Centering mechanism
By setting up a synchronous drive centering device around the wafer, the existing wafer centering cost is solved and the problem of high centering costs and inaccurate positioning is achieved, and the low-cost and high-precision wafer centering effect is achieved.
Patent Information
- Application Number
- CN202422483485.6
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2024-10-15
- Publication Date
- 2025-08-12
- Estimated Expiration
- 2034-10-15
AI Technical Summary
The existing wafer centering device is expensive and occupies space above the wafer position, resulting in inaccurate positioning and eccentricity problems.
At least three sets of centering devices are arranged around the positioning base in a space-circling manner, and the synchronous driving device is used to move it toward or away from the center of the positioning base at the same time. The precise centering of the wafer is achieved by using the limiting members and guide members to avoid occupying the space above the wafer.
Low-cost and high-precision wafer centering is achieved, which improves positioning stability and accuracy, and reduces centering costs.
Smart Images
Figure CN223218284U_ABST
Abstract
Description
Technical Field
[0001] The present application relates to the field of wafer processing technology, and in particular to a centering mechanism. Background Art
[0002] A wafer is the substrate used to manufacture semiconductor transistors or integrated circuits. Wafer centering involves adjusting the center of the wafer to a specific position through a specific method to meet the precision requirements for post-processing.
[0003] During the manufacturing process, wafers need to be frequently transferred between different carriers and wafer boxes. Since the position of the wafers may be offset by millimeters when the robot takes and places the wafers from the slots of the wafer box, moving the wafers to the carrier will cause problems such as inaccurate wafer positioning and eccentricity.
[0004] Existing centering devices usually place the wafer on a movable vacuum chuck and rotate the wafer while using optical instruments to locate the center of the wafer. However, existing optical instruments occupy the space above the wafer during the wafer centering process, and optical instruments are expensive, resulting in high centering costs. Summary of the Invention
[0005] The purpose of this application is to provide a centering mechanism, aiming to solve the defect of high wafer centering cost in related technologies.
[0006] Additional aspects and advantages of the present application will be set forth in part in the description which follows and, in part, will be obvious from the description, or may be learned by practice of the present application.
[0007] According to the first aspect of the present application, a centering mechanism is provided, comprising: a positioning base for placing a wafer; at least three groups of centering devices, which are arranged around the positioning base in an interval and surrounding manner, and each group of the centering devices is at an equal distance from the center of the positioning base; a synchronous driving device, which is configured to drive the at least three groups of centering devices to move the same distance toward or away from the center of the positioning base at the same time. When driving the at least three groups of centering devices to move the same distance toward the center of the positioning base at the same time, the centering device pushes the wafer so that the center of the wafer and the center of the positioning base are located on the same axis.
[0008] In an exemplary embodiment of the present application, radial channels corresponding to the at least three groups of centering devices are opened on the side wall of the positioning base, and the radial channels are directed toward the center of the positioning base; the centering device includes: a limit member having a limit surface directed toward the center of the positioning base for pushing the wafer; a guide member movably installed in the radial channel, an end of the guide member away from the center of the positioning base extends out of the positioning base, and the limit member is installed on this end; the end of the guide member close to the positioning base is configured to be driven by the synchronous drive device so that the guide member can slide back and forth in the radial channel.
[0009] In an exemplary embodiment of the present application, the radial channel is a radial hole; the guide member is a guide rod inserted into the radial hole; the centering device also includes a spring and a spring baffle, the spring is sleeved on the guide rod, the spring baffle is fixed at the opening of the radial hole on the side away from the center of the positioning base, the end of the spring close to the center of the positioning base is connected to the guide rod, and the end of the spring away from the positioning base abuts against the spring baffle; the end of the guide rod away from the center of the positioning base passes through the spring baffle and extends out of the positioning base.
[0010] In an exemplary embodiment of the present application, the synchronous drive device includes a cam and a rotation drive device, the rotation drive device is used to drive the cam to rotate; the center of the cam is coaxial with the center of the positioning base, and the edge of the cam is provided with at least three protrusions corresponding to at least three guide rods, and at least three grooves are formed between the at least three protrusions; when the cam rotates, the protrusion is used to push the guide rod to overcome the elastic force of the spring and move in a direction away from the center of the positioning base, and the groove is used for the guide rod to move toward the center of the positioning base under the action of the release of the elastic force of the spring.
[0011] In an exemplary embodiment of the present application, the centering device further includes a follower mounted on one end of the guide rod close to the center of the positioning base, the follower abuts against the edge of the cam, and the cam drives the guide rod to move through the follower.
[0012] In an exemplary embodiment of the present application, the follower includes: a connecting rod, one end of which is fixedly connected to the guide rod, and the extension direction of the connecting rod is parallel to the axis of the cam; a guide wheel, which is installed at the other end of the connecting rod, and the edge of the guide wheel abuts against the edge of the cam.
[0013] In an exemplary embodiment of the present application, the connecting rod is rotatably connected to the center of the guide wheel.
[0014] In an exemplary embodiment of the present application, the limiting member can be moved and fixed on the guide rod.
[0015] In an exemplary embodiment of the present application, a rotation drive device is further included for driving the cam to rotate, and the rotation drive device further includes: a gear, which coincides with the axis of the cam and is fixedly connected to the cam; a rack, which meshes with the gear; and a driving member, which is used to drive the rack to move linearly in a horizontal direction.
[0016] In an exemplary embodiment of the present application, a base plate is further included, a bracket is fixedly provided on the upper surface of the base plate, the driving member is fixed to the bracket, a guide rail base is fixedly provided on the upper surface of the base plate, a linear guide rail is fixedly provided on the side of the guide rail base facing the rack along the moving direction of the rack, and the side of the rack facing away from the gear is slidably connected to the linear guide rail.
[0017] The exemplary embodiments of the present application may have some or all of the following beneficial effects:
[0018] In a centering mechanism provided in an exemplary embodiment of the present application, a synchronous driving device is first used to drive a centering device away from the center of a positioning base to facilitate placement of a wafer on the wafer base. The synchronous driving device then drives multiple centering devices to move the same distance toward the center of the positioning base at the same time. This allows the crystal to be subjected to equal forces in multiple directions, thereby moving the wafer until its own center and the center of the positioning base are on the same axis, thereby centering the wafer. This mechanism has a relatively simple structure and low manufacturing cost, does not require space above the wafer, and reduces the cost of wafer centering.
[0019] In a centering mechanism provided in an exemplary embodiment of the present application, a cam is rotated. When the raised portion of the cam abuts against a guide wheel in a follower, a connecting rod in the follower drives a limiting member away from the center of a positioning base, thereby facilitating a worker to place a wafer on the positioning base.
[0020] In a centering mechanism provided in an example embodiment of the present application, the cam is rotated again so that the groove portion of the cam abuts against the guide wheel in the follower, and the spring releases the elastic force, driving the limit member to move toward the center direction of the positioning base to center the wafer. Through this structure, multiple limit members can be moved simultaneously to achieve the effect of centering the wafer. BRIEF DESCRIPTION OF THE DRAWINGS
[0021] The accompanying drawings are incorporated into and constitute a part of the specification, illustrate embodiments consistent with the present application, and together with the specification, are used to explain the principles of the present application. Obviously, the drawings described below are only some embodiments of the present application, and those skilled in the art can derive other drawings based on these drawings without inventive effort.
[0022] Figure 1 A schematic diagram of a centering mechanism in an embodiment of the present application is shown;
[0023] Figure 2 A top view of the centering mechanism in the wafer centering state in an embodiment of the present application is shown;
[0024] Figure 3 A cross-sectional view of the centering mechanism along the AA direction in an embodiment of the present application is shown;
[0025] Figure 4 A cross-sectional view of the centering mechanism along the BB direction in an embodiment of the present application is shown.
[0026] Description of reference numerals:
[0027] 1. Positioning base; 2. Centering device; 21. Limiting member; 22. Guide rod; 221. Step portion; 23. Spring; 24. Spring baffle; 25. Follower; 251. Connecting rod; 252. Guide wheel; 3. Synchronous drive device; 31. Cam; 311. Protrusion; 312. Groove portion; 32. Rotary drive device; 321. Gear; 322. Rack; 323. Drive member; 4. Base plate; 41. Bracket; 42. Guide rail base; 421. Linear guide. DETAILED DESCRIPTION
[0028] like Figure 1 and Figure 2 As shown, as an exemplary embodiment of the present application, a centering mechanism includes:
[0029] Positioning base 1, used for placing wafers;
[0030] At least three sets of centering devices 2 are arranged around the positioning base 1 in an interval and surrounding manner, and each set of centering devices 2 is equidistant from the center of the positioning base 1;
[0031] The synchronous driving device 3 is configured to drive at least three groups of centering devices 2 to move the same distance toward or away from the center of the positioning base 1 at the same time. When driving at least three groups of centering devices 2 to move the same distance toward the center of the positioning base 1 at the same time, the centering device 2 pushes the wafer so that the center of the wafer and the center of the positioning base 1 are on the same axis.
[0032] In the embodiment of the present application, the synchronous drive device 3 first drives the centering device 2 away from the center of the positioning base 1, then places the wafer on the positioning base 1, and then drives the centering device 2 toward the center of the positioning base 1 through the synchronous drive device 3. When the center of the wafer and the center of the positioning base 1 are on the same axis, the limiter 21 no longer applies force to the wafer. The adjacent centering devices 2 are spaced equally apart. This ensures that during the wafer positioning process, force is applied to the wafer only when needed, improving the stability and accuracy of wafer positioning and reducing damage to the wafer.
[0033] In the present application, the number of centering devices 2 can be set to three, four, five, six or even more groups. Increasing the number of centering devices 2 can improve the effect of wafer centering and make wafer centering more accurate. At the same time, each group of positioning devices is at an equal distance from the center of the positioning base 1, which ensures that the positioning of the wafer in all directions is uniform, thereby improving the accuracy and stability of wafer positioning. In the embodiment of the present application, the centering devices 2 are preferably set to six groups.
[0034] In the embodiment of the present application, each set of centering devices 2 includes a limiting member 21 , and the limiting member 21 has a limiting surface on a side facing the positioning base 1 for pushing the wafer to move.
[0035] Furthermore, in order to improve the stability of the limiting member 21 during movement, a plurality of radial channels are provided on the sidewall of the positioning base 1, which are oriented toward the center of the positioning base 1. The radial channels correspond one-to-one with the centering device 2. The radial channels are preferably holes, but are not particularly limited thereto and may also be grooves or guide rails provided at the bottom of the positioning base 1. The centering device 2 also includes a guide member, which is capable of moving within the radial channel. The end of the guide member, which is away from the center of the positioning base 1, extends out of the positioning base 1 and is fixedly mounted to the limiting member 21. The end of the guide member, which is closer to the positioning base 1, is configured to be driven by a synchronous drive device 3 so that the guide member can slide back and forth within the radial channel.
[0036] In one embodiment of the present application, the synchronization device includes a drive disk and an articulated rod. Multiple articulated rods are provided, each corresponding to a plurality of stoppers 21. The ends of the articulated rods are respectively hinged to the sidewalls of the drive disk and the stoppers 21. By rotating the drive disk clockwise and counterclockwise, the stoppers 21 can be moved toward or away from the center of the positioning base 1 under the guidance of the guide members and radial channels.
[0037] like Figure 4 As shown, in another implementation of the embodiment of the present application, the radial channel is a radial hole, and the guide member is a guide rod 22 passing through the radial hole.
[0038] The centering device 2 also includes a spring 23 and a spring retainer 24. The spring 23 is positioned within the radial hole and is mounted on the guide rod 22. The spring retainer 24 is fixed to the opening of the radial hole away from the center of the positioning base 1. The end of the spring 23 near the center of the positioning base 1 is connected to the guide rod 22, while the end of the spring 23 away from the center of the positioning base 1 abuts the spring retainer 24. The method of connection between the spring 23 and the guide rod 22 is not particularly limited and can be welded or glued. As a preferred embodiment of the present application, the end of the guide rod 22 located within the radial hole is provided with a stepped portion 221, and the end of the spring 23 near the center of the positioning base 1 abuts the stepped portion 221. The spring retainer 24 is fixedly connected to the side wall of the positioning base 1. The connection method is not restrictive and can be bolted, welded, glued, or otherwise secured. This design allows the spring 23 to be stably stored within the radial hole. When the spring 23 releases its elastic potential energy, it can drive the guide rod 22 and the stopper 21 to move toward the center of the positioning base 1.
[0039] Furthermore, one end of the guide rod 22 away from the stepped portion 221 passes through the spring baffle 24 and is connected to the base limiter 21 on the outside of the radial hole. The connection method between the guide rod 22 and the limiter 21 is not particularly limited, and can be welding, clamping, pasting, interference fit, etc. The connection method between the guide rod 22 and the limiter 21 is preferably such that the limiter 21 can be moved and fixed on the guide rod 22, such as a threaded connection. Through this connection method, the position of the limiter 21 on the guide rod 22 can be adjusted to ensure that after the wafer size changes, the limiter 21 can still meet the requirement of not applying force to the wafer when it abuts against the side wall of the wafer.
[0040] In the embodiment of the present application, the synchronous drive device 3 includes a cam 31, which is located below the positioning base 1. The rotation axis of the cam 31 is coaxial with the center of the positioning base 1. The cam 31 is rotatably connected to the positioning base 1. The axial sidewall of the cam 31 is provided with a plurality of protrusions 311, and grooves 312 are formed between adjacent protrusions 311. The number and position of the protrusions 311 and the grooves 312 match those of the centering device 2. Therefore, in the present application, six protrusions 311 are provided, and adjacent protrusions 311 are equally spaced. This design makes the rotation of the cam 31 more stable and uniform, and improves the accuracy and effect of centering.
[0041] Furthermore, in order to enable the rotation of the cam 31 to drive the movement of the stopper 21, the centering device 2 also includes a follower 25. One end of the follower 25 is connected to the end of the guide rod 22 near the center of the positioning base 1, and the other end of the follower 25 abuts the edge of the cam 31. Thus, when the cam 31 rotates, when the protrusion 311 of the cam 31 abuts the follower 25, the follower 25 drives the guide rod 22 and the stopper 21 away from the center of the positioning base 1, at which time the spring 23 is in a compressed state; when the groove 312 of the cam 31 abuts the follower 25, the spring 23 releases its elastic force, driving the guide rod 22, the follower 25, and the stopper 21 to move toward the center of the positioning base 1.
[0042] In the embodiment of the present application, the follower 25 includes a guide wheel 252 and a connecting rod 251. A movable groove is formed on the lower surface of the positioning base 1, which is connected to the radial hole. The connecting rod 251 passes through the movable groove in a vertical direction and can move horizontally within the movable groove. One end of the connecting rod 251 is fixedly connected to the end of the guide rod 22 located in the radial hole. The fixing method is not restrictive and can be threaded, plugged, welded, or glued. The other end of the connecting rod 251 is connected to the center of the guide wheel 252. The axis of the guide wheel 252 is parallel to the axis of the cam 31. The connection structure between the connecting shaft and the guide wheel 252 is not restrictive and can be fixed or rotatable. A rotatable connection is preferably used to reduce friction between the cam 31 and the follower 25 and improve stability. The guide wheel 252 abuts the cam 31. This design allows the cam 31 to rotate and drive the guide wheel 252 to move away from the center of the positioning base 1.
[0043] With the above structure, when a wafer needs to be placed, the cam 31 is rotated so that each protrusion 311 of the cam 31 abuts each guide wheel 252, causing the guide wheels 252 to rotate and move linearly away from the center of the positioning base 1. This linear motion causes the guide wheels 252 to move the guide rods 22 via the connecting rods 251, and the guide rods 22 in turn move the stoppers 21, moving each stopper 21 away from the center of the positioning base 1. This increases the area between the stoppers 21, making it easier for workers to place wafers on the positioning base 1.
[0044] When the limiter 21 is away from the positioning base 1, the elastic member is in a compressed state. As the raised portion 311 of the cam 31 gradually moves away from the guide wheel 252, the elastic member releases its elastic force, driving the guide rod 22, the limiter 21 and the follower 25 to move toward the center of the positioning base 1, and the guide wheel 252 abuts against the groove portion 312 of the cam 31. This multi-directional retraction process causes multiple limiters 21 to simultaneously retract toward the center of the positioning base 1, ultimately causing the center of the wafer and the center of the positioning base 1 to be on the same axis. This design achieves the centering effect on the wafer and improves the accuracy of subsequent wafer processing.
[0045] Furthermore, the method of rotating the cam 31 is relatively flexible. The cam 31 can be rotated manually or with the help of a device that can provide rotational power to the cam 31, such as a motor.
[0046] like Figure 4 As shown, as a preferred solution of the embodiment of the present application, the synchronous drive device 3 in the embodiment of the present application further includes a rotation drive device 32 for providing rotational power to the cam 31. The rotation drive device 32 includes:
[0047] The gear 321 coincides with the axis of the cam 31 and is fixedly connected to the lower surface of the cam 31;
[0048] The rack 322 moves in the horizontal direction and meshes with the gear 321;
[0049] The driving member 323 can drive the rack 322 to move linearly in the horizontal direction, such as a cylinder, a linear motor, a hydraulic cylinder, etc.; in the embodiment of the present application, a cylinder is preferably used as the driving member 323.
[0050] The driving member 323 drives the rack 322 to move linearly, so that the rack 322 engages with the gear 321, drives the gear 321 to rotate, and the gear 321 drives the cam 31 to rotate, thereby achieving the effect of providing rotational power to the cam 31.
[0051] Furthermore, in order to improve the stability of the connection between the gear 321 and the cam 31, and to make the gear 321 receive more uniform force when providing rotational force to the cam 31, the rotation axes of the cam 31 and the gear 321 are located on the same vertical axis, and a boss is fixedly provided on the lower surface of the cam 31. The center of the gear 321 is a hollow structure, and the boss is located at the center of the gear 321 and is fixedly connected to the circumferential inner wall of the gear 321.
[0052] The centering mechanism in the embodiment of the present application further includes a base plate 4. A bracket 41 is fixedly mounted on the upper surface of the base plate 4. The driver 323 is mounted and fixed to the bracket 41. The bracket 41 is used to provide good stability for the driver 323. A guide rail base 42 is fixedly mounted on the upper surface of the base plate 4 in a vertical direction. A linear guide rail 421 is fixedly mounted on the side of the guide rail base 42 facing the rack 322 along the direction of movement of the rack 322. The side of the rack 322 facing away from the gear 321 is slidably connected to the linear guide rail 421.
[0053] Those skilled in the art will readily appreciate other embodiments of the present invention after considering the specification and practicing the embodiments of the present invention. This application is intended to cover any variations, uses, or adaptations of the present invention that follow the general principles of the present invention and include common knowledge or customary techniques in the art that are not covered by this application. The specification and embodiments are intended to be exemplary only, and the true scope and spirit of the present invention are indicated by the appended claims.
Claims
1. A centering mechanism, characterized in that: include: A positioning base (1) for placing a wafer; At least three groups of centering devices (2) are arranged around the positioning base (1) in an interval and surrounding manner, and each group of the centering devices (2) is equidistant from the center of the positioning base (1); The synchronous driving device (3) is configured to drive the at least three sets of centering devices (2) to move the same distance simultaneously in a direction close to or away from the center of the positioning base (1); when driving the at least three sets of centering devices (2) to move the same distance simultaneously in a direction close to the center of the positioning base (1), the centering device (2) pushes the wafer so that the center of the wafer and the center of the positioning base (1) are located on the same axis.
2. A centering mechanism according to claim 1, characterized in that: The side wall of the positioning base (1) is provided with radial channels corresponding to the at least three sets of centering devices (2), and the radial channels face the center of the positioning base (1); The centering device (2) comprises: A limiting member (21) having a limiting surface facing the center of the positioning base (1) for pushing the wafer; A guide member is movably mounted in the radial channel, wherein one end of the guide member away from the center of the positioning base (1) extends out of the positioning base (1), and the limit member (21) is mounted on the end; and one end of the guide member close to the positioning base (1) is configured to be driven by the synchronous drive device (3) so that the guide member can slide back and forth in the radial channel.
3. A centering mechanism according to claim 2, characterized in that: The radial channel is a radial hole; the guide member is a guide rod (22) inserted into the radial hole; The centering device (2) further comprises a spring (23) and a spring baffle (24), wherein the spring (23) is sleeved on the guide rod (22), and the spring baffle (24) is fixed at an opening of the radial hole on a side away from the center of the positioning base (1), and one end of the spring (23) close to the center of the positioning base (1) is connected to the guide rod (22), and one end of the spring (23) away from the positioning base (1) abuts against the spring baffle (24); One end of the guide rod (22) away from the center of the positioning base (1) passes through the spring baffle (24) and extends out of the positioning base (1).
4. A centering mechanism according to claim 3, characterized in that: The synchronous driving device (3) comprises a cam (31) and a rotation driving device (32), wherein the rotation driving device (32) is used to drive the cam (31) to rotate; the center of the cam (31) is coaxial with the center of the positioning base (1); the edge of the cam (31) is provided with at least three protrusions (311) corresponding to at least three guide rods (22); at least three grooves (312) are formed between the at least three protrusions (311); when the cam (31) rotates, the protrusions (311) are used to push the guide rod (22) to overcome the elastic force of the spring (23) and move in a direction away from the center of the positioning base (1); the grooves (312) are used to enable the guide rod (22) to move in a direction close to the center of the positioning base (1) under the action of the release of the elastic force of the spring (23).
5. A centering mechanism according to claim 4, characterized in that: The centering device (2) further comprises a follower (25) mounted on one end of the guide rod (22) close to the center of the positioning base (1); the follower (25) abuts against the edge of the cam (31); and the cam (31) drives the guide rod (22) to move via the follower (25).
6. A centering mechanism according to claim 5, characterized in that: The follower (25) comprises: A connecting rod (251), one end of which is fixedly connected to the guide rod (22), and an extending direction of the connecting rod (251) is parallel to the axis of the cam (31); The guide wheel (252) is mounted on the other end of the connecting rod (251), and the edge of the guide wheel (252) abuts against the edge of the cam (31).
7. A centering mechanism according to claim 6, characterized in that: The connecting rod (251) is rotatably connected to the center of the guide wheel (252).
8. A centering mechanism according to claim 3, characterized in that: The limiting member (21) can be moved and fixed on the guide rod (22).
9. A centering mechanism according to claim 4, characterized in that: It also includes a rotation drive device (32) for driving the cam (31) to rotate, and the rotation drive device (32) further includes: a gear (321) coinciding with the axis of the cam (31) and fixedly connected to the cam (31); a rack (322) meshing with the gear (321); The driving member (323) is used to drive the rack (322) to move linearly in the horizontal direction.
10. A centering mechanism according to claim 9, characterized in that: The invention also includes a base plate (4), wherein a bracket (41) is fixedly provided on the upper surface of the base plate (4), the driving member (323) is fixedly mounted on the bracket (41), a guide rail base (42) is fixedly provided on the upper surface of the base plate (4), a linear guide rail (421) is fixedly provided on the guide rail base (42) along the moving direction of the rack (322) on the side facing the rack (322), and the side of the rack (322) facing away from the gear (321) is slidably connected to the linear guide rail (421).