Wet clean system design

The present invention generally provides an apparatus and method for processing and transferring substrates in a multi-chamber processing system that has the capability of receiving and performing single substrate processing steps performed in parallel, while using the many favorable aspects of batch processing. Embodiments of the invention described herein are adapted to maximize system throughput, reduce system cost, reduce cost per substrate during processing, increase system reliability, improve the device yield on the processed substrates, and reduce system footprint. In one embodiment, the cluster tool is adapted to perform a wet/clean process sequence in which various substrate cleaning processes are performed on a substrate in the cluster tool.

BACKGROUND OF THE INVENTION

1. Field of the Invention

Embodiments of the invention generally relate to an integrated processing system containing multiple processing stations and robots that are capable of processing multiple substrates in parallel.

2. Description of the Related Art

The process of forming electronic devices is commonly done in a multi-chamber processing system (e.g., a cluster tool) that has the capability to sequentially process substrates, (e.g., semiconductor wafers) in a controlled processing environment. Typical cluster tools used to perform semiconductor cleaning processes, commonly described as a wet/clean tool, will include a mainframe that houses at least one substrate transfer robot which transports substrates between a pod/cassette mounting device and multiple processing chambers that are connected to the mainframe. Cluster tools are often used so that substrates can be processed in a repeatable way in a controlled processing environment. A controlled processing environment has many benefits which include minimizing contamination of the substrate surfaces during transfer and during completion of the various substrate processing steps. Processing in a controlled environment thus reduces the number of generated defects and improves device yield.

The effectiveness of a substrate fabrication process is often measured by two related and important factors, which are device yield and the cost of ownership (CoO). These factors are important since they directly affect the cost to produce an electronic device and thus a device manufacturer's competitiveness in the market place. The CoO, while affected by a number of factors, is greatly affected by the system and chamber throughput, or simply the number of substrates per hour processed using a desired processing sequence. A process sequence is generally defined as the sequence of device fabrication steps, or process recipe steps, completed in one or more processing chambers in the cluster tool. A process sequence may generally contain various substrate (or wafer) electronic device fabrication processing steps. In an effort to reduce CoO, electronic device manufacturers often spend a large amount of time trying to optimize the process sequence and chamber processing time to achieve the greatest substrate throughput possible given the cluster tool architecture limitations and the chamber processing times.

Other important factors in the CoO calculation are the system reliability and system uptime. These factors are very important to a cluster tool's profitability and/or usefulness, since the longer the system is unable to process substrates the more money is lost by the user due to the lost opportunity to process substrates in the cluster tool. Therefore, cluster tool users and manufacturers spend a large amount of time trying to develop reliable processes, reliable hardware, reliable transferring methods and reliable systems that have increased uptime.

Extraordinarily high levels of cleanliness are generally required during the fabrication of semiconductor substrates. During the fabrication of semiconductor substrates, multiple cleaning steps are typically required to remove impurities from the surfaces of the substrates before subsequent processing. The cleaning of a substrate, known as surface preparation, has for years been performed by collecting multiple substrates into a batch and subjecting the batch to a sequence of chemical and rinse steps and eventually to a final drying step. A typical surface preparation procedure may include etch, clean, rinse and dry steps. During a typical cleaning step, the substrates are exposed to a cleaning solution that may include water, ammonia or hydrochloric acid, and hydrogen peroxide. After cleaning, the substrates are rinsed using ultra-pure water and then dried using one of several known drying processes.

Moreover, the push in the industry to shrink the size of semiconductor devices to improve device processing speed and reduce the generation of heat by the device, has reduced the industry's tolerance for process variability. To minimize process variability an important factor in semiconductor fabrication processes is the issue of assuring that every substrate run through a cluster tool sees the same processing conditions or receives the highest quality deposition or cleaning process steps. Conventional batch cleaning processes often do not provide results that are repeatable and uniform for each substrate positioned within the batch or from batch to batch.

In some cases, various semiconductor processes are advantageously performed using a substrate in a vertical orientation, wherein the typical processing surface(s) of the substrate face a horizontal direction. Such processes generally include cleaning processes (e.g., Marangoni drying), where insertion and removal of the substrate are critical to the performance of the process, or where the footprint of the processing apparatus is minimized by processing the substrate in a vertical orientation. However, batches of substrates are typically transferred and positioned in an input device in a cluster tool, such as a substrate cassette and/or FOUPs in a horizontal orientation. Transferring and supporting batches of substrates in a horizontal orientation is advantageous, because of the likelihood of generating particles due to the tipping and/or “rattling” of the substrates in the cassette due to the inherent instability of a semiconductor substrate that is positioned in a vertical orientation. Therefore, to transfer, orient and position a substrate from a horizontal to a vertical orientation requires the use of one or more substrate tilting device. Conventional processing systems generally require at least one or more devices positioned within each processing chamber or in a position near the processing chamber to rotate the substrate in a vertical orientation so that it can be processed vertically. In some cases multiple substrate tilting devices can be used to rotate the substrate into a vertical orientation to avoid being a bottleneck to the process sequence. Having multiple substrate tilting devices can greatly affect the reliability of the cluster tool, since the overall system reliability is proportional to the product of the reliability of each component in the system. Thus adding multiple chambers that can tilt or rotate a substrate to a vertical orientation degrades the reliability of the whole cluster tool.

Also, the process of rapidly transferring and positioning a substrate in a cluster tool generally requires a robot to grip the substrate so that the substrate will not slide on the robot blade while robot is accelerated and decelerated during the transferring process. Sliding on the robot blade will generate particles and/or cause the substrate to become chipped, which greatly affects device yield and CoO performance of the cluster tool.

Therefore, there is a need for a system, a method and an apparatus that can transfer and receive a substrate in a horizontal and vertical orientation, provide a reliable transferring process. There is also a need for a cluster tool that can meet the required device performance goals, has a high substrate throughput, and thus reduces the process sequence CoO.

SUMMARY OF THE INVENTION

The present invention generally provide an cluster tool for cleaning a substrate, comprising two or more process chambers that are configured to process a substrate in a vertical orientation, wherein the two or more process chambers are positioned a distance apart along a first direction, a robot assembly that comprises a first robot having a robot blade assembly that has a substrate supporting surface, and the first robot is adapted to position a substrate at one or more points generally contained within a first plane, wherein the first plane is generally parallel to the first direction, an actuator that is coupled to the robot blade assembly and is adapted to position the substrate supporting surface in an angular orientation relative to a horizontal plane, a first motion assembly that is adapted to position the first robot in a third direction that is generally perpendicular to the first plane, and a second motion assembly that is adapted to position the first robot in a direction generally parallel to the first direction, a chamber actuator assembly that has two or more end-effector assemblies that each have a substrate supporting surface, wherein the chamber actuator assembly is adapted to position one of the two or more end-effector assemblies in each of the two or more process chambers generally simultaneously, two or more substrate supports that are each adapted to receive one or more substrates from the first robot assembly, and a support actuator that is adapted to position the two or more substrate supports so that each of the two or more end-effector assemblies can receive a substrate from at least one of the two or more substrate supports.

Embodiments of the invention further provide a cluster tool for cleaning a substrate, comprising a first processing rack comprising two or more process chambers that each have one or more walls that form a processing region, wherein each of the two or more process chambers are configured to process a substrate in a vertical orientation, a chamber actuator assembly that are adapted to dispose a substrate in each of the two or more process chambers generally simultaneously, and a fluid source that is fluidly coupled to each of the two or more process chambers, wherein the fluid source is adapted to deliver a desired volume of a liquid to the processing regions of each of the two or more processing chambers from a fluid reservoir, and a robot assembly that comprises a first robot having a robot blade assembly that has a substrate supporting surface, and the first robot is adapted to position a substrate at one or more points generally contained within a first plane, wherein the first plane is generally parallel to the first direction and a second direction, an actuator that is coupled to the robot blade assembly and is adapted to position the substrate supporting surface in an angular orientation relative to a horizontal plane, a first motion assembly that is adapted to position the first robot in a third direction that is generally perpendicular to the first plane, and a second motion assembly that is adapted to position the first robot in a direction generally parallel to the first direction.

Embodiments of the invention further provide a method of processing a substrate in a cluster tool, comprising positioning a first substrate on a first substrate supporting device using a robot assembly, positioning a second substrate on a second substrate supporting device using the robot assembly, transferring the first substrate to a first end-effector and the second substrate to a second end-effector, positioning the first substrate in a processing region of a first processing chamber and the second substrate in a processing region of a second processing chamber simultaneously, simultaneously disposing a first processing liquid in the first processing region and the second processing region simultaneously.

Embodiments of the invention further provide a cluster tool for cleaning a substrate, comprising two or more process chambers that are configured to process a substrate in a vertical orientation, wherein the two or more process chambers are positioned a distance apart along a first direction, and each of the two or more process chambers comprise one or more walls that form a processing region, and a first megasonic actuator that is adapted to deliver energy to a processing side of a substrate that is positioned in the processing region, a robot assembly that comprises a first robot having a robot blade assembly that has a substrate supporting surface, and the first robot is adapted to position a substrate at one or more points contained within a first plane, wherein the first plane is parallel to the first direction, a first motion assembly that is adapted to position the first robot in a third direction that is perpendicular to the first plane, and a second motion assembly that is adapted to position the first robot in a direction parallel to the first direction, a chamber actuator assembly that has two or more end-effector assemblies, wherein the chamber actuator assembly is adapted to position one of the two or more end-effector assemblies in each of the two or more process chambers simultaneously, two or more chamber pass-through supports that are each adapted to receive one or more substrates from the robot assembly, and a support actuator that is adapted to position the two or more chamber pass-through supports so that each of the two or more end-effector assemblies can simultaneously receive a substrate from at least one of the two or more chamber pass-through supports.

DETAILED DESCRIPTION

The present invention generally provides an apparatus and method for processing and transferring substrates in a multi-chamber processing system (e.g., a cluster tool) that has the capability of receiving and performing single substrate processing steps performed in parallel, while using the many favorable aspects of batch processing. Embodiments of the invention described herein are adapted to maximize system throughput, reduce system cost, reduce cost per substrate during processing, increase system reliability, improve the device yield on the processed substrates, and reduce system footprint. In one embodiment, the cluster tool is adapted to perform a wet/clean process sequence in which various substrate cleaning processes are performed on a substrate in the cluster tool.

FIGS. 1-12illustrate some of the various robot and process chamber configurations that may be used in conjunction with various embodiments of this invention. The various embodiments of the cluster tool10generally utilize one or more robot assemblies that are configured to transfer substrates between the various processing chambers retained in the processing racks (e.g., elements60,80, etc.) so that a desired processing sequence can be performed on the substrates. In one embodiment, as shown inFIGS. 1-2, the processing configuration contains one robot assembly11that is adapted to move a substrate in a vertical (hereafter the z-direction) and horizontal directions, i.e., transfer direction (x-direction) and a direction orthogonal to the transfer direction (y-direction), so that the substrates can be processed in various processing chambers retained in the processing racks (e.g., elements60and80) which are aligned along the transfer direction. The various embodiments described herein are generally configured to minimize and control the particles generated by the substrate transferring mechanisms, to prevent device yield and substrate scrap problems that can affect the CoO of the cluster tool. Another advantage of this configuration is the flexible and modular architecture allows the user to configure the number of processing chambers, processing racks, and processing robots required to meet the throughput needs of the user. WhileFIGS. 1-2illustrate one embodiment of a robot assembly11that can be used to carryout various aspects of the invention, other types of robot assemblies11may be adapted to perform the same substrate transferring and positioning function(s) without varying from the basic scope of the invention.

The present invention generally provides an apparatus and method for processing substrates in a cluster tool that has the capability of performing substrate processing steps simultaneously on multiple substrates that are processed in a single substrate fashion. In one embodiment, each of the described chambers/methods performs wet processing steps, such as but not limited to etching, cleaning, rinsing and/or drying of a single substrate in a single substrate processing chamber. In one embodiment, multiple cleaning process steps are performed on multiple substrates that are each positioned in multiple single substrate processing chambers simultaneously. The advantageous process sequence improves the substrate throughput, and reduces system complexity, process variability and chemical waste concerns commonly found when trying to wet process multiple substrates separately in a single substrate processing chamber. The embodiments described herein also improve the process results commonly found in conventional batch processing configurations, since the use of multiple single-substrate processing chambers are better able to control the key substrate processing variables on each substrate during the substrate processing steps. Such process chambers and methods are beneficial in that each substrate is exposed to the same process conditions to which the other substrates undergoing the same process are exposed. This yields higher precision processing than seen in a batch system, in which a substrate positioned in one part of a substrate batch may be exposed to slightly different process conditions (such as fluid flow conditions, chemical concentrations, temperatures, etc.) than a substrate positioned in a different part of the batch. For example, a substrate at the end of a batch containing a longitudinal array of substrates may see different conditions than a substrate at the center of the same array. Such variations in conditions can yield batches lacking in wafer-to-wafer uniformity.

Single substrate chambers/methods such as those described herein are further beneficial in that each substrate is exposed to process fluids for a shorter amount of time than is required in batch processing. Moreover, the chambers/methods described herein can be practiced using the same or smaller volumes of process fluids (on a substrate-per-substrate basis) than would be used in corresponding batch processes.

Cluster Tool Configuration

A. System Configuration

FIG. 1Ais an isometric view of one embodiment of a cluster tool10that illustrates a number of the aspects of the present invention that may be used to advantage.FIG. 1Aillustrates an embodiment of the cluster tool10which contains a single robot that is adapted to access the various process chambers that positioned in a first processing rack60and a second processing rack80.FIG. 1Bis a plan view of the embodiment of the cluster tool10shown inFIG. 1A. One embodiment of the cluster tool10, as illustrated inFIGS. 1A and 1B, contains a front end module24and a central module25. The central module25generally contains the first processing rack60, the second processing rack80, and one or more robot assemblies11. The first processing rack60and a second processing rack80contain various processing chambers (e.g., process chambers30(FIG. 1B)) that are adapted to perform the various processing steps found in a substrate processing sequence.

The front end module24generally contains one or more pod assemblies105(e.g., items105A-D) and a front end robot assembly15(FIG. 1B). The one or more pod assemblies105, or front-end opening unified pods (FOUPs), are generally adapted to accept one or more cassettes106that may contain one or more substrates “W”, or wafers, that are to be processed in the cluster tool10. In one embodiment, the cassettes are adapted to retain the one or more substrates in horizontal orientation (i.e., processing surface, or surface on which the semiconductor devices are formed, is facing up or facing down). In one aspect, the front end module24also contains one or more pass-through positions9that allow the front end robot assembly15and the one or more robot assembly11in the central module25to exchange substrates.

The first processing rack60and second processing rack80may contain one or more modules70A-70C that contain process chambers and/or the process chamber support hardware.FIGS. 1C and 1Dillustrate side views of one embodiment of the first processing rack60and second processing rack80as viewed when facing the first processing rack60and second processing racks80from outside of the cluster tool10. The first processing rack60and second processing rack80generally contain one or more processing chambers that are adapted to perform some desired semiconductor or flat panel display device fabrication processing steps on a substrate. For example, inFIGS. 1B and 1Cthe first process rack60contains three processing chambers. In one embodiment, these device fabrication processing steps may include cleaning a surface of the substrate, etching a surface of the substrate, or exposing the substrate to some form of radiation to cause a physical or chemical change to one or more regions on the substrate. In one embodiment, the first processing rack60and second processing rack80have one or more processing chambers contained in them that can be adapted to perform one or more cleaning processing sequence steps. Examples of a processing chambers and or systems that may be adapted to perform one or more cleaning processes on a substrate and may be adapted to benefit one or more aspects of the invention is further described in the commonly assigned United States Patent Publication No. 2002/0029788, filed Jun. 25, 2001 and United States Patent Publication No. 2003/0045098, filed Aug. 31, 2001 and, which are hereby incorporated by reference in its entirety to the extent not inconsistent with the claimed invention.

FIGS. 1B,1C and1D illustrate one embodiment of the cluster tool10that has a first processing rack60and a second processing rack80that each contain two processing chamber arrays32that contain a total of three process chambers30. Generally, the processing racks60and80may contain on or more modules (e.g., reference numerals70A-70C) that either contain processing chambers or supporting equipment. In the configuration shown, modules70A and70C each contain three process chambers30that are positioned along a desirable direction (i.e., X-direction) and module70B contains the process supporting components, such as the fluid deliver systems40and41. The orientation, positioning, type and number of process chambers shown in theFIGS. 1B-Dare not intended to be limiting as to the scope of the invention, but are intended to illustrate an embodiment of the invention.

Referring toFIG. 1B, in one embodiment, the front end robot assembly15is adapted to transfer substrates between a cassette106mounted in a pod assembly105(see elements105A-D) and the one or more of the pass-through positions9. The front end robot assembly15generally contains a horizontal motion assembly15A and a robot15B, which in combination are able to position a substrate in a desired horizontal and/or vertical position in the front end module24or the adjoining positions in the central module25. The front end robot assembly15is adapted to transfer one or more substrates using one or more robot blades15C, by use commands sent from a system controller101(discussed below). In one sequence the front end robot assembly15is adapted to transfer a substrate from the cassette106to the pass-through positions9. Generally, a pass-through position is a substrate staging area that may contain a pass-through processing chamber that is similar to a conventional substrate cassette106, which is able to accept one or more substrates from a front end robot15B so that it can be removed and repositioned by the robot assembly11.

A system controller101is used to control the front-end robot15, the first robot assembly11and other supporting hardware so that substrate can be transferred to the various processing chambers contained in the first processing rack60and the second processing rack80. In one embodiment, the modules70A and70C each contain a chamber pass-through assembly34that is adapted to interface with the robot assembly11and the actuator assembly50. In this configuration, as shown inFIG. 1BandFIGS. 1E-1F, the substrates are transferred from the pass-through position9by the robot assembly11to a chamber pass-through assembly34. The robot assembly11is adapted to transfer substrates and position substrates in a horizontal, vertical, or angular orientation so as to facilitate the transfer between various positions within the cluster tool10. The ability to position and angularly orient a substrate using a robot assembly11is generally completed by cooperative movement of the components contained in the horizontal motion assembly90, vertical motion assembly95, and robot hardware assembly85, supinating robot blade assembly1100by use of commands sent from the system controller101. In one aspect, the side60B of the first processing rack60, and the side80A of the second processing rack80are both aligned along a direction parallel to the horizontal motion assembly90(described below) of each of the various robot assemblies.

The actuator assembly50, which is positioned so that it can communicate with the chamber pass-through assemblies34, is adapted to position a substrate in a processing chamber30. Therefore, the robot assembly11is adapted to pick-up, transfer and receive substrates from each of the chamber pass-through supports35contained in the chamber pass-through assembly34so that the end-effector assembly52in the actuator assembly50can pickup and position a substrate in the processing chamber30. In one aspect, the transferring process the robot assembly11is adapted to deposit a substrate in position36A (FIG. 1H) of the chamber pass-through35before it is picked-up and positioned in the process chamber30by the end-effector assemblies52.

The system controller101is adapted to control the position and motion of the various components used to complete the transferring process. The system controller101is generally designed to facilitate the control and automation of the overall system and typically includes a central processing unit (CPU) (not shown), memory (not shown), and support circuits (or I/O) (not shown). The CPU may be one of any form of computer processors that are used in industrial settings for controlling various system functions, chamber processes and support hardware (e.g., detectors, robots, motors, fluid delivery hardware, gas sources hardware, etc.) and monitor the system and chamber processes (e.g., chamber temperature, process sequence throughput, chamber process time, I/O signals, etc.). The memory is connected to the CPU, and may be one or more of a readily available memory, such as random access memory (RAM), read only memory (ROM), floppy disk, hard disk, or any other form of digital storage, local or remote. Software instructions and data can be coded and stored within the memory for instructing the CPU. The support circuits are also connected to the CPU for supporting the processor in a conventional manner. The support circuits may include cache, power supplies, clock circuits, input/output circuitry, subsystems, and the like. A program (or computer instructions) readable by the system controller101determines which tasks are performable on a substrate. Preferably, the program is software readable by the system controller101, which includes code to perform tasks relating to monitoring and execution of the processing sequence tasks and various chamber process recipe steps (e.g., SeeFIGS. 1E and 1F).

FIGS. 1G and 1Hare isometric views of one embodiment of a processing chamber array32that may be found in one or more of the modules70A-70C in the first processing rack60or second processing rack80. In one embodiment, the processing chamber array32contains three processing chambers30, a chamber pass-through assembly34that contains three chamber pass-throughs35, and an actuator assembly50that has three end-effector assemblies52. In one example, as shown inFIG. 1B, the three processing chambers30in the processing chamber array32are aligned along the X-direction. An end-effector support51A on each of the three end-effector assemblies52are adapted receive a substrate from an input slot36A or an output slot36B formed on a chamber pass-through35. The end-effector assembly51is then adapted to position the substrates in the processing chambers30. The chamber pass-through assembly34may have an actuator37(e.g., DC servomotor, linear motor, air cylinder) and linear slide38that are adapted to support, guide and position the three chamber pass-throughs35in a position relative to the end-effector assemblies52and the robot assembly11by use of commands from the system controller101(FIG. 1B). The actuator assembly50may have an actuator54(e.g., DC servomotor, linear motor) that is coupled to a slide assembly55that are adapted to support, guide and position the three end-effector assemblies52in a position relative to the chamber pass-throughs35and the processing chambers30by use of the controller101(FIG. 1B).

B. Transfer Sequence Example

FIG. 1Eillustrates one example of a substrate processing sequence500through the cluster tool10, where a number of process steps (e.g., elements501-512) may be performed after each of the transferring steps A1-A8, B1and B2have been completed by the robot assembly11or the chamber pass-through assembly34, respectively. One or more of the process steps501-512may entail performing one or more fluid processing steps on a substrate to clean a surface of the substrate, to etch a surface of the substrate, to deposit a material on a surface of the substrate, or to exposing the substrate to some form of radiation to cause a physical or chemical change to one or more regions on the substrate. An example of a typical process that may be performed is a substrate clean process steps.FIG. 1Fillustrates an example of the transfer steps that a substrate may follow as it is transferred through a cluster tool that is configured as the cluster tool shown inFIG. 1Bfollowing the processing sequence500described inFIG. 1E. In this embodiment, the substrate is removed from a pod assembly105(item #105D) by the front end robot assembly15and is delivered to a chamber positioned at the pass-through position9following the transfer path A1, so that the pass-through step502can be completed on the substrate. In one embodiment, the pass-through step502entails positioning or retaining the substrate so that another robot could pickup the substrate from the pass-through position9. Once the pass-through step502has been completed, the substrate is then transferred to an input slot36A (FIG. 1H) formed in the chamber pass-through support35by the robot assembly11following the transfer path A2. A second substrate may then be transferred from the pod assembly105to an input slot36A formed in another chamber pass-through support35by following the transfer paths A1and A3, respectively. Then a third substrate is transferred from the pod assembly105to an input slot36A formed in another chamber pass-through support35by following the transfer paths A1and A4, respectively. In aspect of the invention, during the transferring steps A2, A3, and A4the substrate is rotated from a horizontal orientation to a vertical orientation by use of a supinating robot blade assembly1100(discussed below) prior to disposing the substrate in the input slots36A of each respective chamber pass-through support35.

After a desirable number of substrates are positioned on the chamber pass-through supports35the substrates are then transferred to their respective end-effector assembly52following the transfer path B1. In one embodiment, the chamber pass-through supports35are simultaneously moved and positioned so that each of the end-effector assemblies52can receive a substrate. The end-effector assemblies52are adapted to simultaneously lifts (i.e., direction “D” inFIGS. 1G-1H) the substrates from the chamber pass-through supports35and then simultaneous deposits the substrates into each of the processing chambers30. In one aspect, the chamber pass-through assembly34is adapted to transfer the substrates positioned on the chamber pass-through supports35to the end-effector assembly52and move the chamber pass-through supports35out of the way (i.e., direction “C” inFIG. 1H) prior to the substrates being deposited in the processing chambers30.

After simultaneously depositing the substrates in the processing chambers30the process step506is then performed on the substrates generally simultaneously (i.e., direction “D” inFIG. 1H). The process step506may contain multiple sub-process steps in which one or more fluid processing steps are performed on the substrate. In one embodiment, the process step506generally contains 1 to N sub-process steps (e.g., reference numeral506A), wherein N is greater than or equal to 2. The sub-process steps506A may include but is not limited to a standard clean1(SC1), a standard clean2(SC2), an RCA clean, a HF Last clean, a DI rinse, a BEOL aqueous clean, and/or a Marangoni dry type cleaning process steps. In one example, the process step506contains five sub-process steps506A that include a SC1clean step, a DI rinse step, a HF Last step, a DI rinse step and a Marangoni dry process step. In another example, the process step506contains five sub-process steps506A that include a HF Last step, a DI Rinse step, a SC1clean step, a DI Rinse step, and an enhanced Marangoni Dry (EMD) step. In one or more of sub-process steps506A one or more megasonic actuators (e.g., transducer assemblies115A-115C inFIG. 3) are used to further improve the cleaning process, such as during the enhanced Marangoni dry (EMD) process. An example of various sub-process steps506A that may be used in conjunction with one or more of the embodiments of the processing chamber30described herein are further described in the commonly assigned US Patent Publications 2004/0198051 and 2005/0223588, which are all incorporated by reference in their entirety.

Referring toFIGS. 1E and 1F, after completing the process step506the substrate is then simultaneously transferred to the pass-through supports35by the end-effector assemblies52following the transfer path B2. After the substrates are positioned on the chamber pass-through supports35the substrates are then separately transferred to pass-through chamber9, following the transfer paths A5, A6, or A7so that the pass-through step510can be completed on the substrate. In one embodiment, the pass-through step510entails positioning or retaining the substrate so that another robot could pickup the substrate from the pass-through position9. After performing the pass-through step510the substrate is then transferred by the front end robot assembly15, following the transfer path A8, to the pod assembly105D. WhileFIGS. 1E-1Fillustrate one example of a process sequence that may be used to process a substrate in a cluster tool10, process sequences and/or transfer sequences that are more or less complex may be performed without varying from the basic scope of the invention.

In one embodiment, while the process step506is being completed in the process chambers30in the module70A of the first processing rack60multiple substrates may be transferred and loaded into the process chambers30in the module70A of the second process rack80following the transfer paths A1, A9-A11and B3so that the process step506can be completed on these new substrates. The transferring process following the transfer paths A1, A9-A11and B3is completed by the front end robot assembly15, robot assembly11, chamber pass-through assembly34, and end-effector assembly50found in the module70A, respectively. After completing the process step506the substrates are transferred back to the pod105D following the transfer paths B4, A12-A14and A1, respectively.

System Configurations

The number of processing chambers30contained within the processing chamber array32and/or the number of modules (e.g., reference numerals70A,70B,70C) positioned within the cluster tool10may be advantageously selected to meet a desired substrate throughput while minimizing the system cost and complexity.FIG. 2A-2Dare plan views of multiple examples of various systems and process chamber configurations that may be advantageously used. One will note thatFIGS. 2A-2Dare similar toFIG. 1Bexcept the number and/or position of processing chambers30and chamber pass-through supports35have been changed, and thus like numbers for similar components have been used where appropriate and will not be discussed here. The various configurations illustrated herein are not intended to limiting as to the scope of the invention.

FIG. 2Ais a plan view that illustrates a cluster tool10that contains a two processing chambers30within each of the processing chamber arrays32that are positioned in the modules70A and70C in the first and second processing racks60,80. In one embodiment, the two processing chambers30are adapted to communicate with the two chamber pass-through supports35, the two end-effector assemblies52and/or the robot assembly11.

FIG. 2Bis a plan view that illustrates a cluster tool10that contains a four processing chambers30within each of the processing chamber arrays32that are positioned in the modules70A and70C in the first and second processing racks60,80. In one embodiment, the four processing chambers30are adapted to communicate with the four chamber pass-through supports35, the four end-effector assemblies52and/or the robot assembly11.

FIG. 2Cillustrates one embodiment of a cluster tool10that is similar toFIG. 1Bexcept the processing chamber array32has been removed from the module70C of the second processing rack80. This configuration may be advantageous where the addition of the process chambers30in the module70C of the second processing rack80would not help the system throughput and thus only add to the cost and complexity of the system. In one embodiment, the number of processing chambers30in each of the various modules70A-70C of one or more of the processing racks, and may be configured and tailored to meet a desired substrate throughput goal.

FIG. 2Dillustrates one embodiment of a cluster tool10that is similar toFIG. 1Bexcept the modules70C in the first processing rack60and the second processing rack80have been removed. This configuration may be advantageous where the addition of the process chambers30and modules70C will not help the system throughput and thus only add to the cost and complexity of the system.

Process Chamber Design

The processing chambers30and methods of the present invention may be configured to perform substrate surface cleaning/surface preparation processes, such as etching, cleaning, rinsing and/or drying a single substrate. Method of processing and similar processing chambers may be found in U.S. Pat. No. 6,726,848, which issued on Apr. 27, 2004, U.S. patent application Ser. No. 11/460,049, filed Jul. 26, 2006, and U.S. patent application Ser. No. 11/445,707, filed Jun. 2, 2006, all of which are incorporated herein by reference.

FIG. 3illustrates an isometric cross sectional view of one embodiment of a substrate processing chamber30. The substrate processing chamber30comprises a chamber body101configured to retain a fluid, and an end-effector assembly52configured to transfer a substrate (not shown) into and out of the chamber body101. The chamber body101generally includes an interior volume, indicated generally as a lower chamber volume139A and an upper chamber volume139B, collectively configured as a liquid and/or a vapor processing environment. More specifically, the lower chamber volume139A is configured as a liquid processing environment, and the upper chamber volume139B is configured as a vapor processing environment.

The lower portion of the chamber body101generally comprises side walls138and a bottom wall103defining the lower chamber volume139A. The lower chamber volume139A may have a rectangular shape configured and sized to retain fluid for immersing a substrate therein. The upper chamber volume139B generally comprises a chamber lid110having an opening140formed therein, and an area below the lid110and above the lower chamber volume139A. The opening140is configured to allow the end-effector assembly52to transfer at least one substrate in and out the chamber body101. A weir117is formed on top of the side walls138to contain and allow fluid from the lower chamber volume139A to overflow. The upper portion of the chamber body101includes overflow members111and112configured to collect fluid flowing over the weir117from the lower chamber volume139A. Each of the overflow members111,112may be coupled together by a conduit (not shown), such as by a hose between overflow member112to overflow member111, that is configured to allow fluid to drain from overflow member112to overflow member111. The coupling of the overflow members111,112allows all fluid to be collected at a common location, which in this embodiment is the lower portion of overflow member111.

An inlet manifold142is formed on the sidewall138near the bottom of the lower portion of the chamber body101and is configured to fill the lower chamber volume139A with processing fluid. The inlet manifold142has a plurality of apertures141opening to the bottom of the lower chamber volume139A. An inlet assembly106having a plurality of inlet ports107is connected to the inlet manifold142. Each of the plurality of inlet ports107may be connected with an independent fluid source (e.g., fluid delivery systems40,41inFIGS. 1B and 4) by a dedicated valve (not shown), such as sources for etching, cleaning, and DI water for rinsing, such that different fluids, or a combination of fluids, may be supplied to the lower chamber volume139A for different processes.

As the processing fluid fills up the lower chamber volume139A and reaches the weir117, the processing fluid overflows from the weir117to an overflow volume113formed at least partially by the overflow members111and112. Fluid from overflow member112may be flowed to the overflow member111to a common collection point in the lower portion of overflow member111. A plurality of outlet ports114, configured to drain the collected fluid, may be formed on the overflow member111. The plurality of outlet ports114may be connected to a pump system, and in one embodiment, each of the plurality of outlet ports114may form an independent drain path dedicated to a particular processing fluid. In one embodiment, each drain path may be routed to a negatively pressurized container to facilitate rapid removal, draining, and/or recycling of the processing fluid. In one embodiment, the lower chamber volume139A may include a volume between about 1500 milliliters (mL) to about 2500 mL, for example, between about 1800 mL to about 2400 mL. In one embodiment, the lower chamber volume139A may be filled in less than about 10 seconds, for example less than about 5 seconds.

A drain assembly108may be coupled to the sidewall138near the bottom of the lower chamber volume139A that is in fluid communication with the lower chamber volume139A. The drain assembly108is configured to drain the lower processing volume139A rapidly. In one embodiment, the drain assembly108has a plurality of drain ports109, each configured to form an independent drain path dedicated to a particular processing fluid. Examples of fluid supply and drain configurations may be found in FIGS. 9-10 of U.S. patent application Ser. No. 11/445,707, filed Jun. 2, 2006, which was previously incorporated by reference.

In one embodiment of the processing chamber30, a transducer assembly115A is disposed behind or integral to a window105in the bottom wall103. The transducer assembly115A may be one or more megasonic transducers configured to provide megasonic energy to the lower processing volume139A. The transducer assembly115A may include a single transducer or an array of transducers, oriented to direct megasonic energy into the lower chamber volume139A via the window105. In another embodiment, a pair of transducer assemblies115B,115C, each of which may include a single transducer or an array of multiple transducers, are positioned behind or integral to windows105at an elevation below that of the weir117, and are oriented to direct megasonic energy into an upper portion of lower chamber volume139A. The transducer assemblies115B and115C are configured to direct megasonic energy towards a front surface and a back surface of a substrate, respectively, as the substrate is positioned in the lower chamber volume139A, and may be actuated as the substrate passes through a liquid/vapor interface, generally indicated by a dashed line at143. The addition of focused megasonic energy, as well as the controlled delivery of fluid to the substrate, will provide better substrate, and substrate-to-substrate, cleanliness results than substrates processed in a batch of multiple substrates. Examples of transducer assemblies, power adjustment to transducer assemblies, angle adjustments to transducer assemblies, and substrate orientations may be found in U.S. patent application Ser. No. 11/460,054, filed Jul. 26, 2006, and U.S. patent application Ser. No. 11/460,172, filed Jul. 26, 2006, which are both incorporated by reference herein.

As shown inFIG. 3, the opening140formed in the chamber lid110, which is configured to allow the end-effector assembly52in and out the chamber body101. The end-effector assembly52comprises a pair of rods51connected to a frame127, which is coupled to an actuator54(FIG. 1H) configured to move the end-effector assembly52relative to the chamber body101. Each of the rods51have a substrate support assembly51A which contains a effector129that contains substrate supporting elements130A,130B. The substrate support assembly51A may comprise an end effector129configured to receive and secure the substrate137by an edge of the substrate. In one embodiment, the chamber lid110includes one or more inlet plenums120and one or more exhaust plenums118, which may be formed on each side of the opening140. Each exhaust plenum may contain one or more exhaust ports119.

During processing, the lower chamber volume139A may be filled with a processing liquid supplied from the inlet manifold142, and the upper chamber volume139B may be filled with a vapor coming in from the openings121disposed on the chamber lid110. The liquid/vapor interface143may be created in the chamber body101by the introduction of the vapor from the openings121. In one embodiment, the processing liquid fills up the lower chamber volume139A and overflows from the weir117, and the liquid/vapor interface143is located at substantially the same level as the upper portion of the weir117.

Also, during processing, a substrate (not shown) being processed in the substrate processing chamber100is first immersed in the processing liquid disposed in the lower chamber volume139A, and then pulled out of the processing liquid. It is desirable that the substrate is free of the processing liquid after being pulled out of the lower chamber volume139A. In one embodiment, the presence of a surface tension gradient on the substrate will naturally cause the liquid to flow away from regions of low surface tension, which may be referred to as the Marangoni effect, is used to remove the processing liquid from the substrate. The surface tension gradient may be created at the liquid/vapor interface143. In one embodiment, an IPA vapor is used to create the liquid/vapor interface143. When the substrate is being pulled out from the processing liquid in the lower chamber volume139A, the IPA vapor condenses on the liquid meniscus extending between the substrate and the processing liquid, which facilitates a concentration of IPA in the meniscus, and results in the so-called Marangoni effect.

Chemical Delivery System

In one embodiment of the invention, one or more chemical delivery systems are configured to deliver a processing solution to two or more of the processing chambers30positioned within the cluster tool10. The chemical delivery systems may be connect to all of the processing chambers30contained within each of the modules (e.g., reference numerals70A-70C), within a processing rack (e.g., reference numerals60or80), or within the cluster tool10. The one or more chemical delivery systems are advantageously used to reduce the system complexity, redundancy, cost, and waste typically experienced in systems that utilize a dedicated chemical delivery sources to each processing chamber in the system. In general the one or more chemical delivery systems, such as the first fluid deliver system40and or the second fluid delivery system41, are adapted to retain, deliver and control the concentrations of the various chemical components in a process solution (e.g., reference numeral “E”FIG. 4) that is used during one or more of the steps in the method steps500, discussed above. In one example, an SC1processing solution is delivered to two or more of the processing chambers30in one of the modules (e.g., reference numerals70A-70C) during one or more of the sub-steps506A found in step506.

FIG. 4is a schematic of one embodiment of the first fluid delivery system40that is adapted to deliver a processing solution “E” to one or more of the processing chambers30positioned in the cluster tool10. In this configuration, a pump43is adapted to deliver the processing solution “E” from the tank42to an inlet line44A that is in fluid communication with each of the processing chambers30through each of their respective chamber inlet lines44C. A chamber inlet line44C is in communication with lower chamber volume139A of a processing chamber30through an inlet port107(FIG. 3), discussed above. Each of the processing chambers30can selectively receive fluid from the inlet line44A by opening the valve44D connected to the chamber inlet line44C that are controlled by the system controller101. During processing the fluid that is delivered to the processing chamber30is returned to the tank42through the drain line47. The unused processing solution delivered to the inlet line44A by the pump is re-circulated back to the tank42through the return line44B and flow regulation valve45(e.g., back pressure valve) so that the processing solution is never stagnant and the concentration processing solution throughout the fluid delivery system is uniform. As the concentration of the various components in the processing solution due to aging, or breakdown during processing, one or more dosing sources46A,46B are used to dose, or “spike”, the processing solution to control the desired component's concentration.

In one embodiment, a fluid delivery source48is adapted to deliver an inert gas, such as nitrogen (N2) or an IPA vapor to a portion of the processing chamber30during one or more of the phases of the process performed during a processing sequence. The inert gas or IPA vapor concentration may be controlled and exhausted from the processing chamber30by use of a conventional exhaust source49and flow regulating valve (not shown).

In one embodiment, the second fluid delivery system41(not shown inFIG. 4for clarity) is configured similarly as the first fluid delivery system40and thus contains the same hardware components that are illustrated in conjunction with the first fluid delivery system40shown inFIG. 4. In this configuration, the second fluid delivery system41is communication with a second inlet port107that is connected to on the processing chamber30. The second inlet port107is different than the first inlet port107that the first fluid delivery system40is connected to on each of the processing chambers30. In this configuration the second fluid delivery system41is adapted to contain and deliver a processing solution that is different than the processing solution delivered from the first fluid delivery system40. In one example the first chemical delivery system40contains a SC1chemistry while the second fluid delivery system41contains an HF Last type chemistry, that are commonly available from Applied Materials of Santa Clara, Calif. Typically, the SC1chemistry will contain ammonium hydroxide, hydrogen peroxide, and water in a ratio of 1:2:100 (NH4OH:H2O2:H2O). The processing solution used in the HF Last process may contain HF and DI water in a concentration between about 50:1 and 500:1 (H2O:HF).

Robot Assemblies

In general the various embodiments of the cluster tool10described herein have particular advantage over prior art configurations due to the reduced cluster tool foot print created by the reduced size of the robot assemblies (e.g., element11inFIG. 5A) and a robot design that minimizes the physical encroachment of a robot into a space occupied by other cluster tool components (e.g., robot(s), process chambers) during the process of transferring a substrate. The reduced physical encroachment prevents collisions of the robot with other foreign components. While reducing the footprint of the cluster tool, the embodiments of the robot described herein, also has particular advantage due to the reduced number of axes that need to be controlled to perform the transferring motion. This aspect is important since it will improve the reliability of the robot assemblies and thus the cluster tool. The importance of this aspect may be better understood by noting that the reliability of a system is proportional to the product of the reliability of each component in the system. Therefore, a robot having three actuators that each have a 99.00% up-time is always better than a robot that has four actuators that each have a 99.00% up-time, since the system up-time for three actuators each having 99.00% up-time is 97.03% and for four actuators each having 99.00% up-time is 96.06%.

In a case where the system throughput is robot limited, the maximum substrate throughput of the cluster tool is governed by the total number of robot moves to complete the process sequence and the time it takes to make the robot move. The time it takes a robot to make a desired move is usually limited by robot hardware, distance between processing chambers, substrate cleanliness concerns, and system control limitations. Typically the robot move time will not vary much from one type of robot to another and is fairly consistent industry wide. Therefore, a cluster tool that inherently has fewer robot moves to complete the processing sequence will have a higher system throughput than a cluster tool that requires more moves to complete the processing sequence, such as cluster tools that contains multiple pass-through steps.

Various semiconductor processes are advantageously performed using a substrate in a vertical orientation, wherein the processing surface(s) of the substrate face a horizontal direction. Such processes, as discussed above, generally include cleaning processes (e.g., Marangoni drying), where insertion and removal of the substrate are critical to the performance of the process, or where the footprint of the processing apparatus is minimized by processing the substrate in a vertical orientation. As noted above, when using these processes it is common to have both horizontal and vertical substrate retaining or processing stations that require a substrate tilting devices to orient the substrate prior to completing one or more desired process sequence steps. To reduce the system complexity and improve the system reliability embodiments of the invention utilize a supinating robot blade assembly1100to support and position a substrate in a vertical, horizontal or other angular orientation during the one or more steps in the process of transferring the substrate through a cluster tool.

As noted above, conventional processes of transferring a substrate from a horizontal orientation to vertical orientation, and vice versa, can also lead to a number of device yield problems due to particles created by the positioning of the substrate on a substrate receiving surface. To eliminate the issues that arise from the handoff of a constrained substrate, and the reliability issues created by adding multiple substrate orienting mechanisms, various embodiments of the invention disclosed herein generally provide a method and apparatus to transfer a substrate in a constrained and unconstrained state in a horizontal and vertically oriented manner.FIGS. 5A-5Fillustrate one embodiment of an apparatus and method of transferring a substrate in a constrained state and then transferred to a substrate support in an unconstrained vertically oriented manner.

Cartesian Robot Configuration

FIG. 5Aillustrates one embodiment of a robot assembly11that may be used as one or more of the robot assemblies11. The robot assembly11generally contains a robot hardware assembly85, one or more vertical robot assemblies95and one or more horizontal robot assemblies90. A substrate can thus be positioned in any desired X, Y and Z position in the cluster tool10by the cooperative motion of the robot hardware assemblies85, vertical robot assemblies95, horizontal robot assemblies90, and supinating robot blade assembly1100from commands sent by the system controller101.

The robot hardware assembly85generally contains one or more transfer robot assemblies86that are adapted to retain, transfer and position one or more substrates by use of commands sent from the system controller101. In one embodiment, as shown inFIG. 5A, a single transfer robot assemblies86containing a supinating robot blade assembly1100is attached to in a robot assembly11. In one embodiment, supinating robot blade assembly1100contains a robot blade assembly900(FIG. 6A) and an actuator assembly1101that are coupled to one or more linkages and actuator components that are adapted to position a substrate in desired orientation. The supinating robot blade assembly1100is adapted to hold, or restrain, a substrate so that the accelerations experienced by a substrate during a transferring process will not cause the substrate to move from a known position on the robot blade assembly900, while allowing the substrate to be positioned and deposited on a chamber pass-through35or in a processing chamber30in a horizontal, vertical or other angular orientation. As noted above, movement of the substrate during the transferring process will generate particles and reduce the substrate placement accuracy and repeatability by the robot.

FIGS. 5A-5Gillustrate embodiments of a robot assembly11and a transfer robot assemblies86that may be adapted to support and retain a substrate “W” while it is transferred through the cluster tool10. In one embodiment, the transfer robot assemblies86shown inFIGS. 5-6are adapted to transfer substrates generally parallel to a horizontal plane, such as a plane that includes the X and Y directions (FIG. 5A), due to the motion of the various components in the transfer robot assemblies86.FIG. 5Bis a close up isometric view of the robot assembly11illustrated inFIG. 5Athat has a supinating robot blade assembly1100that is attached to a linkage1102within the transfer robot assembly86. In this configuration the transfer robot assembly86and supinating robot blade assembly1100are aligned in forward position to allow the substrate “W” to be transferred in the X or Z-directions by use of the horizontal motion assembly90and the vertical motion assembly95without the interfering with adjacent processing rack components (FIG. 1B).

FIG. 5Cillustrates an alternate embodiment of the robot hardware assembly85shown inFIG. 5Bthat contains two transfer robot assemblies86that are positioned in an opposing orientation to each other so that the supinating robot blade assembly1100can be placed a small distance apart. The configuration shown inFIG. 5C, or “over/under” type blade configuration, may be advantageous, for example, where it is desired to remove a substrate from a processing chamber prior to placing the next substrate to be processed in the same processing chamber, without causing the robot hardware assembly85to leave its basic position to move the “removed” substrate to another chamber (i.e., “swap” substrates). In this case it may be desirable to position a substrate “W” in the input slot36A (FIGS. 1G-1H) and then remove a substrate from the output slot36B using different robot assemblies86. In another aspect, this configuration may allow the robot to fill up all of the blades and then transfer the substrates in groups of two or more substrates to a desired location in the tool. While transfer robot assemblies86depicted inFIGS. 5B-5Care the two bar linkage type of robot, this configuration is not intended to be limiting as to the orientation and type of robot assembly that may be used in conjunction with the embodiments discussed herein. In general, the embodiment of the robot hardware assembly85that has two transfer robot assemblies86, as illustrated inFIG. 5C, will have two transfer robot assemblies86that contain the same basic components, and thus the discussion of a single transfer robot assembly86hereafter, is intended to also describe the components found in the two robot assembly aspect(s).

One advantage of the cluster tool and robot configurations illustrated inFIGS. 5-6, is that the size of the region that surrounds a transfer robot assembly86in which the robot components and substrate are free to move without colliding with other cluster tool components external to the robot assembly11, is minimized. The area in which the robot and substrate are free to move is known as the “transferring region” (reference numeral “TR” inFIG. 1B). The transferring region “TR” may generally be defined as volume (X, Y and Z directions) in which the robot is free to move while a substrate is retained on a robot blade without colliding with other cluster tool components. While the transferring region may be described as a volume, often the most important aspect of the transferring region is the horizontal area (X and Y-directions) which the transferring region occupies, since it directly affects a cluster tool's footprint and CoO. The horizontal area of the transferring region is an important factor in defining the footprint of the cluster tool, since the smaller the horizontal components of the transferring region, the closer the various robot assembly and processing racks can be placed together. One factor in the defining size of the transferring region is the need to assure that the transferring region is large enough to reduce or prevent a robot's physical encroachment into the space occupied by other cluster tool components. The embodiments described herein have particular advantage over the prior art due to the way in which the embodiments retract the robots assembly86components into the transferring region oriented along the transfer direction (X-direction) of the horizontal motion assembly90.

Two Bar Linkage Robot Assembly

FIGS. 5A and 5F, illustrates one embodiment of a two bar linkage robot305type of transfer robot assembly86that generally contains a support plate321, a first linkage310, a supinating robot assembly1100, a transmission system312(FIG. 5F), an enclosure313a motor320and a second motor371.FIG. 5Fillustrates a side cross-sectional view of one embodiment of the two bar linkage robot305type of transfer robot assembly86in which the cross-sections of each of the components are oriented so that it could be viewed in a single figure. In this configuration the transfer robot assembly86is attached to the vertical motion assembly95through the support plate321which is attached to the vertical actuator assembly560(FIG. 7A). In this configuration the supinating robot blade assembly1100is attached to the linkage1102in the two bar linkage robot305by conventional means by use of a coupling plate1105.

FIG. 5Fillustrates a side cross-sectional view of one embodiment of the two bar linkage robot305type of transfer robot assembly86. The transmission system312in the two bar linkage robot305generally contains one or more power transmitting elements that are adapted to cause the movement of the supinating robot assembly1100by motion of the power transmitting elements, such as by the rotation of motor320. In general, the transmission system312may contain conventional gears, pulleys, etc. that are adapted to transfer rotational or translation motion from one element to another. The term “gear” as used herein is intended to generally describe a component that is rotationally coupled via a belt, teeth or other typical means to a second component and is adapted to transmit motion from one element to another. In general, a gear, as used herein, may be a conventional gear type device or pulley type device, which may include but is not limited to components such as, a spur gear, bevel gear, rack and/or pinion, worm gear, timing pulley, and v-belt pulley. The transmission system312in the two bar linkage robot305generally contains two power transmitting elements that are adapted to cause the movement of the linkage1102and the supinating robot blade assembly1100by motion of the motor320and/or the second motor371. In one aspect, the transmission system312contains a first pulley system355and a second pulley system361. The first pulley system355has a first pulley358that is attached to the motor320, a second pulley356attached to the first linkage310, and a belt359that connects the first pulley358to the second pulley356, so that the motor320can drive the first linkage310. In one aspect, a plurality of bearings356A are adapted to allow the second pulley356to rotate about the axis V1of the third pulley354. In one aspect, not shown inFIG. 5F, the bearings356A are mounted on a feature formed on the support plate321rather than the third pulley354as shown inFIG. 5F.

The second pulley system361has a third pulley354that is attached to the second motor371, a fourth pulley352that is attached to the linkage1102and a belt362that connects the third pulley354to the fourth pulley352so that the rotation of the second motor371causes the linkage1102and the supinating robot blade assembly1100to rotate about the bearing axis353(pivot V2inFIG. 11A) coupled to the first linkage310. The second motor371is mounted on the support plate321. When transferring a substrate the motor320drives the first pulley358which causes the second pulley356and first linkage310to rotate, which causes the fourth pulley352to rotate due to the angular rotation of the first linkage310and belt362about the third pulley354when the second motor371is maintained at a fixed angular position. In this configuration, versus the configuration shown inFIG. 10C, the third pulley can be rotated while the motor320is rotating the first linkage310which allows the gear ratio between the third pulley354and the fourth pulley352to be varied by adjusting the relative motion between the third pulley354and the fourth pulley352. One will note that the gear ratio affects the linkage1102and the supinating robot blade assembly1100motion relative to the first linkage310. In this configuration the gear ratio is not fixed by the size of the gears, and may be changed in different parts of the robot blade transferring motion to achieve a desired robot blade transfer path. An example of single and multiple linkage types of robot assemblies86that may adapted for use with the robot assembly11are further described in the commonly assigned and copending U.S. patent application Ser. No. 11/315,984 [APPM 9540.P1], filed Dec. 22, 2005, which is incorporated by reference in its entirety herein.

FIGS.5A and5C-5E illustrate one embodiment of a supinating robot blade assembly1100that may be used with some of the embodiments described herein to support and retain a substrate “W” while it is transferred through the cluster tool10using a robot assembly11.FIG. 5Bis a close up isometric view of the robot assembly11illustrated inFIG. 5Athat has a supinating robot blade assembly1100that is attached to a linkage1102within the transfer robot assembly86. In this configuration the transfer robot assembly86and supinating robot blade assembly1100are aligned in forward position to allow the substrate “W” to be transferred in an X or Z-directions by use of the horizontal motion assembly90and the vertical motion assembly95without the interfering with adjacent processing rack components (FIG. 1B).FIG. 5Cis a close up isometric view of the robot assembly11in which the transfer robot assembly86is extended towards a position that is generally parallel to the direction in which the horizontal motion assembly is aligned (i.e., X-direction).

FIG. 5Dis a close up isometric view of a transfer robot assembly86in an extended position that is orthogonal to the direction in which the horizontal motion assembly is aligned (i.e., X-direction). In this configuration a substrate “W” that is positioned on the supinating robot blade assembly1100may be transferred to a substrate receiving surface in a desired processing chamber in a horizontal orientation.FIG. 5Dillustrates a transfer robot assembly that has a horizontally oriented supinating robot blade assembly1100that has been extended in a Y-direction by use of the various components found in the transfer robot assembly86. In this configuration, the supinating robot blade assembly1100may be first rotate about a vertical axis, such as axis V1(FIG. 5F), by use of the motor320so that the robot blade assembly900is aligned parallel to the transfer direction (Y-direction) before the various components in the transfer robot assembly86are used to extend the two bar linkage robot305components and supinating robot blade assembly1100into a desired processing chamber.

FIG. 5Eis a close up isometric view illustrating the transfer robot assembly86in the extended position shown inFIG. 5Dwith the robot blade assembly900positioned in a vertical orientation by use of the actuator assembly1101that is contained in the supinating robot blade assembly1100. In this configuration a substrate “W” that is positioned on the supinating robot blade assembly1100is transferred to a substrate receiving surface in a desired processing chamber in an angular orientation relative to a horizontal plane (i.e., substrate processing surface is face up).FIG. 5Eillustrates a substrate in a vertical orientation.

Referring toFIG. 6B, in one embodiment, the robot blade assembly900rotated (reference number “R”) about an axis V4using a rotary actuator1104. In this configuration a rotary actuator1104, which is attached to the coupling plate1105, is connected to a bracket1103that supports the robot blade assembly900so that the components in the rotary actuator1104can rotate the robot blade assembly900relative to the coupling plate1105that is attached to the linkage1102. The rotary actuator1104may be a conventional stepper motor or servomotor, which when coupled to system controller101by conventional means, can be used to control the angular position of the substrate about the axis V4.

Horizontal Motion Assembly

FIG. 6Aillustrates a cross-sectional view of one embodiment of the horizontal motion assembly90taken along a plane parallel to the Y-direction. FIG.6B is a side cross-sectional view of one embodiment of the robot assembly11illustrated inFIG. 5Athat has been cut down the length of the horizontal motion assembly90. The horizontal motion assembly90generally contains an enclosure460, an actuator assembly443and a sled mount451. The actuator assembly443generally contains at least one horizontal linear slide assembly468and a motion assembly442. The vertical motion assembly95is attached to the horizontal motion assembly90through the sled mount451. The sled mount451is a structural piece that supports the various loads created as the vertical motion assembly95is positioned by the horizontal motion assembly90. The horizontal motion assembly90generally contains two horizontal linear slide assemblies468that each have a linear rail455, a bearing block458and a support mount452that support the weight of the sled mount451and vertical motion assembly95. This configuration thus allows for a smooth and precise translation of the vertical motion assembly95along the length of the horizontal motion assembly90. The linear rail455and the bearing block458may be linear ball bearing slides or a conventional linear guide, which are well known in the art. An example of a horizontal motion assembly90that may adapted for use with the robot assembly11are further described in the commonly assigned and copending U.S. patent application Ser. No. 11/315,984 [APPM 9540.P1], filed Dec. 22, 2005, which is incorporated by reference above.

The motion assembly442generally contains sled mount451, a horizontal robot actuator367(FIGS. 5A and 6A), a drive belt440, and two or more drive belt pulleys454A that are adapted to control the position of the vertical motion assembly95along the length of the horizontal motion assembly90. In general, the drive belt440is attached to the sled mount451(e.g., bonded, bolted or clamped) to form a continuous loop that runs along the length of the horizontal motion assembly90and is supported at the ends of the horizontal motion assembly90by the two or more drive belt pulleys454A.FIG. 6Billustrates one configuration that has four drive belt pulleys454A. In one embodiment, the horizontal robot actuator367is attached to one of the drive belt pulleys454A so that rotational motion of the pulley454A will cause the drive belt440and the sled mount451, which is attached to the vertical motion assembly95, to move along the horizontal linear slide assemblies468. In one embodiment, the horizontal robot actuator367is a direct drive linear brushless servomotor, which is adapted to move the robot relative to the horizontal linear slide assembly468.

The enclosure460generally contains a base464, one or more exterior walls463and an enclosure top plate462. The enclosure460is adapted to cover and support the components in the horizontal motion assembly90, for safety and contamination reduction reasons. Since particles are generated by mechanical components that roll, slide, or come in contact with each other, it is important to assure that the components in the horizontal motion assembly90do not contaminate the substrate surface while the substrates are transferred through the cluster tool10. The enclosure460thus forms an enclosed region that minimizes the chance that particles generated inside the enclosure460will make their way to the surface of a substrate. Particulate contamination has direct effect on device yield and thus CoO of the cluster tool.

The enclosure top plate462contains a plurality of slots471that allow the plurality of support mounts452in the horizontal linear slide assemblies468to extend through the enclosure top plate462and connect to the sled mount451. In one aspect, the width of the slots471(size of the opening in the y-direction) are sized to minimize the chance of particles making their way outside of the horizontal motion assembly90.

The base464of the enclosure460is a structural member that is designed to support the loads created by the weight of the sled mount451and vertical motion assembly95, and loads created by the movement of the vertical motion assembly95. In one aspect, the base464further contains a plurality of base slots464A that are positioned along the length of the horizontal motion assembly90to allow air entering the slots471of the enclosure top plate462to exit the enclosure through the base slots464A and out the slots10B formed in the cluster tool base10A. In one embodiment of the cluster tool10, no cluster tool base10A is used and thus the horizontal motion assembly90and processing racks may be positioned on the floor of the region in which the cluster tool10is installed. In one aspect, the base464is positioned above the cluster tool base10A, or floor, by use of the enclosure supports461to provide an unrestricted and uniform flow path for air to flow through the horizontal motion assembly90. In one aspect the enclosure supports461may also be adapted to act as conventional vibration dampers. Air flow created by the environmental control assembly110or clean room environment that flows through the enclosure460in one direction, preferably downward, will help to reduce the possibility of particles generated inside the enclosure460from making its way to the substrate surface. In one aspect, the slots471formed in the enclosure top plate462and the base slots464A are designed to restrict the volume of air flowing from the environmental control assembly110so that a pressure drop of at least a 0.1″ wg is achieved between the outside of the enclosure top plate462to the interior region of the enclosure460. In one aspect, a central region430of the enclosure460is formed to isolate this region from the other parts of the horizontal motion assembly by use of the internal walls465. The addition of internal walls465can minimize recirculation of the air entering the enclosure460and acts as an air flow directing feature.

Referring toFIG. 6AandFIG. 7A, in one aspect of the enclosure460, the drive belt is positioned to form a small gap between drive belt440and the drive belt slot472formed in the enclosure top plate462. This configuration may be advantageous to prevent particles generated inside the enclosure460from making their way outside of the enclosure460.

Vertical Motion Assembly

FIGS. 7A-7Billustrate one embodiment of the vertical motion assembly95.FIG. 7Ais a plan view of the vertical motion assembly95illustrating the various aspects of the design. The vertical motion assembly95generally contains a vertical support570, vertical actuator assembly560, a fan assembly580, a support plate321, and a vertical enclosure590. The vertical support570is generally a structural member that is bolted, welded, or mounted to the sled mount451, and is adapted to support the various components found in the vertical motion assembly95.

The fan assembly580generally contains a fan582and a tube581that forms a plenum region584which is in fluid communication with the fan582. The fan582is generally a device that is adapted to impart motion to air by use of some mechanical means, for example, rotating fan blades, moving bellows, moving diaphragms, or moving close toleranced mechanical gears. The fan582is adapted to draw a negative pressure in the interior region586of the enclosure590relative to the exterior of the enclosure590by creating a negative pressure in the plenum region584which is in fluid communication with the plurality of slots585formed in the tube581and the interior region586. In one aspect, the number, size and distribution of the slots585, which may be round, oval or oblong, are designed to evenly draw air from all areas of the vertical motion assembly95. In one aspect, interior region586may also be adapted to house the plurality of cables (not shown) that are used to transfer signals between with the various robot hardware assembly85and components of vertical motion assembly95components with the system controller101. In one aspect, the fan582is adapted to deliver the air removed from the interior region586into the central region430of the horizontal motion assembly90where it is then evacuated from the horizontal motion assembly90through the base slots464A.

The vertical actuator assembly560generally contains a vertical motor507(FIGS. 6A and 7B), a pulley assembly576(FIG. 7B), and a vertical slide assembly577. The vertical slide assembly577generally contains a linear rail574and a bearing block573which are attached to the vertical support570and the motion block572of the pulley assembly576. The vertical slide assembly577is adapted to guide and provide smooth and precise translation of the robot hardware assembly85and also support the weight an loads created by the movement of the robot hardware assembly85along the length of the vertical motion assembly95. The linear rail574and the bearing block573may be linear ball bearing slides, precision shaft guiding systems, or a conventional linear guide, which are well known in the art. Typical linear ball bearing slides, precision shaft guiding systems, or a conventional linear guide can be purchased from SKF USA Inc., or the Daedal Division of Parker Hannifin Corporation of Irwin, Pa.

Referring toFIGS. 7A and 7B, the pulley assembly576generally contains a drive belt571, a motion block572and two or more pulleys575(e.g., elements575A and575B) which are rotationally attached to the vertical support570and vertical motor507so that a support plate (e.g., elements321A inFIG. 7B), and thus robot hardware assembly85, can be positioned along the length of the vertical motion assembly95. In general, the drive belt571is attached to the motion block572(e.g., bonded, bolted or clamped) to form a continuous loop that runs along the length of the vertical motion assembly95and is supported at the ends of the vertical motion assembly95by the two or more drive belt pulleys575(e.g., elements575A and575B).FIG. 7Billustrates one configuration that has two drive belt pulleys575A-B. In one aspect, the vertical motor507is attached to one of the drive belt pulley575B so that rotational motion of the pulley575B will cause the drive belt571and the support plate(s), and thus robot hardware assembly85, to move along the vertical linear slide assemblies577. In one embodiment, the vertical motor507is a direct drive linear brushless servomotor, which is adapted to move the robot hardware assembly85relative to the vertical slide assembly577and thus the drive belt571and two or more pulleys575are not required.

The vertical enclosure590generally contains one or more exterior walls591and an enclosure top592(FIG. 5A) and slot593(FIGS. 9A,12A and13A). The vertical enclosure590is adapted to cover the components in the vertical motion assembly95, for safety and contamination reduction reasons. In one aspect, the vertical enclosure590is attached and supported by the vertical support570. Since particles are generated by mechanical components that roll, slide, or come in contact with each other, it is important to assure that the components in the vertical motion assembly95do not contaminate the substrate surface while the substrates are transferred through the cluster tool10. The enclosure590thus forms an enclosed region that minimizes the chance that particles generated inside the enclosure590will make their way to the surface of a substrate. Particulate contamination has direct effect on device yield and thus CoO of the cluster tool. Therefore, in one aspect, the size of the slot593(i.e., length and width) and/or the size of the fan582(e.g., flow rate) are configured so that the number of particles that can escape from the vertical motion assembly95is minimized. In one aspect, the length (Z-direction) and width (X-direction) of the slot593and the size of the fan582are selected so that a pressure drop created between a point external to the exterior walls591and the interior region586is between about 0.02 inches of water (˜5 Pa) and about 1 inch of water (˜250 Pa). In one aspect, the width of the slot593is between about 0.25 inches and about 6 inches.

The embodiments described herein generally have advantage over the prior art designs that are adapted to lift the robot components by use of components that must fold, telescope or retract back into itself to reach their lowest position vertical position. The issue arises since the lowest position of the robot is limited by the size and orientation of the vertical motion components that must fold, telescope or retract back into itself is due to the interference of the vertical motion components. The position of the prior art vertical motion components when they cannot retract any farther is often called the “dead space,” or “solid height,” due to the fact that the lowest robot position is limited by the height of the retracted components. In general, the embodiments described herein get around this problem since the bottom of the one or more transfer robot assemblies86are not supported underneath by the components in the vertical motion assembly95and thus the lowest position is only limited by the length of the linear rail574and the size of the robot hardware assembly85components. In one embodiment, as illustrated inFIGS. 7A-7B, the robot assemblies are supported in a cantilever fashion by the support plate321that is mounted to the vertical slide assembly577. It should be noted that the configurations of the support plate321and the components in the robot hardware assembly85as shown inFIG. 5Fare not intended to be limiting to the scope of the invention described herein since the orientation of the support plate321and the robot hardware assembly85may be adjusted to achieve a desired structural stiffness, and/or desired vertical stroke of the vertical motion assembly95.

The embodiments of the vertical motion assembly95described herein also have advantage over the prior art vertical movement designs, such as ones that must fold, telescope or retract back into itself, due to the improved accuracy and/or precision of the robot hardware assembly85motion due to the constrained motion along a vertical slide assembly577. Thus, in one aspect of the invention, the motion of the robot hardware assemblies is always guided by a rigid member (e.g., vertical slide assembly577) that provides a structural stiffness and positional accuracy to the components as they move along the length of the vertical motion assembly95.

Robot Blade Hardware Configuration

FIGS. 8A-8Billustrate one embodiment of a robot blade assembly900that may be used with some of the embodiments described herein to support and retain a substrate “W” while it is transferred through the cluster tool10using a robot assembly11. In one embodiment, as shown inFIGS. 5A-5Fthe robot blade assembly900is connected to the transfer robot assembly86through the supinating robot assembly1100. The robot blade assembly900is adapted to hold, “grip”, or restrain a substrate “W” so that the accelerations experienced by a substrate during the movement of the robot assembly11and/or supinating robot assembly1100will not cause the substrate position to move from a known position on the robot blade assembly900. Movement of the substrate during the transferring process will generate particles and reduce the substrate placement accuracy and repeatability by the robot. In the worst case the accelerations can cause the substrate to be dropped by the robot blade assembly900.

The accelerations experienced by the substrate can be broken up into three components: a horizontal radial acceleration component, a horizontal axial acceleration component and a vertical acceleration component. The accelerations experienced by the substrate are generated as the substrate is accelerated or decelerated in the X, Y and Z directions during the substrate movement through the cluster tool10. Referring toFIG. 8A, the horizontal radial acceleration component and the horizontal axial acceleration component are shown as forces FAand FR, respectively. The forces experienced are related to the mass of the substrate times the acceleration of substrate minus any frictional forces created between the substrate and the robot blade assembly900components. In the embodiments described above, the radial acceleration is generally created as the substrate is being rotated into position by a transfer robot assembly86and can act in either direction (i.e., +Y or −Y directions). The axial acceleration is generally created as the substrate is positioned in the X-direction by the horizontal motion assembly90, tilting of the substrate by the supinating robot blade assembly1100, and/or by the motion of the transfer robot assembly86and can act in either direction (i.e., +X or −X directions). The vertical acceleration is generally created as the substrate is positioned in the Z-direction by the vertical motion assembly95and can act in either direction (i.e., +Z or −Z directions), tilting of the substrate by the supinating robot blade assembly1100, or cantilever induced structural vibrations.

FIG. 8Ais a schematic plan view of one embodiment of the robot blade assembly900which is adapted to support the substrate “W.” The robot blade assembly900generally contains a blade base901, an actuator910, a brake mechanism920, a position sensor930, a clamp assembly905, one or more reaction members1151(e.g., one shown), and one or more substrate support components909. The clamp assembly905generally contains a clamp plate906and one or more contact members907(i.e., two contact members shown inFIG. 8A) mounted on the clamp plate906. The clamp plate906, contact members907, support1151, and blade base901can be made from a metal (e.g., aluminum, nickel coated aluminum, SST), a ceramic material (e.g., silicon carbide), or a plastic material that will be able to reliably withstand the accelerations (e.g., 10-30 m/s2) experienced by the robot blade assembly900during the transferring process and will not generate or attract particles due to the interaction with the substrate. In one embodiment, the robot blade assembly900is connected to the linkage1102at the connection point “CP.” Referring toFIG. 5G, which is a side schematic cross-sectional view of the robot blade assembly900shown inFIG. 8A, which has been sectioned through the center of the robot blade assembly900. For clarity the components positioned behind the cross-sectional plane inFIG. 16Bhave been left out (e.g., contact members907), while the brake assembly930has been retained in this view.

Referring toFIGS. 8A and 5G, when in use the substrate “W” is pressed against the captured region1151A of the support1151by a holding force (F1) delivered to substrate “W” by the actuator910through the contact members907in the clamp assembly905. In one aspect, the contact members907are adapted to contact and urge the edge “E” of the substrate “W” against the captured region1151A. In one aspect, the holding force may be between about 0.01 and about 3 kilograms force (kgf). In one embodiment, as shown inFIG. 16A, it is desirable to distribute the contact members907an angular distance “A” apart to provide axial and radial support to the substrate as it is transferred by the robot assembly11.

The process of restraining the substrate so that it can be reliably transferred through the cluster tool10using the robot blade assembly900will generally require three steps to complete. It should be noted that one or more of the steps described below may be completed simultaneously or sequentially without varying from the basic scope of the invention described herein. Before starting the process of picking up a substrate the clamp assembly905is retracted in the +X direction (not shown). The first step starts when a substrate is picked up from a substrate supporting component (e.g., pass-through positions9inFIG. 1B) so that the substrate rests on the substrate supporting surfaces1151B and909A on the support1151and substrate support component909, respectively. Next, the clamp assembly905is then moved in the −X direction until the substrate is restrained on the robot blade assembly900by the holding force (F1) delivered to substrate “W” by the actuator910through the contact members907in the clamp assembly905and the support1151. In the last step, the clamp assembly905is then held, or “locked”, in place by the brake mechanism920to prevent the acceleration of the substrate during the transferring process from appreciably varying the holding force (F1) and thus allow the substrate to move relative to the supporting surfaces. After the brake mechanism920restrains the clamp assembly905the substrate can then be transferred to another point in the cluster tool10. To deposit a substrate to a substrate supporting components the steps described above can be completed in reverse. In one embodiment, a position sensor930is used to sense the position of the clamp plate906so that the controller101can determine the status of the blade assembly900at any time during the transferring process.

In one aspect of the robot blade assembly900, the brake mechanism920is adapted to limit the movement of the clamp assembly905in at least one direction (e.g., +X direction) during the transferring process. The ability to limit the motion of the clamp assembly905in a direction opposite to the holding force (F1) supplied by the clamp assembly905will prevent the horizontal axial acceleration(s) from causing the holding force to appreciably decrease and thus allow the substrate to move around, which may generate particles, or from being dropped by the blade assembly900during the transferring process. In another aspect, the brake mechanism920is adapted to limit the movement of the clamp assembly905in at least two directions (e.g., +X and −X directions). In this configuration, the ability to limit the motion of the clamp assembly in the directions parallel to the holding force (F1) direction will prevent the horizontal axial acceleration(s) from causing the holding force to appreciably increase, which may cause substrate breakage or chipping, or appreciably decrease, which may generate particles or cause the substrate to be dropped. One will note that the brake mechanism920may be a friction inducing device or a mechanical latching device that is adapted to restrain the clamp assembly909during the transferring process. Referring toFIG. 8B, the brake mechanism920thus can be adapted to provide a restraining force F2that is adapted to restrain the clamp assembly909during the transferring process. Examples of various robot blade assemblies, brake mechanisms and other components that may be used to restrain a substrate during processing is further described in the U.S. patent application Ser. No. 11/315,873, filed Dec. 22, 2005, and the U.S. patent application Ser. No. 11/620,606 entitled “Supinating Cartesian Robot Blade” by Jeff Hudgens et al., filed Jan. 5, 2007, which are both herein incorporated by reference in their entirety.

Supinating Blade Transfer Process and Apparatus

FIG. 8Billustrates one embodiment of a robot blade assembly900that contains a substrate retaining support1150and support1151that are adapted to retain a substrate when the robot blade assembly900is rotated at an angle relative to the horizontal.FIG. 8Bis a plan view of robot blade assembly900that contains substrate retaining support1150and support1151.FIG. 8Cis an isometric partial cross-section view of a region of the robot blade assembly900that contains the substrate retaining support1150without a substrate positioned on the substrate support components909and reaction member1150.

In one embodiment, the process of reliably transferring a substrate through the cluster tool10and depositing the substrate on a substrate support in a vertical orientation, such as to the chamber pass-through support35(FIG. 1H), may require the following steps. It should be noted that one or more of the steps described below may be completed simultaneously or sequentially without varying from the basic scope of the invention described herein. Before starting the process of picking up a substrate the clamp assembly905is retracted in the +X direction. Referring toFIGS. 8C-8D, the first step starts when a substrate is picked up from a substrate supporting component (e.g., pass-through positions9inFIG. 1B) so that the substrate rests on the substrate supporting surfaces1151B and909A on the support1151and substrate support component909, respectively. Next, the clamp assembly905is then moved in the −X direction until the substrate is restrained on the robot blade assembly900by the holding force (F1) delivered to substrate “W” by the actuator910through the contact members907in the clamp assembly905and the support1151, as shown inFIG. 8E. Next, optionally the clamp assembly905is then held, or “locked”, in place by the brake mechanism920to prevent the acceleration of the substrate during the transferring process from appreciably varying the holding force (F1) and thus allow the substrate to move relative to the supporting surfaces. After the brake mechanism920restrains the clamp assembly905the substrate can then be transferred to another point in the cluster tool10. Then, once the substrate has reached its destination the substrate the clamp assembly905is retracted in the +X direction to release and un-restrain the substrate “W”. The robot blade assembly900is then rotated to a desired angular orientation, which cause the substrate to be captured within the angled captured region1150A of the substrate retaining support1150and the captured region1151A of the support1151, as shown inFIGS. 8B and 8F. The robot blade assembly900is then moved in a desired direction (e.g., D1inFIG. 8G) to a position where the substrate “W” engages a substrate input slot36A within a chamber pass-through35, which causes the substrate “W” to become separated from the angled captured region1150A of the substrate retaining support1150and the captured region1151A of the support1151. Then the robot blade assembly900can be moved away (e.g., direction D2inFIG. 8G) from the substrate “W” so that the robot assembly11can perform some other activity. In one embodiment, to pick-up a substrate “W” the steps described above can be completed in reverse.

As discussed and shown inFIGS. 8A-8Gby use of a substrate supporting device that is coupled to the robot blade assembly, such as the angled captured region1150A of the substrate retaining support1150and the captured region1151A of the support1151, a vertically oriented and unconstrained substrate “W” can be rapidly transferred to a substrate support without the generation of particles or chipping the substrate edge. In one embodiment, as discussed herein the substrate is maintained in a constrained state, and also in a supported and unconstrained state during different parts of the substrate transferring process. In one embodiment, when a transferring process requires a substrate to be oriented in an angular orientation relative to the horizontal, the substrate can be shifted from a constrained state to a supported and unconstrained state by removing the contact between the substrate constraining components, and then tilting the substrate support so that the substrate engages and is supported by the capturing regions (e.g., reference numerals1150A and1151A). The captured region1150A and the captured region1151A may contain one or more angled, beveled or hemispherical surfaces that are able to align, support, and retain a substrate that is positioned thereon due to the force gravity. The substrate retaining support1150and support1151may contain one or more polished surfaces and compatible materials (e.g., ceramic materials, silicon carbide, glass, stainless steels) that will not be abraded by the movement of the substrate edge against the captured region1150A and the captured region1151A surfaces as the substrate is transferred to a chamber pass-through35. While the discussion herein describes the engagement of a substrate with the one or more capturing regions (e.g., reference numerals1150A,1151A) by titling the substrate in an unconstrained state from a horizontal to a vertical orientation, this configuration is not intended to be limiting as to the scope of the invention since one skilled in the art would appreciate that the substrate may also be deposited into the capturing regions while in an angled orientation as the substrate is un-gripped by the substrate supporting surfaces (e.g., clamp907, support1151) without varying from the scope of the invention described herein.

Environmental Control

FIG. 9Aillustrates one embodiment of the cluster tool10that has an attached environmental control assembly110that encloses the cluster tool10to provide controlled processing environment in which to perform the various substrate processing steps found in a desired processing sequence.FIG. 8Aillustrates the cluster tool10configuration as illustrated inFIG. 1Awith an environmental enclosure positioned above the processing chambers contained in the central module25. The environmental control assembly110generally contains a filtration units112, one or more fans (not shown), and an optional cluster tool base10A (FIG. 9B). Generally the environmental control assembly110is adapted to control the air flow rate, flow regime (e.g., laminar or turbulent flow) and particulate contamination levels in the cluster tool10. In one aspect, the environmental control assembly110may also control the air temperature, relative humidity, the amount of static charge in the air and other typical processing parameters that can be controlled by use of conventional clean room compatible heating ventilation and air conditioning (HVAC) systems. Referring toFIGS. 9A-9B, in operation the environmental control assembly110draws in air from a region outside of the cluster tool10, by use of a fan (not shown) that then sends the air through a filter111and then through the cluster tool10and out of the cluster tool10through the cluster tool base10A. In one aspect, the filter111is high efficiency particulate air (HEPA) filter. The cluster tool base10A is generally the floor, or bottom region, of the cluster tool which contains a number of slots10B (FIG. 6A) or other perforation that allow the air pushed through the cluster tool10from the fan(s) to exit the cluster tool10.

FIG. 9Billustrates a cross-sectional view of an environmental control assembly110that has an environmental control assembly110that is mounted on a cluster tool10and is viewed using a cross-sectional plane oriented parallel to the Y and Z directions (seeFIG. 1A). In this configuration the environmental control assembly110contains a cluster tool base10A, an environmental control assemblies110, a first processing rack60that extends to or above the lower surface114of the environmental control assembly110, and a second processing rack80that extends to or above the lower surface114of the environmental control assembly110. In general the environmental control assembly110will each contain one or more fans (not shown) and a filter111. In this configuration the air delivered from the environmental control assembly110into the cluster tool10vertically (element “A”), between the processing racks60,80and robot assembly11, and out the cluster tool base10A. In one aspect, the walls113are adapted to enclose and form a processing region inside the cluster tool10so that the processing environment around the processing chambers retained in the processing racks60,80can be controlled by the air delivered by the environmental control assembly110.

System Configurations

FIG. 10is a plan view of the embodiment of the cluster tool10that is similar to the embodiments illustrated inFIGS. 1B and 2Cexcept that one or more wet processing chambers, or vacuum processing chambers have been added to the cluster tool10. The additional wet processing or vacuum processing chambers generally provides additional processing capability and increases the number of front-end of the line (FEOL) cleaning processes, back-end of the line (BEOL) cleaning processes, HF Last cleaning processes, and lithography strip and clean sequences to be performed in the cluster tool10. The additional wet processing or vacuum processing chambers may include a wet processing chamber that performs an oxide etch process, an electroless deposition process, an electrochemical deposition process, a wet etching process, or a vacuum processing that performs a photoresist strip process, a chemical vapor deposition (CVD) process, an atomic layer deposition (ALD) process, a dry etching process, or other similar processing techniques. One will note thatFIG. 10is similar toFIGS. 1B-1Hand2C, and thus the components that are the same or similar to those described above have the same reference numerals and are not discussed below.

In one embodiment, as shown inFIG. 10, the cluster10contains multiple processing chambers30positioned in the modules70A, one or more supporting components positioned in the modules70B, and one or more wet processing or vacuum processing chambers positioned in the modules70C found in the first and second processing racks60,80. In one embodiment, as shown inFIG. 10, the module70C in the first processing rack60contains a wet processing chamber1201and a substrate drying chamber1202and the module70C in the second processing rack80contains two dry processing chambers1203. It should be noted that number of wet processing or dry processing chambers (e.g., reference numerals1201,1202, and1203), the position or orientation of the wet processing or dry processing chambers, the number of processing chambers30, and/or the position or orientation of the processing chambers30shown inFIG. 10is not intended to be limiting as to the scope of the invention described herein. For example, in one configuration the first processing rack contains a plurality of processing chambers30and the second process rack80contains only wet processing chambers1201, drying chambers1202and/or dry processing chambers1203. The number and type of chambers that are positioned in the cluster10is generally governed by the desired substrate throughput and possible processing sequences that will be run within the cluster tool.

In one embodiment, one or more of the modules70A-70C in the first or second processing racks contains a wet clean chamber that is adapted to process the substrate in a horizontal orientation, such as a TEMPEST™ chamber available from Applied Materials of Santa Clara, Calif. In some cases the of a horizontal orientation of the substrate during processing is advantageous, since it can allow the chemicals applied to the front or backside of the substrate, which are facing up or down, to be for the most part isolated from each other due to gravity and surface tension affects. Thus allowing two different chemistries to be delivered to each side of the substrate at the same time without diluting the processing solutions, or causing the chemicals in the processing solutions to interact.

Horizontally Oriented Wet Clean Chamber

FIG. 11illustrates one embodiment of a horizontally oriented version of a wet processing chamber1201(hereafter horizontally oriented wet-clean chamber) that may be used advantageously in the cluster tool10. The horizontally oriented wet-clean chamber may be a single-substrate cleaning chamber.FIG. 11is a cross-sectional illustration of one embodiment of wet processing chamber1201that generally contains a single-substrate cleaning chamber600. In one example, the bottom side of the substrate606(substrate bottom surface614) is exposed to cleaning, rinsing and drying chemicals (e.g., SC1, SC2, DI water). The topside of the substrate606(substrate top surface616) is not exposed to any chemicals. The substrate bottom surface614(which could be the substrate non-device side) is facing down to be exposed to the chemicals delivered from the chemical source612, while the substrate top surface616(which could the device side) is facing up and is not exposed to chemicals. In another example, both, the substrate top surface616and the substrate bottom surface614can be exposed to chemicals.

In another embodiment, the chamber600includes rotatable substrate holding bracket (bracket)648, which rotates about an axis of a rotation device649. The rotation device649can further be coupled to a conventional electric motor621which can rotate the bracket648. The chamber600also includes an access door (not shown) through which robot blade assembly900(FIGS. 5A-5F) holding the substrate606enters to place the substrate606on the bracket648. In one embodiment, the substrate606, when positioned in the bracket648, can rest on support clips610connected to the bracket648. The bracket648together with the support posts607can raise or lower the substrate606to a desirable position.

In one embodiment, the electric motor621is adapted to rotate the bracket648and the substrate606while chemicals are dispensed from below during a cleaning cycle. In another embodiment, the bracket648rotates the substrate606while chemicals are dispensed from another nozzle the top and the bottom surface of the substrate606during a cleaning cycle.

In another embodiment, the chamber600includes a platter608. The platter608is generally positioned a distance from the substrate606. The gap between the substrate606and the platter608may be in the range of approximately 1-5 millimeters (mm). Chamber600also includes a tube628connected to a through-hole (feed port)642in the platter608. During a cleaning cycle, cleaning fluids or chemicals are introduced through the tube628from a chemical source612. A nozzle617located on the over the top surface of the substrate can be used to dispense chemicals and/or DI water (reference numeral613) to the top surface of the substrate from a chemical source620. The residues and/or liquids left on the substrate after processing can be cleaned off or removed by rotating the substrate606at high speed.

In one embodiment, the chamber600further includes a filter611such as a High Efficiency Particulate Arresting (HEPA) filter or an Ultra Low Penetration Air (ULPA) filter. A downward flow of air623from the filter611and gravity can act to maintain the substrate606positioned on the posts607. In another embodiment, the chamber600does not contain a filter611, but receives clean air delivered from the environmental control assembly110(FIGS. 9A-9B).

In one embodiment of the process chamber600, the platter608has a platter top surface619and a platter bottom surface615, with a set of acoustic wave transducers609coupled to the platter top surface619. The platter top surface619can be facing the substrate606. When the substrate606is placed in the bracket648, the substrate606can be centered over and held substantially parallel to the platter608to create the gap. In this embodiment, acoustic waves or megasonic sound waves can be emitted from the platter608and be transferred to the substrate606through the cleaning fluids flowing in the gap formed between the substrate bottom surface614and the platter top surface619.

In one embodiment, the chamber600may also include other nozzles (not shown) that allow cleaning fluid to be delivered onto the substrate top surface616. Thus, a first group of chemicals can be transferred to the substrate bottom surface614while chemicals from a different source (a second group of chemicals) can be transferred to a substrate top surface616. In this embodiment, the megasonic sound waves delivered by the set of acoustic wave transducers609are also applied to the substrate top surface616through the substrate when the cleaning solution is being delivered to the substrate top surface616. An example of some exemplary horizontally oriented wet clean chambers and processes that may be used herein are further described in the commonly assigned U.S. Pat. No. 6,927,176, the US Patent Publication No. 2003/0172954, the US Patent Publication No. 2003/0192577, US Patent Publication No. 2002/0029788, and the US Patent Publication No. 2004/0127044, which are all incorporated by reference in their entirety to the extent not inconsistent with the present disclosure. A wet processing chamber1201may be a TEMPEST® chamber that is available from Applied Materials of Santa Clara, Calif.

Drying Chamber

In one embodiment, the cluster tool10contains one or more drying chambers1202that are adapted to rinse and/or dry a substrate. Examples of exemplary vapor drying processes are further described in the commonly assigned U.S. Pat. No. 6,328,814, filed Mar. 26, 1999, United States Patent Publication Number 2005/0229426, filed Oct. 20, 2005, United States Patent Publication Number 2005/0241684, filed Nov. 3, 2005, and U.S. patent application Ser. No. 10/737,732, entitled “Scrubber With Integrated Vertical Marangoni Drying”, filed Dec. 16, 2003, which is incorporated by reference in its entirety to the extent not inconsistent with the present disclosure. A drying chamber1202may be a DESICA® MARANGONI® vapor drying chamber that is available from Applied Materials of Santa Clara, Calif.

In one embodiment, the drying chamber1202is adapted to perform a vapor drying process that is typically performed after completing one or more wet processing steps, to prevent watermarks and to remove any residue on the substrate from prior processes. The vapor drying process is generally performed in a vertical orientation to assure even drying or streaking on either side of the substrate. Vapor drying may also be used in lieu of a final spin-rinse-dry prior to removing a substrate from a wet processing platform. In one embodiment, it is desirable to use a drying chamber1202in combination with a wet processing chamber1201(e.g., horizontally oriented wet clean chamber). This configuration is generally advantageous in the case where the wet processing chamber1201is horizontally oriented, since drying processes, such as a Marangoni® drying process that dries both sides of substrate, are generally not effective when completed in a horizontal orientation. In this configuration, the robot assembly11is adapted to transfer a substrate from the horizontally oriented wet clean chamber to the drying chamber1202. In one example, the robot blade assembly900is adapted to receive a substrate from a horizontally oriented wet clean chamber and deposit the substrate on the cradle36illustrated inFIG. 2Aof the United States Patent Publication Number 2005/0229426, which is incorporated by reference above, of the drying chamber1202. In one aspect the substrate receiving surface of the drying chamber1202, or cradle36, is vertically oriented.

The process of vapor drying includes introducing a surface tension-reducing volatile compound, such as a volatile organic compound (VOC), to the substrate structure. For example, a VOC may be introduced with a carrier gas (e.g., nitrogen gas) in the vicinity of the liquid adhering to a substrate structure, or Marangoni® type process. The introduction of the VOC results in surface tension gradients which cause the liquid to flow off of the substrate, leaving it dry. In one embodiment, the VOC is isopropyl alcohol (IPA). In other embodiments, the VOC may be other alcohols, ketones, ethers, or other suitable compounds.

Dry Processing Chamber

FIG. 12illustrates one embodiment of a dry processing chamber1203that may be used advantageously in the cluster tool10. In one embodiment, the dry processing chamber1203is a single-substrate vacuum compatible cleaning, deposition or thermal processing chamber. In one aspect, the dry processing chamber1203is adapted to perform a dry etch, photoresist strip, plasma clean, or other similar process. In one embodiment, the dry processing chamber1203is an AXIOM® reactor that is available from Applied Materials of Santa Clara, Calif. In general, the AXIOM® reactor is a remote plasma reactor in which the radio-frequency plasma is confined such that only reactive neutrals are allowed to enter a reaction volume of the process chamber. Such confinement scheme minimizes the plasma-related damage to the substrate or circuits formed on the substrate. In the AXIOM® reactor, a wafer backside may be heated radiantly by quartz halogen lamps or resistively heated or cooled using heat transfer (e.g., coolant circulating through the wafer support), such that the wafer temperature can be maintained at 20 to 450° C. The AXIOM® reactor is described in detail in U.S. patent application Ser. No. 10/264,664, filed Oct. 4, 2002, which is herein incorporated by reference. Examples of an exemplary dry clean process and apparatus are further described in the commonly assigned U.S. patent application Ser. No. 10/915,519, filed Aug. 10, 2004, U.S. patent application Ser. No. 11/463,429, filed Aug. 9, 2006, U.S. patent application Ser. No. 10/777,026, filed Feb. 11, 2004, which are all incorporated by reference in their entirety to the extent not inconsistent with the present disclosure.

FIG. 12illustrates a schematic diagram of the AXIOM® reactor1204that may be used in the cluster tool10. The reactor1204generally comprises a process chamber1208, a remote plasma source1206, and the system controller101. The process chamber1208generally is a vacuum vessel, which comprises a first portion1210and a second portion1212. In one embodiment, the first portion1210comprises a substrate pedestal1205, a sidewall1216and a vacuum pump1214. The second portion1212comprises a lid1218and a gas distribution plate (showerhead)1220, which defines a gas mixing volume1222and a reaction volume1224. The lid1218and sidewall1216are generally formed from a metal (e.g., aluminum (Al), stainless steel, and the like) and electrically coupled to a ground reference1260.

The substrate pedestal1205supports a substrate (wafer)1226within the reaction volume1224. In one embodiment, the substrate pedestal1205may comprise a source of radiant heat, such as gas-filled lamps1228, as well as an embedded resistive heater1230and a conduit1232. The conduit1232provides cooling water from a source1234to the backside of the substrate pedestal1205. The wafer sits on the pedestal surface. Gas conduction transfers heat from the pedestal1205to the wafer1226. The temperature of the wafer1226may be controlled between about 20 and 400° C.

The vacuum pump1214is adapted to an exhaust port1236formed in the sidewall or a bottom wall1216of the process chamber1208. The vacuum pump1214is used to maintain a desired gas pressure in the process chamber1208, as well as evacuate the post-processing gases and other volatile compounds from the chamber. In one embodiment, the vacuum pump1214comprises a throttle valve1238to control a gas pressure in the process chamber1208.

The process chamber1208also comprises conventional systems for retaining and releasing the wafer1226, detecting an end of a process, internal diagnostics, and the like. Such systems are collectively depicted inFIG. 12as support systems1240.

The remote plasma source1206comprises a power source1246, a gas panel1244, and a remote plasma chamber1242. In one embodiment, the power source1246comprises a radio-frequency (RF) generator1248, a tuning assembly1250, and an applicator1252. The RF generator1248is capable of producing of about 200 to 6000 W at a frequency of about 200 to 600 kHz. The applicator1252is inductively coupled to the remote plasma chamber1242to inductively couple RF power to process gas (or gas mixture)1264to form a plasma1262in the chamber. In this embodiment, the remote plasma chamber1242has a toroidal geometry that confines the plasma and facilitates efficient generation of radical species, as well as lowers the electron temperature of the plasma. In other embodiments, the remote plasma source1206may be a microwave plasma source, however, the stripping rates are generally higher using the inductively coupled plasma.

The gas panel1244uses a conduit1266to deliver the process gas1264to the remote plasma chamber1242. The gas panel1244(or conduit1266) comprises means (not shown), such as mass flow controllers and shut-off valves, to control gas pressure and flow rate for each individual gas supplied to the chamber1242. In the plasma1262, the process gas1264is ionized and dissociated to form reactive species.

The reactive species are directed into the mixing volume1222through an inlet port1268in the lid1218. To minimize charge-up plasma damage to devices on the wafer1226, the ionic species of the process gas1264are substantially neutralized within the mixing volume1222before the gas reaches the reaction volume1224through a plurality of openings1270in the showerhead1220.

The system controller101comprises a central processing unit (CPU)1254, a memory1256, and a support circuit1258. The CPU1254may be of any form of a general-purpose computer processor used in an industrial setting. Software routines can be stored in the memory1256, such as random access memory, read only memory, floppy or hard disk, or other form of digital storage. The support circuit1258is conventionally coupled to the CPU1254and may comprise cache, clock circuits, input/output sub-systems, power supplies, and the like.

The software routines, when executed by the CPU1254, transform the CPU into a specific purpose computer (system controller101) that controls the reactor1204such that the processes are performed in accordance with the present invention. The software routines may also be stored and/or executed by a second controller (not shown) that is located remotely from the reactor1204.