Wafer transfer mechanical wrist joint mechanism, mechanical hand and calibration method
By using the automatic station calibration and elastic buffer structure of the flexible calibration and testing components, the problems of large space occupation and long wafer unloading time of the existing wafer transfer mechanical wrist joint structure are solved, realizing low-cost and high-efficiency wafer transfer.
Patent Information
- Application Number
- CN202611516566.9
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2026-09-28
- Publication Date
- 2026-11-06
AI Technical Summary
Existing wafer transfer robotic wrist joint structures occupy large cavity space and are costly, and the time spent unloading the workpiece is long, resulting in high equipment costs and limited production capacity.
A flexible calibration and detection component is adopted, including an elastic substrate, a reset component, and a trigger component. Automatic station calibration is achieved through a microswitch, reducing the number of sensors. Combined with the reset component, an elastic buffer structure is formed, simplifying the calibration process.
It has achieved fully automated workstation calibration, reduced equipment costs, increased production line capacity, reduced wafer breakage and mechanical component wear, simplified equipment maintenance, and shortened wafer unloading time.
Smart Images
Figure CN123040133A_ABST
Abstract
Description
Technical Field
[0001] This application relates to the field of wafer transfer technology, and in particular to a wafer transfer robotic wrist joint mechanism, robotic hand, and calibration method. Background Technology
[0002] Semiconductor manufacturing equipment relies on robotic arms to pick up and place wafers between worktables and memory cells. Existing robotic arm joint structures for such equipment suffer from the following three problems: 1. The mainstream high-precision station calibration of wrist joints adopts a four-quadrant sensor calibration structure, which occupies a large amount of cavity space, has a complex structure, and has a high cost, thus increasing the equipment cost. 2. The current workpiece stage uses a docked wrist joint for unloading, which limits production capacity. Traditionally, when unloading workpieces from a workpiece stage, the robot arm needs to use docking to achieve micron-level high-precision alignment, which takes too long for a single unloading and reduces the overall production line yield. Summary of the Invention
[0003] The purpose of this application is to provide a wafer transfer robotic wrist joint mechanism, a robotic arm, and a calibration method, which have the effects of automatic station calibration, rapid wafer unloading, and buffering, and can significantly reduce costs.
[0004] In a first aspect, this application provides a wafer transfer mechanical wrist joint mechanism, including a wrist connection base, an end fork, and a flexible calibration and detection component; The wrist connection base is used to connect to the end of the robotic arm, and the end fork is used to carry and transfer the wafer; The flexible calibration and detection component includes an elastic substrate, a reset component, and a trigger component; the elastic substrate includes a fixed mounting section whose upper end is connected to the wrist connecting base, and a sensing swing section whose lower end is connected to the end plate fork; there is a swing gap between the fixed mounting section and the sensing swing section arranged along the XY plane, and the fixed mounting section and the sensing swing section are connected by a connecting thin wall extending along the Z direction, so that the sensing swing section can swing relative to the fixed mounting section; The triggering component includes a micro switch disposed on the fixed mounting section and a locking pin disposed on the sensing swing section. When the sensing swing section swings, it can drive the locking pin to trigger the micro switch. The reset component is disposed between the fixed mounting section and the sensing swing section. After the force driving the sensing swing section to swing disappears, the reset component can restore the sensing swing section to its initial position. It also includes a control system, which is electrically connected to the micro switch and is used to collect the coordinates of each axis of the robot at the moment of triggering.
[0005] In a preferred embodiment, the elastic matrix is integrally formed, and the connecting thin wall is an integral milled cut-out structure, formed by the material retained between two circular milled cut-outs on both sides.
[0006] In a preferred embodiment, the thickness of the narrowest part of the connecting thin wall is 0.4 mm to 0.8 mm.
[0007] In a preferred embodiment, the sensing swing segment has a base plate disposed along the XY plane and a boss disposed along the Z direction on the base plate; The base plate extends below the fixed mounting section, thereby creating a swing gap between the base plate and the fixed mounting section; The boss is disposed opposite to the fixed mounting section, the locking pin is disposed on the boss, and one end of the reset assembly abuts against the boss.
[0008] In a preferred embodiment, a limiting pin is provided at the corner opposite to the fixed mounting section of the base plate, and a limiting hole matching the limiting pin is provided in the fixed mounting section; The inner dimension of the limiting hole is larger than the outer dimension of the limiting pin, so that the limiting pin can swing within the limiting hole.
[0009] In a preferred embodiment, in the initial state, a trigger gap of 0.05mm to 0.10mm is left between the locking pin and the contact of the micro switch.
[0010] In a preferred embodiment, the reset assembly includes a reset spring and a spring locking bolt; The spring locking bolt passes through and is fixed to the fixed mounting section, with its front end close to the boss; the return spring is sleeved on the spring locking bolt, and both ends of the return spring abut against the fixed mounting section and the boss respectively.
[0011] In a preferred embodiment, a circuit board is also integrated on the lower surface of the wrist connection base.
[0012] Secondly, this application provides a robotic arm, including the aforementioned wafer transfer robotic wrist joint mechanism.
[0013] Thirdly, this application also provides a calibration method for a robotic arm, comprising the following steps: After the calibration program is started, the robot arm controls the end fork to contact the lower plate stage at low speed from different directions in X and Y. Each time contact occurs, the end fork is forced to compress the inductive swing segment, triggering the micro switch, and the control system simultaneously records the current robot arm axis coordinates; After multiple multi-point samplings are completed, the host computer fits and generates the center coordinates and boundary reference of the lower stage, updates the motion control parameters, completes the calibration, and exits the calibration mode.
[0014] This application has the following beneficial effects: During calibration, the robotic arm impacts and samples at multiple points in multiple directions. The host computer automatically fits and calculates the precise reference position of the wafer unloading stage based on multiple sets of coordinate data, completing the fully automated station calibration. After calibration, the flexible calibration and detection component only retains the function of buffering and anti-collision, and no longer participates in the station alignment control. Relying on the fault tolerance range formed by the pre-calibrated coordinates, the robotic arm can move directly to the top of the workpiece stage to pick up the wafer, eliminating the fine alignment required for dock docking and shortening the wafer picking time.
[0015] This application replaces the four-quadrant calibration scheme, significantly reducing the overall cost; the fully automated wafer unloading process calibration can significantly reduce debugging costs; the dockless rapid wafer unloading process can improve production line capacity; the reset component in the flexible calibration and testing component forms an elastic buffer structure, absorbing impact loads throughout the calibration and mass production process, reducing wafer breakage and wear of mechanical parts; the calibration and testing, buffer limit structure are integrated into a narrow wrist space, reducing equipment downtime for maintenance. Attached Figure Description
[0016] To more clearly illustrate the technical solutions of the embodiments of this application, the accompanying drawings used in the embodiments will be briefly introduced below. It should be understood that the following drawings only show some embodiments of this application and should not be regarded as a limitation of the scope. For those skilled in the art, other related drawings can be obtained based on these drawings without creative effort.
[0017] Figure 1 An exploded view of a mechanical wrist joint mechanism provided in an embodiment of this application; Figure 2 An assembly diagram of the mechanical wrist joint mechanism provided in an embodiment of this application; Figure 3 This is a schematic diagram of a flexible calibration and testing component. Figure 4 A first-view schematic diagram of an elastic matrix; Figure 5 A schematic diagram of the elastic matrix from a second perspective; Figure 6 This is a third-view schematic diagram of an elastic matrix; Figure 7 Schematic diagram for calibrating an automated workstation; Numbering on the map: 1-First screw; 2-Second screw; 3-Wrist connection base; 4-Hexagonal stud; 5-Board; 6-Micro switch; 7-Spring locking bolt; 8-Reset spring; 9-Elastic substrate; 901-Fixed mounting section; 902-Inductive swing section; 903-Connecting thin wall; 904-Base plate; 905-Boss; 906-Swing gap; 10-Limit pin; 11-End plate fork; 12-Third screw; 13-Locking pin; 14-Fourth screw; 15-Fifth screw; 16-Nut; 17-Lower plate platform; A-Impact point. Detailed Implementation
[0018] To make the objectives, technical solutions, and advantages of the embodiments of this application clearer, the technical solutions of the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some, not all, of the embodiments of this application. The components of the embodiments of this application described and labeled in the accompanying drawings can generally be arranged and designed in various different configurations.
[0019] Therefore, the following detailed description of the embodiments of this application provided in the accompanying drawings is not intended to limit the scope of the claimed application, but merely to illustrate selected embodiments of the application. All other embodiments obtained by those skilled in the art based on the embodiments of this application without inventive effort are within the scope of protection of this application.
[0020] It should be noted that similar labels and letters in the following figures indicate similar items. Therefore, once an item is defined in one figure, it does not need to be further defined and explained in subsequent figures.
[0021] In the description of this application, it should be noted that the terms "center," "upper," "lower," "left," "right," "vertical," "horizontal," "inner," and "outer," etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings, or the orientation or positional relationship commonly used when the product of the invention is in use. They are used only for the convenience of describing this application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this application. In addition, the terms "first," "second," and "third," etc., are used only to distinguish descriptions and should not be construed as indicating or implying relative importance.
[0022] Furthermore, terms such as "horizontal," "vertical," and "sag" do not imply that components must be absolutely horizontal or suspended, but rather that they can be slightly tilted. For example, "horizontal" simply means that its direction is more horizontal relative to "vertical," and does not mean that the structure must be completely horizontal, but can be slightly tilted.
[0023] In the description of this application, it should also be noted that, unless otherwise expressly specified and limited, the terms "set up," "install," "connect," and "link" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal connection of two components. Those skilled in the art can understand the specific meaning of the above terms in this application based on the specific circumstances.
[0024] The following detailed description of some embodiments of this application is provided in conjunction with the accompanying drawings. Unless otherwise specified, the following embodiments and features can be combined with each other.
[0025] like Figures 1-3 As shown, this embodiment first provides a wrist joint mechanism for wafer transfer machinery, mainly including a wrist connection base 3, an end fork 11, and a flexible calibration and detection component. In this embodiment and the accompanying drawings, the Z-axis is the axial direction of the wrist connection base 3, the XY plane is perpendicular to the Z-axis, and Rz represents rotation around the Z-axis.
[0026] The wrist connection base 3 is used to connect to the end of the robot arm, and the end fork 11 is used to carry and transfer the wafer.
[0027] like Figures 4-6 As shown, the flexible calibration and detection assembly includes an elastic substrate 9, a reset assembly, and a trigger assembly. The elastic substrate 9 includes a fixed mounting section 901 connected to the wrist connecting base 3 at its upper end, and a sensing swing section 902 connected to the end fork 11 at its lower end. There is a swing gap 906 between the fixed mounting section 901 and the sensing swing section 902 arranged along the XY plane, and the fixed mounting section 901 and the sensing swing section 902 are connected by a connecting thin wall 903 extending along the Z direction, so that the sensing swing section 902 can swing relative to the fixed mounting section 901 in the Rz direction.
[0028] The elastic substrate 9 is integrally molded, and the connecting thin wall 903 is an integral milled cut-out structure, formed by the material retained between two circular milled cutouts on both sides. The thickness of the connecting thin wall 903 at its narrowest point is 0.4mm~0.8mm, giving it both flexibility and connection rigidity. In this embodiment, the thickness of the connecting thin wall 903 at its narrowest point is 0.5mm.
[0029] The inductive swing section 902 has a base plate 904 disposed along the XY plane and a boss 905 disposed along the Z direction on the base plate 904; the base plate 904 extends to the underside of the fixed mounting section 901, thereby forming a swing gap 906 between the base plate 904 and the fixed mounting section 901.
[0030] A limiting pin 10 is provided at the corner opposite to the fixed mounting section 901 on the base plate 904. The fixed mounting section 901 is provided with a limiting hole that matches the limiting pin 10. The inner size of the limiting hole is slightly larger than the outer size of the limiting pin 10, so that the limiting pin 10 can swing within the limiting hole. The limiting hole can also limit the maximum swing amplitude of the limiting pin 10 in the Rz direction, so as to prevent the induction swing section 902 from overtravel and damaging the micro switch 6, the end plate fork 11 and the wafer.
[0031] More specifically, the wrist connecting base 3 is connected to the upper surface of the fixed mounting section 901 of the flexible calibration and detection assembly via three first screws 1, which can be M5×12 socket head cap screws. The end fork 11 is connected to the lower surface of the base plate 904 of the flexible calibration and detection assembly via three fourth screws 14, which can be M3×8 socket head cap screws.
[0032] The boss 905 is disposed opposite to the fixed mounting section 901. The triggering component includes a micro switch 6 disposed on the fixed mounting section 901 and a locking pin 13 disposed on the boss 905. When the sensing swing section 902 swings, it can drive the locking pin 13 to trigger the micro switch 6. Specifically, a mounting hole is provided on the boss 905, and a mounting slot communicating with the mounting hole is provided; the locking pin 13 is inserted into the mounting hole and fixed to the side wall of the boss 905 by the third screw 12. A V-shaped process groove is provided on the upper surface of the boss, and a threaded hole is opened on the surface of the V-shaped process groove. The boss portions on both sides of the mounting slot are connected by the fifth screw 15, thereby clamping the locking pin 13. The third screw 12 can be an H-type Phillips head countersunk screw, and the fifth screw 15 can be an M3×10 socket head cap screw.
[0033] In the initial state, the contact of the micro switch 6 is directly opposite the locking pin 13, and a trigger gap of 0.05mm to 0.10mm is maintained between the locking pin 13 and the contact of the micro switch 6. This trigger gap can be adjusted by using a feeler gauge to adjust the installation position of the micro switch. In this embodiment, a trigger gap of 0.08mm is maintained between the locking pin 13 and the contact of the micro switch 6.
[0034] The reset assembly includes a reset spring 8 and a spring locking bolt 7. The spring locking bolt 7 passes through and is fixed to the fixed mounting section 901, with its front end near the boss 905. The reset spring 8 is sleeved on the spring locking bolt 7, and its two ends abut against the fixed mounting section 901 and the boss 905, respectively. Under normal conditions, the reset assembly keeps the sensing swing section 902 in its initial stationary position. After the force driving the sensing swing section 902 to swing disappears, the reset assembly can return the sensing swing section 902 to its initial position.
[0035] The board 5 is integrated and fixed to the lower surface of the wrist connection base 3 by four second screws 2, hexagonal studs 4, and nuts 16. The second screws 2 can be M3×8 socket head cap screws. The board 5 is the control system in this embodiment, electrically connected to the micro switch 6, and used to collect the coordinates of each axis of the robot arm at the moment of triggering.
[0036] The robotic arm provided in this embodiment includes the wrist joint mechanism of the wafer transfer robotic arm.
[0037] This embodiment also provides a calibration method for a robotic arm, including the following steps: like Figure 7 As shown, after the calibration program is started, the robot arm controls the end fork 11 to contact the lower stage 17 at low speed from different directions X and Y. Each contact, such as when the end fork 11 contacts the impact point A, compresses the induction swing section 902 to swing and triggers the micro switch 6, and the control system synchronously records the current robot arm axis coordinates; After multiple multi-point samplings are completed, the host computer fits and generates the center coordinates and boundary reference of the lower stage, updates the motion control parameters, completes the calibration, and exits the calibration mode.
[0038] The robotic arm performs impact sampling at multiple points along multiple directions. The host computer automatically fits and calculates the precise reference position of the lower stage based on multiple sets of coordinate data, completing the fully automated station calibration without manual intervention. After calibration, the flexible calibration and detection component only retains its buffer and anti-collision function and no longer participates in station alignment control. This mechanism adopts a single microswitch contact trigger calibration scheme, which differs from the traditional four-quadrant sensor calibration structure. This scheme relies on only a single microswitch to achieve all coordinate acquisition, eliminating the need for multiple sensors and supporting electrical components, significantly reducing the number of parts, material costs, wiring, and assembly costs. Moreover, the detection function is only activated in calibration modes during equipment installation, process switching, and coordinate drift correction.
[0039] After the workstation calibration is completed, the system stores the reference coordinates of the unloading stage 17. Mass production unloading operations do not require high-precision positioning and docking based on the workpiece dock structure. Relying on the pre-calibrated coordinates to form an alignment tolerance range, the unloading robot can move directly to the top of the workpiece stage to pick up the wafer, eliminating the fine alignment and trajectory fine-tuning steps required for dock docking, simplifying the robot's movement path, shortening the unloading time of a single wafer, and improving the machine's productivity.
[0040] If overshoot occurs during calibration and mass production wafer unloading, the thin-walled 903 in the flexible calibration and testing component and the reset spring 8 together absorb the impact force to avoid wafer breakage and scratches, and reduce wafer damage and wear of mechanical parts.
[0041] Furthermore, this solution adopts an integrated structure, integrating calibration detection and buffer limit structure into a narrow wrist space, reducing equipment downtime for maintenance.
[0042] The above are merely preferred embodiments of this application and are not intended to limit this application. Various modifications and variations can be made to this application by those skilled in the art. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of this application should be included within the protection scope of this application.
Claims
1. A mechanical wrist joint mechanism for wafer transfer, characterized in that, Includes wrist connection base, end fork, and flexible calibration and detection components; The wrist connection base is used to connect to the end of the robotic arm, and the end fork is used to carry and transfer the wafer; The flexible calibration and detection component includes an elastic substrate, a reset component, and a trigger component; the elastic substrate includes a fixed mounting section whose upper end is connected to the wrist connecting base, and a sensing swing section whose lower end is connected to the end plate fork; there is a swing gap between the fixed mounting section and the sensing swing section arranged along the XY plane, and the fixed mounting section and the sensing swing section are connected by a connecting thin wall extending along the Z direction, so that the sensing swing section can swing relative to the fixed mounting section; The triggering component includes a micro switch disposed on the fixed mounting section and a locking pin disposed on the sensing swing section. When the sensing swing section swings, it can drive the locking pin to trigger the micro switch. The reset component is disposed between the fixed mounting section and the sensing swing section. After the force driving the sensing swing section to swing disappears, the reset component can restore the sensing swing section to its initial position. It also includes a control system, which is electrically connected to the micro switch and is used to collect the coordinates of each axis of the robot at the moment of triggering.
2. The wafer transfer mechanical wrist joint mechanism according to claim 1, characterized in that, The elastic matrix is integrally formed, and the connecting thin wall is an integral milled cut structure, formed by the material retained between two circular milled cuts on both sides.
3. The wafer transfer mechanical wrist joint mechanism according to claim 1 or 2, characterized in that, The thickness of the narrowest part of the connecting thin wall is 0.4mm to 0.8mm.
4. The wafer transfer mechanical wrist joint mechanism according to claim 1, characterized in that, The inductive swing section has a base plate arranged along the XY plane and a boss arranged along the Z direction on the base plate; The base plate extends below the fixed mounting section, thereby creating a swing gap between the base plate and the fixed mounting section; The boss is disposed opposite to the fixed mounting section, the locking pin is disposed on the boss, and one end of the reset assembly abuts against the boss.
5. The wafer transfer mechanical wrist joint mechanism according to claim 4, characterized in that, A limiting pin is provided at the corner opposite to the fixed installation section of the base plate, and a limiting hole matching the limiting pin is provided in the fixed installation section; The inner dimension of the limiting hole is larger than the outer dimension of the limiting pin, so that the limiting pin can swing within the limiting hole.
6. The wafer transfer mechanical wrist joint mechanism according to claim 4, characterized in that, In the initial state, there is a trigger gap of 0.05mm to 0.10mm between the locking pin and the contact of the micro switch.
7. The wafer transfer mechanical wrist joint mechanism according to claim 4, characterized in that, The reset assembly includes a reset spring and a spring locking bolt; The spring locking bolt passes through and is fixed to the fixed mounting section, with its front end close to the boss; the return spring is sleeved on the spring locking bolt, and both ends of the return spring abut against the fixed mounting section and the boss respectively.
8. The wafer transfer mechanical wrist joint mechanism according to claim 1, characterized in that, The lower surface of the wrist connection base is also integrated with a circuit board.
9. A robotic arm, characterized in that, Includes the wafer transfer mechanical wrist joint mechanism as described in any one of claims 1 to 8.
10. A calibration method for a robotic arm as described in claim 9, characterized in that, Includes the following steps: After the calibration program is started, the robot arm controls the end fork to contact the lower plate stage at low speed from different directions in X and Y. Each time contact occurs, the end fork is forced to compress the inductive swing segment, triggering the micro switch, and the control system simultaneously records the current robot arm axis coordinates; After multiple multi-point samplings are completed, the host computer fits and generates the center coordinates and boundary reference of the lower stage, updates the motion control parameters, completes the calibration, and exits the calibration mode.