Abstract:
A combination of a FOUP (front opening unified pod) system and a reticle system utilized for the transport of wafers and a reticle system, the latter of which are used for transporting reticles from a first fabrication site to a further site at another location, and which provides for a unified system enabling the automated and trackable delivery of the reticles between these sites. Provided is a modified FOUP base structure, which is adapted to retain a reticle and to be able to employ existing equipment in a fabrication site which only necessitates a minimal modification of the equipment in order to render the latter universally adaptable to the combination of the systems.

Description:
This application is a continuation of U.S. patent application Ser. No. 11/306,708, filed Jan. 9, 2006. 
    
    
     BACKGROUND 
     The present invention relates to the unique combining of a FOUP (front opening unified pod) system utilized for the transport of wafers and a reticle system, the latter of which are used for transporting reticles from a first fabrication site to a further site at another location, and which provides for a unified system enabling the automated and trackable delivery of the reticles between these sites. 
     In particular, the invention is directed to the provision of a unique modified FOUP base structure, which is adapted to retain a Reticle Storage Pod (RSP) and to be able to employ existing material transport equipment in a fabrication site which only necessitates a minimal modification of the equipment in order to render the latter universally adaptable to the combination of the systems. 
     In essence, the utilization of Reticle Storage Pods (RSPs) is well known in the technology, wherein RSP carriers are conveyed on OHT (Overhead Transport) vehicles or conveyor tracks. Similarly, currently existing FOUP (front opening unified pod) Automated Material Handling Systems (AMHS) are employed in a generally segregated mode from the RPS carriers and, in effect, are designed for an independent operation, which is not coordinated therewith. Consequently, it is intended, by means of the present invention, to provide a unique combination of such normally unrelated systems, which combine the capabilities of automated RSP carriers or transports with currently existing FOUP AMH systems. 
     At this time, currently existing fabrication automated systems handle FOUPs and RSP carriers on essentially the same OHT (Overhead Transport) vehicles or tracks in a separate and basically uncoordinated manner. As a consequence, semiconductor fabrication is burdened with the addition of extensive structural and functional requirements needed to move reticles supporting wafers being processed to diverse areas or new fabrication regions, whereby such requirements may be prohibitive in nature. Moreover, although manual transportation of the wafers and reticles is an option, this mode of operation is slow in functioning, and may, at times, result in excessive breakage and loss of reticles. Furthermore, an automated delivery of the components to other fabrication locations or additions to existing fabrication sites requires the provision of an automated and readily trackable system, which is suited for the transport and controlling of the reticles being conveyed between those sites or locations. 
     It is also important to be able to uniquely combine RSP transportation with preexisting or currently employed FOUPs, the latter of which are equipped with an RSP adapter assembly and whereby any FOUP could retain a plurality of RSPs through a concept of utilization of a wafer adaptation plate, which retains the RSPs, and which can be employed in conjunctive operation with end effectors and most robotic installations utilized currently in the technology. 
     Presently, no combination of such RSP transport systems and FOUP AMHS systems are known to be available, and these systems are ordinarily employed as independent and autonomously functioning installations in various semiconductor processing and fabrication locales or sites. 
     Liu-Barba, et al., U.S. Pat. No. 6,655,898 B1, discloses an arrangement for the cycling of FOUPs (front opening unified pods). The publication is directed to an essentially stand-alone apparatus, which cycles FOUPs, hoisting the latter up and down and levering a counterbalance relationship between two FOUPs which are involved in this process. This has nothing in common with providing a Reticle Storage Pod (RSP) arrangement, which is adapted to be combined with a FOUP transport system, as disclosed by the present invention. 
     Blattner, et al., U.S. Patent Publication No. 2003/0161714 A1, does not disclose an inter-building reticle transport arrangement and is primarily directed to the provision of a storage and buffer system with transport elements, which do not in any manner combine the normally diverse transport systems for RSPs and FOUPs in a manner analogous to that of the present invention. 
     Ow, et al., U.S. Pat. No. 6,165,268, discloses a method of providing modifications for facilitating 200-millimeter wafer cassettes adapted to be mounted for processing on a 300-millimeter wafer FOUP load port. Provided in the disclosed apparatus is an adapter fixture, which is placed on a 300 millimeter load port kinematic loading pins and an open 200 millimeter wafer cassette is adapted to be positioned thereon. To the contrary, the present invention describes a method and apparatus for adapting a 300-millimeter wafer transport system to transport reticles (RSPs) in a combined arrangement therewith. 
     Busby, U.S. Pat. No. 6,095,335, discloses an apparatus within a FOUP arrangement adapted to accommodate differently sized wafers, such as positioning 200-millimeter wafers inside a 300-millimeter FOUP through a size conversion capability. This has nothing in common with the adaptation of a conveyer system to combine transport Reticle Storage Pods (RSPs) and FOUP transport systems for operation on a common transport arrangement intended to extend between different fabrication facilities and processing sites. 
     BRIEF SUMMARY 
     Accordingly, pursuant to the invention, there is provided a novel and unique combined or composite transportation system, which, in a reliable manner, imparts an automated RSP (Storage Pod) transport capability to an existing FOUP (front opening unified pod) Automated Material Handling System (AMHS). This is effected in that in a simple and inexpensive mode, it is possible to impart diverse capabilities to both transportation systems through the combination thereof in conveying reticles containing semiconductor wafers from one fabrication facility to a second facility or building locale, and wherein there is only required essentially a modified FOUP handling flange structure, and wherein, pursuant to a further modification, multiple RSPs can be transported in a FOUP. 
     In order to achieve the foregoing novel aspects, pursuant to the invention there is provided a single or unitary track transport or conveying system for overhead transport vehicles (OHT) or tracks, which is capable of handling both FOUPs and RSP carriers through the feature in that currently existing FOUPs are equipped with an RSP adapter assembly. Pursuant to the invention, the assembly, which adapts the RSPs to FOUPs, thereby implementing the combined transport capability, can be readily installed in any FOUP, and may hold a plurality, preferably up to three RSPs, which are employed in transporting semiconductor wafers. Hereby, a suitable adapter, which is installed in connection with the FOUPs, may be of the same size as that for a 300 millimeter wafer, possessing three locating kinematic mount pins in order to simulate a load port, and whereby up to three RSPs can be simultaneously transported by a FOUP to any particular location or site within a transport region or processing areas, such as between various fabrication buildings. 
     Moreover, pursuant to the present invention, an adapter of customized construction may be provided, whereby the adapter is mounted inside a FOUP so as to also enable the latter to hold three RSPs. Concurrently, end effectors and robots are presently available whereby FOUPs are handled in connection with the RSPs, and can be readily adapted in a novel and unique manner to the transfer device to remove and transfer the pods to load ports between the fabrication sites. 
     Accordingly, pursuant to the present invention, it is an object to provide a unified system or arrangement for transporting RSPs in a FOUP transport arrangement. 
     Pursuant to another object of the present invention, there is provided a capability of loading FOUPs in which an automated robot can read RSP and FOUP IDs, load RSPs into the FOUP and then transport the FOUP to another transfer station where the process may be reversed and the RSP delivered as may be required in conformance with specific manufacturing requirements. 
     A further object of the present invention resides in providing a combined or unified system whereby segregated automation transport loops consisting of a reticle transport and a FOUP transport arrangement are operatively combined through a simple transport container modification. 
     Another object of the present invention is to provide structure for storing and carrying at least one Reticle Storage Pod (RSP) in an adapted FOUP structure, and whereby there is also provided the capability of simultaneously carrying multiple RSPs in the adaptive FOUP structure. 
     Still another object of the present invention is to provide a novel structure to handle RSPs in an RFA (Reticle FOUP Adapter Plate) located in a FOUP by providing an adapter modification in the FOUP. 
     Further means are provided to track the RSP versus rewriting to RFA or FOUP and then resetting after an overhead transport vehicle (OHT) is conveyed to a destination transfer station. 
     Pursuant to a further object of the invention there is provided an arrangement and a method of handling an RSP versus a FOUP stocker and RFA or a modified FOUP, including an arrangement for utilizing an OHT vehicle or device to, respectively, load and unload an RSP or multiple RSPs into a FOUP. 
     According to a further object of the invention there is provided an arrangement utilizing a conveyer to load an RSP into and out of a FOUP, and also to locate and secure an RSP via a wafer adapter design for positioning the RSP into a FOUP. 
    
    
     
       BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWINGS 
       Reference may now be made to the following detailed description of preferred embodiments of the invention, taken in conjunction with the accompanying drawings; in which: 
         FIG. 1  illustrates a perspective, generally diagrammatic, representation of a reticle to FOUP interface stocker arrangement; 
         FIG. 2  illustrates a perspective representation of a reticle to FOUP adapter with a Reticle Storage Pod (RSP) arranged thereon and with an empty adapter located adjacent thereto; 
         FIG. 3  illustrates, generally diagrammatically, a side view of a Reticle Storage Pod (RSP) located on a RSP and FOUP conveyor structure; 
         FIG. 4  illustrates a top plan view of the conveyor of  FIG. 3 ; 
         FIG. 5  illustrates a reticle hoist above the conveyor; 
         FIG. 6  illustrates a FOUP SRC above the conveyor; 
         FIGS. 7A through 7E  illustrate diagrammatically the sequence of loading and unloading of a Reticle Storage Pod (RSP) employed in connection with the RSP FOUP conveyor; 
         FIG. 8  illustrates diagrammatically an RSP FOUP showing a reticle pod for semiconductor wafers, which are to be arranged therein; 
         FIG. 9  illustrates a sectional view taken along line  9 - 9  in  FIG. 8 ; 
         FIG. 10  illustrated a plan view taken along line  10 - 10  in  FIG. 8 ; 
         FIG. 11  illustrates a bottom view of the RSP FOUP showing a conveyor table utilized therewith; 
         FIGS. 12 ,  13  and  14  illustrate, generally diagrammatically, a top-loading RSP FOUP structure in, respectively, front, rear and partly-sectional side views; 
         FIGS. 15 ,  16  and  17  illustrate, respectively, a top-loading RSP FOUP structure in a load sequence; and 
         FIG. 18  illustrates a schematic representation of the RSP FOUP transport system extending between a first location to a further location along the route of conveyance of the combined reticle and FOUP RSP transport system. 
     
    
    
     DETAILED DESCRIPTION 
     Reverting in particular detail to the invention, and as diagrammatically illustrated in  FIG. 1 , there is shown a reticle to FOUP interface stocker  10  showing a first conveyor track  12  having a movable FOUP SRC vehicle  14  displaceably arranged thereon; and a LIM (linear induction motor) track system  16  connected to the upper side surface of the reticle to FOUP interface stocker; an RFA (reticle to FOUP adapter) storage  18  is at the top of the stocker  10 , which is adapted to be arranged adjacent a FOUP unit  20  and which is adapted to provide for the conveyance of pluralities of stocked reticles to the LIM track system for transference along the transport system. 
     Illustrated is also a track  22  showing a further vehicle  24  for a reticle SRC and an RSP-to-FOUP-adapter arrangement and which is transportable through a two-way RSP input and output. A manual operator input/output device  26  is provided for, and is for the purpose of receiving the reticle and the FOUP arrangement. 
     As represented in  FIG. 2  of the drawings, there is shown an RSP-to-FOUP-adapter (RFA)  30 , with a side-by-side view of an adapter  30  having an RSP positioned thereon, and an adjacent empty adapter, wherein this construction of adapter has the same base form  32  as that of a FOUP and is handled from below by the stocker  10  and the LIM track system  16  in a manner analogous to the manipulation of a FOUP. 
     As shown in  FIG. 1 , the RSPs are loaded and unloaded via the reticle SRC hoist, and an RFA inventory is maintained in the therewith-dedicated FOUP stocker  10 . 
     The RFA inventory is controlled by means of a suitable RF identifier or tag, and utilized are FOUP and RSP kinematic positioning aspects through the suitable addition of guides, which aid in loading and prevent inadvertent RSP to adapter movement. The positioning is provided for by means of upstanding pins  31  as shown in the adjacent empty adapter of  FIG. 2 , and the RFAs are capable of accommodating both single RSPs or such multiple “six-pack” reticle pods; which RFAs, if desired, can be loaded at the manual I/O part of the stocker  10 . 
     As illustrated in  FIG. 3  of the drawings, there is schematically illustrated a segment of a conveyor arrangement  50 , which by way of example, may be a reticle roller conveyor, and having a reticle pod, as illustrated in  FIG. 2 , movably positioned thereon, and connected at one end to a pick-and-place conveyor  52  mounting an RSP FOUP  54 . 
     The reticle roller conveyer, as also shown in the top plan view of  FIG. 4 , as well as end views of  FIGS. 5 and 6 , has the reticle SRC connected thereto for receiving the reticle pods and also the RSP FOUP  54 . 
     As shown in  FIGS. 7A through 7E  of the drawings, there are illustrated the respective loading and unloading sequences, wherein the reticle is being loaded into the FOUP and then downwardly displaced so as to be adapted to be conveyed to a loading system for further transfer between manufacturing sites. The reverse is also applicable thereto, in effect, the upward movement of empty FOUPs for loading again with RSPs. 
     As shown in  FIGS. 8-11  of the drawings, there is illustrated an RSP FOUP  70  showing an RSP  72  with a three-pin wafer mounting unit  74 , and a suitable guide element  84 , which is usually employed for the stationary positioning of a 300 millimeter wafer standard FOUP. In this instance, the reticle port is arranged in a FOUP  78  and a flange  80  is provided for adapting the FOUP to SRCs. The bottom of the RSP  72  includes structure for support thereof on a conveyor table  82 . 
     Referring now in specific detail to  FIGS. 12-14  of the drawings, illustrated in  FIG. 12  is a side view of a closed FOUP  90  showing Reticle Storage Pods (RSPs)  92  for reticles arranged therein in a stacked position. In this instance, as previously indicated, three (3) RSPs, each of which is adapted to support a reticle during the processing or manufacturing steps thereof, are located interiorly of the FOUP, and may be stacked therein utilizing the OHT  100 , as illustrated in  FIG. 15 . 
     As shown in  FIG. 12 , the FOUP structure  90  includes a top flange  94  adapted to be supported on an overhead transport track or vehicle (OHT), and wherein the FOUP illustrates a door  96  thereof with the RSP magazine attached thereto. 
     As illustrated in  FIG. 13  of the drawings showing a side view of the FOUP body  90 , with the door  96  removed; whereas in  FIG. 14  of the drawings, there is illustrated the FOUP door  96  in an open position with the top RSP flange enabling removal of the nested RSPs, which contains reticles. 
     As illustrated in  FIGS. 15-17 , this discloses the RSP FOUP loading sequence in connection with a top loading construction. 
     In particular, the FOUP overhead transport  100 , as shown in  FIG. 15 , includes a structure  102 , which is supported from an overhead transport rail  104 , and which is adapted to engage a FOUP  106 , the latter of which may contain RSPs in a stacked or superimposed nested position. 
     In the aspect of loading the RSPs with the RSP overhead transport (RSP OHT)  108 , a further rail  110  has the RSP transport unit  112  arranged thereon and which may be vertically displaceable, and which, as shown in  FIG. 15 , is adapted to load reticles into the opened portion or door of the FOUP  106 . In this connection, a suitable sensor or sensors  114  may be provided for detecting the RSPs, which are deposited into the open door portion  120  of the FOUP  106 , which is opened using the door opener mechanism  116 , such as shown in  FIG. 14  of the drawings, as previously referred to. 
     Upon the RSPs having been loaded through the open portion of the FOUP, the RSP FOUP door  120  is closed, as illustrated in  FIG. 16 , so as to provide a closed top loaded RSP FOUP  122 , as shown, for example, in  FIG. 12  of the drawings, by being moved along a track portion  124  in a horizontal manner. Thereafter, the RSP FOUP  122  is lifted upwardly into the transport unit  126  for the RSP FOUP, for transporting the loaded RSP FOUP  122  to a further site for manufacture or processing, as described hereinbelow. 
     Referring to  FIG. 18  of the drawings, there is illustrated a schematic representation of the transport of an RSP FOUP  122  between a different manufacturing or processing sites for semiconductor wafers or similar components of integrated circuits or microprocessor devices. 
     As shown in the drawing, the RSP SRC  130  deposits the RSPs in the RSP FOUP transport conveyor, as provided for in  FIGS. 15-17  of the drawings. 
     Thereafter, the FOUP SRCs and the RSP are transported into a standard FOUP stocker  132 , which also combines the RSP and the wafer FOUP for further transport into an interbuilding stocker  134 , whereupon the RSPs are then forwarded to a FOUP structure and the RSP and the RSP interconnections are then removed from the FOUP conveyor at that further location, which may be at a manufacturing annex or further processing site. 
     The entire transport procedure with the empty FOUPs may then be returned to the initial locale or site so as to be able to again repeat the foregoing loading and transport procedure. 
     From the foregoing, it is clearly evident that due to the combination and the use of an adapter, which correlates and combines the RSP with FOUP conveyor or transport systems, these separate transport arrangements can be combined to present a single straightforward solution at minimum cost and equipment modifications, and is adapted to increase LIM capacity so as to also meet RFA quantity requirements. 
     The RSP is protected in a FOUP-like container, which permits handling and transport by means of the top flange, as shown in  FIGS. 8-11  of the drawings, and an existing vertical motion capability of FOUP and RSP overhead transport is employed to load and unload the RSPs, as shown in  FIG. 3  of the drawings. 
     The provision of the unique FOUP opening system enables positioning the RSP FOUP for loading and is adapted to be employed for factory floor level automated OHT RSP loadings; factory floor level manual RSP loading or sealing level automated OHT RSP loading. 
     The structure, as shown, is clearly adapted to enable the loading and unloading in an option of the Reticle Storage Pods in the FOUP shown with the door with RSP magazine attached and with the FOUP opened and the top OHT flange. 
     As indicated, the FOUP overhead transport track enables the FOUP OUT vehicle to engage the RSP FOUP and the FOUP door opener by means of the through-beam RSP sensors. 
     While the present invention has been particularly shown and described with respect to preferred embodiments thereof, it will be understood by those skilled in the art that the foregoing and other changes in forms and details may be made without departing from the scope and spirit of the present invention. It is therefore intended that the present invention not be limited to the exact forms and details described and illustrated, but fall within the scope of the appended claims.