SMIF POD and wafer basket on-off state identification control method and SMIF POD and wafer basket on-off state identification control system

Abstract

The invention discloses an SMIF POD and film basket switch state identification control method and system, and the method comprises the steps: enabling an identification device to read the identification information of a film basket when the SMIF POD is turned on; generating a first data packet based on the identification information and the POD state information, and transmitting the first data packet to an upper-layer control system; analyzing the first data packet and sending an unbinding instruction; and releasing the binding relationship between the SMIF POD and the wafer basket based on the unbinding instruction. According to the judgment method, full-automatic linkage of SMIF POD box opening and closing operation and MES binding state updating is achieved, binding / unbinding omission or errors caused by negligence of manual operation are avoided, and the risk that silicon wafers are mixed by mistake due to the omission or errors is avoided.

Description

TECHNICAL FIELD

[0001] The present application belongs to the technical field of semiconductor manufacturing automation, and in particular relates to a method and system for identifying and automatically determining the binding relationship between the SMIF POD (Standard Mechanical Interface Pod) and the wafer cassette in the manufacturing of silicon wafers. BACKGROUND

[0002] With the continuous improvement of the automation level of semiconductor manufacturing plants, the overhead crane (OHT) automated material handling system has been widely used in wafer production lines to realize the unmanned transfer of wafer carriers between various process equipment. Under this background, the SMIF POD, as a closed container that can maintain a highly clean internal environment, is widely used to load and transfer wafer cassettes containing silicon wafers. However, in the actual operation of the production line, the SMIF POD and the wafer cassette need to go through multiple use, cleaning, recycling, and redistribution processes. In this process, manual intervention is inevitably required for processing, such as taking the wafer cassette out of the POD for process processing, or cleaning and maintaining the empty POD and wafer cassette. Currently, the factory management system (MES) needs to accurately track the binding relationship between the POD and the wafer cassette to ensure the correctness of the silicon wafer flow and prevent the occurrence of wrong or mixed materials. This binding and unbinding operation has traditionally relied heavily on manual operation confirmation on the MES terminal. However, when handling products and cleaning PODs and wafer cassettes, it is easy to make binding errors or forget to unbind, such as when the operator does not timely perform the unbinding operation in the MES after taking out the wafer cassette, causing the system to still consider that the wafer cassette is located in the original POD, or forgetting to perform the binding operation after placing the wafer cassette into another POD. These human errors directly lead to serious wrong or mixed material risks, affecting product yield, and even causing the entire batch of wafers to be scrapped, resulting in significant quality and economic losses to production.

[0003] Therefore, there is an urgent need for a solution that can automatically and intelligently determine the POD opening and closing state and timely and accurately update the binding relationship to eliminate human errors and ensure the smooth and reliable operation of the automated production line. SUMMARY

[0004] The present application provides a SMIF POD and wafer cassette opening and closing state identification control method and system, which overcomes the technical problem of being unable to respond to the POD opening and closing state in real time in a semiconductor overhead crane automation environment, and being prone to binding errors or forgetting to unbind, resulting in silicon wafer wrong or mixed materials.

[0005] To solve at least one of the above technical problems, the technical solution adopted by the present application is:

[0006] A SMIF POD and wafer cassette opening and closing state identification control method, comprising:

[0007] When the SMIF POD is opened, the identification device reads the wafer cassette identification information;

[0008] Based on the identification information and the POD state information, a first data packet is generated and transmitted to the upper control system;

[0009] The first data packet is parsed and an unbinding instruction is sent;

[0010] Based on the unbinding instruction, the binding relationship between the SMIF POD and the wafer cassette is released.

[0011] Further, the method further comprises:

[0012] When the SMIF POD is closed, the identification device reads the wafer cassette identification information;

[0013] Based on the identification information and the POD state information, a second data packet is generated and transmitted to the upper control system;

[0014] The second data packet is parsed and a binding instruction is sent;

[0015] Based on the binding instruction, the binding relationship between the SMIF POD and the wafer cassette is established.

[0016] Further, the wafer cassette identification information comprises:

[0017] The wafer cassette ID information stored in the RFID tag on the wafer cassette is read by the RFID reader;

[0018] And / or, the wafer cassette ID information is obtained by scanning the barcode or two-dimensional code label pasted on the wafer cassette by a barcode reader or a camera.

[0019] Further, the PLC controller of the unboxer automatically selects or simultaneously enables the RFID reader or the visual code scanning reading mode based on the wafer cassette type, wherein the wafer cassette type includes an in-house turnover wafer box and a shipment wafer box.

[0020] Further, the state information is a Lock unlocking signal when the box is opened or a Lock locking signal when the box is closed, which is generated by the PLC controller after the mechanical unlocking or locking action between the SMIF POD and the wafer cassette is completed.

[0021] Further, the upper control system is an equipment automation program (EAP) for receiving data packets from the PLC controller and generating binding or unbinding instructions recognizable by the MES system.

[0022] Further, the transmission data packet is realized by the PLC controller, which transmits the integrated data packet to the equipment automation program (EAP) through a preset communication protocol.

[0023] Further, the communication protocol comprises one of Ethernet / TCP / IP, Profinet, Mitsubishi MC protocol.

[0024] Further, the data packet is a four-tuple data composed of a timestamp, an opener ID, a lock state identifier and a wafer basket ID.

[0025] A SMIF POD and wafer basket switch state identification control system for implementing the method as described above comprises:

[0026] An opener mechanism for performing mechanical opening and closing operations of the SMIF POD;

[0027] An identification module for reading identification information of the wafer basket, at least comprising one of an RFID reader and a visual code reader;

[0028] A control transmission module for receiving action state signals of the opener mechanism and identification information read by the identification module, and integrating and packaging the information for transmission to an upper layer;

[0029] A protocol processing module for receiving data packets from the control transmission module and generating corresponding instructions;

[0030] An execution module for receiving instructions of the protocol processing module.

[0031] The SMIF POD and wafer basket switch state identification method and system designed in the present application realize full-automatic linkage of SMIF POD opening and closing operations and MES system binding state updating, completely avoid binding / unbinding omissions or errors caused by manual operation negligence, fundamentally eliminate the risk of wafer mix-up caused thereby, significantly improve the data accuracy and automation level of the production line, and reduce the quality risk and production cost. BRIEF DESCRIPTION OF DRAWINGS

[0032] Figure 1 is a flowchart of the control method in the present application;

[0033] Figure 2 is a transmission data flow direction diagram in the control method in the present application. DETAILED DESCRIPTION

[0034] The present application will be described in detail below in combination with the drawings and specific embodiments.

[0035] The present embodiment proposes a SMIF POD and wafer basket switch state identification control method, a flowchart of which is shown in Figure 1 Correspondingly, the transmission data flow direction thereof is shown in Figure 2As shown, it includes two types of actions: opening SMIF POD operation, i.e. releasing the locking relationship between the POD and the wafer basket, so that the wafer basket can be taken away; and closing SMIF POD operation, i.e. binding the relationship between the POD and the wafer basket, so that the wafer basket is locked. Based on the two actions, the corresponding identification control methods are different, which are specifically manifested as:

[0036] When the box opener performs the opening SMIF POD operation:

[0037] The robot automatically triggers the identification device to read the identification information carried on the wafer basket as soon as it opens the box cover of the POD.

[0038] Specifically, the identification information on the wafer basket is the unique ID number of the wafer basket; the identification device is an RFID reader or a visual code reader. The identification method mainly reads the wafer basket ID information stored in the RFID tag on the wafer basket through the RFID reader; and / or scans the bar code or two-dimensional code label pasted on the wafer basket through the bar code reader or camera to obtain the wafer basket ID information. That is, the wafer basket ID number in the box is automatically read out through the RFID reader or the visual code reader.

[0039] Because the box opener itself integrates sensors such as position sensors and current sensors; the PLC controller on the box opener can definitely perceive whether the mechanical action of opening the POD has been completed. After the PLC receives the signal that the action is completed, it immediately executes the pre-written program in its internal, i.e. sends a trigger signal to start working to the RFID reader or the visual code reader. After receiving the electronic signal from the PLC, the identification device starts immediately. The RFID reader starts to emit radio frequency signals and tries to receive feedback; the light of the visual code reader turns on, and the camera takes pictures and decodes. This operation completes the reading of the wafer basket ID in the short time window after the box is opened and before the wafer basket is taken away, providing a data basis for subsequent operations, and automatically reading can avoid human errors.

[0040] The identification information and the state information of the opening operation are integrated to generate a first data packet and transmitted to the upper control system.

[0041] Specifically, the reading device reads the identification information, i.e. the wafer basket ID; the sensor of the box opener feeds back the state information, and the PLC receives the two information, which will uniformly create a new data structure by binding the wafer basket ID and the disengaging mechanical action result of the box opener "opening success", and upload the two information to the EAP (equipment automation program) as the upper control system through industrial networks such as Ethernet / TCP / IP, Profinet, Mitsubishi's MC protocol, etc.

[0042] The two pieces of information must be transmitted synchronously, otherwise, the EAP as the upper system may not accurately correspond them. Especially when multiple openers work simultaneously on a high-tact production line, the EAP may receive an "opening success" signal, but does not know which box it is; or receive a wafer basket ID number, but does not know whether the wafer basket is just put in or taken out. The purpose of integration is to avoid such ambiguity and ensure one-to-one correspondence between actions and objects.

[0043] The first data packet is parsed by the upper control system, and an instruction is sent to the manufacturing execution system (MES) to release the binding relationship between the SMIF POD and the wafer basket.

[0044] Specifically, the EAP parses the first data packet received from the PLC and extracts key fields from the data packet, including opener ID, wafer basket ID, timestamp, and opening success status identifier. The EAP derives from these key information that the wafer basket and the current POD binding relationship should be released, and then generates a "unbinding" instruction understandable by the MES through the SECS / GEM standard protocol or Web API call, i.e. requests to release the relationship between the wafer basket and the current POD binding.

[0045] After receiving the "unbinding" instruction from the EAP, the MES performs an update operation in its database, i.e. finds the POD record currently bound to the wafer basket ID, and then releases the association between the two. The wafer basket is no longer located in any POD and is in a "free" state, waiting to be put into the next POD or perform other operations. From now on, the entire automatic unbinding process is successfully completed.

[0046] When the opener performs the operation of closing the SMIF POD:

[0047] The automatic triggering identification device reads the identification information carried on the wafer basket, integrates the identification information with the state information of the closing operation to generate a second data packet, and transmits it to the upper control system.

[0048] Specifically, the robot puts the wafer basket into the POD, and then the opener performs the mechanical action of "Lock" to close the SMIF POD. As with opening, when the signal that the "Lock" action is completed is received by the PLC, the PLC automatically triggers the identification device. The identification device (RFID reader or visual code reader) works again to read the identification information (ID) of the wafer basket just put into the POD.

[0049] Because the system cannot confirm that the closed cassette is the one that was previously taken out, and the re-reading can ensure that the system binds the actual cassette ID that is put into the POD, in case of misplacement, the system can also capture the correct ID, so the re-reading is a key step of the error-proofing.

[0050] After the PLC receives the read new cassette ID and the Lock locking signal, the PLC integrates the two information, packs them according to the predetermined format, and the packed information must include the time stamp, the cassette ID, the status identifier of the cassette closing operation, to form a second data packet. The PLC sends the second data packet to the EAP through the industrial network.

[0051] The second data packet is parsed by the upper control system, and an instruction for establishing the binding relationship between the SMIF POD and the cassette is sent to the manufacturing execution system (MES) accordingly.

[0052] Specifically, after receiving the second data packet, the EAP performs similar but reverse operations to processing the first data packet. That is, the cassette ID and the status identifier of the Lock being locked are parsed first; then the binding relationship between the cassette and the POD is established according to the rules. The EAP sends a binding instruction to the MES. After receiving the binding instruction, the MES associates the IDs of the POD and the cassette in the database, and records that the cassette is currently located in the POD.

[0053] By re-reading the cassette ID and associating it with the cassette closing action, all the information required for the upper system to perform the "binding" operation is provided, thereby completing the entire error-proofing and mixing closed-loop control.

[0054] In the embodiment, the PLC controller automatically selects or simultaneously enables the RFID reading and visual code scanning reading modes based on the type of the cassette, wherein the type of the cassette includes an in-house turnover cassette and a shipment cassette. The transmission step is achieved by the PLC controller, which transmits the integrated data packet to the equipment automation program (EAP) through a preset communication protocol. The upper control system is the EAP, which is used to receive the data packet from the PLC controller and generate a binding or unbinding instruction that can be recognized by the MES system.

[0055] Further, the status information of the cassette opening operation is a Lock unlocking signal, and the status information of the cassette closing operation is a Lock locking signal, which are generated by the PLC controller of the cassette opener after the mechanical unlocking or locking of the SMIF POD and the cassette is completed.

[0056] In the work, the cassette ID is automatically read by RFID or visual code scanning when the box is opened, and the PLC sends the "Lock unlocking" signal and the ID information to the EAP, and the EAP notifies the MES to release the binding between the POD and the cassette after analysis.

[0057] A SMIF POD and cassette switch state identification control system for implementing the method described above, specifically comprising:

[0058] A box opener mechanism for performing mechanical opening and closing operations of the SMIF POD;

[0059] An identification module integrated on the box opener mechanism for reading the identification information of the cassette, which at least includes one of an RFID reader and a visual code reader;

[0060] A control transmission module, which is a PLC controller, for receiving the action state signal of the box opener mechanism and the identification information read by the identification module, and integrating and packaging for transmission to the upper layer;

[0061] A protocol processing module, which is an equipment automation program EAP system, for receiving data packets from the control transmission module, performing protocol analysis and conversion, and generating corresponding binding or unbinding instructions;

[0062] An execution module, which is a manufacturing execution system MES, for receiving instructions from the protocol processing module for performing binding or unbinding operations of the SMIF POD and the cassette.

[0063] When the box opener performs physical opening (Lock unlocking) and closing (Lock locking) actions, the reading of the cassette identification information is automatically triggered, and the action state and the read information are uploaded to the equipment automation program EAP through the PLC controller, and the EAP performs protocol conversion to instruct the manufacturing execution system MES to perform corresponding binding or unbinding operations.

[0064] The SMIF POD and cassette switch state judgment method and system designed by the present application realizes full-automatic linkage of SMIF POD opening and closing operations and MES system binding state update, completely avoids binding / unbinding omissions or errors caused by human operation negligence, fundamentally eliminates the risk of wafer mixing caused thereby, significantly improves the data accuracy and automation level of the production line, and reduces the quality risk and production cost.

[0065] The above detailed description of the application has been given to understand the application better. It should not be taken as limiting the scope of the application. Any changes and improvements that anyone skilled in the art can make within the scope of the application should be deemed to fall within the scope of the patent protection of the application.

Claims

1. A method for SMIF POD and wafer basket switch status recognition control, characterized in that, The method comprises: When the SMIF POD is opened, the identification device reads the wafer cassette identification information; Based on the identification information and the POD state information, a first data packet is generated and transmitted to the upper control system; The first data packet is parsed and a disassociation instruction is sent; Based on the disassociation instruction, the binding relationship between the SMIF POD and the wafer cassette is released.

2. The method of claim 1, wherein, The method further comprises: When the SMIF POD is closed, the identification device reads the wafer cassette identification information; Based on the identification information and the POD state information, a second data packet is generated and transmitted to the upper control system; The second data packet is parsed and a binding instruction is sent; Based on the binding instruction, the binding relationship between the SMIF POD and the wafer cassette is established.

3. The method according to claim 1 or 2, characterized in that, The reading of the wafer cassette identification information comprises: The wafer cassette ID information stored in the RFID tag on the wafer cassette is read by the RFID reader; And / or, the wafer cassette ID information is obtained by scanning the bar code or two-dimensional code label pasted on the wafer cassette by the bar code reader or camera.

4. The method of claim 3, wherein, The PLC controller of the unboxer automatically selects or simultaneously enables the RFID reader or visual code scanning reading mode based on the wafer cassette type, wherein the wafer cassette type includes in-house turnover wafer boxes and shipment wafer boxes.

5. The method of claim 4, wherein, The state information is a Lock unlocking signal when the box is opened or a Lock locking signal when the box is closed, which is generated by the PLC controller after the mechanical unlocking or locking of the SMIF POD and the wafer cassette is completed.

6. The method according to claim 4 or 5, characterized in that, The upper control system is an equipment automation program (EAP) for receiving data packets from the PLC controller and generating binding or disassociation instructions recognizable by the MES system.

7. The method of claim 6, wherein, The transmission of the data packet is realized by the PLC controller, which transmits the integrated data packet to the equipment automation program (EAP) through a preset communication protocol.

8. The method of claim 7, wherein, The communication protocol includes one of Ethernet / TCP / IP, Profinet, Mitsubishi MC protocol.

9. The method according to any of claims 4-5, 7, characterized by, The data packet is a four-tuple data composed of timestamp, unboxer ID, Lock state identification and wafer cassette ID.

10. A SMIF POD and wafer basket switch status identification control system for implementing the method of any of claims 1-7, wherein, The method comprises: An unboxer mechanism for performing mechanical opening and closing operations of the SMIF POD; An identification module for reading the identification information of the wafer cassette, at least including one of an RFID reader and a visual code reader; A control transmission module for receiving the action state signal of the unboxer mechanism and the identification information read by the identification module, and integrating and packaging for transmission to the upper layer; A protocol processing module for receiving the data packet from the control transmission module and generating a corresponding instruction; An execution module for receiving the instruction of the protocol processing module.

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