1. Field
The exemplary embodiments relate to material handling systems and, more particularly, to automated material handling systems for transporting and identifying carriers in processing facilities.
2. Related Developments
Consumers continue to manifest a desire for ever more sophisticated electronic and electrical devices that are smaller in size and cheaper than current models. Manufacturers of microelectronic devices are thus under increased pressure to provide more capabilities to the devices while at the same time reducing the cost of the devices. The potential for reduction in cost of the materials used in fabricating the microelectronic devices, or in the cost related to actual fabrication of the devices is limited. However, significant cost reductions may be achieved by increasing the efficiency of the whole manufacturing process.
Automated Material Handling Systems (AMHS) have been installed in many fabrication facilities to increase manufacturing efficiency. Referring to
AMHS as described above may lack an ability to verify the identity of a lot when the lot is within the domain of the AMHS. As described above, the identification tag may only be read when the container is introduced into the system by a human operator, or when the container is introduced into the domain of the AMHS from a process tool. However, errors may occur such that the AMHS control system may register the container with an incorrect lot number. For example, a process tool may be offline when a container is loaded or the identification tag reader at the process tool may be disabled when containers are switched at the process tool. Additionally, some process tools may not have tag readers and may rely instead on a human operator typing a lot number on a keypad, which can easily result in a mistyped identifier. If a mistake is made, a container may be introduced to the AMHS with the wrong identification number, and the lot may become lost within the system. When this happens, the efficiency of the fabrication facility may certainly be effected. It may sometimes even be necessary to conduct a manual search to find a lost lot. It may therefore be desired to provide an AMHS system with verification features to ensure that a lot has not been misidentified. It may further be desired to provide an AMHS that can efficiently locate misidentified lots.
The present disclosure provides a material handling system comprising:
a controller; a transport system, the transport system comprising transport track sections and at least one transport vehicle, the at least one transport vehicle configured to move along the transport track sections and configured to transport a carrier; and at least one identification tag reader located along a particular transport track section, the at least one identification tag reader being configured to read an identification tag of the carrier being transported by the at least one transport vehicle and being further configured to send a information signal to the controller; wherein the controller is configured to verify at least a location of the carrier based on the information signal.
Implementations of the disclosure may include one or more of the following features. In some implementations, the transport track sections comprise turntables joining different transport track sections and the at least one identification tag reader is located substantially in or on the turntables. In some implementations, the at least one identification tag reader is located substantially at an end of the particular transport track section and the at least one identification tag reader is configured to read the identification tag as the carrier is being transported from a substrate processing station.
In some implementations, the material handling system comprises an automated overhead material handling system and the controller is configured to effect a recovery of a mislocated carrier when a detected position of the mislocated carrier does not match a predetermined position. In some implementations, the identification tag comprises a radio frequency identification tag.
Another aspect of the disclosure provides a material handling system comprising: a controller; a transport system, the transport system comprising transport track sections and at least one transport vehicle, the at least one transport vehicle being configured to move along the transport track sections and configured to transport a carrier; and an identification tag reader in communication with the controller and being configured to traverse the transport track sections as a unit with the at least one transport vehicle, wherein the identification tag reader is configured to read an identification tag of the carrier being transported by the at least one transport vehicle and to send a information signal to the controller; wherein the controller is configured to verify at least a location of the carrier based on the information signal.
Implementations of the disclosure may include one or more of the following features. In some implementations, the identification tag reader is located substantially in or on a particular transport vehicle and the identification tag reader is configured to read the identification tag as a respective carrier is being transported from a substrate processing station. In some implementations, the material handling system comprises an automated overhead material handling system and the controller is configured to effect a recovery of a mislocated carrier when a detected position of the mislocated carrier does not match a predetermined position.
Another aspect of the disclosure provides a method of verifying a location of a carrier payload in a material handling system, the method comprising: transporting a carrier on a transport vehicle of the material handling system; reading an identification tag of the carrier being transported by the transport vehicle; and verifying a payload of the carrier is at a predetermined position, wherein the verifying is based on reading the identification tag.
Implementations of the disclosure may include one or more of the following features. In some implementations, an identification tag reader for reading the identification tag is located along a track segment of the material handling system and an identification tag reader for reading the identification tag is located substantially in or on a turntable connecting different sections of track of the material handling system. In some implementations, an identification tag reader for reading the identification tag is configured to traverse a track of the material handling system with the transport vehicle and the identification tag of the carrier is configured to be read in a track segment of the material handling system.
In some implementations, the identification tag is configured to be read as a carrier is being transported from a substrate processing station. In some implementations, the method further comprises recovering a mislocated payload when a detected position of the mislocated payload does not match a predetermined position.
The foregoing aspects and other features of the exemplary embodiments are explained in the following description, taken in connection with the accompanying drawings, wherein:
Referring to
The exemplary embodiments described herein provide for payload identification in an Automated Material Handling System (AMHS). For example, in one exemplary embodiment suitable identification readers can be located at various points throughout the AMHS such that the readers identify, for example suitable identification features of a substrate carrier as the carrier is transported past the reader or vice versa. In other exemplary embodiments the readers of the AMHS may be mobile. For example, the identification reader may be located in or along one or more of the substrate carriers, transport vehicles, transport tracks and turntables joining the transport tracks as will be described in greater detail below. In alternate embodiments the identification reader may be located in any suitable location for obtaining the identification information from the identification tag. In one exemplary embodiment the tags may be radio frequency identification (RFID) tags. In alternate embodiments, however, the tags may be any suitable tags or indicia capable of transmitting or allowing the reading of identification information or storing identification information for retrieval by a reader.
Although the exemplary embodiments are described herein with reference to semiconductor processing for exemplary purposes only, it should be understood that the exemplary embodiments are equally applicable for the transport of any suitable items over any suitable material handling system. It is also noted that the exemplary AMHS described herein may include an overhead hoist transport system for transporting substrate carriers but that the exemplary embodiments are equally applicable to any suitable transport system including, but not limited to, for example, manually guided vehicles and automated wheeled vehicles. One example of a suitable overhead hoist transport system is the Aeroloader series of transports from Brooks Automation, Inc. Other examples of suitable overhead transports are described in U.S. Pat. Nos. 7,117,800 and 7,040,238 both of which are incorporated by reference herein in their entirety.
Still referring to
The transport system sections 215, 220, 225, 235 may be nested together (i.e. one transport loop within another transport loop) and are generally arranged to allow the high-speed transfer of, for example semiconductor workpieces, such as for example, 200 mm wafer, 300 mm wafers, 450 mm wafers, flat display panels and similar such items, to and from processing bays 220 and associated processing tools 230 in the processing facility. In alternate embodiments, any suitable material may be conveyed in the automated material handling system. The transport system 200 may also allow for the redirection of workpieces from one transport section to any another transport section. An example of an automated material handling system for transporting workpieces having interbay and intrabay branches can be found in U.S. patent application entitled “Automated Material Handling System” having Ser. No. 10/697,528, filed on Oct. 30, 2003 which is incorporated herein by reference in its entirety.
The representative configurations of the automated material handling system 200, 200′ shown in
The intrabay transport section 215, may be a modular track system that provides for the movement of any suitable workpiece transport. Each module of the track system may be provided with a suitable mating means (e.g. interlocking facets, mechanical fasteners) allowing the modules to be joined together end to end during installation of the intrabay transport sections 215. The rail modules may be provided in any suitable length, such as a few feet, or in any suitable shape, such as straight or curved, for ease of handling during installation and configuration flexibility. The track system may support the workpiece transport from beneath or in alternate embodiments, the track system may be a suspended track system. The track system may have roller bearings or any other suitable bearing surface so that the workpiece transports can move along the tracks without substantial resistance over the rollers. The roller bearing may be tapered or the tracks may be angled towards the inside of a curve or corner in the track to provide additional directional stability when the workpiece container is moving along the track.
The intrabay transport sections 215 may be any suitable transport sections including, but not limited to, a conveyor based transport system, a cable and pulley or chain and sprocket based transport system, a wheel driven system or a magnetic induction based transport system. The motor used to drive the transport system may be any suitable linear motor with an unlimited stroke capable of moving workpiece containers along the intrabay transport sections 215. The linear motor may be a solid state motor without moving parts. For example, the linear motor may be a brushed or brushless AC or DC motor, a linear induction motor, or a linear stepper motor. The linear motor may be incorporated into the intrabay transport sections 215 or into workpiece transports or containers themselves. In alternate embodiments, any suitable drive means may be incorporated to drive the workpiece transports through the intrabay transport system. In yet other alternate embodiments, the intrabay transport system may be a pathway for trackless wheeled autonomous transport vehicles.
The intrabay transport sections 215 may generally allow for uninterrupted high-speed movement or flow of the workpiece transports along the path of the intrabay transport sections 215 through the use of queue sections and shunts as described in U.S. patent application Ser. No. 11/556,584. For example, the interbay transport sections 220 may form processing or fab bays and are connected to the intrabay transport sections 215 through bay queue sections 235. The bay queue sections 235 may be located on either side of the interbay or intrabay transport sections 220, 215 and allow a workpiece container to enter the interbay transport sections 220 without stopping or slowing down the flow of material along either the intrabay transport sections 215 or the flow of material along the interbay transport sections 220. An example of a transportation system having a travel lane and an access lane allowing selectable access on and off the travel lane can be found in U.S. patent application entitled “Transportation System” with Ser. No. 11/211,236, filed on Aug. 24, 2005, which is incorporated herein by reference in its entirety. The interbay transport sections 220 and the bay queue sections 235 may have track systems that are substantially similar to that described above for the intrabay transport sections 215. In alternate embodiments, the interbay transport sections 220 and the bay queue sections 235 may have any suitable configuration, shape or form and may be driven in any suitable manner.
The interbay transport sections 220 may extend within corridors or passages connecting any number of process tools 230 to the transport system 200, 200′. The interbay transport sections 220 may also connect two or more intrabay transport sections 215 to each other as shown in
The switching of the workpiece carriers or transports from and between the different sections 215, 220, 225, 235 may be controlled by any suitable guidance or material control system connected to a controller. The guidance system may include positioning devices allowing for position determination of the transports moving along the sections 215, 220, 225, 235, 240. The positioning devices may be of any suitable type such as continuous or distributed devices, such as optical, magnetic, bar code or fiducial strips, that extend along and across the sections 215, 220, 225, 235, 240. The distributed devices may be read or otherwise interrogated by a suitable reading device located on the transport to allow the controller to establish the position of the transport on the section 215, 220, 225, 235, 240 as well as the kinematic state of the transport. Alternatively, the devices may sense and/or interrogate a sensory item on the transport to identify position/kinematics. The positioning devices may also include, alone or in combination with the distributed devices, discrete positioning devices (e.g. laser ranging device, ultrasonic ranging device, or internal positioning system akin to internal GPS, or internal reverse GPS) able to sense the position of the moving transport. The controller may combine information from the guidance system with the position feed back information from the transport to establish and maintain the transport paths of the transport along and between the sections 215, 220, 225, 235, 240.
In alternate embodiments, guidance system may include or have grooves, rails, tracks or any other suitable structure forming structural or mechanical guide surfaces to cooperate with mechanical guidance features on the workpiece transports. In still other alternate embodiments, the sections 215, 220, 225, 235, 240 may also include electrical lines, such as a printed strip or conductor providing electronic guidance for the workpiece transports (e.g. electrical lines sending a suitable electromagnetic signal that is detected by a suitable guidance system on the transports). The identification reader(s) described herein may be connected to the guidance system in any suitable manner for redirecting or otherwise processing misidentified or mislocated substrate carriers through the AMHS as will be described below. In alternate embodiments, the misidentified or mislocated substrate carriers may be redirected or otherwise processed in any suitable manner.
The AMHS may also be configured to have multiple transport paths in each of the transport segments as described in U.S. Pat. No. 6,990,721, which is incorporated herein by reference in its entirety. As will be described in greater detail below, an identification reader may be located at the beginning and/or end of each transport path to identify the contents of, for example, a substrate carrier as it enters or exits a processing bay. In one example, referring now to
As seen in
Referring now to
Referring still to
As noted above, the transport container(s) 720 may be any suitable transport containers for carrying any suitable payload including, but not limited to, front opening unified pods (FOUPS) and standard mechanical interface (SMIF) pods. In this exemplary embodiment, each of the transport containers 720 of the AMHS may be equipped with, for example, a RFID tag 721. The RFID tag may be suitably located in or on any area of the carrier that allows for the reading of the tag by, for example, a RFID reader 730. As may be realized, in alternate embodiments any suitable identification techniques may be utilized in lieu of RFID including, but not limited to, one-dimensional or multi-dimensional bar codes, infrared tags, optical character recognition (OCR) of human-readable markings, or any other suitable techniques.
The RFID tag 721 may be any suitable RFID tag including, but not limited to, passive tags, active tags or semi-passive tags. In alternate embodiments the RFID tags may be substantially similar to GPS enabled tags that can be tracked by a fabrication facility positioning system (similar to the GPS system but able to track items within the fabrication facility) where the positioning system includes readers for reading an identification of the GPS enabled tags. The RFID tag 721 may be associated with the payload or contents of a respective carrier 720 when, for example the carrier is placed into the production stream as WIP. In alternate embodiments the contents of the carrier may be associated with a respective RFID tag at any suitable point in time. The association between the RFID tags and the carrier may be made manually by, for example an operator, or automatically such as by, for example, sensors reading the RFID tag identifier and indicia on one or more content of the carrier. In alternate embodiments, the association between the RFID tag and carrier contents may be established in any suitable manner. A description of the contents and the tag identifier may be sent to, for example, the material control system 770 of the controller 760 for inclusion in an identification database. The identification database may be stored in, for example, a memory 765 of a controller, such as controller 760. In alternate embodiments the identification database may be stored in a remote location that can be remotely accessed by the controller 760 and/or the material control system 770. In alternate embodiments the content description and associated tag identifier may be sent to any suitable location for recordation. Where, for example, the carrier(s) includes semiconductor substrates, the identification database may include any suitable information such as substrate size, number of substrate in the carrier and what processing stages the substrate(s) have undergone. As may be realized, the database may be configured to include any suitable information for any suitable materials being transported in the AMHS. In one exemplary embodiment, the database may be automatically updated, for example, with respect to the production status of the content of a carrier 720 as the carrier 720 passes an RFID reader as will be described in greater detail below. In alternate embodiments, any suitable information in the database may be updated in any suitable manner.
As described above and as can be seen in
As can be seen in
Referring also to
If the content of the carrier and/or identification information matches a predetermined identification information/carrier contents in, for example, the database for a predetermined processing operation (e.g. the carrier is the carrier scheduled to be picked up), the material control system 770 may cause the vehicle 710 to transport the carrier 720 to a predetermined location including, but not limited to, processing stations and storage areas (
Referring now to
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Referring now to
In this exemplary embodiment, the diagnostic carrier 1120 may be stored in any suitable offline position when the WIP carriers, such as carrier 720A, 720B are not being scanned. In alternate embodiments, the diagnostic carrier may be stored in an online position. The storage position of the diagnostic carrier may be any suitable position that does not interfere with the flow of work through the processing facility. For example, the offline position may include, but is not limited to, a stocker, an under track storage location and a shunt or buffer of a track segment. In alternate embodiments the diagnostic carrier 1120 may be manually supplied to the vehicle 710 by an operator. In other alternate embodiments the diagnostic carrier 1120 may be supplied to the transport vehicle 710 from any suitable location and in any suitable manner. The WIP carriers 720A, 720B in this exemplary embodiment may also be stored in any suitable location such as for example, the under track storage 620, 621 shown in
Referring now to
As may be realized, the location of a respective WIP carrier within the AMHS may be determined as each WIP carrier identification information is read by the reader 1100. For example, the position of the transport vehicle 710 carrying the diagnostic carrier 1120 may be recorded and correlated to the identification data of a respective one of the WIP carriers 720A, 720B as the diagnostic carrier 1120 passes by a respective one of the WIP carriers 720A, 720B. As may also be realized the controller 760 (and the material control system 770 of the controller 760), for example, may be configured to record the position of the transport vehicle in any suitable manner. For example, in one exemplary embodiment, the sensor 1101 of the reader 100 may trigger the controller 760 to record the position of the transport vehicle 710 as the sensor 1101 detects the WIP carrier. In other exemplary embodiments, the controller 760 may be configured to record the position of a respective WIP carrier when the identification reader 1100 sends a signal to the controller 760 corresponding to the identification information read by the reader 1100. The controller may be configured to compensate for any lag time in receiving the signal as opposed to the actual time the transport vehicle passes by the WIP carrier. For example, the controller may include suitable algorithms for determining the position of the transport vehicle using, for example, information pertaining to the speed of the vehicle and the time it takes for the information signal to reach the controller. In alternate embodiments, any lag time between when the information signal is received and when the position of the transport vehicle is recorded may be compensated for in any suitable manner. As described above, the material control system 770, for example, may determine if a mismatch exists between the identified WIP carrier and a predetermined position for each respective WIP carrier by merging the identification information with the recorded position of the transport vehicle for each respective WIP carrier.
As may be realized, in this exemplary embodiment, the diagnostic carrier 1120 may be scheduled to traverse one or more sections of the AMHS track at any suitable time. For example, the AMHS may be configured to pick the diagnostic carrier 1120 and transport it past any suitable WIP any suitable number of times each day (e.g. once a day, twice a day, three times a day, etc.). In other exemplary embodiments, the AMHS may be configured to allow the diagnostic carrier 1120 to be manually picked and transported throughout the AMHS any suitable times. In alternate embodiments, any suitable number of diagnostic carriers may be transported throughout the AMHS at any suitable times. In other exemplary embodiments, if there is a mismatch found as described herein, the diagnostic carrier 1120 may be transported by each of the WIP carriers in, for example, the track segment where the mismatch was found to verify the other WIP carriers are at their predetermined positions.
In another exemplary embodiment, the diagnostic carrier 1120 may also allow for the detection of lost payloads. If for example, a mismatch is found among the WIP carriers and it is determined that a WIP carrier is lost in the AMHS, the diagnostic carrier may be deployed automatically or manually to scan, for example, the under track storage areas such as areas 620, 621 to find the lost payload. In alternate embodiments, the diagnostic carrier 1120 may scan any suitable storage locations, including but not limited to, under track storage, load ports or any other suitable area accessible to the AMHS to allow for the identification of lost payloads.
The AMHS described above having the ability to identify the material or payloads within or handled by the AMHS allows for the identification of mislocated carriers/payloads to be identified in a quick and efficient manner which may result in the prevention of lost payloads. As described above, the identification reading capability can be incorporated into any suitable area of the AMHS including, but not limited to, the transport vehicle, positioned so the transport vehicle can drive by the reader, as a payload within a carrier or otherwise incorporated into a carrier that can be transported by the transport vehicles of the AMHS. In addition diagnostic carriers can be transported throughout the AMHS in the event of a lost payload to efficiently identify the lost payload. The material control system of the controller may be configured to automatically return the mislocated carriers/payloads to a predetermined position for reinsertion into the WIP. As may be realized the reinsertion of the lost payloads/carriers may also be performed manually through the material control system.
As may also be realized, the identification of substrate cassettes during transport in the AMHS and/or while the substrate cassettes are in, for example, an under track storage area allows for reduced production times as the processing tools can process the substrates without reading an identification of a carrier interfaced with the tool, removing the carrier if the carrier is identified as the incorrect carrier and obtaining the correct carrier from somewhere within the AMHS.
It should be understood that the exemplary embodiments described herein may be employed individually or in any combination thereof. It should also be understood that the foregoing description is only illustrative of the exemplary embodiments. Various alternatives and modifications can be devised by those skilled in the art without departing from the exemplary embodiments. Accordingly, the exemplary embodiments are intended to embrace all such alternatives, modifications and variances that fall within the scope of the appended claims.