700 (5.4%) Thailand (513,517) 435,000 22,000 6,000 (8.4%)
[0016] The change must be done now, because the common wisdom so far has been that it is not urgent to take action, assuming that eventually something will be done if things get “too bad”. So unless humans realize that this wrong thinking is what has already brought us so far, the postponing of action is going to continue until the planet is irrevocably destroyed within less than one generation. Never in any time in history has any species on this planet caused so much destruction in so little time, otherwise life on this planet would have been destroyed almost completely eons ago. Various attempts have been made to motivate change, such as for example selling rainforest products that are obtained by sustainable harvesting, without destroying them, as is being done for example by Leslie Taylor, who showed that this can bring much more value per acre than destroying it, as explained below. But something was still clearly lacking, since the extent of these operations has still been very small. The main problem with this approach is that it takes time to build sufficient markets for these products and also many areas are currently inaccessible for such harvesting, so in the meantime the rest of the forest continues to be destroyed. An alternative approach has been encouraging people to donate for buying acres of the rainforests in order to save them from destruction, or even allowing people to more or less buy these acres, but many times these acres were still destroyed, because having bought it on paper still did not prevent locals from keeping destroying them. And donations clearly were not sufficient since even caring people usually only donate only relatively low amounts, whereas if a much bigger financial incentive is created, such as a real fair and lucrative investment, people will usually be ready to invest much more in it, and also much more people will want to take part in it. So clearly new approaches are needed to bring about the urgent drastic changes that are needed, by making it much more lucrative to almost anyone (for example people, and even various companies or organizations) to invest in saving the rainforests. This is clearly possible, since multinational companies that destroy the rainforests typically pay to the respective governments $2 or less for each acre that they irrevocably destroy, while taking advantage of the fact that these governments are usually suffering from heavy International debts. This is clearly ridiculous and is at the root of the folly, since clearly an indispensable natural resource of the planet is severely undersold, while its real value to the planet, in its undestroyed form, is worth many times more than that. In fact, According to an article by Peters C. M., Gentry A. H., and Mendelsohn R. O., “Valuation of an Amazonian Rainforest”, Which appeared in 1989 in Nature Magazine , Vol. 339, pp 655-656, as quoted by ran.org, the real Economic Value of One Hectare in the Peruvian Amazon is: $6,820 per year if intact forest is sustainably harvested for fruits, latex, and timber; $1,000 if clear-cut for commercial timber (not sustainably harvested), and $148 if used as cattle pasture. According to Leslie Taylor, calculations show that “if the medicinal plants, fruits, nuts, oils and other resources like rubber, chocolate and chicle (used to make chewing gums), were harvested sustainably, rainforest land has much more economic value today and more long term income and profits than if just timber were harvested or if it were burned down for cattle or farming operations. In fact, the latest statistics prove that rainforest land converted to cattle operations yields the land owner $60 per acre and if timber is harvested, the land is worth $400 per acre. However, if these renewable and sustainable resources are harvested, the land will yield the land owner $2,400 per acre. This value provides an income not only today, but year after year—for generations”.
[0017] For example in 20 years from now, after all the rainforests have been destroyed, people will be willing to pay almost any price in order to be able to go back in time and get these rainforest acres back, but it will be too late. Therefore it must be possible to motivate them to do it now instead of after it becomes too late.
SUMMARY OF THE INVENTION
[0018] The present invention tries to solve this horrible situation by creating an organization and method for motivating as many people as possible to take immediate action. This is done preferably in at least one of the following preferable ways, but preferably a combination of most or all of them:
[0019] 1. Preferably the idea of sustainable harvesting is combined with the idea of selling real acres to people. So instead of buying something only on paper, preferably an organization or multiple organizations are created, which make sure that the acres that were bought for example from the governments of the relevant countries, are indeed under supervision and protection and that preferably as many of them as possible are preferably also used for sustainable harvesting. Experience has shown that people are willing to pay even $20 or more per acre for buying land on the moon (http://moonshop.com) from a guy named Dennis Hope, whose legal rights to sell land on the moon are dubious. Yet the price that multinationals pay the governments of these countries for allowing them do destroy the rainforests is typically less than 2 dollars per acre. So it is quite possible to sell to people instead of barren acres on the moon, for a similar amount, rainforests acres that are streaming with life and are very well on the earth, together with guarding these acres and trying to make sure that these acres indeed become safe from destruction and that as many of them as possible are preferably eventually also used in a sustainable way. The acres themselves can be for example actual specific acres as defined for example by exact coordinates on a map, or for example virtual or “floating” acres, that are not bound to a single location but are more like shares in the organization that sells and takes care of these acres. Another possible variation is some combination of the above, so that for example people can choose the more general area, which can be broadly defined for example as which rainforest and/or which general part of it and/or for example some area of a few miles, and then within that area the exact acre may for example change according to various considerations or circumstances. Preferably the selling of the acres is conditional upon acceptance by the buyer of various limitations on the allowed uses of them, so that for example if the buyer himself causes destruction of the trees or animal life in the land that he bought he can for example immediately lose all rights there and/or in other rainforest acres that he bought and/or preferably have to pay a large fine. Preferably the buyers of the acres can also get for example certain royalties from the sustainable harvesting. Another possible variation is that for participating in the profits the owners have to pay for example also for additional investments needed per acre in order to run the sustainable harvesting.
[0020] 2. Another possible variation is to use time limitations in the marketing scheme, both in order to motivate people to act faster and in order to emphasize and constantly remind them that the time is indeed very limited since the destruction is going on relentlessly all the time. This can be accomplished for example by setting clear rules that increase the price per acre according to the percent of rainforests remaining all the time. However, this implementation has the dangerous disadvantage that it might encourage some unscrupulous people or organization to buy up rainforest land and then continue to encourage the destruction in other parts of the rainforests on purpose in order to drive up the price of the rainforest land that they already bought. A better variation is to define a constant time scheme that is independent of the actual rate of destruction, such as for example determine that the price per acre will go up each month for example by 1% (or any other reasonable percent) or for example by a constant sum, such as for example 50 cents each month, etc., regardless of the rate of destruction.
[0021] 3. Another possible variation is to give reductions in price according to quantity, so that the more acres someone buys, the less he has to pay per acre.
[0022] 4. Another possible variation is to use various forms of “viral” or multilevel marketing, so that people have a direct incentive for telling more friends about this and convincing them to buy additional land, which is something missing for example from the dubious moon-acres marketing. So for example if a real rainforests acre costs for example $30 to a simple buyer, preferably he can get back for example $5 for each additional friend that he convinces to also buy an acre. Preferably this can be repeated for any amount of acres, or for example the more acres sold, the bigger the reduction to the buyer and preferably also the bigger the percent of bonus for the person who brought that buyer, so that for example if someone buys for example 100 acres, he has to pay only for example $22 per acre, and the person who brought him preferably gets a commission of for example $6 per acre sold through him. Another possible variation is to repeat this structure exponentially so that for example each person gets some commission (preferably a reduced one) also for each sale brought about by someone which he/she brought into the organization, so that for example if person A sells an acre to person B, he gets for example $5 commission for each acre sold, and if then person B sells an acre to person C, person A still gets for example a commission of $0.5 for this sale. Preferably, various limitations are added in order to limit the costs of this to the organization, so that for example this chain is limited to a certain length and/or to a certain maximum cumulative commission allowed and/or for example to a certain amount of deals and/or of acres sold. Another possible variation for adding even more to the safety of the people getting involved is adding the improvement that users can for example preferably have an option of delayed payment, so that they can for example buy the acres temporarily without paying for them and then have a grace period of for example 1-3 months for actually paying and keeping the acres, so that in the meantime they can see if they can sufficiently continue selling acres to others and getting those others to preferably sell to additional others, so that before the end of the grace period they can already have a good estimate if it was worth it, even before they have to spend a single real dollar. Another possible variation is that this does not have to be an all-or-nothing decision, so that the buyer can for example decide to keep only some of the acres by paying for them, and then the others in which he didn't finalize the sale go back to the available pool. Also, preferably the participants don't have to buy acres in order to sell these acres or other acres to others, but can act as agents even without buying any acres themselves at all, thus still getting commissions for each sale. This way for example users can buy many more acres than they could normally afford, by simply selling more acres to others and encouraging them to help sell acres too, so that they can finance their buying by their commissions, and in addition, preferably through trial the period, they can know in advance more or less how their balance is going to look like before even having to spend any real money for finalizing their buying of acres. To the best of my knowledge this type of “safe testing period” has never been used in any multilevel marketing scheme in any area in the current state of the art. Of course, in this variation, preferably all commissions are also contingent, depending on the further buyer to actually make the deal real. In addition to this, preferably this structure can be traced for example on the Internet so that each user can know at all times how many “agents” are working in the logical tree below him at any time and/or preferably how many acres each of them sold and preferably what his credit status is at any time, etc.
[0023] 5. Another possible variation is to issue for example, preferably in addition, at least once in a while also public stocks of the organization itself, so that more funds can be gained for supporting its causes and especially for buying as many acres as possible in advance.
[0024] Of course, various combinations of the above and other variations can also be used, both within the solutions and across them.
[0025] Another problem is how to make sure that the rainforest lands bought indeed become protected, preferably in an efficient and cost-effective way, and how to start indeed sustainable harvesting in these lands. Of course, sustainable harvesting cannot be done at once in all the areas, and is also limited for example by market forces, such as for example the current world demand for a certain product, and the lack of accessibility to many areas. Therefore, preferably the organization does not guarantee that each acre will be used for producing anything but only for example that it will do its best to implement it in as many acres as possible. Therefore, when it comes to the sustainable harvesting, preferably each buyer becomes a partner in the total income of the organization from the sustainable harvesting, preferably proportionally to the number of acres that he owns. Various preferable solutions are possible for guarding the bought acres against destruction:
[0026] 1. Making deals with the respective governments so that by getting the much higher prices per acre than the $2 or less that they get for allowing to destroy each acre, they will also be obliged to guard at least the bought areas for example by Extended police forces and/or by parts of the army, and/or for example by other special forces designated for this. Another possible variation is that preferably the governments have to agree in return to change the laws if needed so that destroying rainforest lands and/or especially any of the lands that were already paid for, becomes punishable by preferably huge fines and preferably also imprisonments, so that even without intensive guard all the time, the motivation for destroying rainforests becomes much lower.
[0027] 2. Making deals with the local populations and/or with indigenous natives, wherein they are paid for example a certain amount per month to guard large areas or at least to issue a warning immediately as soon as they spot dangerous or suspect activities, etc. However, this creates additional monthly expenses, so if used, it is preferably combined with at least some sustainable harvesting which can thus help cover these monthly expenses. In this case, preferably the same locals used for guarding the areas are preferably also employed for the sustainable harvesting. In fact, letting local people work for the sustainable harvesting and preferably also get additional revenues from the profits from the sustainable harvesting is very preferable, since otherwise they themselves take part in the destruction. Another possible variation is to use, in addition or instead, hi-tech surveillance, such as for example through preferably low orbiting satellites, and/or for example zeppelins and/or balloons, that preferably report, preferably in real time, the conditions of the entire rainforests or at least large parts of them, so that any suspect or dangerous events can preferably be instantly spotted and appropriate action can be taken.
[0028] 3. Creating different sources for fuel and for wood than rainforests, thus supplying the demand and removing much of the incentives that currently exist for continuing to destroy the rainforests. This can be done for example by encouraging and promoting the use of fast-growing plants that can easily replace wood, such as for example Kanef and/or industrial Hemp, which make in fact better wood fibers than ordinary trees and grow much faster. Hemp can grow for example to the size of a full tree within a few months, and has longer and better fibers than normal wood, so it can be used for example for creating better logs and/or fiber-boards, and can be also used for example for extracting Biomass fuel, for example in the form of Methylic Alcohol, which is much less polluting than current Gasoline, and is of course much more sustainable. Some of these plants can even be planted in rainforests lands that were already destroyed and deserted, since these are very resilient plants that can grow even is such destroyed places.
[0029] 4. Preferably, in addition to the above, Class Action suits are filed, preferably against the multi-national organizations who destroy rainforests and/or against governments that allow it, on account of crimes against humanity, which are therefore relevant to the entire 6 billion humans that inhabit this planet and also to their progeny, who will all suffer the consequences of these acts.
[0030] Of course, various combinations of the above and other variations can also be used, both within the solutions and across them.
[0031] Important Clarification and Glossary:
[0032] Throughout the patent when variations or various solutions are mentioned, it is also possible to use various combinations of these variations or of elements in them, and when combinations are used, it is also possible to use at least some elements in them separately or in other combinations. These variations are preferably in different embodiments. In other words: certain features of the invention, which are described in the context of separate embodiments, may also be provided in combination in a single embodiment. Conversely, various features of the invention, which are described in the context of a single embodiment, may also be provided separately or in any suitable subcombination. “User” or “users” or “buyer” or buyers” as used throughout the patent, including the claims, can interchangeably be either single or plural, and can refer to both sexes even when words such as for example “he” or “she” or “his” or “her” are used. Although the land units have been described for convenience mainly in acres, this is just an example, so thought the patent, including the claims, “acre” can mean an actual acre, or any other convenient units or sub-units of area. Throughout the patent, including the claims, the words “organization” or “organizations” can interchangeably mean either single or plural organizations.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0033] All of the descriptions in this and other sections are intended to be illustrative examples and not limiting.
[0034] The above preferable solutions are hereby described in more detail:
[0035] 1. Preferably the idea of sustainable harvesting is combined with the idea of selling real acres to people. So instead of buying something only on paper, preferably an organization or multiple organizations are created, which make sure that the acres that were bought for example from the governments of the relevant countries, are indeed under supervision and protection and that preferably as many of them as possible are preferably also used for sustainable harvesting. Experience has shown that people are willing to pay even $20 or more per acre for buying land on the moon (http://moonshop.com) from a guy named Dennis Hope, whose legal rights to sell land on the moon are dubious. Yet the price that multinationals pay the governments of these countries for allowing them do destroy the rainforests is typically less than 2 dollars per acre. So it is quite possible to sell to people instead of barren acres on the moon, for a similar amount, rainforests acres that are streaming with life and are very well on the earth, together with guarding these areas and trying to make sure that these acres (and preferably also as many other unsold acres as possible) indeed become safe from destruction and that as many of them as possible are preferably eventually also used in a sustainable way. The acres themselves can be for example actual specific acres as defined for example by exact coordinates on a map, or for example virtual or “floating” acres, that are not bound to a single location but are more like shares in the organization that sells and takes care of these acres. Another possible variation is some combination of the above, so that for example people can choose the more general area, which can be broadly defined for example as which rainforest and/or which general part of it and/or for example some area of a few miles, and then within that area the exact acre may for example change according to various considerations or circumstances. Preferably users can also name acres after their name or after names of others and are preferably encouraged also for example to buy them as gifts to friends and relatives. Preferably users can also see their bought acres or at least their general area or areas, for example by live feed on the Internet, for example through satellites and/or balloons and/or zeppelins. Preferably there are various zoom functions available and the users can focus on various areas, and preferably interactive maps are available that show in real time for example areas already bought, areas not bought yet, areas that are already destroyed, areas that are currently being destroyed, etc. This is preferably done by using multiple, preferably wide angle, cameras on preferably multiple zeppelins and/or balloons and/or satellites, and/or allowing the users also to give remotely various commands to at least some of said cameras, such as for example changing angle and/or focus. Another possible variation is that various cameras for example constantly rotate and/or change focus and the users can view various areas based on the recently acquired relevant images. Preferably people can see on the Internet all the time the current status of the amount of acres bought and sold by the organization and also preferably a constant update on the rates and areas of continuing destruction. Another possible variation is that people can also see for example the lists of all those who already bought acres and/or the amounts they bought, except for example in case certain buyers explicitly request to remain anonymous. In case that any of relevant governments do not agree for example to the acres becoming fully owned by foreign citizens, preferably the selling is done so that at least some ownership rights remain also in local hands or in the hands of these governments. For example in Brazil and in Peru foreign citizens are not allowed by law to buy land, so at least for the countries that have these limitations, preferably instead of the acres themselves, for example what is sold is only the sustainable harvesting rights for example for the next 10 years or next 100 years, etc. Another possible variation is that what is sold is for example preferably a lease—for example for the next 100 years, while officially the land still remains for example under the ownership of the government or for example under the ownership of a branch of the organization that is locally incorporated, so that for example the organization really buys the acres but the clients only lease them for a time that to a human seems like forever but for Nature is nothing. Another possible variation is that the buyers just buy shares in the organization, except that the organization is preferably compelled to buy for each acre paid for at least one real acre of rainforests, so that the buyers know that they paid for a real acre, thus both saving the rainforests, and getting the right to really own such an acre (except of course for the limitation that they may use it only according to the limitations set by the organization). Therefore, preferably the selling of the acres is conditional upon acceptance by the buyer of various limitations on the allowed uses of them, so that for example if the buyer himself causes destruction of the trees or animal life in the land that he bought he can for example immediately lose all right there and/or in other acres that he bought and/or preferably have to pay a large fine. Preferably the buyers of the acres can also get for example certain royalties from the sustainable harvesting. Another possible variation is that for participating in the profits of the sustainable harvesting the owners have to pay for example also for additional investments needed per acre in order to run the sustainable harvesting. The entire scheme is based on the assumption that if the governments of the rainforest areas are paid considerably more per acre by the organization than what they get for example from multinational organizations that pay for example $2 for each acre that they irrevocably destroy, then they will prefer to sell to the organization. Preferably they will even more prefer to sell to the organization, when they take into consideration that this way in fact they are saving the rainforests instead of destroying them, and during the process get much more compensation for them. Preferably the governments get also, in addition, for example some percent of the revenues from the sustainable harvesting, for example in the form of taxes and/or additional commission. Preferably the organization itself is a non-profit organization, so that most or all of the profits go back to further helping to save the rainforests (except for example money needed for advertising, Public Relations, etc.), and thus also people will have more sympathy and trust towards it. Preferably the contract that the buyers have to agree to includes also acknowledging also the rights of the indigenous natives who populate these areas, such as for example the Amazonian Indian, so that they also become part of the process to the extent possible. Of course the acres are preferably not purchased one by one but in preferably large bunches, which makes overhead and paperwork costs much cheaper. This can be done by either the organization buying each time a sufficiently large bunch in advance, and/or for example accumulating orders together for example each month or more (or any other convenient time period) and only then doing the actual purchase as one transaction. This way all the licensing fees and other related expenses are also done preferably in large bunches, preferably in advance, even for example for acres not bought yet, which means that the overhead cost per single acre should become negligible. Similarly, for example harvesting experts are used preferably for determining the harvesting recommendation for large areas each time and not on an individual acre basis. Preferably, the best and largest rainforest lands owned by the government are located and bought from the government at a fixed price and fixed procedure for example after reaching an agreement that will be used also for all later purchases. Of course, preferably the buyers can share also other potential revenues from the sold and/or leased areas, such as for example tourism, revenues from displaying live feeds, etc. Another possible variation is preferably planting and growing at least in some areas various additional appropriate plants and/or trees that can preferably be used for food in these areas in a way that doesn't damage the existing trees, plants, animals, and/or soil (These are preferably indigenous plants that already exist in the area. However, if this is done, it must be done carefully so as not to disrupt ecological balances).
[0036] 2. Another possible variation is to use time limitations in the marketing scheme, both in order to motivate people to act faster and in order to emphasize and constantly remind them that the time is indeed very limited since the destruction is going on relentlessly all the time. This can be accomplished for example by setting clear rules that increase the price per acre according to the percent of rainforests remaining all the time. However, this implementation has the dangerous disadvantage that it might encourage some unscrupulous people or organization to buy up rainforest land and then continue to encourage the destruction in other parts of the rainforests on purpose in order to drive up the price of the rainforest land that they already bought. A better variation is to define a constant time scheme that is independent of the actual rate of destruction, such as for example determine that the price per acre will go up each month for example by 1% (or any other reasonable percent) or for example by a constant sum, such as for example 50 cents each month, etc., regardless of the rate of destruction.
[0037] 3. Another possible variation is to give reductions in price according to quantity, so that the more acres someone buys, the less he has to pay per acre.
[0038] 4. Another possible variation is to use various forms of “viral” or multilevel marketing, so that people have a direct incentive for telling more friends about this and convincing them to buy additional land, which is something missing for example from the dubious moon-acres marketing. So for example if a real rainforests acre costs for example $30 to a simple buyer, preferably he can get back for example $5 for each additional friend that he convinces to also buy an acre. Preferably this can be repeated for any amount of acres, or for example the more acres sold, the bigger the reduction to the buyer and preferably also the bigger the percent of bonus for the person who brought that buyer, so that for example if someone buys for example 100 acres, he has to pay only for example $22 per acre, and the person who brought him preferably gets a commission of for example $6 per acre sold through him. Another possible variation is to repeat this structure exponentially so that for example each person gets some commission (preferably a reduced one) also for each sale brought about by someone which he/she brought into the organization, so that for example if person A sells an acre to person B, he gets for example $5 commission for each acre sold, and if then person B sells an acre to person C, person A still gets for example a commission of $0.5 for this sale. Preferably, various limitations are added in order to limit the costs of this to the organization, so that for example this chain is limited to a certain length (for example up to N levels in the tree) and/or to a certain maximum cumulative commission allowed and/or for example to a certain amount of deals and/or of acres sold. This multilevel marketing is of course similar to various Pyramid schemes, except that in this case there is a very real product, and also it is for a very good cause. However, there are also additional Improvements, as explained below: Another problem with normal “Pyramid Schemes” is that many times people are afraid to lose money if they are not successful in selling the product forward, such as for example in the case of products like “Lifestiles”, in which each participant is required to spend an expensive sum just to “get into the game”. However, the real danger and the real test for the legitimacy of any Pyramid scheme depends clearly on the nature of the “product” sold, since if the product is not worth the money paid for it, than obviously the only profit can come from selling it in time to a greater “sucker” who is willing to pay more for it, until certainly there will come a time where the buyers are no longer able to sell it to other buyers, and then the entire “Pyramid” crushes. An example of this is for example during a stock market bubble, such as happened for example with the NASDAQ before the crash that began at the end of March 2000, when people bought stocks clearly many times above their real value, but still thought they will be able to get out in time by selling it to someone else who will still be willing to pay more in the hope of also making some “quick buck” and exiting. On the other hand, when the value of the product is real, and preferably no unregulated speculation is allowed, then clearly no crash at the end is expected, since even the last buyers should have no problem. Therefore, in order to prevent later speculation and/or to prevent circumventing the purposes of the organization, preferably when anyone buys one or more acres the selling contract itself is conditional so that he may not resell his rainforest acres or other rainforest acres except to persons who also agree to the same terms, and may sell it only according to the prices allowed by the organization at that time. Another possible variation for adding even more to the safety of the people getting involved is adding the improvement that users can for example preferably have an option of delayed payment, so that they can for example buy the acres temporarily without paying for them and then have a grace period of for example 1-3 months (or any other convenient or reasonable period) for actually paying and keeping the acres, so that in the meantime they can see if they can sufficiently continue selling acres to others and getting those others to preferably sell to additional others, so that before the end of the grace period they can already have a good estimate of how many acres they can afford or if it was worth it, even before they have to spend a single real dollar. (The same grace period is preferably automatically applicable at all levels of the tree, so that the moment someone agrees to buy he/she preferably has automatically the same standard grace period to decide. Another possible variation is that the buyer is limited to the same grace period of the person that sells to him/her, so that for example if the seller has only part of his grace period left for given acres, the people that buy through him are preferably limited in those acres to the same remaining part of the grace period that the seller has). Another possible variation is that the grace period is for example dependent on the amount of acres involved in each deal. Another possible variation is that preferably users can buy acres from the organization at cheaper rates depending on the amount of acres that they have already bought and/or sold so far. Another possible variation is that this does not have to be an all-or-nothing decision, so that the buyer can for example decide to keep only some of the acres by paying for them, and then the others in which he didn't finalize the sale preferably go back to the available pool. Another possible variation is that at least some small deposit needs to be made in advance on account for each acre bought, which is nonrefundable if the buyer cancels. Also, unlike Lifestiles for example, preferably the participants don't have to buy acres in order to sell these acres or other acres to others, but can act as agents even without buying any acres themselves at all, thus still getting preferably the same or different commissions for each sale. This way for example users can buy many more acres than they could normally afford, by simply selling more acres to others and encouraging them to help sell acres too, so that they can finance their buying by their commissions, and in addition, preferably through the trial period, they can know in advance more or less how their balance is going to look like before even having to spend real money for finalizing their buying of acres. To the best of my knowledge this type of “safe testing period” has never been used in any multilevel marketing scheme in any area in the current state of the art. Of course, in this variation, preferably all commissions are also contingent, depending on the further buyer to actually make the deal real. Another possible variation is that the more acres each person owns, the higher commission he can get for direct and/or indirect sales. In addition to this, preferably this structure can be traced by the users for example on the Internet so that each user can know at all times how many “agents” are working in the logical tree below him/her at any time and/or preferably how many acres each of them sold and preferably what his credit status is at any time, etc. A similar scheme to this (with any one or more of the above variations) can be used for example also for marketing any other real product for example on the Internet, and also for example for marketing stocks or shares for example in any Internet company, even without payment in advance, so that for example the users “play” with accumulating credit points, which can later become for example options that can be converted into real property when the company becomes of real value and thus the user can then have the choice of for example paying some real money and converting his options into real shares.
[0039] 5. Another possible variation is to issue for example, preferably in addition, at least once in a while also public stocks of the organization itself, so that more funds can be gained for supporting its causes.
[0040] Of course, various combinations of the above and other variations can also be used, both within the solutions and across them. Altogether, since there are about 2 billion acres and about 6 billion humans on this planet, it means that theoretically on average it is sufficient that for example 1 in every 3 persons in the world will buy on average just 1 acre in order to save the entire remaining rainforest acres. Of course many people on the third world cannot afford even that, but on the other hand many people in the developed countries who understand the real value of this can buy much more than 1 acre, once they realize that on the long run this is one of the best investments they can ever make. Of course, someone like Bill Gates for example could buy the whole two billion acres alone. Of course the organization or organizations described here can also become an integral part of various governments, such as for example the government of Brazil itself.
[0041] Another problem is how to make sure that the rainforest lands bought indeed become protected, preferably in an efficient and cost-effective way, and how to start indeed sustainable harvesting in these lands. Of course, sustainable harvesting cannot be done at once necessarily in all the areas, and is also limited for example by market forces, such as for example the current world demand for a certain product. Therefore, preferably the organization does not guarantee that each acre will be used for producing anything but only for example that it will do its best to implement it in as many acres as possible. Therefore, when it comes to the sustainable harvesting, preferably each buyer becomes a partner in the total income of the organization from the sustainable harvesting, preferably proportionally to the number acres that he owns, and preferably additional investment is needed in order to participate in this, unless for example the buyer wants to go there and run the sustainable harvesting of his acres by himself. Various preferable solutions are possible for guarding the bought acres against destruction:
[0042] 1. Making deals with the respective governments so that by getting the much higher prices per acre than the $2 or less that they get for allowing to destroy each acre, they will also be obliged to guard at least the bought areas for example by Extended police forces and/or by parts of the army, and/or for example by other special forces designated for this. Another possible variation is that the preferably governments have to agree in return to change the laws if needed so that destroying rainforest lands and/or especially any of the lands that were already paid for, becomes punishable by preferably huge fines and preferably also imprisonments and actually enforce these rules, so that even without intensive guard all the time, the motivation for destroying rainforests becomes much lower.
[0043] 2. Making deals with the local populations and/or with indigenous natives, wherein they are paid for example a certain amount per month to guard large areas or at least to issue a warning immediately as soon as they spot dangerous or suspect activities, etc. However, this creates additional monthly expenses, so if used, it is preferably combined with at least some sustainable harvesting which can thus help cover these monthly expenses. In this case, preferably the same locals used for guarding the areas are preferably also employed for the sustainable harvesting. In fact, letting local people work for the sustainable harvesting and preferably also get additional revenues from the profits from the sustainable harvesting is very preferable, since otherwise they themselves take part in the destruction. According to Leslie Taylor, in Brazil for example the government encourages poor people to grab possession of forest lands and destroy them, with the motto of “land without men for men without land”, so that poor people squatter and destroy rainforest acres and create farms, but a short time afterwards the depleted land becomes useless and they have to move on to destroy more rainforest acres. Of course this motto also ignores the fact these the land are not really “without men” but are already populated by native Indians. She also quotes one Brazilian Official's public statement that “not until Amazonas is colonized by real Brazilians, not Indians, can we truly say we own it”. This attitude can lead to the sad realization that descendents of those same conquistadors who were directly or indirectly responsible for the depletion of these Indian populations during the last 500 years are also the ones who are now finishing the “job” of their ancestors by also destroying or allowing to destroy those rainforest lands for which they apparently don't have sufficient regard or appreciation of their true value. In order to stop this Locust-like behavior, clearly these masses of people have to be taken into account and become part of the solution. Another possible variation is to use, in addition or instead, hi-tech surveillance, such as for example through preferably low orbiting satellites, and/or for example zeppelins and/or balloons, which are much cheaper, that preferably report, preferably in real time, the conditions of the entire rainforests or at least large parts of them, so that any suspect or dangerous events can preferably be instantly spotted and appropriate action can be taken. Of course, since satellites are very expensive, preferably the organization uses services from existing surveillance satellites, such as for example NASA'a Terra MODIS Earth Observing Satellites. However another problem with satellites is that the stationary satellites that constantly cover the same area are at much higher orbit and thus have less resolution, whereas low orbiting satellites typically reach the same area only once every few hours or for example once a day or more, which might not be sufficient for real-time alerts. Preferably more Real-time alerts and more detailed data are used, because for example according to http://newsroom.msu.edu/news/archives/2003/02/rainforests.html, which quotes a recent report in Nature Magazine of Feb. 27, 2003, there are many small rainforests fires which can be easily stopped, but if neglected they can lead to subsequent huge intensity fires that are extremely difficult to put out. Zeppelins or balloons can be much cheaper and can remain constantly over the same areas and can still be also much lower than satellites. (The Zeppelins and/or balloons can be for example manned and/or for example small and preferably automatic or remote controlled. Preferably both types are used, for various purposes). Preferably these or other balloons or zeppelins are used also as one of the methods of carrying harvests from various areas, so that at least some of the problems of accessibility are solved this way. Preferably zeppelins and/or balloons can land for example in a few cleared areas that are preferably dispersed as needed or for example they stay above the canopy and the cargo is pulled up to them with ropes, which can for example be lowered from the zeppelin or balloon, or for example the rope is sent up with a smaller balloon and then the zeppelin pulls up the cargo that is attached to the rope on the ground. Preferably the zeppelins and/or balloons are powered by solar energy. Another possible variation is to use for example special vehicles that can move on any terrain without roads, for example vehicles that simulate animal legs, and/or for example use various animals that can carry cargo without roads. Another possible variation is to increase the price of the acres in order to finance also the guarding fee, so that for example as more acres are sold each month, they also help pay for the guarding of themselves and of the already sold acres. Theoretically of course guarding each acre separately would make it far too expensive, however since the acres are preferably parts of much larger clusters, the guarding is preferably more at the borders of these larger areas, so it is much cheaper when calculated as cost per acre, and it should become even cheaper per acre as more acres are sold. Anyway, if the organization can sustainably harvest for example even just 10% of the purchased acres and make for example just $1000 per acre per year by this, the average income per acre becomes $100 per year, which is quite enough for paying both for the guarding expenses and for the part of the profit that the client is entitled to, so that the organization can easily sustain itself. If for example the profit is $2400 per acre like Leslie Taylor's estimate or higher like for example the above higher estimate, and/or if a larger percent of the purchased acres can be sustainable harvested like this, then the figures are even much better.
[0044] 3. Creating different sources for fuel and for wood than rainforests, thus supplying the demand and removing much of the incentives that currently exist for continuing to destroy the rainforests. This can be done for example by encouraging and promoting the use of fast-growing plants that can easily replace wood, such as for example Kanef and/or industrial Hemp, which make in fact better wood fibers than ordinary trees and grow much faster. Hemp can grow for example to the size of a full tree within a few months, and has longer and better fibers than normal wood, so it can be used for example for creating better logs and/or fiber-boards, and can be also used for example for extracting Biomass fuel, for example in the form of Methylic Alcohol, which is much less polluting than current Gasoline, and is of course much more sustainable. Some of these plants can even be planted in rainforest lands that were already destroyed and deserted, since these are very resilient plants that can grow even is such destroyed places. It should be kept in mind that in recent years, except for the USA and a few other countries, in much of the world growing industrial hemp is legal now, including for example In North America: Canada; in Western Europe at least: England, Germany, France, Spain, Portugal, Austria, Denmark, Holland, Ireland, Italy and Switzerland; In Eastern Europe at least: Russia, Hungary, Romania, Poland, Slovenia, Croatia, Czech Republic and Ukraine; In East Asia at least: China, India, Korea and Thailand; In south America: At least Chile and Nicaragua; and it is also legal for example in South Africa, in Egypt, and in New Zealand.
[0045] 4. Preferably, in addition to the above, Class Action suits are filed, preferably against the multi-national organizations who destroy the rainforests and/or personally members of their managements that are involved in making these decisions and/or against governments and/or specific politicians that allow it, preferably on account of crimes against humanity, which are therefore relevant to the entire 6 billion humans that inhabit this planet and to their progeny who will all suffer the consequences of these acts. It is clear to see from the above descriptions of the consequences of destroying the rainforests that at least some of these consequences have an affect on every living creature on this planet, including the humans. Preferably these class suits are filed, to the extent possible, both in the countries where the destruction takes place, and in the countries where the centers of these multinational corporations are located, such as for example in the USA. Another possible variation is to try to file them also in any other country where the class suit system is sufficiently developed to allow this, since the victims are in every country on this planet. This is important both for bringing these issues more to the consciousness of everyone (since each such class action can get large media coverage), and for halting these organizations, since otherwise organizations that buy acres for $2 and make instantly $400 per acre have more buying power than an organization as described in this invention, who's income is based more on the long run. This is also important for showing those multinationals and governments that they ARE indeed accountable for what they are doing and will have to account for their actions now or in the future, in a way that preferably will also hurt them deeply in their pockets, and cannot escape or hide behind the claim that they are not the only ones responsible. However, since most of these governments are very poor, preferably those rich multinationals are sued also for paying back damages for the destruction already caused by them, whereas these governments are preferably sued only for future damages unless they immediately change their policies that allow the destruction to go on. Another possible variation is to also try to put on trial some of the above parties in the International tribunal in Hague for crimes against humanity. There is no problem of financing this, since class suits are almost invariably done by contingency lawyers, so there are practically no costs to the organization. These huge class action suits will probably eventually occur anyway, if not now, then after much more additional destruction has occurred or after the rainforests are completely gone, so it is much more preferable to do it now, while it can still lead to preventing a lot of the damage that is about to occur during the next few years. Another possible variation is, preferably in combination with these class action suits, to encourage consumer groups to boycott various products and/or companies that are responsible for large scale destruction of rainforests, such as for example Cow products from cows that are raised in these areas, etc. In addition, preferably the organization uses profits from the marketing of the acres and/or from the sustainable harvesting to invest in ecological education, preferably both in the countries where the main rainforests exists and also in other countries.
[0046] Of course, various combinations of the above and other variations can also be used, both within the solutions and across them.
[0047] While the invention has been described with respect to a limited number of embodiments, it will be appreciated that many variations, modifications, expansions and other applications of the invention may be made which are included within the scope of the present invention, as would be obvious to those skilled in the art. | The destruction of the rainforests in the last decades has become the biggest crime against humanity, animals and Nature. Various statistics show that at the current rate of destruction, unless drastic changes are made right now, by the year 2020 or even considerably earlier, 90-100% of all the rainforests will be irrevocably destroyed, causing damages that will take MILLIONS OF YEARS to repair, if at all. The present invention tries to solve this by creating a strong financial incentive that makes preserving the rain forests much more profitable than destroying them. Preferably sustainable harvesting is combined with selling real acres to people and making sure that these acres are indeed under supervision and protection and that preferably as many of them as possible are also used for sustainable harvesting. This is preferably combined with a recursive multi-level marketing plan with various sophisticated improvements over the prior art. | 65,543 |
BACKGROUND OF THE INVENTION
[0001] 1. Field of the Invention
[0002] The present invention relates to magnetic separation generally and, more particularly, but not by way of limitation, to a novel apparatus that permits the automatic separation of magnetic components in a laboratory microplate.
[0003] 2. Background Art
[0004] In the field of biology, there are requirements for the separation of one constituent from another. Some of the more commonly used methods are centrifugation, filtration, and magnetic separation. Centrifugation uses centrifugal force to provide separation by elements of mass. Filtration provides separation by size. Magnetic separation uses a magnetic field to attract and hold magnetic particles, or magnetic beads, so that the supernate in which the suspended are disposed can be removed.
[0005] Magnetic beads are particularly useful in immunoassays. Constituents of interest may be coated on the surface of paramagnetic particles. Using an applied magnetic field, the beads may be congregated and retained from the surrounding liquid reagents of reactants. U.S. Pat. No. 5,779,907, issued Jul. 14, 1998, to Yu, and titled MAGENTIC MICROPLATE SEPARATOR, describes a means and method of providing magnetic separation. As described in the patent, a laboratory tray, or microplate, containing a number of vertical wells is placed on a fixture having a number of upstanding cylindrical magnets. The arrangement of wells and magnets is such that each magnet is disposed adjacent four of the wells. Thus, a 96-well plate requires a fixture that has 24 magnets. The magnetic components in the wells are attracted to the sides of the wells adjacent the magnets. The supernate in the wells can then be removed. The apparatus described by Yu is entirely satisfactory for manual use; however, it does not meet the need of processing the large numbers of samples that are required in the fields of genomic and drug discovery research. Automation is required for processing large numbers of samples.
[0006] Conventionally, in automated magnetic separation systems, a robotic arm moves the laboratory trays over a fixed plate of magnets. While this provides an improvement over the manual method, it requires an additional positioning of the laboratory tray.
[0007] Accordingly, it is a principal object of the present invention to provide an apparatus for magnetic separation that does not require a separate step of positioning of the laboratory plate.
[0008] It is a further object of the invention to provide such an apparatus that can be remotely and automatically controlled.
[0009] It is an additional object of the invention to provide such an apparatus that can be economically constructed using conventional techniques.
[0010] It is another object of the invention to provide such an apparatus that can be part of a robotic liquid handling system.
[0011] Other objects of the present invention, as well as particular features, elements, and advantages thereof, will be elucidated in, or be apparent from, the following description and the accompanying drawing figures.
SUMMARY OF THE INVENTION
[0012] The present invention achieves the above objects, among others, by providing, in a preferred embodiment, an apparatus for automated magnetic separation of materials in laboratory trays, comprising: a frame upon an upper surface of which a multiwell laboratory tray may be placed, a base plate on which is mounted a plurality of upstanding magnets disposed below said upper surface; and means to raise said base plate such as to insert said upstanding magnets into interwell spaces in said laboratory tray.
BRIEF DESCRIPTION OF THE DRAWING
[0013] Understanding of the present invention and the various aspects thereof will be facilitated by reference to the accompanying drawing figures, provided for purposes of illustration only and not intended to define the scope of the invention, on which:
[0014] [0014]FIG. 1 is an isometric view of a microplate positioned over a plate of magnets.
[0015] [0015]FIG. 2 is a side elevational view of the invention, partially in cross-section, with a plate of magnets in lowered position.
[0016] [0016]FIG. 3 is a side elevational view of the invention, partially in cross-section, with a plate of magnets in raised position, such that the magnets are disposed between the wells of the microplate.
[0017] [0017]FIG. 4 is a block/schematic view of a control system for the present invention.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0018] Reference should now be made to the drawing figures on which similar or identical elements are given consistent identifying numerals throughout the various figures thereof, and on which parenthetical references to figure numbers direct the reader to the view(s) on which the element(s) being described is (are) best seen, although the element(s) may be seen on other figures also.
[0019] [0019]FIG. 1 illustrates a microplate 10 having a plurality of vertical wells, as at 12 , positioned over a plate of magnets 14 having a plurality of upstanding cylindrical magnets, as at 16 Wells 12 and magnets 16 are arranged such that, when microplate 10 and plate of magnets 14 are brought together, each magnet 16 will be moved into one of a plurality of positions, as at 20 , in the microplate and, so disposed, each magnet will be adjacent four of the wells. Microplate 10 is shown as having 96 wells arranged in a 8×12 matrix and plate of magnets 14 consequently has 24 magnets. It will be understood, however, that the invention may be applied as well to other numbers of microplate wells. In this position, the magnetic flux surrounding each magnet 16 encompasses four adjacent wells 12 . Paramagnetic particles in wells 12 will be attracted by this field and will be drawn to the sidewalls of the wells, adjacent to each magnet 16 . The supernate can then be withdrawn from the wells by, for example, aspiration.
[0020] [0020]FIG. 2 illustrates an apparatus, constructed according to the present invention, and generally indicated by the reference numeral 50 . Apparatus 50 includes a frame 60 having a horizontal bottom plate 62 and a horizontal top plate 64 , the latter having a plurality of vertical holes defined therethrough, as at 66 . A plurality of upstanding vertical magnets, as at 70 , is fixedly attached to a horizontal, non-magnetic base plate 72 that includes four bearings 74 (only two shown) journaled on four vertical guide pins 76 (only two shown) extending between and fixedly attached to bottom plate 62 and top plate 64 . Thus arranged, base plate 72 may move vertically upwardly and downwardly in frame 60 . Base plate 72 is held in its down position against four stops 80 (only two shown) fixedly attached to bottom plate 62 by the action of four compression springs 82 (only two shown) disposed around guide pins 76 and compressed between the lower surface of top plate 64 and the upper surface of the base plate.
[0021] A flexible bladder 90 disposed between the upper surface of bottom plate 62 and the lower surface of base plate 72 provides the motive force to raise the base plate. Bladder 90 may be simply constructed from a bicycle inner tube that is clamped between two clamps 100 fixedly attached to bottom plate 62 . One of clamps 100 is fitted with an air line connection (not shown) to permit flow of pressurized air to the closed interior of bladder 90 .
[0022] As shown on FIG. 2, a microplate 110 having a plurality of vertical wells 1 12 has been placed on the upper surface of top plate 64 . Since base plate 72 is shown in its lowered position, magnets 70 are spaced below wells 112 .
[0023] [0023]FIG. 3 illustrates the elements of apparatus 50 described above (FIG. 2), with pressurized air having been introduced into bladder 90 . The inflation of bladder 90 causes base plate 72 to rise, that motion causing magnets 70 to extend through openings 66 and between wells 112 . As will be understood from inspection of FIG. 1 and the accompanying text, each of magnets 70 will be inserted adjacent four of wells 112 in microplate 110 . Supernate can now be removed from wells 112 by any suitable means such as by aspiration of the supernate.. Expansion of bladder 90 is limited by the confines of frame 60 . The upward force provided by the inflation of bladder 90 exceeds the downward forces being applied by compression springs 82 , permitted the elevation of base plate 72 . Venting of compressed air from bladder 90 will cause the bladder to collapse and base plate 72 to return to its lowered position (FIG. 2) by means of the downward force provided by compression springs 82 .
[0024] [0024]FIG. 4 illustrates a control system that may be used with apparatus 50 , the control system being generally indicated by the reference numeral 200 . Control system 200 includes a system controller 210 that may be a section of a controller used to control other features of a complete analysis system. Controller 210 is operatively connected to control a three-way solenoid valve 220 that permits compressed air from a compressed air source 222 to inflate bladder 90 to raise base plate 72 to its elevated position (FIG. 3) or to vent air from the bladder to cause the base plate to move to its lowered position (FIG. 2).
[0025] The present invention provides a simple and effective means of moving magnets into the interwell spacing of a microplate by remote means. In the case described, low air pressure applied to a bladder, lifts the magnets.
[0026] Using a remotely controlled method of actuating the magnets into the interwell spacing permits the inclusion of the device into a liquid handling robot. This permits completed automation of the entire liquid handling function. The first step in bioassays, using magnetic beads or particles, is to react the coated elements on the beads with other liquid reagents. This requires the beads to be in suspension to provide full exposure of the reacting elements. Normally, some means of agitation is incorporated, such as shaking or multiple aspirations dispensings.
[0027] Following the reaction step is the separation step. A magnetic field is applied, drawing the magnetic beads to the sidewalls of the containing well. This separates the beads from the liquid in the well, permitting the liquid to be withdrawn by an automated pipettor. This process may be repeated multiple times, depending on the assay protocol and how many different reagent reactions are required.
[0028] By the use of a remote means of controlling the insertion of the magnets, the action may by easily accommodated in liquid handling robotics control systems, such as supplied by Tomtec, Inc., of Hamden, Conn. An actuating signal is generated in the control system software This signal controls an electrically operated solenoid valve that applies controlled air pressure to the device operating the magnets. By being small and compact, the magnetic device can be located directly on the robot's operating deck. In other words, frame 60 (FIGS. 2 and 3) simply replaces what would have been a fixed nest, to hold the microplate being used for the test.
[0029] This simplicity eliminates the necessity of physically moving the microplate from the station where it receives the reagent, without magnetization, to a station with magnetization. The invention permits the system control to apply magnetization on demand where and when it is required.
[0030] In the embodiments of the present invention described above, it will be recognized that individual elements and/or features thereof are not necessarily limited to a particular embodiment but, where applicable, are interchangeable and can be used in any selected embodiment even though such may not be specifically shown.
[0031] Terms such as “upper”, “lower”, “inner”, “outer”, “inwardly”, “outwardly”, “vertical”, “horizontal”, and the like, when used herein, refer to the positions of the respective elements shown on the accompanying drawing figures and the present invention is not necessarily limited to such positions.
[0032] It will thus be seen that the objects set forth above, among those elucidated in, or made apparent from, the preceding description, are efficiently attained and, since certain changes may be made in the above construction without departing from the scope of the invention, it is intended that all matter contained in the above description or shown on the accompanying drawing figures shall be interpreted as illustrative only and not in a limiting sense.
[0033] It is also to be understood that the following claims are intended to cover all of the generic and specific features of the invention herein described and all statements of the scope of the invention which, as a matter of language, might be said to fall therebetween. | In a preferred embodiment, an apparatus for automated magnetic separation of materials in laboratory trays, including: a frame upon an upper surface of which a multiwell laboratory tray may be placed; a base plate on which is mounted a plurality of upstanding magnets disposed below the upper surface; and apparatus to raise the base plate such as to insert the upstanding magnets into interwell spaces in the laboratory tray. | 13,464 |
"BACKGROUND \n [0001] A common environment scenario is mixed-mode, wherein differing versio(...TRUNCATED) | "Versioning management provides for efficient and effective handling of varying policy versions, cli(...TRUNCATED) | 95,596 |
"TECHNICAL FIELD \n [0001] The invention relates to a broadcast communication system archit(...TRUNCATED) | "This invention discloses a digital TV broadcast system coordinated with a broadband communication n(...TRUNCATED) | 50,572 |
"BACKGROUND OF THE INVENTION \n 1. Field of the Invention \n The present invention relates t(...TRUNCATED) | "The present invention provides novel carbonic anhyrase inhibitors represented by the structural for(...TRUNCATED) | 53,613 |
"This is a division, of application Ser. No. 749,589, filed June 27, 1985, now abandoned. \n \n (...TRUNCATED) | "An integrated circuit in complementary circuit technology comprising two field effect transistors ((...TRUNCATED) | 16,046 |
"[0001] This application is a divisional of application Ser. No. 10/226,190, filed on Aug. 23, 20(...TRUNCATED) | "An image sensor includes a pixel having a protection circuit connected to a charge multiplying phot(...TRUNCATED) | 27,186 |
Sampled Big Patent Dataset
This is a sampled Trelis/big_patent_sample dataset containing rows of data with descriptions shorter than or equal to 100,000 characters in length.
--- Sampled from Trelis/big_patent_sampled ---
Sampled big_patent Dataset
This is a sampled big_patent dataset - sampled down for shorter fine-tunings.
The data is sampled with the aim of providing an even distribution across data lengths. The distribution is quite flat up until 1 million characters in length, making the dataset good for training on lengths up to 250,000 tokens.
Dataset Card for Big Patent
Dataset Summary
BIGPATENT, consisting of 1.3 million records of U.S. patent documents along with human written abstractive summaries. Each US patent application is filed under a Cooperative Patent Classification (CPC) code. There are nine such classification categories:
- a: Human Necessities
- b: Performing Operations; Transporting
- c: Chemistry; Metallurgy
- d: Textiles; Paper
- e: Fixed Constructions
- f: Mechanical Engineering; Lightning; Heating; Weapons; Blasting
- g: Physics
- h: Electricity
- y: General tagging of new or cross-sectional technology
Current defaults are 2.1.2 version (fix update to cased raw strings) and 'all' CPC codes:
from datasets import load_dataset
ds = load_dataset("big_patent") # default is 'all' CPC codes
ds = load_dataset("big_patent", "all") # the same as above
ds = load_dataset("big_patent", "a") # only 'a' CPC codes
ds = load_dataset("big_patent", codes=["a", "b"])
To use 1.0.0 version (lower cased tokenized words), pass both parameters codes
and version
:
ds = load_dataset("big_patent", codes="all", version="1.0.0")
ds = load_dataset("big_patent", codes="a", version="1.0.0")
ds = load_dataset("big_patent", codes=["a", "b"], version="1.0.0")
Supported Tasks and Leaderboards
[More Information Needed]
Languages
English
Dataset Structure
Data Instances
Each instance contains a pair of description
and abstract
. description
is extracted from the Description section of the Patent while abstract
is extracted from the Abstract section.
{
'description': 'FIELD OF THE INVENTION \n [0001] This invention relates to novel calcium phosphate-coated implantable medical devices and processes of making same. The unique calcium-phosphate coated implantable medical devices minimize...',
'abstract': 'This invention relates to novel calcium phosphate-coated implantable medical devices...'
}
Data Fields
description
: detailed description of patent.abstract
: Patent abastract.
Data Splits
train | validation | test | |
---|---|---|---|
all | 1207222 | 67068 | 67072 |
a | 174134 | 9674 | 9675 |
b | 161520 | 8973 | 8974 |
c | 101042 | 5613 | 5614 |
d | 10164 | 565 | 565 |
e | 34443 | 1914 | 1914 |
f | 85568 | 4754 | 4754 |
g | 258935 | 14385 | 14386 |
h | 257019 | 14279 | 14279 |
y | 124397 | 6911 | 6911 |
Dataset Creation
Curation Rationale
[More Information Needed]
Source Data
Initial Data Collection and Normalization
[More Information Needed]
Who are the source language producers?
[More Information Needed]
Annotations
Annotation process
[More Information Needed]
Who are the annotators?
[More Information Needed]
Personal and Sensitive Information
[More Information Needed]
Considerations for Using the Data
Social Impact of Dataset
[More Information Needed]
Discussion of Biases
[More Information Needed]
Other Known Limitations
[More Information Needed]
Additional Information
Dataset Curators
[More Information Needed]
Licensing Information
[More Information Needed]
Citation Information
@article{DBLP:journals/corr/abs-1906-03741,
author = {Eva Sharma and
Chen Li and
Lu Wang},
title = {{BIGPATENT:} {A} Large-Scale Dataset for Abstractive and Coherent
Summarization},
journal = {CoRR},
volume = {abs/1906.03741},
year = {2019},
url = {http://arxiv.org/abs/1906.03741},
eprinttype = {arXiv},
eprint = {1906.03741},
timestamp = {Wed, 26 Jun 2019 07:14:58 +0200},
biburl = {https://dblp.org/rec/journals/corr/abs-1906-03741.bib},
bibsource = {dblp computer science bibliography, https://dblp.org}
}
Contributions
Thanks to @mattbui for adding this dataset.
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