Wafer automatic edge searching and centering multi-angle exposure device and method

Abstract

The invention discloses a wafer automatic edge searching and centering multi-angle exposure device and method, and the device comprises an exposure cavity, and an exposure unit and an edge searching unit which are arranged in the exposure cavity, and also comprises: a lifting mechanism which directly faces the exposure unit, is arranged at an interval, and comprises a lifting driving module and a lifting bearing part arranged at the top end of the lifting driving module; the translation rotating mechanism comprises a translation module and a rotating module arranged on the translation module in a sliding mode, the top of the rotating module is further rotationally connected with a rotating bearing part, and the rotating axis of the rotating bearing part is parallel to the lifting axis of the lifting bearing part; the translation module drives the rotating module to do horizontal linear motion between the exposure unit and the corresponding station of the lifting mechanism, and the edge searching unit is arranged between the exposure unit and the lifting mechanism and is arranged on one side of the rotating module in an offset manner. According to the device, translation, rotation and lifting mechanisms are integrated, in-situ mechanical centering in a wafer cavity is achieved, eccentricity is eliminated, and the precision and efficiency of multi-angle edge exposure are ensured.

Description

Technical Field

[0001] This invention relates to the field of semiconductor photolithography technology, and particularly to a wafer automatic edge-finding and alignment multi-angle exposure apparatus and method. Background Technology

[0002] Exposure processes in semiconductor manufacturing encompass multiple high-tech industries, including photolithography, micro-nano fabrication, and precision manufacturing. Their core technologies are based on optical, electron beam, or maskless direct writing principles, used to achieve pattern transfer at the micrometer to nanometer scale. If a process requires exposing the perimeter of a wafer edge, with multiple exposure areas evenly distributed at an angle around this edge, the angle and center of the wafer's notch point must first be determined. Typically, an edge-finding and alignment unit is incorporated into the equipment to perform edge-finding and alignment operations.

[0003] The exposure process requires precise marking of the notch angles and positions on the wafer, necessitating edge finding and alignment. Typically, the equipment includes an edge-finding calibration unit for this operation. However, if this calibration is an external unit separate from the process chamber, even after the wafer's angle and center position are determined, the process of transporting it to the exposure unit by the wafer arm places extremely high demands on the arm's precision. If positional deviations occur, additional units are needed for verification and detection, requiring a return trip to repeat the edge-finding and alignment operation. This significantly impacts production efficiency.

[0004] Integrating the edge-finding calibration unit into the exposure unit still requires an arm to lift and hold the wafer after its angle and center have been determined. The motor-driven suction cup is then positioned at the center of the wafer, and the arm places the wafer back onto the suction cup. This process is complex and time-consuming, impacting production efficiency.

[0005] Another approach involves edge-finding calibration to locate the wafer's notch and center position, maintaining the wafer's original position on the motor chuck. Then, a vision-based solution controls the synchronized movement of the motor's single-axis offset and rotation to compensate for eccentricity, ensuring uniformity in wafer indexing exposure. This approach requires mature vision systems and algorithms, but excessively high speeds in dual-axis linkage can negatively impact stability. Furthermore, arranging mechanical alignment units within the cavity cannot meet the precision requirements of the exposure process due to wafer dimensional variations and deformation.

[0006] Therefore, this application aims to propose an exposure device and method that can independently complete wafer physical edge finding and secondary alignment within the process cavity, thereby avoiding repeated handling errors by robotic arms and the instability of dynamic visual compensation. Summary of the Invention

[0007] To address the problems existing in the prior art, this invention proposes a wafer automatic edge finding and alignment multi-angle exposure device and method.

[0008] According to a first aspect of this application, a wafer automatic edge-finding and alignment multi-angle exposure apparatus is proposed, comprising an exposure cavity and an exposure unit and an edge-finding unit disposed within the exposure cavity, and further comprising: The lifting mechanism is positioned opposite the exposure unit and spaced apart, and includes a lifting drive module and a lifting support component located at the top of the lifting drive module; The translation and rotation mechanism includes a translation module and a rotation module slidably mounted on the translation module. A rotation bearing is rotatably connected to the top of the rotation module. The rotation axis of the rotation bearing is parallel to the lifting axis of the lifting bearing. The translation module drives the rotation module to perform horizontal linear motion between the exposure unit and the corresponding workstation of the lifting mechanism. The edge-finding unit is located between the exposure unit and the lifting mechanism and is offset to one side of the rotation module.

[0009] By adopting the above technical solution, this application arranges a lifting mechanism with vacuum adsorption function inside the exposure unit and cooperates with the rotating carrier. This cavity-integrated architecture allows the wafer edge finding and alignment process to be completed directly inside the exposure cavity without the intervention of an external robot. Compared with the existing technology of external edge finding and alignment plus robot arm handling or internal robot secondary gripping, this structure significantly shortens the process operation time and eliminates the accuracy loss during the handling process. The structure of this application utilizes the rotating module to take on the dual functions of edge finding scanning and exposure rotation, while delegating the lifting action to an independent lifting mechanism. Without the intervention of an external robot, the automatic flow of the wafer between edge finding, alignment, and exposure stations can be completed by the single-axis translation of the translation module, which improves the integration of the equipment.

[0010] Preferably, the lifting drive module includes a lifting base, a first lifting motor, and a lifting plate. The lifting base is located on the inner bottom surface of the exposure cavity. The first lifting motor is located at the lower part of the lifting base, and the output end of the first lifting motor passes vertically upward through the lifting base and is connected to the bottom of the lifting plate. The lifting base has a vertical first lifting guide rail on the back of the lifting plate, and a first lifting slider is slidably mounted on the first lifting guide rail. The back of the lifting plate is connected to the first lifting slider.

[0011] By adopting the above technical solution, using a sunken motor layout and a back rail support structure, the problem of Z-axis travel within the limited exposure cavity space is effectively solved. This connection method has extremely high bending and torsional rigidity, ensuring the horizontal orientation stability of the wafer at the moment of handover.

[0012] In a further preferred embodiment, the lifting base has a vertical mounting plate formed on the back side of the lifting plate, the first lifting guide rail is set on the side of the mounting plate facing the lifting plate, and a distance measuring sensor is also provided on the top of the mounting plate.

[0013] By adopting the above technical solution, a non-contact ranging sensor is established at the junction of the wafer edge region and the lifting mechanism. Specifically, the sensing point of the ranging sensor and the adsorption point at the top of the lifting support are located on concentric circles with the radius of the center of the wafer when it is searching for the edge. Therefore, the ranging sensor can measure the end-plane flatness data and distance of the wafer during rotation and provide feedback to ensure the height requirement of the lifting support for the wafer adsorption. At the same time, when installing the rotating support, the ranging sensor can also replace the dial indicator to detect the end-plane parallelism of the rotating support installation and whether it is installed in place. It can also play an auxiliary role in the overall installation and commissioning process of the equipment.

[0014] Preferably, the diameter of the bearing surface of the rotating carrier is smaller than the diameter of the wafer to be exposed, so that the edge region of the wafer is suspended when it is adsorbed; wherein, when the edge region is located at the station of the lifting carrier, the horizontal projection of the bearing center of the lifting carrier is located within the edge region.

[0015] By adopting the above technical solution, the edge area of ​​the wafer that needs to be inspected is suspended by the diameter difference, avoiding interference between the lifting support and the rotating support when the lifting support adsorbs the edge of the wafer, while not weakening the adsorption capacity of the rotating support for the wafer. The lifting support only needs to adsorb the edge area of ​​the wafer, completely avoiding mechanical contact with the effective pattern area in the center of the wafer, and eliminating the process risk of suction cup marks or back scratches.

[0016] Preferably, the top surfaces of the lifting support and the rotating support each have at least one vacuum adsorption port for adsorbing wafers, the top surface of the rotating support is provided with a plurality of concentric pressure equalization grooves arranged around the vacuum adsorption port, and the adjacent pressure equalization grooves are connected by openings, and the top surface of the lifting support is provided with a buffer sealing ring surrounding the vacuum adsorption port.

[0017] By adopting the above technical solution, the buffer sealing ring can be an O-ring made of fluororubber, which utilizes its excellent buffering effect to adapt to the slight deformation of the wafer. At the same time, the rotating carrier can be made of PETP material and its end face is polished to a surface finish of less than R0.8. This treatment ensures that even if the wafer is slightly lifted by the lifting mechanism during centering movement, the surface of the rotating carrier can maintain excellent smoothness, without jamming due to excessive friction or vacuum drop, thus ensuring the smoothness and positional accuracy of the centering movement process.

[0018] Preferably, the translation module includes a guide rail base, a translation guide rail, and a translation motor. The guide rail base is located on the inner bottom surface of the exposure cavity. The stroke of the translation guide rail is parallel to the horizontal line connecting the exposure unit and the lifting mechanism. The translation motor is located at one end of the translation guide rail, and the output end of the translation motor is connected to the translation slider of the translation guide rail. The bottom of the rotation module is connected to the translation slider.

[0019] By adopting the above technical solution, the guide rail base serves as the base of the translation module. The translation direction of the rotating module is limited by the horizontally set translation guide rail. The translation motor drives the translation slider to move by being coaxially connected to the ball screw of the translation guide rail or by a synchronous belt, ensuring that the translation movement is efficient and accurate.

[0020] Preferably, the rotating module includes a motor base, a rotary motor, and an origin detection component. The motor base is slidably mounted on the translation module. The rotary motor is mounted on the lower part of the motor base, and the output end of the rotary motor passes vertically upward through the top surface of the motor base and is connected to the center of the bottom surface of the rotating support. The origin detection component includes an origin sensor disposed on the edge of the top surface of the motor base and a sensing baffle disposed on the bottom surface of the rotating support. The sensing baffle cooperates with the origin sensor and is configured to determine the zero reference point of the rotating support.

[0021] By adopting the above technical solution, the motor base is responsible for sliding connection with the translation module, and the rotary motor is embedded in the lower part of the motor base. Its output end is connected to the bottom surface of the rotating support, thereby directly driving the rotation of the rotating support. The cooperation of the origin sensor and the sensing baffle ensures that the rotary motor can find a unique zero reference point after each power-on. Under the reference determined by the origin detection component, the rotary support can be driven to move to a position concentric with the actual center of the wafer according to the calculated eccentricity. This mechanical secondary concentricity correction directly eliminates the wafer loading error and ensures that the wafer and the rotating support are always in a concentric state during rotary exposure.

[0022] Preferably, the exposure chamber has a feed port for wafers to pass through on one side wall near the lifting mechanism, and also includes a sealing cylinder set on the inner wall of the exposure chamber. The output end of the sealing cylinder is connected to a sealing plate, and the sealing cylinder drives the sealing plate to switch between an avoidance position and a shielding position. When in the shielding position, the sealing plate seals and covers the feed port. The bottom surface of the exposure chamber is also provided with an exhaust box, which is configured to connect to an external negative pressure system and discharge particles generated in the exposure chamber.

[0023] By adopting the above technical solution, cable drag chains and other storage structures are installed inside the exposure chamber to accommodate the circuitry. When the moving sliders and drag chains inside the exposure chamber move, particles are generated due to friction. The exhaust box can directly discharge these particles to the plant processing end, ensuring the cleanliness required by the production environment and promoting the stability and efficiency of production. The combination of the closed cylinder and the sealing plate enables the exposure chamber to have a sealable feed port, which does not cause physical obstruction during feeding. After the wafer loading is completed, the feed port is immediately blocked to ensure the airtightness of the process operation and avoid interference from the external environment.

[0024] Preferably, the exposure unit includes a mounting bracket vertically mounted on the bottom surface of the exposure cavity, a second lifting guide rail extending vertically on the mounting bracket, and a second lifting slider slidably mounted on the second lifting guide rail; a second lifting motor is provided at one end of the second lifting guide rail, and the output end of the second lifting motor is connected to the second lifting slider in a transmission connection; a horizontal adjustment seat is connected to the second lifting slider, and the optical module of the exposure unit is mounted on the horizontal adjustment seat.

[0025] By adopting the above technical solution, the second lifting guide rail can adjust the vertical position of the optical module. The optical module is installed on the second lifting guide rail along with the horizontal adjustment seat. At the same time, the horizontal position of the optical module can also be adjusted (the translation module is a horizontal longitudinal displacement). During the initial debugging of the equipment, the exposure point of the optical module can be adjusted according to the situation, and it is convenient for later maintenance.

[0026] According to a second aspect of this application, an automated wafer edge-finding and alignment exposure method is proposed, employing the exposure apparatus as described above, comprising: S1: The translation module drives the rotation module to move to the loading and unloading station near the lifting mechanism. The external robot places the wafer to be exposed on the rotating carrier, and the rotating carrier uses negative pressure to adsorb and fix the wafer. S2: The rotating module carries the wafer to the edge-finding station corresponding to the edge-finding unit. The rotating module drives the rotating carrier to rotate the wafer. The edge-finding unit obtains the edge data of the wafer and calculates the eccentricity of the actual center of the wafer relative to the rotation center of the rotating carrier. S3: The rotating module drives the wafer to rotate, so that the actual center of the wafer, the rotation center of the rotating support component, and the support center of the lifting support component are on the same straight line; S4: The rotating module moves the edge area of ​​the wafer to the adjustment position where the lifting mechanism is located. The lifting drive module controls the lifting carrier to rise and uses negative pressure to adsorb the edge area. It is determined whether the lifting carrier has adsorbed the wafer in place according to the negative pressure threshold. After adsorption, the rotating carrier releases the negative pressure adsorption on the wafer. The translation module drives the rotating module to perform linear displacement compensation according to the eccentricity, so that the rotation center coincides with the actual center of the circle. The rotating carrier re-adsorbs the wafer, and the lifting carrier releases the adsorption and resets. S5: The rotating module carries the wafer toward the exposure unit, so that the edge area is located in the exposure station covered by the exposure unit, and performs single-angle / multi-angle exposure operations; S6: After exposure is complete, the rotating module carries the wafer to the loading and unloading station, the rotating support is released from adsorption, and the external robot removes the wafer.

[0027] By adopting the above technical solution, after wafer loading, the rotating support component applies negative pressure to the wafer and moves it to the edge-finding station for edge-finding operation. It locates the wafer's NOTCH point and actual center (calculating the eccentricity). Then, the rotating support component controls the wafer's rotation until the actual center, the rotation center of the rotating support component, and the support center of the lifting support component are aligned. At this point, the wafer's displacement is controlled until the edge area is above the lifting support component. The lifting support component applies negative pressure to the edge area, thus supporting one side of the wafer's edge. The rotating support component can then... The negative pressure adsorption is released, and the rotating carrier always supports the bottom surface of the wafer without affecting the translation of the rotating carrier. At this time, the rotating carrier is translated to a position concentric with the wafer before the negative pressure adsorption is activated again. This completes both the mechanical alignment operation and the marking of the wafer's NOTCH point. Finally, the wafer is moved to the exposure station for single-angle or multi-angle exposure operations. No external robotic arm is required for secondary operation. The above processes can be completed in one go in an independent exposure chamber. This method has high integration and ensures the accuracy requirements of wafer edge alignment and process stability.

[0028] Compared with the prior art, the beneficial effects of this application are as follows: This application integrates a translation module, a rotation module, and a lifting mechanism within the exposure chamber, directly utilizing the cooperation between the modules to complete the wafer edge finding and mechanical alignment operations inside the chamber. This method uses the linear motion of the translation module to compensate for the wafer's eccentricity, and, in conjunction with the lifting mechanism's adsorption support for the wafer edge, achieves physical alignment between the actual center of the wafer and the rotation center. This approach replaces the traditional external edge finding plus robotic arm handling mode, eliminating vibration errors during handling and avoiding the instability of relying solely on software algorithms for dynamic compensation. By eliminating physical eccentricity before exposure, it ensures that the wafer remains concentric with the rotating device during subsequent rotational exposure, ensuring the uniformity of lines and process accuracy of multi-angle edge exposure, significantly improving production efficiency. Attached Figure Description

[0029] The accompanying drawings are included to provide a further understanding of the embodiments and are incorporated in and constitute a part of this specification. The drawings illustrate embodiments and, together with the description, serve to explain the principles of the invention. Other embodiments and many anticipated advantages of the embodiments will be readily recognized as they become better understood through reference to the following detailed description. Elements in the drawings are not necessarily to scale. The same reference numerals refer to corresponding similar elements.

[0030] Figure 1 This is a structural perspective view of the automatic edge-finding and centering multi-angle exposure apparatus according to an embodiment of this application; Figure 2This is an exploded view of the structure of the automatic edge-finding and centering multi-angle exposure device according to a specific embodiment of this application; Figure 3 This is a schematic diagram of the wafer exposure area according to a specific embodiment of this application; Figure 4 This is a schematic diagram of the lifting mechanism structure according to a specific embodiment of this application; Figure 5 This is a schematic diagram of the cooperation between the translation module and the rotation module according to a specific embodiment of this application; Figure 6 This is a schematic diagram of the exposure unit structure according to a specific embodiment of this application; Figure 7 This is a flowchart of an automatic edge-finding and alignment exposure method for wafers according to an embodiment of this application.

[0031] The meaning of each number in the diagram: Exposure cavity 01, Exposure unit 02, Edge finding unit 03, Lifting drive module 04, Lifting support component 05, Translation module 06, Rotation module 07, Rotation support component 08, Wafer 09, Exposure area 10, Lifting base 11, First lifting motor 12, Lifting plate 13, First lifting guide rail 14, First lifting slider 15, Mounting plate 16, Distance sensor 17, Lead screw nut 18, Limit block 19, Guide rail seat 20, Translation guide rail 21, Translation motor 22. Machine, translation slider, 23. Motor base, 24. Rotary motor, 25. Origin sensor, 26. Induction baffle, 27. Vacuum adsorption port, 28. Pressure equalization groove, 29. Buffer sealing ring, 30. Feed port, 31. Sealing cylinder, 32. Sealing plate, 33. Exhaust box, 34. Cable chain, 35. Mounting bracket, 36. Second lifting guide rail, 37. Second lifting slider, 38. Second lifting motor, 39. Horizontal adjustment seat, 40. Optical module, 41. Limit sensor, 42. Trigger, 43. Detailed Implementation

[0032] In the following detailed description, reference is made to the accompanying drawings, which form part of the detailed description and are illustrated by specific illustrative embodiments in which the invention may be practiced. In this regard, directional terms such as “top,” “bottom,” “left,” “right,” “up,” “down,” etc., are used with reference to the orientation of the described figures. Because components of the embodiments can be positioned in several different orientations, directional terms are used for illustrative purposes and are by no means limiting. It should be understood that other embodiments may be utilized or logical changes may be made without departing from the scope of the invention. Therefore, the following detailed description should not be taken in a limiting sense, and the scope of the invention is defined by the appended claims.

[0033] According to the first aspect of this application, a wafer automatic edge-finding and alignment multi-angle exposure device is proposed. Figure 1A structural perspective view of an automatic edge-finding and centering multi-angle exposure apparatus according to an embodiment of this application is shown. Figure 2 An exploded view of the structure of an automatic edge-finding and centering multi-angle exposure apparatus according to a specific embodiment of this application is shown, as follows: Figure 1-2 As shown, Figure 1 The internal structure of the exposure cavity 01 is shown using a perspective view. The device includes the exposure cavity 01, an exposure unit 02 and an edge-finding unit 03 disposed within the exposure cavity 01, and also includes: The lifting mechanism is positioned opposite the exposure unit 02 and spaced apart, and includes a lifting drive module 04 and a lifting support component 05 located at the top of the lifting drive module 04. The translation and rotation mechanism includes a translation module 06 and a rotation module 07 slidably disposed on the translation module 06. A rotation support member 08 is rotatably connected to the top of the rotation module 07. The rotation axis of the rotation support member 08 is parallel to the lifting axis of the lifting support member 05. The translation module 06 drives the rotation module 07 to perform horizontal linear motion between the exposure unit 02 and the corresponding workstation of the lifting mechanism. The edge-finding unit 03 is disposed between the exposure unit 02 and the lifting mechanism and is offset to one side of the rotation module 07.

[0034] Furthermore, the edge-finding unit 03 is not limited to being set on one side of the rotating module 07. In a specific embodiment, the edge-finding unit 03 can be set on the same side as the exposure unit 02, with the two set at intervals, respectively corresponding to the edge-finding process and the exposure process, and there will be no functional interference between the two.

[0035] Specifically, wafer 09 is loaded by an external robotic arm. The robotic arm first places wafer 09 on a rotating support 08. The rotating support 08 activates a vacuum to adsorb wafer 09. Then, the translation module 06 drives the rotation module 07 to move to the edge-finding station where the edge-finding unit 03 is located. The rotation module 07 drives the rotating support 08 to rotate wafer 09 and start the edge-finding operation. After the edge-finding is completed, the external control system can calculate the NOTCH point and the actual center position of wafer 09. The rotating support 08 rotates again, aligning the actual center of the wafer 09, the rotation center of the rotating support 08, and the support center of the lifting support 05 in a straight line before stopping the rotation. Then, the wafer 09 is moved towards the lifting mechanism. The translation stops when the edge area of ​​the wafer 09 is directly above the lifting support 05. The lifting mechanism drives the lifting support 05 to rise and adsorb the edge area of ​​the wafer 09. The vacuum values ​​before and after the lifting support 05 adsorbs the wafer 09 are generally -35 ~ -40 kPa and -80 ~ -90 kPa, respectively. Therefore, a vacuum threshold can be set based on these two values. By judging the relationship between the vacuum value of the lifting support 05 and the threshold, it can be determined whether the lifting support 05 has risen to the correct position and adsorbed the wafer 09. Then, the next alignment operation between the wafer 09 and the lifting support 05 is performed. Specifically, the lifting support 05 holds the wafer 09. Based on the distance change of the rotating support 08 before and after the vacuum is released, the appropriate height of the lifting support 05 can be simultaneously calibrated to ensure the stability of the wafer 09 edge-finding and centering process in subsequent production. If the rotating support 08 becomes loose during long-term operation, and the distance and parallelism of the wafer 09 change after being held, timely warning feedback can be provided for maintenance. After the lifting support 05 adsorbs the edge area of ​​the wafer 09, the rotating support 08 releases the vacuum adsorption of the wafer 09. However, the supporting force of the lifting support 05 on the bottom of the wafer 09 does not disappear at this time, so the wafer 09 will not fall. Then the rotating module 07 continues to move along the translation module 06, aligning the rotation center of the rotating support 08 with the actual center of the wafer 09 before reactivating the vacuum adsorption, re-adsorbing the wafer 09, and completing the centering operation. At this time, the lifting support 05 releases the vacuum adsorption and descends to detach from the wafer 09, returning to the starting position. Figure 3 A schematic diagram of the wafer exposure area according to a specific embodiment of this application is shown, such as... Figure 1-3 As shown, the above steps complete the system's marking of the concentricity requirements of wafer 09 and rotating support 08 and the position of the NOTCH point, thereby enabling the next step of moving wafer 09 to the exposure station. Exposure unit 02 performs the exposure process on several evenly distributed exposure areas 10 around the edge of wafer 09.

[0036] This application arranges a lifting mechanism with vacuum adsorption function inside the exposure unit 02 and cooperates with the rotating support component 08. This cavity-integrated architecture allows the edge finding and alignment process of the wafer 09 to be completed directly within the exposure cavity 01 without the intervention of an external robot. Compared with the existing technology of external edge finding and alignment plus robot arm handling or internal robot secondary gripping, this structure significantly shortens the process operation time and eliminates the accuracy loss during the handling process. The structure of this application utilizes the rotating module 07 to take on the dual functions of edge finding scanning and exposure rotation, while delegating the lifting action to an independent lifting mechanism. Without the intervention of an external robot, the automatic flow of the wafer 09 between edge finding, alignment, and exposure stations can be completed by the single-axis translation of the translation module 06, which improves the integration of the equipment.

[0037] Figure 4 A schematic diagram of the lifting mechanism structure according to a specific embodiment of this application is shown, such as... Figure 1-4 As shown, the lifting drive module 04 includes a lifting base 11, a first lifting motor 12, and a lifting plate 13. The lifting base 11 is located on the inner bottom surface of the exposure cavity 01. The first lifting motor 12 is located at the lower part of the lifting base 11, and the output end of the first lifting motor 12 passes vertically upward through the lifting base 11 and is connected to the bottom of the lifting plate 13. The lifting base 11 has a vertical first lifting guide rail 14 on the back of the lifting plate 13, and a first lifting slider 15 is slidably mounted on the first lifting guide rail 14. The back of the lifting plate 13 is connected to the first lifting slider 15.

[0038] The recessed motor layout and back rail support structure effectively solve the problem of Z-axis travel within the limited space of the exposure cavity 01. This connection method has extremely high bending and torsional rigidity, ensuring the horizontal attitude stability of wafer 09 at the moment of handover.

[0039] In a further preferred embodiment, the lifting base 11 has a vertical mounting plate 16 formed on the back side of the lifting plate 13, the first lifting guide rail 14 is disposed on the side of the mounting plate 16 facing the lifting plate 13, and the top of the mounting plate 16 is also provided with a distance measuring sensor 17.

[0040] Specifically, the ranging sensor 17 can measure the parallelism and deformation of wafer 09 during production, thereby establishing an early warning feedback mechanism, which has a positive effect on production.

[0041] A non-contact ranging sensor 17 is installed at the junction of the edge region of wafer 09 and the lifting mechanism. The sensing point of the ranging sensor 17 and the adsorption point at the top of the lifting support 05 are located on the same concentric circle with the radius of the center of the wafer 09 when it seeks the edge. Therefore, the ranging sensor 17 can measure the end jump flatness data and distance of the wafer 09 when it rotates and provide feedback to ensure the height requirement of the lifting support 05 for adsorption of the wafer 09. At the same time, when installing the rotating support 08, the ranging sensor 17 can also replace the dial indicator to detect the end jump parallelism of the rotating support 08 and whether it is installed in place. It can also play an auxiliary role in the overall installation and commissioning of the equipment.

[0042] Furthermore, the output end of the first lifting motor 12 is connected to a lead screw nut 18, which cooperates with the bottom of the lifting plate 13, thereby enabling the first lifting motor 12 to drive the lifting plate 13 to lift. At the same time, the two sides of the lifting base 11 have limit blocks 19 that extend upward and bend inward. When the lifting plate 13 is raised to the highest point, the limit blocks 19 will abut against the bottom edge of the lifting plate 13 to prevent overtravel.

[0043] Figure 5 A schematic diagram of the cooperation between the translation module and the rotation module according to a specific embodiment of this application is shown, such as... Figure 1-5 As shown, the translation module 06 includes a guide rail base 20, a translation guide rail 21, and a translation motor 22. The guide rail base 20 is located on the inner bottom surface of the exposure cavity 01. The stroke of the translation guide rail 21 is parallel to the horizontal line connecting the exposure unit 02 and the lifting mechanism. The translation motor 22 is located at one end of the translation guide rail 21, and the output end of the translation motor 22 is connected to the translation slider 23 of the translation guide rail 21. The bottom of the rotation module 07 is connected to the translation slider 23.

[0044] The guide rail base 20 serves as the base of the translation module 06. The translation direction of the rotating module 07 is defined by the horizontally set translation guide rail 21. The translation motor 22 drives the translation slider 23 to move by being coaxially connected to the ball screw of the translation guide rail 21 or by a synchronous belt (the second lifting motor 39 and the second lifting guide rail 37 can also adopt the same transmission form). This ensures that the translation movement is efficient and accurate.

[0045] Preferably, the rotating module 07 includes a motor base 24, a rotary motor 25, and an origin detection component. The motor base 24 is slidably mounted on the translation module 06 (specifically mounted on the translation slider 23). The rotary motor 25 is mounted on the lower part of the motor base 24, and the output end of the rotary motor 25 passes vertically upward through the top surface of the motor base 24 and is connected to the center of the bottom surface of the rotating support 08. The origin detection component includes an origin sensor 26 disposed on the edge of the top surface of the motor base 24 and a sensing baffle 27 disposed on the bottom surface of the rotating support 08. The sensing baffle 27 cooperates with the origin sensor 26 and is configured to determine the zero reference point of the rotating support 08.

[0046] The motor mount 24 is slidably connected to the translation module 06, and the rotary motor 25 is embedded in the lower part of the motor mount 24. Its output end is connected to the bottom surface of the rotary support 08, thereby directly driving the rotation of the rotary support 08. The cooperation of the origin sensor 26 and the sensing baffle 27 ensures that the rotary motor 25 can find a unique zero reference point after each power-on. Under the reference determined by the origin detection component, the rotary support 08 can be driven to move to a position concentric with the actual center of the wafer 09 according to the calculated eccentricity. This mechanical secondary concentricity correction directly eliminates the loading error of the wafer 09 and ensures that the wafer 09 and the rotary support 08 are always concentric during rotary exposure.

[0047] Preferably, the diameter of the bearing surface of the rotating support 08 is smaller than the diameter of the wafer 09 to be exposed, so that the edge region of the wafer 09 is suspended when it is adsorbed; wherein, when the edge region is at the station where the lifting support 05 is located, the horizontal projection of the bearing center of the lifting support 05 is located within the edge region.

[0048] By using the diameter difference, the edge area of ​​wafer 09 that needs to be inspected is suspended, avoiding interference between the lifting support 05 and the rotating support 08 when the lifting support 05 adsorbs the edge of wafer 09. At the same time, it does not weaken the adsorption capacity of the rotating support 08 on wafer 09. The lifting support 05 only needs to adsorb the edge area of ​​wafer 09, completely avoiding mechanical contact with the effective pattern area in the center of wafer 09, and eliminating the process risk of suction cup imprints or back scratches.

[0049] Preferably, the top surfaces of the lifting support 05 and the rotating support 08 are respectively provided with at least one vacuum adsorption port 28 for adsorbing the wafer 09. The top surface of the rotating support 08 is provided with a plurality of concentric pressure equalization grooves 29 arranged around the vacuum adsorption port 28. The adjacent pressure equalization grooves 29 are connected by openings. The top surface of the lifting support 05 is provided with a buffer sealing ring 30 surrounding the vacuum adsorption port 28.

[0050] In one specific embodiment, the rotating support 08 is a disc-shaped motor suction cup, and the lifting support 05 is a lifting suction cup, both of which have vacuum suction ports 28.

[0051] The buffer sealing ring 30 can be an O-ring made of fluororubber, which uses its excellent buffering effect to adapt to the slight deformation of the wafer 09. At the same time, the rotating carrier 08 can be made of PETP material and its end face is polished to a smoothness within R0.8. This treatment ensures that even if the wafer 09 is slightly lifted by the lifting mechanism during centering movement, the surface of the rotating carrier 08 can maintain excellent smoothness, without jamming due to excessive friction or vacuum drop, thus ensuring the smoothness and positional accuracy of the centering movement process.

[0052] Preferably, the exposure chamber 01 has a feed port 31 for the wafer 09 to pass through on one side wall near the lifting mechanism. It also includes a sealing cylinder 32 disposed on the inner side wall of the exposure chamber 01. The output end of the sealing cylinder 32 is connected to a sealing plate 33. The sealing cylinder 32 drives the sealing plate 33 to switch between an avoidance position and a shielding position. When in the shielding position, the sealing plate 33 seals and covers the feed port 31. The bottom surface of the exposure chamber 01 is also provided with an exhaust box 34. The exhaust box 34 is configured to connect to an external negative pressure system and discharge particles generated in the exposure chamber 01. Specifically, the exhaust box 34 is disposed near the translation module 06 and the rotation module 07.

[0053] To accommodate the circuitry, the exposure chamber 01 is equipped with storage structures such as cable carriers 35. As the moving sliders and cable carriers 35 move within the exposure chamber 01, particles are generated due to friction. The exhaust box 34 can directly discharge these particles to the plant processing end, ensuring the cleanliness required by the production environment and promoting production stability and efficiency. The sealing cylinder 32 and the sealing plate 33 work together to give the exposure chamber 01 a sealable feed port 31, preventing physical obstruction during feeding. After the wafer 09 is loaded, the feed port 31 is immediately sealed to ensure the airtightness of the process and avoid interference from the external environment.

[0054] Furthermore, an FFU (High-Efficiency Filter) can be installed at the top of the exposure chamber 01 to provide air intake. This, combined with the exhaust of the exhaust box 34, forms a downward-pressure airflow field, further constructing the internal micro-circulation clean control system required for the complete photolithography process.

[0055] Figure 6 A schematic diagram of the exposure unit structure according to a specific embodiment of this application is shown, such as... Figure 1-7As shown, the exposure unit 02 includes a mounting bracket 36 vertically disposed on the bottom surface of the exposure cavity 01. The mounting bracket 36 is provided with a vertically extending second lifting guide rail 37, and a second lifting slider 38 is slidably disposed on the second lifting guide rail 37. A second lifting motor 39 is provided at one end of the second lifting guide rail 37, and the output end of the second lifting motor 39 is connected to the second lifting slider 38. A horizontal adjustment seat 40 is connected to the second lifting slider 38, and the optical module 41 of the exposure unit 02 is mounted on the horizontal adjustment seat 40.

[0056] The second lifting guide rail 37 can adjust the vertical position of the optical module 41. The optical module 41 is installed on the second lifting guide rail 37 along with the horizontal adjustment seat 40. At the same time, the horizontal position of the optical module 41 can also be adjusted (the translation module 06 is the horizontal longitudinal displacement). During the initial debugging of the equipment, the exposure point of the optical module 41 can be adjusted according to the situation, and it is convenient for later maintenance.

[0057] Furthermore, in the above embodiments, each guide rail (translation guide rail 21, second lifting guide rail 37) has a limit sensor 42 on one / both sides at the limit of the slider's stroke. Simultaneously, a trigger 43 cooperating with the limit sensor 42 is provided on one / both sides of the slider. In the lifting drive module 04 of one embodiment, the limit sensor 42 is provided on both sides of the mounting plate 16, and the trigger 43 is provided on both sides of the lifting plate 13.

[0058] According to a second aspect of this application, an automatic edge-finding and alignment exposure method for wafers is proposed, employing the exposure apparatus described above. Figure 7 A flowchart of an automated wafer edge-finding and alignment exposure method according to an embodiment of this application is shown, as follows: Figure 1-7 As shown, the method includes: S1: The translation module 06 drives the rotation module 07 to move to the loading and unloading station near the lifting mechanism. The external robot places the wafer 09 to be exposed on the rotating support 08. The rotating support 08 uses negative pressure to adsorb and fix the wafer 09. S2: The rotating module 07 carries the wafer 09 to the edge finding station corresponding to the edge finding unit 03. The rotating module 07 drives the rotating support 08 to rotate the wafer 09. The edge finding unit 03 obtains the edge data of the wafer 09 and calculates the eccentricity of the actual center of the wafer 09 relative to the rotation center of the rotating support 08. S3: Rotating module 07 drives wafer 09 to rotate, so that the actual center, the rotation center of rotating support component 08, and the support center of lifting support component 05 are on the same straight line; S4: The rotating module 07 carries the edge area of ​​the wafer 09 to the adjustment position where the lifting mechanism is located. The lifting drive module 04 controls the lifting support 05 to rise and uses negative pressure to adsorb the edge area. It is determined whether the lifting support 05 has adsorbed the edge area according to the negative pressure threshold. After adsorption, the rotating support 08 releases the negative pressure adsorption on the wafer 09. The translation module 06 drives the rotating module 07 to perform linear displacement compensation according to the eccentricity, so that the rotation center coincides with the actual center of the circle. The rotating support 08 re-adsorbs the wafer 09, and the lifting support 05 releases the adsorption and resets. S5: Rotating module 07 carries wafer 09 and moves it toward exposure unit 02, so that the edge area is located in the exposure station covered by exposure unit 02, and performs single-angle / multi-angle exposure operation; S6: After exposure is completed, the rotating module 07 carries the wafer 09 to the loading and unloading station, the rotating support 08 releases the adsorption, and the external robot removes the wafer 09.

[0059] After wafer 09 is loaded, the rotating support component 08 applies negative pressure to attract wafer 09 and moves it to the edge-finding station to perform an edge-finding operation. It locates the NOTCH point and the actual center of wafer 09 (calculating the eccentricity). Then, the rotating support component 08 controls the rotation of wafer 09 until the actual center, the rotation center of the rotating support component 08, and the support center of the lifting support component 05 are aligned. At this point, the wafer 09 is moved until the edge area is above the lifting support component 05. The lifting support component 05 applies negative pressure to attract the edge area, thus supporting one side of the edge area of ​​wafer 09, and the rotating support component 08 can then be released. Negative pressure adsorption is used, and the rotating support 08 always supports the bottom surface of the wafer 09 without affecting the translation of the rotating support 08. At this time, the rotating support 08 is translated to a position concentric with the wafer 09 before the negative pressure adsorption is activated. This completes both the mechanical centering operation and the marking of the NOTCH point on the wafer 09. Finally, the wafer 09 is moved to the exposure station for single-angle or multi-angle exposure operations. No external robotic arm is required for secondary operation. The above processes can be completed in one go within the independent exposure chamber 01. This method has high integration and ensures the accuracy requirements of edge finding and centering of the wafer 09 and the stability of the process.

[0060] It is evident that those skilled in the art can make various modifications and alterations to the embodiments of the present invention without departing from the spirit and scope of the invention. In this way, the invention is also intended to cover such modifications and alterations if they fall within the scope of the claims and their equivalents. The word "comprising" does not exclude the presence of other elements or steps not listed in the claims. The simple fact that certain measures are described in mutually different dependent claims does not indicate that a combination of these measures cannot be used for profit. Any reference numerals in the claims should not be considered as limiting the scope.

Claims

1. A wafer automatic edge-finding and alignment multi-angle exposure apparatus, comprising an exposure cavity and an exposure unit and an edge-finding unit disposed within the exposure cavity, characterized in that, Also includes: The lifting mechanism is positioned opposite the exposure unit and spaced apart, and includes a lifting drive module and a lifting support component located at the top of the lifting drive module; The translation and rotation mechanism includes a translation module and a rotation module slidably disposed on the translation module. A rotation support member is rotatably connected to the top of the rotation module. The rotation axis of the rotation support member is parallel to the lifting axis of the lifting support member. The translation module drives the rotation module to perform horizontal linear movement between the exposure unit and the corresponding workstation of the lifting mechanism. The edge-finding unit is disposed between the exposure unit and the lifting mechanism and is offset to one side of the rotation module.

2. The exposure apparatus according to claim 1, characterized in that, The lifting drive module includes a lifting base, a first lifting motor, and a lifting plate. The lifting base is located on the inner bottom surface of the exposure cavity. The first lifting motor is located at the lower part of the lifting base, and its output end passes vertically upward through the lifting base and is connected to the bottom of the lifting plate. The lifting base has a vertical first lifting guide rail on the back of the lifting plate, and a first lifting slider is slidably mounted on the first lifting guide rail. The back of the lifting plate is connected to the first lifting slider.

3. The exposure apparatus according to claim 2, characterized in that, The lifting base has a vertical mounting plate formed on the back side of the lifting plate, the first lifting guide rail is disposed on the side of the mounting plate facing the lifting plate, and a distance measuring sensor is also provided on the top of the mounting plate.

4. The exposure apparatus according to claim 1, characterized in that, The diameter of the bearing surface of the rotating support is smaller than the diameter of the wafer to be exposed, so that the edge region of the wafer is suspended when it is adsorbed; wherein, when the edge region is located at the station of the lifting support, the horizontal projection of the bearing center of the lifting support is located within the edge region.

5. The exposure apparatus according to claim 1, characterized in that, The top surfaces of the lifting support and the rotating support each have at least one vacuum adsorption port for adsorbing wafers. The top surface of the rotating support is provided with several concentric pressure equalization grooves arranged around the vacuum adsorption port. Adjacent pressure equalization grooves are connected by openings. The top surface of the lifting support is embedded with a buffer sealing ring surrounding the vacuum adsorption port.

6. The exposure apparatus according to claim 1, characterized in that, The translation module includes a guide rail base, a translation guide rail, and a translation motor. The guide rail base is located on the inner bottom surface of the exposure cavity. The stroke of the translation guide rail is parallel to the horizontal line connecting the exposure unit and the lifting mechanism. The translation motor is located at one end of the translation guide rail, and the output end of the translation motor is connected to the translation slider of the translation guide rail. The bottom of the rotation module is connected to the translation slider.

7. The exposure apparatus according to claim 1, characterized in that, The rotating module includes a motor base, a rotary motor, and an origin detection component. The motor base is slidably mounted on the translation module. The rotary motor is mounted on the lower part of the motor base, and the output end of the rotary motor vertically upward passes through the top surface of the motor base and is connected to the center of the bottom surface of the rotating support. The origin detection component includes an origin sensor disposed on the edge of the top surface of the motor base and a sensing baffle disposed on the bottom surface of the rotating support. The sensing baffle cooperates with the origin sensor and is configured to determine the zero reference point of the rotating support.

8. The exposure apparatus according to claim 1, characterized in that, The exposure chamber has a feed port for wafers to pass through on one side wall near the lifting mechanism. It also includes a sealing cylinder disposed on the inner wall of the exposure chamber. The output end of the sealing cylinder is connected to a sealing plate. The sealing cylinder drives the sealing plate to switch between an avoidance position and a shielding position. When in the shielding position, the sealing plate seals and covers the feed port. The bottom surface of the exposure chamber is also provided with an exhaust box, which is configured to connect to an external negative pressure system and discharge particles generated in the exposure chamber.

9. The exposure apparatus according to claim 1, characterized in that, The exposure unit includes a mounting bracket vertically mounted on the bottom surface of the exposure cavity. The mounting bracket is provided with a vertically extending second lifting guide rail, and a second lifting slider is slidably mounted on the second lifting guide rail. A second lifting motor is provided at one end of the second lifting guide rail, and the output end of the second lifting motor is connected to the second lifting slider in a transmission connection. A horizontal adjustment seat is connected to the second lifting slider, and the optical module of the exposure unit is mounted on the horizontal adjustment seat.

10. A method for automatic edge-finding and alignment exposure of wafers, characterized in that, The exposure apparatus as described in any one of claims 1-9 comprises: S1: The translation module drives the rotation module to move to the loading / unloading station close to the lifting mechanism. The external robot places the wafer to be exposed on the rotating support, and the rotating support uses negative pressure to adsorb and fix the wafer. S2: The rotating module carries the wafer to the edge-finding station corresponding to the edge-finding unit. The rotating module drives the rotating support to rotate the wafer. The edge-finding unit obtains the edge data of the wafer and calculates the eccentricity of the actual center of the wafer relative to the rotation center of the rotating support. S3: The rotating module drives the wafer to rotate, so that the actual center of the wafer, the rotation center of the rotating support, and the support center of the lifting support are on the same straight line; S4: The rotating module carries the edge area of ​​the wafer to the adjustment position where the lifting mechanism is located. The lifting drive module controls the lifting support to rise and uses negative pressure to adsorb the edge area. It is determined whether the lifting support is adsorbed in place according to the negative pressure threshold. After adsorption, the rotating support releases the negative pressure adsorption on the wafer. The translation module drives the rotating module to perform linear displacement compensation according to the eccentricity, so that the rotation center coincides with the actual center of the circle. The rotating support re-adsorbs the wafer, and the lifting support releases the adsorption and resets. S5: The rotating module carries the wafer toward the exposure unit, so that the edge region is located in the exposure station covered by the exposure unit, and performs single-angle / multi-angle exposure operation; S6: After exposure is completed, the rotating module carries the wafer to the loading and unloading station, the rotating support is released from adsorption, and the external robot removes the wafer.

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