Wafer position deviation prevention device and wafer processing system

Abstract

The utility model provides a wafer position deviation prevention device and a wafer processing system, the wafer position deviation prevention device comprises a driving structure, a first detection part and a controller, the driving structure comprises a driving part and a push rod, the push rod is provided with a first end and a second end, and the driving part is used for driving the first end of the push rod to rotate so that the second end of the push rod is folded towards a wafer; the controller is electrically connected with the driving part and the first detection part, the first detection part is used for detecting the position of the wafer, and the controller is used for controlling the driving part to drive the push rod to rotate by a preset angle when the first detection part detects that the position of the wafer deviates. According to the device for preventing the position deviation of the wafer, the problems of machine alarm caused by deviation of the wafer on the bearing seat and etching of defective products caused by position deviation of the wafer are prevented, and the yield of the wafer is improved.

Description

Technical Field

[0001] The utility model belongs to the technical field of semiconductor processing, and more specifically, relates to a device for preventing wafer position deviation and a wafer processing system. Background Art

[0002] During the semiconductor etching process, wafers are transported from a wafer pod to a vacuum chamber by a robotic arm. During this transfer process, the wafer is transferred to the electrostatic chuck (ESC) within the vacuum chamber for etching. The alignment of the wafer center with the ESC center significantly impacts post-etch uniformity, critical dimensions, and topography.

[0003] If the wafer position shifts due to the offset of the LM's transfer arm when the wafer loading module (Load Module; LM)'s transfer arm transfers the wafer to the wafer binding module (Load lock Module; LLM) during the wafer transfer process, and the transfer arm of the transfer module (Transfer Module; TM) then transfers the wafer to the vacuum chamber, a large offset will occur when the wafer is placed. When the offset occurs during the transfer process and the wafer is transferred to the ESC, the equipment does not calibrate the wafer position in time, and defective products will be obtained after etching. When the wafer is transferred out of the vacuum chamber after processing, the robotic arm relies on friction to grab the wafer and stop it on the wafer support. There is also a chance of wafer position shift, which will cause a machine alarm. The machine alarm needs to be handled manually. However, manually adjusting the wafer position will destroy the microenvironment, causing potential contamination particles to fall on the wafer, affecting the wafer yield. Utility Model Content

[0004] The purpose of the utility model is to provide a device for preventing wafer position deviation and a wafer processing system, so as to solve the problem that during wafer processing, the position of the wafer is deviated while the robotic arm is transferring the wafer, causing the machine to alarm or affecting the wafer yield.

[0005] To achieve the above-mentioned purpose, the technical solution adopted by the present invention is as follows: In a first aspect, the present invention provides a device for preventing wafer position deviation, comprising:

[0006] A driving structure, a first detection unit and a controller;

[0007] There are multiple driving structures, which are arranged at circumferential intervals below the wafer support. The driving structure includes a driving part and a push rod connected to the driving part. The push rod has a first end and a second end. The driving part is used to drive the first end to rotate so that the second end is retracted toward the wafer. The controller is electrically connected to the driving part and the first detection part respectively. The first detection part is used to detect the position of the wafer. The controller is used to control the driving part to drive the first end of the push rod to rotate by a preset angle when the first detection part detects that the wafer position is offset.

[0008] In one embodiment, a side of the push rod facing the wafer supporting seat is provided with an arc-shaped surface for fitting with an edge of the wafer.

[0009] In one embodiment, the driving structure is disposed on a track arranged along the radial direction of the wafer supporting seat, and the position of the driving structure on the track is adjustable.

[0010] In one embodiment, the first detection unit includes a signal transmitting unit and a signal receiving unit, the number of the first detection units is at least three, and the first detection units are evenly spaced.

[0011] In one embodiment, the number of the driving structures is four. After the push rods rotate by a preset angle, the outer contour of the line connecting the second ends of the four push rods is a rectangle, and the distance between the second ends of two push rods located on the diagonal line of the rectangle is the diameter of the wafer.

[0012] In one embodiment, the distance between the first end of the push rod and the center of the wafer supporting seat is the radius of the wafer, and the preset angle is 90 degrees.

[0013] In one embodiment, a second detection portion is provided at the second end of the push rod, and the second detection portion is electrically connected to the controller. The second detection portion is used to detect the distance between the second ends of the two push rods located on the diagonal of the rectangle, and the controller is used to control the driving portion to drive the first end of the push rod to rotate when the distance does not reach a preset distance.

[0014] In one embodiment, the driving unit is a stepping motor.

[0015] In one embodiment, the push rod is made of polytetrafluoroethylene.

[0016] A second aspect of the present invention provides a wafer processing system, comprising: the device for preventing wafer position deviation as described above.

[0017] The present invention provides a device for preventing wafer position deviation, comprising a driving structure, a first detection unit, and a controller. The driving structures are arranged circumferentially at intervals below a wafer support seat. The driving structure comprises a driving unit and a push rod, the push rod having a first end and a second end. The driving unit is configured to drive the first end of the push rod to rotate so that the second end of the push rod is retracted toward the wafer. The controller is electrically connected to the driving unit and the first detection unit, respectively. The first detection unit is configured to detect the position of the wafer. The controller is configured to control the driving unit to drive the first end of the push rod to rotate by a preset angle when the first detection unit detects a wafer position deviation. The driving structures of the device for preventing wafer position deviation are arranged circumferentially at intervals below the wafer support seat. When the first detection unit detects a wafer position deviation, the controller controls the driving unit to drive the push rod to rotate by a preset angle so that the second end of the push rod is aligned with the wafer, thereby positioning the wafer directly above the wafer support seat. This avoids or reduces the problem of machine alarms caused by wafer deviation on the support seat and the problem of etching defective products caused by wafer position deviation, thereby improving the yield rate during the wafer etching process. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] In order to more clearly illustrate the technical solutions in the embodiments of the present invention, the following briefly introduces the drawings required for use in the embodiments or the description of the prior art. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative work.

[0019] Figure 1 A schematic structural diagram of a device for preventing wafer position deviation provided by an embodiment of the present utility model;

[0020] Figure 2 A schematic diagram of the structure after wafer offset and position calibration provided by an embodiment of the present utility model;

[0021] Figure 3 This is a top view of the wafer position after the wafer position is calibrated by the device for preventing wafer position deviation provided by an embodiment of the present invention.

[0022] Among them, the reference numerals in the figures are:

[0023] 1-driving structure; 2-first detection part; 3-wafer supporting seat; 4-wafer; 5-second detection part; 11-push rod; 111-arc surface. DETAILED DESCRIPTION

[0024] To make the purpose, technical solutions, and advantages of the embodiments of the present invention more clear, the technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the embodiments described are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative efforts shall fall within the scope of protection of the present invention.

[0025] In the description of the present invention, it should be understood that the terms "including" and "having" and any variations thereof used herein are intended to cover non-exclusive inclusions. For example, a process, method, system, product or apparatus comprising a series of steps or units is not necessarily limited to those steps or units explicitly listed, but may include other steps or units not explicitly listed or inherent to these processes, methods, products or apparatuses.

[0026] It should be understood that the terms "length", "width", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", etc., indicating the orientation or position relationship, are based on the orientation or position relationship shown in the accompanying drawings, and are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on the present invention.

[0027] Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of the technical features being referred to. Thus, a feature specified as "first" or "second" may explicitly or implicitly include one or more of such features. In the description of this utility model, unless otherwise specified, "plurality" means two or more.

[0028] During the semiconductor etching process, the wafer is grabbed by a robotic arm and transferred from the wafer transfer box to the reaction chamber for processing. If the LM's transfer arm transfers the wafer to the wafer binding module LLM during the wafer transfer process, the wafer position drifts due to the offset of the LM's transfer arm. Then the TM's transfer arm transfers the wafer to the vacuum chamber, and a large offset occurs when the wafer is placed. When an offset occurs during the transfer process and the wafer is transferred to the ESC, the equipment does not calibrate the wafer position in time, and defective products will be obtained after etching. After the wafer is processed and transferred from the reaction chamber, the robotic arm relies on friction to grab the wafer and stop it on the wafer stage. There is also a chance of wafer position offset, which will cause a machine alarm. The machine alarm needs to be handled manually. However, manually adjusting the wafer position will destroy the microenvironment, causing potential particles to fall on the wafer, affecting the wafer yield. Based on this, the present application proposes a device for preventing wafer position offset and a wafer processing system.

[0029] The device for preventing wafer position deviation and the wafer processing system provided by the present application are described in detail below with reference to specific embodiments.

[0030] Figure 1 This is a schematic diagram of the structure of the device for preventing wafer position deviation provided by an embodiment of the present invention. Figure 2 This is a schematic diagram of the structure after wafer offset and position calibration provided by an embodiment of the present invention. Figure 3 This is a top view of the wafer position after the wafer position is calibrated by the device for preventing wafer position deviation provided by the embodiment of the present invention. Figure 1-3 A first aspect of this embodiment provides a device for preventing wafer position deviation, including a driving structure 1, a first detection unit 2 and a controller.

[0031] There are multiple drive structures 1, which are used to be arranged at circumferential intervals below the wafer support 3. The drive structure 1 includes a drive part 12 and a push rod 11 connected to the drive part 12. The push rod 11 has a first end and a second end. The drive part is used to drive the first end to rotate so that the second end is retracted toward the wafer 4. The controller is electrically connected to the drive part and the first detection part 2 respectively. The first detection part 2 is used to detect the position of the wafer 4. The controller is used to control the drive part to drive the first end of the push rod 11 to rotate a preset angle when the first detection part 2 detects that the position of the wafer 4 is offset.

[0032] The number of drive structures 1 in this embodiment is multiple, and the multiple drive structures 1 are arranged below the wafer support seat 3 at intervals along the circumferential direction. For example, the number of drive structures 1 in this embodiment is four, and the four drive structures 1 are evenly arranged below the wafer support seat 3 at intervals along the circumferential direction. The drive structure 1 in this embodiment includes a drive unit 12 and a push rod 11 connected to the drive end of the drive unit 12. This embodiment does not impose any special restrictions on the specific structure of the drive unit 12. For example, the drive unit 12 is a motor. The distance between the first end of the push rod 11 in this embodiment and the center of the wafer support seat 3 is equal to the radius of the wafer 4. Of course, in other embodiments, the distance between the first end of the push rod 11 and the center of the wafer support seat 3 can also be greater than or less than the radius of the wafer 4, as long as the second end of the push rod 11 is in contact with the edge of the wafer after the push rod 11 rotates to a preset angle.

[0033] The first detection unit 2 of this embodiment is used to detect the position of the wafer 4. Exemplarily, the first detection unit 2 includes a transmitter and a receiver, one of which is mounted below the wafer support 3, and the other is mounted above the wafer support 3. The transmitter and the receiver are equidistant from the center of the wafer support 3. After the wafer 4 is placed on the wafer support 3, when the wafer 4 is exactly centered on the wafer support 4 without deviation, the receiver can receive the signal from the transmitter. When the position of the wafer 4 is offset, the receiver cannot receive the signal from the transmitter.

[0034] The controller of this embodiment is electrically connected to the driving unit 12 and the first detection unit 2, respectively. When the first detection unit 2 detects that the position of the wafer 4 is offset, the controller controls the driving unit 12 to drive the push rod 11 to rotate by a preset angle. In this embodiment, the driving structure is arranged below the wafer support seat 3 along the circumferential interval. The first end of the push rod 11 is spaced equal to the center of the wafer support seat 3. The distance between the first end of the push rod 11 and the center of the wafer support seat 3 is equal to the radius of the wafer 4. The push rod 11 of this embodiment is in a horizontal state in the initial state. After rotating 90 degrees, the second end of the push rod 11 contacts the edge of the wafer 4. The distance between the second end of the push rod 11 and the center of the wafer support seat 3 is equal to the radius of the wafer 4. The wafer 4 is located at the center of the wafer support seat 3, preventing the position of the wafer 4 from offset.

[0035] The present embodiment provides a device comprising a drive structure, a first detection unit, and a controller. The drive structure is provided in a plurality of circumferentially spaced locations below a wafer support. The drive structure comprises a drive unit 12 and a push rod. The push rod has a first end and a second end. The drive unit is configured to drive the first end of the push rod to rotate so that the second end of the push rod is retracted toward the wafer. The controller is electrically connected to the drive unit and the first detection unit, respectively. The first detection unit is configured to detect the position of the wafer. The controller is configured to control the drive unit to drive the push rod to rotate a preset angle when the first detection unit detects a wafer position deviation. The drive structure of the device for preventing wafer position deviation is circumferentially spaced locations below the wafer support. When the first detection unit detects a wafer position deviation, the controller controls the drive unit to drive the push rod to rotate a preset angle until the second end of the push rod is aligned with the wafer. The distance between the second end of the push rod and the center of the wafer support is the radius of the wafer. The wafer is located directly above the wafer support, thereby avoiding or reducing the problem of machine alarms caused by wafer deviation on the support and etching defective products caused by wafer position deviation, thereby improving the yield rate of the wafer etching process.

[0036] Furthermore, the push rod 11 is provided with a curved surface 111 on the side facing the wafer support seat 3 for fitting with the edge of the wafer 4. In this embodiment, the push rod 11 is provided with a curved surface 11 on the side facing the wafer support seat 3 for fitting with the edge of the wafer 4. The side of the push rod 11 in contact with the wafer 4 adopts an arc-shaped design, which can prevent stress concentration at the wafer notch point during calibration, causing the wafer 4 to break.

[0037] Furthermore, the drive structure 1 is disposed on a track arranged along the radial direction of the wafer support 3. By placing the drive structure 1 on the track arranged along the radial direction of the wafer support 3, the device for preventing wafer position shifting of this embodiment can be used even when wafers 4 of different diameters are placed on the wafer support 3. For example, when placing wafers of different diameters on the wafer support 3 of this embodiment, the drive structure 1 only needs to be moved on the track so that the distance between the first end of the push rod 11 and the center of the wafer support 3 is equal to the radius of the wafer 4 to be placed. The push rod 11 is initially horizontal. After the push rod 11 rotates 90 degrees, the distance between the second end of the push rod 11 and the center of the wafer support 3 is equal to the radius of the wafer. That is, after the push rod 11 rotates 90 degrees, the wafer 4 is centered on the wafer support 3. The device for preventing wafer position shifting of this embodiment can be used to prevent shifting of wafers 4 of various sizes. For example, by changing the position of the drive structure 1, this embodiment can be applied to 12-inch wafers, 8-inch wafers, or 6-inch wafers.

[0038] In a specific embodiment, the first detection part 2 includes a signal transmitting part and a signal receiving part, the number of the first detection parts 2 is at least three, and the first detection parts 2 are evenly spaced. The first detection parts 2 of this embodiment include four, and the four first detection parts 2 are evenly spaced along the circumference of the wafer support seat 3. The signal transmitting part is arranged above the wafer support seat 3, and the signal receiving part is arranged below the wafer support seat 3. This embodiment improves the accuracy of detection by arranging multiple first detection parts 2. Among the four first detection parts 2 of this embodiment, when the signal receiving part of one of the first detection parts 2 cannot receive the signal of the signal transmitting part, it indicates that the position of the wafer 4 is offset.

[0039] In one embodiment, see Figure 1 and Figure 3 The number of the driving structures 1 is four. After the push rods 11 rotate by a preset angle, the outer contour of the line connecting the second ends of the four push rods 11 is a rectangle, and the distance between the second ends of the two push rods 11 located on the diagonal line of the rectangle is the diameter of the wafer 4.

[0040] In one embodiment, see Figure 1 , the distance between the first end of the push rod and the center of the wafer support seat is the radius of the wafer, and the preset angle is 90 degrees. In the initial state of the device for preventing wafer position deviation of this embodiment, the push rod 11 is in a horizontal state. When the first detection unit 2 detects the position deviation of the wafer 4, the driving unit 12 is controlled to drive the push rod 11 to rotate 90 degrees. After the push rod 11 rotates 90 degrees, the distance between the second end of the push rod 11 and the wafer support seat 3 is the radius of the wafer 4. In the initial state of the device for preventing wafer position deviation of this embodiment, the push rod 11 is in a horizontal state and occupies little space in the vertical direction.

[0041] In a specific embodiment, the second end of the push rod 11 is provided with a second detection portion 5, and the second detection portion 5 is electrically connected to the controller. The second detection portion 5 is used to detect the distance between the second ends of the two push rods 11 located on the diagonal of the rectangle. The controller is used to control the driving portion 12 to drive the push rod 11 to rotate when the distance does not reach a preset distance. This embodiment monitors the position of the push rod 11 after the push rod 11 rotates a preset angle by setting a second detection portion 5 at the second end of the push rod 11 to ensure that the rotation angle of the push rod 11 reaches a preset value. The number of the driving structures 1 of this embodiment is four. After the push rod 11 rotates the preset angle, the outer contour of the line connecting the second ends of the four push rods 11 is a rectangle. The distance between the second ends of the two push rods 11 located on the diagonal of the rectangle is the diameter of the wafer 4. When the second detection portion 5 detects that the distance between the second ends of the two push rods 11 located on the diagonal of the rectangle is the diameter of the wafer 4, it represents that the push rod 11 has rotated into place. At this time, the center of the wafer 4 coincides with the center of the wafer support 3. The wafer position shift prevention device of this embodiment can reduce the potential for wafer 4 to shift within the vacuum chamber due to shifting in the LLM during subsequent transfer of the wafer 4 from the TM robotic arm to the vacuum chamber, or shifting during transfer from the TM to the LLM. Monitoring by the first and second detection units 2 and 5 ensures accurate repositioning of the wafer 4, reducing the likelihood of machine downtime and the resulting etching defects caused by wafer 4 shifting, further improving yield.

[0042] In one specific embodiment, the drive unit 12 is a stepper motor. The stepper motor's rotation angle can be precisely controlled, with each step corresponding to a specific rotation angle. This motor has very high rotation accuracy, and compared to traditional DC and AC motors, it can more accurately control position and angle. In this embodiment, four stepper motors are used, and the four stepper motors can be arranged in series or in parallel in the circuit.

[0043] In the above embodiment, the push rod 11 is made of polytetrafluoroethylene, which is a material with a low friction coefficient, thereby reducing the risk of the wafer 4 being damaged.

[0044] A second aspect of this embodiment provides a wafer processing system, including the device for preventing wafer position deviation as described in the above embodiment.

[0045] For example, a device for preventing wafer position deviation includes: a driving structure, a first detection unit, and a controller;

[0046] There are multiple driving structures, which are used to be arranged at circumferential intervals below the wafer support. The driving structure includes a driving part and a push rod connected to the driving part. The push rod has a first end and a second end. The driving part is used to drive the first end to rotate so that the second end is retracted toward the wafer. The controller is electrically connected to the driving part and the first detection part respectively. The first detection part is used to detect the position of the wafer. The controller is used to control the driving part to drive the push rod to rotate a preset angle when the first detection part detects that the wafer position is offset.

[0047] The wafer processing system provided by an embodiment of the present invention includes the above-mentioned device for preventing wafer position deviation, and the driving structure of the device for preventing wafer position deviation is arranged at circumferential intervals below the wafer support seat. When the first detection part detects the wafer position deviation, the controller controls the driving part to drive the push rod to rotate a preset angle, and then the second end of the push rod fits with the wafer, so that the wafer is located directly above the wafer support seat, avoiding or reducing the machine alarm caused by the deviation of the wafer on the support seat and the problem of etching defective products caused by the position deviation of the wafer, thereby improving the yield of the wafer etching process.

[0048] The above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit it. Although the present invention has been described in detail with reference to the above embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the above embodiments, or replace some or all of the technical features therein with equivalents. However, these modifications or replacements do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of the present invention.

Claims

1. A device for preventing wafer position deviation, characterized in that: include: A driving structure, a first detection unit and a controller; There are multiple driving structures, which are arranged at circumferential intervals below the wafer support. The driving structure includes a driving part and a push rod connected to the driving part. The push rod has a first end and a second end. The driving part is used to drive the first end to rotate so that the second end is retracted toward the wafer. The controller is electrically connected to the driving part and the first detection part respectively. The first detection part is used to detect the position of the wafer. The controller is used to control the driving part to drive the first end of the push rod to rotate by a preset angle when the first detection part detects that the wafer position is offset.

2. The device for preventing wafer position deviation according to claim 1, wherein: A side of the push rod facing the wafer supporting seat is provided with an arc surface for fitting with the edge of the wafer.

3. The device for preventing wafer position deviation according to claim 1, wherein: The driving structure is arranged on a track arranged along the radial direction of the wafer supporting seat, and the position of the driving structure on the track is adjustable.

4. The device for preventing wafer position deviation according to claim 1, wherein: The first detection unit includes a signal transmitting unit and a signal receiving unit. The number of the first detection units is at least three, and the first detection units are evenly spaced.

5. The device for preventing wafer position deviation according to claim 1, wherein: There are four driving structures. After the push rods rotate a preset angle, the outer contour of the line connecting the second ends of the four push rods is a rectangle, and the distance between the second ends of two push rods located on the diagonal of the rectangle is the diameter of the wafer.

6. The device for preventing wafer position deviation according to claim 5, wherein: The distance between the first end of the push rod and the center of the wafer supporting seat is the radius of the wafer, and the preset angle is 90 degrees.

7. The device for preventing wafer position deviation according to claim 1, wherein: The driving part is a stepping motor.

8. The device for preventing wafer position deviation according to any one of claims 1 to 7, wherein: The push rod is made of polytetrafluoroethylene.

9. A wafer processing system, characterized in that: include: The device for preventing wafer position deviation according to any one of claims 1 to 8.

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