Substrate transfer system

Abstract

To provide a substrate transfer system that suppresses scratches caused by the mirror-like main surface of a substrate contacting system components during transferring.SOLUTION: A substrate transfer system comprises: system components; a transfer section for transferring the substrate relative to the system components; an imaging section for capturing both the mirror image of the system components reflected on the mirror-like main surface of the substrate as it is transferred by the transfer section and the actual image of the system components; and a determination section for performing an abnormality determination to judge whether there is an abnormality in the clearance between the main surface of the substrate and the system components based on the mirror image and the actual image captured by the imaging section.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present invention relates to a substrate transfer system. [Background technology]

[0002] 2. Description of the Related Art A substrate moving system for moving a substrate is known (see, for example, Patent Document 1). [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Application Laid-Open No. 2013-110200 Summary of the Invention [Problem to be solved by the invention]

[0004] It would be desirable for the substrate movement system described above to prevent scratches caused by contact between the mirror-like main surface of the substrate and system components during movement. To achieve this, an imaging unit could be provided, which could capture images of the substrate and system components from directly beside the substrate, and the clearance between the main surface of the substrate and the system components could be monitored based on the captured images. However, in this case, it was difficult to stably monitor the clearance due to the thinness of the substrate and the influence of reflected light, etc.

[0005] An object of the present invention is to provide a substrate movement system that can prevent the mirror-like main surface of the substrate from coming into contact with system components during movement and being damaged. [Means for solving the problem]

[0006] One aspect of the present invention is as follows.

[0007] [1] System components; a moving unit that moves the substrate relative to the system components; an imaging unit that captures a mirror image of the system component reflected on the mirror-like main surface of the substrate when the substrate is moved by the moving unit and a real image of the system component; A substrate movement system having a determination unit that performs an abnormality determination to determine whether or not there is an abnormality in the clearance between the main surface of the substrate and the system component based on the mirror image and the real image captured by the imaging unit.

[0008] [2] The substrate moving system according to [1], wherein the determination unit performs the abnormality determination based on an apparent clearance between the mirror image and the real image in the image captured by the imaging unit.

[0009] [3] The substrate movement system described in [1] or [2], wherein the judgment unit makes the abnormality judgment based on the change between the clearance calculated for the substrate as a leading substrate approaching the system component by the moving unit and the clearance calculated for the substrate as a trailing substrate approaching the system component by the moving unit after the leading substrate has retracted from the system component.

[0010] [4] The substrate transfer system according to any one of [1] to [3], further comprising a notification unit that issues a notification when it is determined that an abnormality exists by the abnormality determination.

[0011] [5] a second system component; and a second mover that moves a second substrate relative to the second system component; a second imaging unit that captures a mirror image of the second system component reflected on a mirror-like main surface of the second substrate when the second substrate is moved by the second moving unit and a real image of the second system component; the determination unit performs a second abnormality determination to determine whether or not there is an abnormality in the clearance between the main surface of the second substrate and the second system component based on the mirror image and the real image captured by the second imaging unit, The substrate transfer system according to [4], wherein the notification unit issues a notification when it is determined that an abnormality exists by the second abnormality determination. [Effects of the Invention]

[0012] According to the present invention, it is possible to provide a substrate movement system that can prevent the mirror-like main surface of the substrate from coming into contact with system components during movement and being damaged. [Brief explanation of the drawings]

[0013] [Figure 1] FIG. 2 is a top view showing a first transfer processing section of the substrate moving system according to the embodiment of the present invention. [Figure 2] 2 is a cross-sectional view taken along the line AA in FIG. 1 when a first substrate is moved onto a first transport pallet by a first moving section. [Figure 3] 2 is a schematic diagram showing an image captured by a first imaging unit shown in FIG. 1. FIG. [Figure 4] FIG. 2 is a schematic diagram illustrating the entire substrate moving system shown in FIG. [Figure 5] 4 is a graph showing an example of the relationship between apparent clearance and actual clearance in the image shown in FIG. 3. DETAILED DESCRIPTION OF THE INVENTION

[0014] Hereinafter, an embodiment of the present invention will be described with reference to the drawings.

[0015] As shown in Figures 1 to 4, in one embodiment of the present invention, a substrate moving system 1 (see Figure 4) includes a (first) system component 6A (see Figure 1) that constitutes part of the substrate moving system 1, a (first) moving unit 3A that moves a disk-shaped (first) substrate 11A relative to the system component 6A, a (first) imaging unit 7A (see Figure 1) that photographs a mirror image 12 of the system component 6A and a real image 13 of the system component 6A reflected on the mirror-like main surface of the substrate 11A when it is moved relative to the system component 6A by the moving unit 3A (see Figure 2), and a (first) abnormality judgment determination unit 8a (see Figure 4) that determines whether or not there is an abnormality in the clearance C (see Figure 2) between the main surface of the substrate 11A and the system component 6A based on the mirror image 12 and real image 13 (see Figure 3) photographed by the imaging unit 7A.

[0016] As shown in FIG. 4, in this embodiment, the substrate transfer system 1 includes a (first) transfer processing unit 2A having a (first) transfer unit 3A, a (first) transfer pallet 4A, and a (first) processing unit 5A, and a second transfer processing unit 2B having a second transfer unit 3B, a second transfer pallet 4B, and a second processing unit 5B. The (first) transfer pallet 4A includes a (first) gripper 4aA and a (first) pallet 4bA as a (first) system component 6A. The second transfer pallet 4B includes a second gripper 4aB and a second pallet 4bB as a second system component 6B. The substrate transfer system 1 also includes a third transfer processing unit 2C, a fourth transfer processing unit 2D, a fifth transfer processing unit 2E, and a sixth transfer processing unit 2F. The number of transfer processing units provided in the substrate transfer system 1 can be set as appropriate. The (first) transport processing unit 2A transports and processes the (first) substrate 11A, the second transport processing unit 2B transports and processes the second substrate 11B, the third transport processing unit 2C transports and processes the third substrate 11C, the fourth transport processing unit 2D transports and processes the fourth substrate 11D, the fifth transport processing unit 2E transports and processes the fifth substrate 11E, and the sixth transport processing unit 2F transports and processes the sixth substrate 11F.

[0017] The substrate movement system 1 has a (first) imaging unit 7A for the (first) transfer processing unit 2A, a second imaging unit 7B for the second transfer processing unit 2B, a determination unit 8a, and a notification unit 9. The determination unit 8a is capable of communicating with the notification unit 9, the (first) imaging unit 7A, and the second imaging unit 7B. The substrate movement system 1 also has a third imaging unit 7C for the third transfer processing unit 2C, a fourth imaging unit 7D for the fourth transfer processing unit 2D, a fifth imaging unit 7E for the fifth transfer processing unit 2E, and a sixth imaging unit 7F for the sixth transfer processing unit 2F.

[0018] As shown in FIG. 2, when the moving unit 3A moves a substrate 11A such as a wafer (e.g., a silicon wafer) relative to a system component 6A, if there is no vertical clearance C between the main surface of the substrate 11A (in this embodiment, the upper surface of the disk-shaped substrate 11A) and the system component 6A, the main surface of the substrate 11A will come into contact with the system component 6A, causing scratches on the main surface of the substrate 11A. Conversely, if the clearance C is too large, the opposite main surface (lower surface) of the substrate 11A will come into contact with another system component, potentially causing scratches on the opposite main surface of the substrate 11A. For this reason, the moving unit 3A is controlled by a control device (not shown) such as a computer so that an appropriate clearance C can be maintained during the movement of the substrate 11A. However, the clearance C may decrease due to an abnormality in the (first) gripper 4aA, a malfunction of the robot arm constituting the (first) moving unit 3A, or a malfunction of the control device controlling the robot arm. In this embodiment, by using imaging unit 7A to photograph substrate 11A and system component 6A from diagonally above substrate 11A rather than from directly to the side of substrate 11A, a mirror image 12 of system component 6A reflected on its mirror-like main surface can be captured together with its real image 13 in a single image 14, as shown in Fig. 3, and clearance C can be stably monitored based on the positional relationship between mirror image 12 and real image 13 in image 14. Therefore, a substrate transfer system 1 can be realized that can prevent the mirror-like main surface of substrate 11A from coming into contact with system component 6A during transport and causing scratches.

[0019] The determination unit 8a performs an abnormality determination based on the apparent clearance Ca (see FIG. 3) between the mirror image 12 and the real image 13 in the image 14 captured by the imaging unit 7A. According to the above configuration, the clearance C can be monitored more stably based on the apparent clearance Ca (the distance between the mirror image 12 and the real image 13) between the mirror image 12 and the real image 13 in the image 14. Since the apparent clearance Ca correlates with the actual clearance C as shown in FIG. 5, the clearance C can be monitored based on the apparent clearance Ca. FIG. 5 is a graph showing an example of the relationship between the apparent clearance Ca detected by image processing and the actual clearance C measured. The abnormality determination is performed, for example, by comparing the calculated value of the apparent clearance Ca with a threshold value. The determination unit 8a is configured with a processing device 8 (such as a computer) capable of image processing to detect the apparent clearance Ca.

[0020] The imaging unit 7A is configured with a camera such as a CCD (Charge Coupled Device) image sensor, etc. The image 14 captured by the imaging unit 7A may be a moving image or a still image.

[0021] The determination unit 8a may be configured to determine an abnormality based on a change between the clearance C calculated for the board 11A as a leading board approaching the system component 6A by the moving unit 3A and the clearance C calculated for the board 11A as a trailing board approaching the system component 6A by the moving unit 3A after the leading board has retracted from the system component 6A. This configuration allows monitoring of the change in the clearance C between the leading board and the trailing board, thereby preventing the board 11A approaching the system component 6A by the moving unit 3A after the trailing board has retracted from the system component 6A from contacting the system component 6A and causing damage. The abnormality determination is performed, for example, by comparing the change in the clearance C with a threshold value. Furthermore, the abnormality determination may be performed based not only on the change in the clearance C but also on the clearance C calculated for the leading board or the trailing board.

[0022] The substrate transfer system 1 includes a gripper 4aA and a pallet 4bA as system components 6A. The gripper 4aA clamps the substrate 11A between the gripper 4aA and a receiving portion 4dA of the pallet 4bA by advancing relative to the pallet 4bA, and releases the substrate 11A by retreating relative to the pallet 4bA. In addition to the gripper 4aA and pallet 4bA, the transport pallet 4A also includes multiple other grippers 4cA. While the number of other grippers 4cA provided on the transport pallet 4A is two in this embodiment, this is not limited to this. The transport pallet 4A may not include the other grippers 4cA. The gripper 4aA and the other grippers 4cA may each be formed from a fluororesin such as polytetrafluoroethylene. The receiving portion 4dA may be formed from an engineering plastic such as polyether ether ketone (PEEK).

[0023] The moving unit 3A performs a first transport (see the white arrow pointing to the right in Figure 1) to transport the substrate 11A in a forward direction toward the system component 6A, and a second transport (see the thick arrow pointing to the left in Figure 1) to transport the substrate 11A in a backward direction away from the system component 6A.

[0024] The moving unit 3A is composed of a robot arm having a placement unit 3aA on which the substrate 11A is placed. The substrate 11A placed on the placement unit 3aA is placed on a pallet 4bA of a transport pallet 4A by a first transport by the moving unit 3A, and is clamped between the gripper 4aA and the pallet 4bA. In this state, the substrate 11A is transported into the processing unit 5A by the transport pallet 4A, and after the specified processing, the substrate 11A is returned to its original position by the transport pallet 4A (see the double-headed thick arrow in Figure 1). Furthermore, the substrate 11A is released by the retreating gripper 4aA, and is transported from the transport pallet 4A by a second transport by the moving unit 3A.

[0025] The imaging unit 7A may be configured to constantly take images to monitor the clearance C, or may be configured to take images only when necessary. In this case, for example, a sensor 15 that detects the first conveyance may be provided, and the processing device 8 that controls the imaging unit 7A may be linked to the sensor 15, so that the imaging unit 7A takes images only when the first conveyance is performed.

[0026] 4, the substrate transfer system 1 has a notification unit 9 that issues a notification when it is determined that an abnormality has occurred through an abnormality determination. According to the above configuration, the notification can notify the system administrator 10 of the abnormality, allowing the administrator to take measures such as urging caution or inspecting or halting operation of the substrate transfer system 1. The notification unit 9 can be configured with a monitor 9a that issues a notification by displaying information on a screen, a warning light 9b that issues a notification by light, or a buzzer (not shown) that issues a notification by sound, but is not limited to these.

[0027] 4, the substrate transfer system 1 includes a second system component 6B constituting a part of the substrate transfer system 1, a second moving unit 3B that moves a second substrate 11B relative to the second system component 6B, and a second imaging unit 7B that captures a mirror image 12 of the second system component 6B and a real image 13 of the second system component 6B reflected on the mirror-like main surface of the second substrate as it is moved by the second moving unit 3B. The determination unit 8a performs a second abnormality determination to determine whether or not there is an abnormality in the clearance C between the main surface of the second substrate and the second system component 6B based on the mirror image 12 and the real image 13 captured by the second imaging unit 7B, and the notification unit 9 issues a notification when it is determined that there is an abnormality. With the above configuration, the first abnormality determination and its notification and the second abnormality determination and its notification can be performed using the common determination unit 8a and notification unit 9, thereby realizing efficient operation of the entire system. The substrate moving system 1 is not limited to the above configuration using a common judgment unit 8a, but may also be configured to have, for example, a first judgment unit (not shown) that performs a first abnormality judgment and a second judgment unit (not shown) that performs a second abnormality judgment separately provided.

[0028] Although the embodiments of the present invention have been described above, the present invention is not limited to the above-described embodiments, and the above-described embodiments can be modified in various ways without departing from the gist of the present invention. [Explanation of symbols]

[0029] 1. Substrate Transfer System 2A (1st) Transport Processing Section 2B Second transport processing section 2C 3rd transport processing section 2D 4th transport processing section 2E 5th transport processing section 2F 6th Transport Processing Section 3A (1st) Moving part 3aA Placement section 3B 2nd moving part 4A (1st) Transport Pallet 4aA (1st) Gripper 4bA (1st) Palette 4cA Other grippers 4dA Receiving part 4B Second transport pallet 4aB Second gripper 4bB 2nd Palette 5A (first) processing section 5B Second Processing Section 6A (1st) System Components 6B Second system component 7A (first) imaging unit 7B Second imaging unit 7C Third imaging unit 7D 4th imaging unit 7E 5th imaging unit 7F 6th Imaging Section 8 Processing equipment 8a Judgment section 9. Information Department 9a Monitor 9b Warning light 10 System Administrator 11A (1st) board 11B 2nd board 11C 3rd board 11D 4th board 11E 5th board 11F 6th board 12 Mirror image 13 Real Image 14 images 15 sensors C Clearance Ca apparent clearance

Claims

1. System components; a moving unit that moves the substrate relative to the system components; an imaging unit that captures a mirror image of the system component reflected on the mirror-like main surface of the substrate when the substrate is moved by the moving unit and a real image of the system component; A substrate movement system having a determination unit that performs an abnormality determination to determine whether or not there is an abnormality in the clearance between the main surface of the substrate and the system component based on the mirror image and the real image captured by the imaging unit.

2. The substrate transfer system according to claim 1 , wherein the determination unit makes the abnormality determination based on an apparent clearance between the mirror image and the real image in the image captured by the imaging unit.

3. 2. The substrate movement system of claim 1, wherein the determination unit performs the abnormality determination based on a change between the clearance calculated for the substrate as a leading substrate approaching the system component by the moving unit and the clearance calculated for the substrate as a trailing substrate approaching the system component by the moving unit after the leading substrate has retracted from the system component.

4. The substrate transfer system according to claim 1 , further comprising a notification unit that issues a notification when it is determined that an abnormality exists by the abnormality determination.

5. a second system component; and a second mover that moves a second substrate relative to the second system component; a second imaging unit that captures a mirror image of the second system component reflected on a mirror-like main surface of the second substrate when the second substrate is moved by the second moving unit and a real image of the second system component; the determination unit performs a second abnormality determination to determine whether or not there is an abnormality in a clearance between the main surface of the second board and the second system component based on the mirror image and the real image captured by the second imaging unit; The substrate transfer system according to claim 4 , wherein the notification unit issues a notification when it is determined that an abnormality exists by the second abnormality determination.

Images