Wafer Handler Method and System
Systems and methods for handling wafers include retrieving a first wafer from a wafer cassette using a first arm, transferring the first wafer from the first transfer arm to a second arm, delivering the first wafer for processing to a process chamber using the second arm, removing the first wafer from the process chamber using the first arm, and returning the first wafer to the cassette using the first arm. The systems and methods can include retrieving a first wafer from a wafer cassette using a first arm, delivering the first wafer for processing to a process chamber using the first arm, removing a processed wafer from the process chamber using a second arm, returning the processed wafer to the cassette using the second arm, and iteratively retrieving, delivering, removing and returning wafers from the cassette while alternating arms between iterations.
This application is a divisional of, claims priority to, and incorporates by reference, the entire disclosure of U.S. patent application Ser. No. 10/687,023, filed on Oct. 16, 2003.
BACKGROUND1. Field
The disclosed methods and systems relate generally to semiconductor processing, and more particularly to wafer handling methods and systems.
2. Description of Relevant Art
Some challenges of semiconductor manufacturing include providing a manufacturing process that produces reduced process defects with increased process throughput. These manufacturing concerns can also be balanced with other requirements that include a need for reduced contamination.
Wafers from the cassettes in the left and right load locks 12, 14 can be processed in turn, alternating between left and right load locks 12, 14. Accordingly, in a system according to
For a system according to
Batch vacuum load locks such as those according to
The systems and methods disclosed herein can include wafer handling methods and systems for retrieving wafers from a storage position, delivering the wafers to a process chamber and returning the processed wafers to the storage position a method for handling wafers can include retrieving a first wafer from a wafer cassette using a first arm, transferring the first wafer from the first arm to a second arm, delivering the first wafer for processing using the second arm so as to generate a processed wafer, removing the processed wafer from processing using the first arm and returning the processed wafer to the storage position using the first arm.
The method can include delivering the first wafer using the second arm while retrieving a next wafer from the storage position using the first arm. The first wafer can be oriented prior to being transferred. The method can further include processing the first wafer in the process chamber, wherein processing can include performing photoresist, dry etch, ion implantation, chemical deposition, and/or diffusion. Processing can also include orienting the next wafer and/or transferring the next wafer from the first arm to the second arm.
The storage position can be a wafer cassette and retrieving the first wafer or returning the processed wafer can include indexing the cassette.
Returning the processed wafer using the first arm can include delivering the next wafer for processing using the second arm or placing the second arm in a standby position. Transferring the wafers between arms can include aligning the first arm and the second arm to facilitate the transfer. Transferring can include controlling an orienter to transfer the first wafer from the first arm to the second arm.
In another embodiment a method for handling wafers can include retrieving a first wafer from a wafer cassette using a first arm, transferring the first wafer from the first arm to a second arm, delivering the first wafer for processing using the second arm while retrieving a distinct next wafer from the wafer cassette using the first arm, processing the first wafer to generate a processed wafer, while transferring the next wafer from the first arm to the second arm, removing the processed wafer from processing using the first arm and delivering the next wafer for processing using the second arm while returning the processed wafer to the cassette using the first arm.
The method can include retrieving a distinct next wafer from the cassette using the first arm while processing the next wafer, and iteratively performing the processing, removing, and delivering. Processing can include performing photoresist, dry etch, ion implantation, chemical deposition, and/or diffusion. Transferring can include controlling an orienter to transfer the first wafer between the first arm and the second arm. Retrieving can include indexing the cartridge.
In a further embodiment, a method for processing wafers from two or more load locks can include processing wafers from a first wafer cassette in a first load lock, where the wafers are delivered for processing from the first wafer cassette using two arms, performing load lock processing for at least a second load lock to obtain a processed load lock while processing the wafers of the first wafer cassette, completing the processing of the first wafer cassette and processing wafers from a second wafer cassette in the processed load lock, where the wafers are delivered for processing from the second wafer cassette using two arms. The method can include performing load lock processing of the first load lock upon completion of processing of the first wafer cassette. Additionally, the method can include performing load lock processing of the first load lock upon completion of processing of the first wafer cassette, completing the processing of the second wafer cassette and processing wafers from a replacement wafer cassette in the first load lock, where the wafers are delivered for processing from the replacement wafer cassette using two arms. Performing load lock processing can include evacuating, venting, isolation, cassette removal, cassette replacement, cassette installation, and/or lock valve control.
In one embodiment a system for handling wafers can include a first arm for handling wafers, a distinct second arm for handling wafers, a first cassette of wafers and a wafer processing system.
The wafers can be delivered to the processing system from the first cassette using the first arm and the second arm, and the delivery can include individually retrieving a first wafer from the cassette using the first arm, transferring the first wafer from the first arm to the second arm, delivering the first wafer for processing by the wafer processing system using the second arm, processing the first wafer to generate a processed wafer, while retrieving a next wafer from the cassette using the first arm, transferring the next wafer to the second arm, removing the processed wafer using the first arm and delivering the next wafer for processing using the second arm, processing the next wafer to generate a processed wafer while returning the processed wafer to the cassette and iteratively performing the processing, transferring, removing, and processing to process the wafers in the cassette.
The system can include a first load lock for the first cassette, an orienter for orienting the wafers before processing and transferring the wafers between the first arm and the second arm and a platen for retrieving wafers from the second arm for delivering the wafers, and transferring processed wafers to the first arm for removing the processed wafers.
In a further embodiment a method for handling wafers can include retrieving a next wafer from a selected cassette using a first arm, transferring the next wafer to a second arm, removing a processed wafer from a process system using the first arm, delivering the next wafer to the process system using the second arm and returning the processed wafer to the selected cassette using the first arm.
In one aspect, the method can iteratively return to retrieving. Transferring can include using an orienter to transfer the next wafer. The processed wafer can be oriented before returning the processed wafer and a cassette can be selected prior to retrieving. The method can determine whether unprocessed wafers remain in the selected cassette, and, based on the determination, can select a new cassette and iteratively return to retrieving, and/or perform load lock processing associated with the processed cassette.
In one embodiment, a method for handling wafers can include retrieving a next wafer from a storage position using a first arm, removing a processed wafer from processing using a second arm, delivering the next wafer for processing, returning the processed wafer to the storage position, and iteratively performing the retrieving, delivering and returning while alternating using the first arm and the second arm between iterations. Returning can include returning while processing the next wafer in a process chamber. Processing can include performing at least one of photoresist, dry etch, ion implantation, chemical deposition, and diffusion. The method can include orienting the next wafer prior to delivering the next wafer. The storage position can be a wafer cassette, and retrieving and returning the processed wafer to the cassette can include indexing the cassette. Returning the processed wafer to the storage position using the second arm can include placing the first arm in a standby position.
In one embodiment, a method for handling wafers can include retrieving a first wafer from a wafer cassette using a first arm while removing a processed wafer from processing using a second arm, delivering the first wafer for processing, returning the processed wafer to the wafer cassette while processing the first wafer to generate a processed wafer, retrieving a next wafer from the wafer cassette using the second arm while removing the processed wafer from processing using the first arm, delivering the next wafer for processing, returning the processed wafer to the wafer cassette while processing the next wafer to generate a next processed wafer, and iteratively performing the retrieving, delivering and returning while alternating using the first arm and the second arm between iterations. The method can include orienting the first wafer prior to delivering the first wafer, and orienting the next wafer prior to delivering the next wafer. Retrieving can include indexing the cassette. Delivering the first and next wafers can include processing the first and next wafers in a process chamber and processing can include performing at least one of photoresist, dry etch, ion implantation, chemical deposition, and diffusion.
In one embodiment, a system for handling wafers can include a first arm for handling wafers, a distinct second arm for handling wafers, a first cassette of wafers, and a wafer processing system, where wafers are delivered to the processing system from the first cassette using the first arm and the second arm, and where the delivery includes, individually retrieving a first wafer from the cassette using the first arm, delivering the first wafer for processing by the wafer processing system using the first arm, returning a processed wafer to the cassette using a second arm while processing the first wafer to generate a processed wafer, retrieving a next wafer from the cassette using the second arm, removing the processed wafer using the first arm and delivering the next wafer for processing using the second arm, processing the next wafer to generate a processed wafer while returning the processed wafer to the cassette, and iteratively performing the retrieving, delivering, returning, retrieving, removing, and processing to process the wafers in the cassette.
The system can include a first load lock for the first cassette and an orienter for orienting the wafers before processing. The system can include a platen for retrieving wafers from the first and second arms for processing the wafers, and transferring processed wafers to the first and second arms for removing the processed wafers. The system can include at least one carriage for moving the first and second arms relative to the cassette for returning and retrieving wafers from the cassette.
Other objects and advantages will become apparent hereinafter in view of the specification and drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
To provide an overall understanding, certain illustrative embodiments will now be described; however, it will be understood by one of ordinary skill in the art that the systems and methods described herein can be adapted and modified to provide systems and methods for other suitable applications and that other additions and modifications can be made without departing from the scope of the systems and methods described herein.
Unless otherwise specified, the illustrated embodiments can be understood as providing exemplary features of varying detail of certain embodiments, and therefore, unless otherwise specified, features, components, modules, and/or aspects of the illustrations can be otherwise combined, separated, interchanged, and/or rearranged without departing from the disclosed systems or methods. Additionally, the shapes and sizes of components are also exemplary and unless otherwise specified, can be altered without affecting the disclosed systems or methods.
The disclosure includes wafer handling methods and systems for retrieving wafers from a wafer cassette in a load lock, delivering the wafers to a process chamber, and returning the processed wafers to the cassette. The methods and systems include a first arm and a second arm that can be coordinated to perform the retrieval, delivery, and return of wafers to allow wafers from the same cassette and/or load lock to be sequentially processed. As provided herein, sequential processing is not to be understood as implying an order of retrieval from the cassette.
Accordingly, for the disclosed methods and systems, a first arm for handling wafers can be understood to be a robotic or other mechanical, electrical, and/or electromechanical arm that may be capable of handling wafers as provided herein. The first arm can be of varying shape such as c-shaped, u-shaped, or another shape, and the methods and systems herein are not limited by a type and/or shape of arm, or a method or system by which the arm may be controlled. The methods and systems also include a second arm. Although the illustrated embodiments indicate that the second arm can be the same as the first arm, one of ordinary skill will recognize that the first arm and the second arm can have a different shape, structure, components, and methods, and may have a different controller from the first arm, although in an embodiment where different controllers may be used, such first arm and second arm controllers can be coordinated to provide a method and system as provided herein.
Although the figures presented herein illustrate two load locks referred to as left and right load locks 12, 14, the disclosed methods and systems are not so limited, and include methods and systems with one or more load locks. Further, it can be understood that for the illustrated embodiments that indicate two load locks and where the methods and systems are described relative to the left load lock 12, such methods and systems can also be applied to the right load lock 14.
The second arm 30 can be positioned in positions that include at least a standby position to allow the second arm 30 to not interfere with processing of a wafer or with the first arm's interaction with the orienter 20, an orienter position to allow the second arm 30 to interface with at least the orienter 20, and a process position to allow the second arm 30 to deliver a wafer to the process chamber 16. Accordingly, based on an embodiment, a standby position and an orienter position may be the same position for the second arm 30. One of ordinary skill thus recognizes that unlike the other arm positions described herein that can be based on, for example, the orienter, the load lock, and a platen, the standby position is not so defined and may include a number of positions, including other defined positions.
It can thus be recognized that the first arm 18 and the second arm 30 include orienter positions and process chamber positions, and as provided herein, vertical transfers of wafers between the first arm 18 and the second arm 30 can be performed while such arms 18, 30 may be maintained in such positions. Accordingly, the first arm 18 and the second arm 30 can be arranged to allow a distance that facilitates independent operation when vertically aligned, while recognizing that a reduced vertical distance between the first and second arms 18, 30 may reduce processing time to transfer wafers between the same. Although such vertical distance between such arms 18, 30 can thus vary based on system characteristics, in one embodiment, when vertically aligned, the first and second arms 18, 30 can be separated by less than approximately five-eights to one-half of one inch.
Returning again to
As one of ordinary skill in the art also recognizes, the cassette 32 can be introduced to the load lock 12 via a loading station, where the load lock can be isolated from the loading station and the process chamber 16 to allow the load lock pressure to be altered according to (e.g., to be consistent with) the pressure in the process chamber 16. For example, a vacuum or other pressure device can lower the pressure in the load lock. Once the load lock pressure is sufficiently altered, a valve 34 or other mechanism can be altered to allow at least the first arm 18 from the process chamber 16 to access the load lock 12, and specifically, wafers included in the cassette 32.
It may thus be understood that the cassette can include one or more wafers, but in an illustrative example, can include approximately twenty-five to fifty wafers. Referring to
Referring to
For the discussion herein, the “next” wafer can be understood to the be next wafer retrieved for processing, and will be referred to as the “next” wafer until the wafer is processed, whereupon such wafer can be referred to as the processed wafer.
One of ordinary skill will thus recognize that the methods of
The methods and systems are thus not specific to a certain wafer retrieval sequence, and such sequence can be based on a given system. Further, some embodiments may not process all wafers in the cassette. Additionally, although the illustrated methods and systems indicate that the first arm 18 was vertically displaced in a certain direction relative to the second arm 30, other embodiments may reverse the configuration. Similarly, other embodiments may provide for non-vertical alignment of arms 18, 30, orienter 20, and/or platen 22.
When a cassette from, for example, the left load lock 12 of
Further, it can be recognized that while the wafer processing described relative to
Those of ordinary skill will also recognize that although the methods and systems presented an embodiment where during processing of a processed wafer, a next wafer is retrieved, oriented, and transferred from the first arm to the second arm, some methods and systems may include shorter processing times such that processing may not coincide completely with retrieval, orienting, and transferral. Accordingly, in some embodiments, processing may complete before retrieval, orienting, and transferral 110, 112, 114, while in other embodiments, processing may not complete until after retrieval, orienting, and transferral 110, 112, 114, and thus may indicate a delay until removal 116 and/or a measurement or other means to indicate when processing is complete.
Referring to
Once the retrieved wafer is loaded onto platen 22, first arm 52 can return to the orienter position, or to a standby position such that the retrieved wafer can be processed 36, as previously described, while the second arm 54 can return the processed wafer to the wafer cassette 32, as illustrated in
In one embodiment, shown in
The process can be repeated, as described further below with respect to
Those of ordinary skill will also recognize that although the methods and systems presented an embodiment where during processing of a processed wafer, a processed wafer is returned, and a next wafer is retrieved and oriented, some methods and systems may include shorter processing times such that processing may not coincide completely with return, retrieval, and orienting. Accordingly, in some embodiments, processing may complete before return, retrieval, and orienting, 210, 114, 216, while in other embodiments, processing may not complete until after return, retrieval, and orienting, 210, 214, 216, and thus may indicate a delay until removal 218 and/or a measurement or other means to indicate when processing is complete.
What has thus been described are systems and methods for handling wafers that include retrieving a first wafer from a wafer cassette using a first arm, transferring the first wafer from the first transfer arm to a second arm, delivering the first wafer for processing to a process chamber using the second arm, removing the first wafer from the process chamber using the first arm, and, returning the first wafer to the cassette using the first arm.
The methods and systems described herein are not limited to a particular hardware or software configuration, and may find applicability in many computing or processing environments. For example, the control of the cassette interchanges, evacuation and venting, load lock valves, orienters, processing systems (e.g., platen, ion implantation, etc.), and the arms, can be implemented in hardware or software, or a combination of hardware and software. The methods and systems can be implemented in one or more computer programs, where a computer program can be understood to include one or more processor executable instructions. The computer program(s) can execute on one or more programmable processors, and can be stored on one or more storage medium readable by the processor (including volatile and non-volatile memory and/or storage elements), one or more input devices, and/or one or more output devices. The processor thus can access one or more input devices to obtain input data, and can access one or more output devices to communicate output data. The input and/or output devices can include one or more of the following: Random Access Memory (RAM), Redundant Array of Independent Disks (RAID), floppy drive, CD, DVD, magnetic disk, internal hard drive, external hard drive, memory stick, or other storage device capable of being accessed by a processor as provided herein, where such aforementioned examples are not exhaustive, and are for illustration and not limitation.
The computer program(s) is preferably implemented using one or more high level procedural or object-oriented programming languages to communicate with a computer system; however, the program(s) can be implemented in assembly or machine language, if desired. The language can be compiled or interpreted.
As provided herein, the processor(s) can thus be embedded in one or more devices that can be operated independently or together in a networked environment, where the network can include, for example, a Local Area Network (LAN), wide area network (WAN), and/or can include an intranet and/or the Internet and/or another network. The network(s) can be wired or wireless or a combination thereof and can use one or more communications protocols to facilitate communications between the different processors. The processors can be configured for distributed processing and can utilize, in some embodiments, a client-server model as needed. Accordingly, the methods and systems can utilize multiple processors and/or processor devices, and the processor instructions can be divided amongst such single or multiple processor/devices.
The device(s) or computer systems that integrate with the processor(s) can include, for example, a personal computer(s), workstation (e.g., Sun, HP), personal digital assistant (PDA), handheld device such as cellular telephone, laptop, handheld, or another device capable of being integrated with a processor(s) that can operate as provided herein. Accordingly, the devices provided herein are not exhaustive and are provided for illustration and not limitation.
References to “a processor” or “the processor” can be understood to include one or more processors that can communicate in a stand-alone and/or a distributed environment(s), and can thus can be configured to communicate via wired or wireless communications with other processors, where such one or more processor can be configured to operate on one or more processor-controlled devices that can be similar or different devices. Furthermore, references to memory, unless otherwise specified, can include one or more processor-readable and accessible memory elements and/or components that can be internal to the processor-controlled device, external to the processor-controlled device, and can be accessed via a wired or wireless network using a variety of communications protocols, and unless otherwise specified, can be arranged to include a combination of external and internal memory devices, where such memory can be contiguous and/or partitioned based on the application. Accordingly, references to a database can be understood to include one or more memory associations, where such references can include commercially available database products (e.g., SQL, Informix, Oracle) and also proprietary databases, and may also include other structures for associating memory such as links, queues, graphs, trees, with such structures provided for illustration and not limitation.
References to a network, unless provided otherwise, can include one or more intranets and/or the Internet.
Many additional changes in the details, materials, and arrangement of parts, herein described and illustrated, can be made by those skilled in the art. Accordingly, it will be understood that the following claims are not to be limited to the embodiments disclosed herein, can include practices otherwise than specifically described, and are to be interpreted as broadly as allowed under the law.
Claims
1. A system for handling wafers, the system comprising:
- a first arm for handling wafers,
- a distinct second arm for handling wafers,
- a first cassette of wafers, and,
- a wafer processing system,
- where wafers are delivered to the processing system from the first cassette using the first arm and the second arm, and where the delivery includes, individually retrieving a first wafer from the cassette using the first arm, transferring the first wafer from the first arm to the second arm, delivering the first wafer for processing by the wafer processing system using the second arm, processing the first wafer to generate a processed wafer, while retrieving a next wafer from the cassette using the first arm, transferring the next wafer to the second arm, removing the processed wafer using the first arm and delivering the next wafer for processing using the second arm, processing the next wafer to generate a processed wafer while returning the processed wafer to the cassette, and iteratively performing the processing, transferring, removing, and processing to process the wafers in the cassette.
2. A system according to claim 51, further including a first load lock for the first cassette.
3. A system according to claim 51, further including an orienter for orienting the wafers before processing and transferring the wafers between the first arm and the second arm.
4. A system according to claim 51, further including a platen for retrieving wafers from the second arm for delivering the wafers, and transferring processed wafers to the first arm for removing the processed wafers.
5. A system for handling wafers, the system comprising:
- a first arm for handling wafers,
- a distinct second arm for handling wafers,
- a first cassette of wafers, and,
- a wafer processing system,
- where wafers are delivered to the processing system from the first cassette using the first arm and the second arm, and where the delivery includes, individually retrieving a first wafer from the cassette using the first arm, delivering the first wafer for processing by the wafer processing system using the first arm, returning a processed wafer to the cassette using a second arm while processing the first wafer to generate a processed wafer, retrieving a next wafer from the cassette using the second arm, removing the processed wafer using the first arm and delivering the next wafer for processing using the second arm, processing the next wafer to generate a processed wafer while returning the processed wafer to the cassette, and iteratively performing the retrieving, delivering, returning, retrieving, removing, and processing to process the wafers in the cassette.
6. A system according to claim 55, further including a first load lock for the first cassette.
7. A system according to claim 55, further including an orienter for orienting the wafers before processing.
8. A system according to claim 55, further including a platen for retrieving wafers from the first and second arms for processing the wafers, and transferring processed wafers to the first and second arms for removing the processed wafers.
9. A system according to claim 55, further including at least one carriage for moving the first and second arms relative to the cassette for returning and retrieving wafers from the cassette.
Type: Application
Filed: Apr 2, 2007
Publication Date: Jul 26, 2007
Inventor: Stanley Stone (Rockport, MA)
Application Number: 11/695,310
International Classification: H01L 21/425 (20060101);