Dynamic centering device for semiconductor wafer

Abstract

The invention discloses a dynamic centering device for a semiconductor wafer, and the device comprises a rotary bearing part which comprises a sucker part and a rotating shaft which are coaxially disposed, the upper surface of the sucker part is provided with a vacuum adsorption region, and the sucker part and the rotating shaft are internally provided with a through gas channel; the dynamic sealing assembly comprises a sealing cylinder, the axial center position of the sealing cylinder is provided with an air guide part, the inner side edge of the air guide part gradually expands and extends inwards to form a first sealing part and a second sealing part which are symmetrical to each other, and the first sealing part and the second sealing part are in radial interference contact with the outer wall of the rotating shaft in a free state to form dynamic sealing interfaces on the two sides; the driving alignment assembly is used for driving the suction cup part of the rotary bearing piece to be aligned with the wafer; the secondary sealing piece is used for secondarily sealing the air guide part; and the first sealing part, the second sealing part and the inner wall of the rotating shaft are enclosed to form an annular gas buffer cavity. By adopting the scheme, the adsorption stability of the wafer in the centering process is improved, the wafer is prevented from falling off, and the noise is reduced.

Description

Technical Field

[0001] The present invention relates to the technical field of semiconductor wafer conveying equipment, and particularly to a semiconductor wafer dynamic centering device. Background Art

[0002] In the field of semiconductor wafer manufacturing, the precise positioning of wafers is the core prerequisite for ensuring the yield of key processes such as lithography and etching. The outer edge of the wafer is usually designed with a V-shaped notch or a flat edge as a positioning mark to identify the wafer direction and the reference position of the chip array. When the robotic arm transfers the wafer from the cassette to the processing stage, it is necessary to rotate and align to make the center of the wafer coincide with the center of the stage and correct its azimuth angle to meet the micron-level positioning requirements of subsequent processes. This process places strict requirements on the motion accuracy, stability, and reliability of the equipment. Any minor position deviation or accidental displacement may cause a chain of process defects.

[0003] The current mainstream semiconductor wafer dynamic centering device adopts a rotating adsorption stage structure, which fixes the wafer by vacuum adsorption and drives it to rotate for alignment. However, the gas supply system of this structure has inherent defects: the vacuum air path needs to pass through the dynamic seal interface between the rotating shaft and the fixed component. The part of the existing semiconductor wafer dynamic centering device that supplies gas to the rotating adsorption stage has poor sealing performance, which leads to air leakage, affecting the adsorption force on the wafer. Under high-speed rotation conditions, the friction wear and thermal deformation of the seal structure will further damage the airtightness. More seriously, the traditional seal design often needs to increase the contact area to maintain the adsorption force, which results in a significant increase in rotational friction noise. Once the seal interface leaks, the vacuum degree will drop sharply, the adsorption force will disappear instantly, and the wafer will directly fall due to the loss of fixed support, causing irreversible wafer breakage and production line contamination. Therefore, it is necessary to provide a semiconductor wafer dynamic centering device to solve the above problems existing in the prior art. Summary of the Invention

[0004] The purpose of the present invention is to provide a semiconductor wafer dynamic centering device to improve the adsorption stability of the wafer during the centering process, avoid wafer dropping, and reduce noise.

[0005] To achieve the above purpose, the technical solution of the present invention is as follows: A semiconductor wafer dynamic centering device, comprising: A rotating support member, including a suction cup part and a rotating shaft arranged coaxially. The upper surface of the suction cup part is provided with a vacuum adsorption area for adsorbing the wafer. A through gas channel is opened in the suction cup part and the rotating shaft, and the gas channel is communicated with the vacuum adsorption area; A dynamic seal assembly is sleeved on the outer periphery of the rotating shaft and forms a relative rotating pair with the rotating shaft. The dynamic seal assembly includes a seal cylinder body. An air guiding part is provided at the axial center position of the seal cylinder body. First and second seal parts that are symmetric to each other are formed by gradually expanding and extending inward along the inner edge of the air guiding part. The first and second seal parts are in radial interference contact with the outer wall of the rotating shaft in a free state to form a bilateral dynamic seal interface. A driving alignment assembly is used to drive the suction cup part of the rotating support to be centered with the wafer, and includes a translation block. The seal cylinder body is fixedly connected to the translation block. A secondary seal is sleeved between the seal cylinder body and the dynamic seal assembly and is used to secondarily seal the air guiding part. Wherein, an annular gas buffer cavity is formed by enclosing the inner walls of the first seal part, the second seal part and the rotating shaft. After the dynamic seal assembly is assembled, the first seal part and the second seal part generate elastic deformation to maintain the dynamic seal interface with the rotating shaft.

[0006] The beneficial effects of a semiconductor wafer dynamic centering device provided by the present invention are as follows: The first seal part and the second seal part gradually expand and extend inward to form a sealed "horn" structure, with a small contact area with the rotating shaft, thereby resulting in low noise. The interference fit makes its sealing performance good, avoiding gas leakage in the dynamic seal and causing the wafer to fall off; the annular gas buffer cavity can buffer the gas flowing through here, making the negative pressure more stable and the adsorption more stable.

[0007] Further, the first seal part and the second seal part are sequentially arranged in a direction away from the suction cup part, and the contact pressure between the first seal part and the rotating shaft is greater than that of the second seal part.

[0008] By adopting the above technical solution, since the first seal part is adjacent to the vacuum adsorption area and bears a larger pressure difference, a higher contact pressure can be set to preferentially block the main leakage path and form a core seal barrier; while the second seal part is located downstream and forms a protection in a relatively low-pressure area with a lower contact pressure, which can relatively reduce the overall friction power consumption.

[0009] Further, a first annular protrusion, a second annular protrusion, a third annular protrusion and a fourth annular protrusion are sequentially arranged on the outer periphery of the seal cylinder body in a direction close to the suction cup part. A first annular groove is formed between the first annular protrusion and the second annular protrusion, a second annular groove is formed between the second annular protrusion and the third annular protrusion, and the second annular groove communicates with all the air guiding parts; a third annular groove is formed between the third annular protrusion and the fourth annular protrusion, and the secondary seal is arranged in the first annular groove and the third annular groove.

[0010] By adopting the above technical solution, the secondary seals in the first and third annular grooves form a static seal, and the layered seal structure can separate the dynamic seal and the static seal, reducing mutual interference. The secondary seal is integrated in the groove, further improving the sealing effect while saving installation space.

[0011] Further, the translation block is provided with a sinking groove, the dynamic seal assembly is arranged in the sinking groove, the secondary seal includes a first sealing ring and a second sealing ring, the first sealing ring is arranged between the first annular groove and the sinking groove; the second sealing ring is arranged between the third annular groove and the sinking groove.

[0012] Further, the air guiding part is uniformly provided with a plurality of through holes, and the radial aperture of the through holes gradually decreases.

[0013] By adopting the above technical solution, the radial aperture of the through hole gradually decreases, and the aperture of the airflow from the inlet to the outlet of the through hole gradually decreases, so as to reduce the airflow turbulence flowing through the through hole and improve the flow uniformity.

[0014] Further, the first sealing part and the second sealing part are integrally formed on the upper and lower sides of the air guiding part, and form a first gap and a second gap with the inner wall of the sealing cylinder respectively.

[0015] By adopting the above technical solution, the first seal and the second seal are integrally formed, reducing the risk of air leakage.

[0016] Further, the sealing cylinder body further includes a fixing part, the fixing part is formed by extending outward from the top of the outer periphery of the sealing cylinder body, and a fixing hole for fixing with the translation block is provided on the fixing part.

[0017] By adopting the above technical solution, it is convenient to install and fix the sealing cylinder body.

[0018] Further, the driving and aligning assembly includes: A housing, including a top plate, a strip-shaped window is provided in the middle of the top plate, the rotating support is arranged in the strip-shaped window, and lifting guide grooves are symmetrically provided on the top surface of the top plate along the X-axis direction; An optical detection module for detecting the position of the wafer located on the chuck part; A rotating part, fixedly connected to the bottom of the rotating shaft, for driving the rotating shaft to rotate; An X-axis translation assembly, connected to the rotating support for driving the rotating support to move along the length direction of the strip-shaped window; Lifting actuators, symmetrically distributed on both sides of the strip-shaped window, and the lifting actuator assembly forms a sliding fit with the lifting guide groove.

[0019] By adopting the above technical solution, the optical detection module is used to detect the position of the wafer on the suction cup part, and then the deviation from the center of the circle can be calculated. Then, the lifting actuator is used to lift the wafer and cancel the adsorption state of the wafer; after that, the rotating part is used to rotate, so that the rotating support part drives the wafer to rotate, making the vertical projection of the wafer center located within the strip window. Finally, the X-axis translation component is used to translate the center of the wafer, so as to align it with the rotating support part.

[0020] Further, the optical detection module includes opposed sensors vertically arranged along the Z-axis, and the opposed sensors emit laser beams along the Z-axis direction to form a vertical detection plane; When the wafer is placed on the suction cup part, the edge of the wafer blocks part of the laser beams, and at this time, the opposed sensors can non-contact detect the edge coordinate points of the wafer on the suction cup part.

[0021] By adopting the above technical solution, the edge coordinate points of the wafer can be detected.

[0022] Further, the X-axis translation part includes: A frame, installed inside the housing; A first motor, fixedly connected to the housing, and the output shaft of the first motor is connected with a coupling, and the coupling is in transmission connection with the first motor; A first slider, fixedly connected to the translation block, and a first slide rail along the X-axis direction is provided on the frame, and the first slider is slidably connected to the first slide rail; A first lead screw, extending along the X-axis direction and forming a coaxial transmission with the first motor through the coupling, and the first lead screw is in threaded cooperation with the translation block.

[0023] Further, the rotating part includes: A second motor, having an output end, and the rotating shaft has a shaft hole, and the output end extends into the shaft hole and is connected to the rotating shaft to drive the rotating shaft to rotate in the horizontal direction.

[0024] Further, the lifting actuator includes a third motor, a lifting guide rod, a slide table, a second lead screw, a Z-axis fixing frame, a bearing and a lifting transition block. The lifting guide rod is slidably connected in the lifting guide groove along the Z-axis direction, and the lifting guide rod is fixedly connected to the lifting transition block. The output shaft of the third motor is coaxially and fixedly connected to the second lead screw. The bearing is installed on the Z-axis fixing frame and is fixedly connected to the lead screw. The second lead screw is in threaded connection with the slide table. The Z-axis fixing frame is integrally formed, and a second slide rail is provided on the Z-axis fixing frame along the Z-axis direction, and the second slide rail is slidably connected to the slide table. Description of the Drawings

[0025] Figure 1 Schematic diagram of the overall structure of the semiconductor wafer dynamic centering device according to an embodiment of the present invention; Figure 2 Schematic diagram of the structure of the rotating support member according to an embodiment of the present invention; Figure 3 Cross-sectional view of the structure of the rotating support member according to an embodiment of the present invention; Figure 4 Schematic diagram of the structure of the dynamic seal assembly according to an embodiment of the present invention; Figure 5 Cross-sectional view of the dynamic seal assembly according to an embodiment of the present invention; Figure 6 Assembly cross-sectional view of the dynamic seal assembly according to an embodiment of the present invention; Figure 7 Schematic diagram of the translation block according to an embodiment of the present invention; Figure 8 Exploded view of the rotating support member according to an embodiment of the present invention; Figure 9 Schematic diagram of the structure of the rotating shaft according to an embodiment of the present invention; Figure 10 Schematic diagram of the internal structure of the semiconductor wafer dynamic centering device according to an embodiment of the present invention; Figure 11 Schematic diagram of the structure of the drive alignment assembly according to an embodiment of the present invention; Figure 12 Schematic diagram of the first perspective of the lifting actuator according to an embodiment of the present invention; Figure 13 Schematic diagram of the second perspective of the lifting actuator according to an embodiment of the present invention; Figure 14 Schematic diagram of the structure of the Z-axis fixing bracket according to an embodiment of the present invention.

[0026] Reference numerals: 100, rotating support member; 101, suction cup portion; 102, rotating shaft; 103, vacuum adsorption area; 104, central channel; 105, branch air duct; 106, air guiding and splitting groove; 200, dynamic seal assembly; 201, sealing cylinder body; 202, air guiding portion; 203, first sealing portion; 204, second sealing portion; 205, annular gas buffer cavity; 206, first annular protrusion; 207, second annular protrusion; 208, third annular protrusion; 209, fourth annular protrusion; 210, first annular groove; 211, second annular groove; 212, third annular groove; 213, through hole; 214, first gap; 215, second gap; 216, fixing portion; 217, fixing hole; 218, air hole; 219, joint; 300, translation block; 301, sinking groove; 400. Secondary seal; 401. First sealing ring; 402. Second sealing ring; 500. Housing; 501. Top plate; 502. Strip-shaped window; 503. Lifting guide groove; 504. Side cover; 505. Base; 600. Optical detection module; 601. Through-beam sensor; 602. Bracket; 700. Rotating part; 701. Second motor; 800. X-axis translation assembly; 801. Frame; 802. First motor; 803. Coupling; 804. First slider; 805. First slide rail; 806. First lead screw; 900. Lifting actuator; 901. Third motor; 902. Lifting guide rod; 903. Slide table; 904. Second lead screw; 905. Z-axis fixing bracket; 906. Bearing; 907. Lifting transition block; 908. Second slide rail; 909. Protrusion; 910. Protrusion groove. Detailed implementation mode

[0027] In order to make the objectives, technical solutions and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention will be clearly and completely described below. Apparently, the described embodiments are some but not all of the embodiments of the present invention. All other embodiments obtained by those of ordinary skill in the art based on the embodiments of the present invention without creative efforts shall fall within the protection scope of the present invention. Unless otherwise defined, the technical terms or scientific terms used herein shall have the ordinary meanings understood by those of ordinary skill in the art to which the present invention pertains. The words such as "including" used herein mean that the elements or objects appearing before this word cover the elements or objects listed after this word and their equivalents, without excluding other elements or objects.

[0028] The following will further describe in detail the specific implementation modes of the present invention with reference to the attached Figure 1 -attached Figure 14 drawings.

[0029] Refer to Figures 1 - 3 , in an embodiment of the present invention, a semiconductor wafer dynamic centering device includes a rotating support member 100, a dynamic seal assembly 200, a driving alignment assembly, and a secondary seal 400.

[0030] Refer to Figure 2, the rotating support member 100 includes a suction cup portion 101 and a rotating shaft 102 arranged coaxially. The upper surface of the suction cup portion 101 is provided with a vacuum adsorption area 103 for adsorbing a wafer. A through gas passage is formed in the suction cup portion 101 and the rotating shaft 102, and the gas passage is communicated with the vacuum adsorption area 103. In some specific embodiments of the present invention, the suction cup portion 101 is columnar, and a vacuum adsorption array concentric with the suction cup portion 101 and circumferentially uniformly distributed is arranged on the vacuum adsorption area 103 on its upper surface.

[0031] Referring to Figure 3 , the driving alignment assembly is used to drive the suction cup portion 101 of the rotating support member 100 to be centered with the wafer, and includes a translation block 300.

[0032] Referring to Figure 4 and Figure 5 , the dynamic sealing assembly 200 is cylindrical and sleeved on the outer periphery of the rotating shaft 102 and forms a relative rotating pair with the rotating shaft 102. The dynamic sealing assembly 200 includes a sealing cylinder body 201. A gas guiding portion 202 is provided at the axial center position of the sealing cylinder body 201. Symmetric first sealing portions 203 and second sealing portions 204 are formed by gradually expanding inward along the inner edge of the gas guiding portion 202. That is, it gradually tapers inward along the upper edge and the lower edge of the gas guiding portion.

[0033] The outer side of the sealing cylinder body 201 is fixedly connected to the translation block 300, and the inner side is used for dynamically sealing the gas guiding portion 202. The first sealing portions 203 and the second sealing portions 204 adopt a symmetric trumpet-shaped structure that expands inward, and form a two-side contact type dynamic seal with the rotating shaft 102. Compared with the traditional single-side planar seal, this design significantly reduces the frictional resistance by reducing the contact area, thereby effectively suppressing the noise generated by friction during rotation. In addition, the double-side seal forms a double sealing barrier. Even if a small leakage occurs on one side due to long-term wear, the other side can still maintain the basic sealing function, significantly improving the sealing reliability.

[0034] Referring to Figure 5 and Figure 6, the first sealing portion 203 and the second sealing portion 204 are in radial interference contact with the outer wall of the rotating shaft 102 in the free state to form a bilateral dynamic sealing interface. An annular gas buffer cavity 205 is formed by enclosing the inner walls of the first sealing portion 203, the second sealing portion 204 and the rotating shaft 102; after the dynamic sealing assembly 200 is assembled, the first sealing portion 203 and the second sealing portion 204 generate elastic deformation to maintain the dynamic sealing interface with the rotating shaft 102. In addition, due to the elastic first sealing portion 203 and the second sealing portion 204 being in radial interference contact with the outer wall of the rotating shaft 102 in the free state, initial sealing is achieved through elastic pre-tightening force, avoiding leakage caused by assembly gaps and preventing wafer dropping due to gas leakage in dynamic sealing. After the dynamic sealing assembly 200 is assembled, the elastic deformation of the sealing horn can dynamically compensate for the small radial displacement of the rotating shaft 102 caused by thermal expansion or mechanical vibration, ensuring the stability of the sealing interface under high-speed rotation conditions.

[0035] The annular gas buffer cavity 205 formed by enclosing the rotating shaft 102 with the bilateral first sealing portion 203 and the second sealing portion 204 reduces the sudden change in air flow velocity at the dynamic sealing location by expanding the gas flow cross-sectional area, alleviating the problem of negative pressure instability caused by pressure fluctuations during the vacuum adsorption process. The presence of the annular gas buffer cavity 205 can absorb pressure disturbances caused by the instantaneous vibration of the rotating shaft 102 or minute leakage at the sealing interface, preventing sudden changes in adsorption force caused by a sudden drop in vacuum degree.

[0036] Refer to Figure 6 , the secondary seal 400 is sleeved between the sealing cylinder 201 and the dynamic sealing assembly 200 for secondary sealing of the air guiding portion 202. The dynamic sealing assembly 200 undertakes the main sealing function and realizes dynamic interface sealing through bilateral horn-shaped sealing; the secondary seal 400 forms a static seal between the sealing cylinder 201 and the external components, preventing gas from leaking from the non-rotating interface, that is, the side facing the translation block 300. The two-stage sealing system forms a depth protection. Even if there is a small amount of leakage at the main sealing interface due to extreme working conditions, the secondary seal can still provide supplementary sealing guarantee, further reducing the overall leakage risk.

[0037] The first sealing portion 203 and the second sealing portion 204 are arranged in sequence along the direction away from the suction cup portion 101, and the contact pressure between the first sealing portion 203 and the rotating shaft 102 is greater than that of the second sealing portion 204. Since the first sealing portion 203 is adjacent to the vacuum adsorption area 103 and bears a larger pressure difference, a higher contact pressure is set to preferentially block the main leakage path and form a core sealing barrier; while the second sealing portion 204 is located downstream and forms a protection with a lower contact pressure in the relatively low-pressure area, which can relatively reduce the overall friction power consumption. In some specific embodiments of the present invention, the contact pressures between the first sealing portion 203 and the second sealing portion 204 and the rotating shaft 102 are 0.3 - 0.5 MPa and 0.2 - 0.4 MPa respectively.

[0038] Referring to Figure 5 and Figure 6 In some embodiments of the present invention, along the outer periphery of the sealing cylinder body 201 in the direction close to the suction cup portion 101, that is, from bottom to top, a first annular protrusion 206, a second annular protrusion 207, a third annular protrusion 208 and a fourth annular protrusion 209 are sequentially arranged. A first annular groove 210 is formed between the first annular protrusion 206 and the second annular protrusion 207, a second annular groove 211 is formed between the second annular protrusion 207 and the third annular protrusion 208, and the second annular groove 211 communicates with all the air guiding portions 202; a third annular groove 212 is formed between the third annular protrusion 208 and the fourth annular protrusion 209, and the secondary seal 400 is arranged in the first annular groove 210 and the third annular groove 212. The secondary seals 400 in the first and third annular grooves 212 form a static seal. The layered seal structure may separate the dynamic seal and the static seal, reducing mutual interference. The secondary seals are integrated in the grooves, further improving the sealing effect while saving the installation space. Among them, the first annular protrusion 206 is located at the bottom of the sealing cylinder body 201 and has a greater thickness than the second, third and fourth annular protrusions. The thickening design of the first annular protrusion 206 is to prevent assembly warping and improve the structural stability.

[0039] Referring to Figure 7 In some embodiments of the present invention, the translation block 300 is provided with a sunken groove 301, and the dynamic seal assembly 200 is arranged in the sunken groove 301. The sealing cylinder body 201 abuts against the inner wall of the sunken groove 301. The secondary seal 400 includes a first sealing ring 401 and a second sealing ring 402. The first sealing ring 401 is arranged between the first annular groove 210 and the sunken groove 301; the second sealing ring 402 is arranged between the third annular groove 212 and the sunken groove 301.

[0040] Referring to Figure 5 and Figure 6 In some embodiments of the present invention, the air guiding portion 202 is uniformly provided with a plurality of through holes 213, and the radial aperture of the through holes 213 gradually decreases. The radial aperture of the through holes 213 gradually decreases, and the aperture of the air flow from the inlet to the outlet of the through holes 213 gradually decreases, so as to be able to reduce the air flow turbulence flowing through the through holes 213 and improve the flow uniformity. Among them, the diameter of the air inlet of the through hole 213 is 1.5-2 mm, and the diameter of the air outlet of the through hole is 1.0-1.2 mm. The gas in the annular gas buffer cavity 205 enters the second annular groove 211 through the through holes 213 on the circumference of the air guiding portion 202, and the second annular groove 211 then enters the vacuum generator through the air holes 218 and the joint 219.

[0041] In some embodiments of the present invention, the first sealing portion 203 and the second sealing portion 204 are integrally formed on the upper and lower sides of the air guiding portion 202, and respectively form a first gap 214 and a second gap 215 with the inner wall of the sealing cylinder 201. The formation of the first gap 214 and the second gap 215 can, on the one hand, reduce the weight of the first sealing portion 203 and the second sealing portion 204, and on the other hand, provide a space for the elastic deformation of the first sealing portion 203 and the second sealing portion 204. The integrally formed design of the first sealing member and the second sealing member reduces the risk of air leakage.

[0042] Referring to Figure 6 , in some embodiments of the present invention, the sealing cylinder 201 further includes a fixing portion 216. The fixing portion 216 is formed by extending outward from the top of the outer periphery of the sealing cylinder 201. A fixing hole 217 for fixing with the translation block 300 is provided on the fixing portion 216, thereby facilitating the installation and fixation of the sealing cylinder 201.

[0043] Referring to Figure 8 and Figure 9 , in some specific embodiments, the gas passage includes a central air passage located in the suction cup portion 101 and a plurality of branch air passages 105 located inside the rotating shaft 102. The plurality of branch air passages 105 are opened along the height direction, and the branch air passages 105 are circumferentially distributed inside the rotating shaft 102. A gas guiding and splitting groove 106 is provided at the bottom of the central air passage. The branch air passages 105 are communicated with the central air passage through the gas guiding and splitting groove 106. The design of the central air passage and the multi-branch air passages 105 solves the problems of uneven gas distribution and response hysteresis in the traditional single air passage system, and can significantly improve the process stability and reliability of precision manufacturing equipment.

[0044] Referring to Figure 1 and Figure 10 , in some embodiments of the present invention, the driving and aligning assembly includes a housing 500, an optical detection module 600, a rotating member 700, an X-axis translation assembly 800, and a lifting actuator 900.

[0045] Referring to Figure 10 and Figure 11, in some embodiments of the present invention, the housing 500 includes a top plate 501, a base 505, and a side cover 504, which enclose to form a cavity. A strip-shaped window 502 is opened in the middle of the top plate 501. The rotary support member 100 is arranged in the strip-shaped window 502. Lifting guide grooves 503 are symmetrically opened on the top surface of the top plate 501 along the X-axis direction; an optical detection module 600, which is arranged on the top plate 501 for detecting the position of the wafer located on the suction cup portion 101; a rotating member 700, which is fixedly connected to the bottom of the rotating shaft 102 for driving the rotating shaft 102 to rotate; an X-axis translation assembly 800, which is connected to the rotary support member 100 for driving the rotary support member 100 to move along the length direction of the strip-shaped window 502; lifting actuators 900, which are symmetrically distributed on both sides of the strip-shaped window 502, and the lifting actuator assembly forms a sliding fit with the lifting guide grooves 503. The position of the wafer located on the suction cup portion 101 is detected by the optical detection module 600, and then the deviation from the center of the circle can be calculated. The lifting actuator 900 can lift the wafer to cancel the adsorption state of the wafer; the rotating member 700 rotates to drive the rotary support member 100 to drive the wafer to rotate, so that the vertical projection of the center of the wafer is located within the strip-shaped window 502; the X-axis translation assembly 800 is used to translate the center of the rotary support member 100 to achieve the centering of the wafer and the rotary support member 100.

[0046] Refer to Figure 1 , in some embodiments of the present invention, the optical detection module 600 includes opposed sensors 601 arranged vertically along the Z-axis. The opposed sensors 601 are installed on the top plate 501 through a bracket 602. The opposed sensors 601 emit laser beams along the Z-axis direction to form a vertical detection plane; the opposed sensors 601 include an upper positioning sensor and a lower positioning sensor, and the upper positioning sensor and the lower positioning sensor are respectively installed at the upper and lower ends of the bracket 602. A sensor outer cover is provided on the outer periphery of the opposed sensor 601 located at the upper end. When the wafer is placed on the suction cup portion 101, the edge of the wafer blocks part of the laser beam. At this time, the opposed sensors 601 can detect the edge coordinate points of the wafer on the suction cup portion 101 in a non-contact manner.

[0047] Refer to Figure 10 and Figure 11, in some embodiments of the present invention, the X-axis translation member includes: a frame 801 installed inside the housing 500; a first motor 802 fixedly connected to the housing 500, the output shaft of the first motor 802 is connected with a coupling 803, and the coupling 803 is in transmission connection with the first motor 802; a first slider 804 fixedly connected to the translation block 300, a first slide rail 805 along the X-axis direction is provided on the frame 801, and the first slider 804 is slidably connected to the first slide rail 805; a first lead screw 806 extending along the X-axis direction and forming a coaxial transmission with the first motor 802 through the coupling 803, and the first lead screw 806 is in threaded cooperation with the translation block 300. Specifically, the first motor 802 drives the first lead screw 806 to rotate through the coupling 803. A lead screw nut is embedded inside the translation block 300, and under the action of being threadedly connected to the first lead screw 806, the lead screw nut drives the translation block 300 to move along the X-axis direction, and the translation block 300 drives the first slider 804 to slide along the first slide rail 805, thereby realizing the X-axis movement of the rotary support member 100 located on the translation block 300.

[0048] Refer to Figure 10 , in some embodiments of the present invention, the rotating member 700 includes: a second motor 701 having an output end, the rotating shaft 102 has a shaft hole, and the output end extends into the shaft hole and is connected to the rotating shaft 102 for driving the rotating shaft 102 to rotate in the horizontal direction.

[0049] Refer to Figures 11 - 13 , in some embodiments of the present invention, the lifting actuator 900 includes a third motor 901, a lifting guide rod 902, a slide table 903, a second lead screw 904, a Z-axis fixing frame 905, a bearing 906, and a lifting transition block 907. The lifting guide rod 902 is slidably connected in the lifting guide groove 503 along the Z-axis direction, the lifting guide rod 902 is fixedly connected to the lifting transition block 907, the output shaft of the third motor 901 is coaxially and fixedly connected to the second lead screw 904, the bearing 906 is installed on the Z-axis fixing frame 905 and is fixedly connected to the lead screw, the second lead screw 904 is in threaded connection with the slide table 903, the Z-axis fixing frame 905 is integrally formed, a second slide rail 908 is provided on the Z-axis fixing frame 905 along the Z-axis direction, and the second slide rail 908 is slidably connected to the slide table 903. A hole for accommodating a lead screw nut is provided on the Z-axis fixing frame 905. The output end of the third motor 901 drives the second lead screw 904 to rotate through the coupling 803. The second lead screw 904 drives the lead screw nut on the Z-axis fixing frame 905 to drive the slide table 903 to lift along the Z-axis direction, and the slide table 903 slides along the slide rail; the slide table 903 drives the lifting guide rod 902 to rise or fall through the lifting transition block 907, thereby realizing the lifting, supporting, and separating of the wafer.

[0050] Refer to Figure 14, in some specific embodiments, the Z-axis fixing bracket 905 is provided with a bearing 906 installation area for installing the bearing 906. It is provided with a protruding groove 910 along the middle, and the sliding table 903 has a protruding portion 909, and the protruding portion 909 is arranged in the protruding groove 910, further optimizing the installation space and making the device more integrated.

[0051] Specifically, the wafer centering principle: First, perform optical positioning scanning. The upper opposed sensor 601 and the lower opposed sensor 601 emit laser beams along the Z-axis direction to form a vertical detection plane. When the wafer is placed on the chuck portion 101, its edge will block part of the laser beam, and the wafer edge coordinate points are obtained through non-contact edge detection. Based on the geometric center fitting algorithm, the plane offset (Δx, Δy) between the wafer center and the stage center and the rotation deviation angle (θ) around the Z-axis are calculated. Then, enter the dynamic adjustment stage. In the first step, perform the composite rotational movement of the rotating support 100 to eliminate the circumferential angular deviation (θ) of the wafer. In the second step, perform lifting and separating. The lifting actuators 900 on both sides lift the lifting guide rods 902 synchronously through precision lead screws to lift the wafer and form a gap with the chuck portion 101. The two are non-contact adjustments to avoid friction damage in subsequent adjustments. In the third step, the first lead screw 806 rotates to drive the rotating shaft 102 to move along the X-axis, and the rotating shaft 102 drives the rotating support 100 to move along the X-axis to compensate for the lateral offset (Δx). The compensation for the Y-axis deviation (Δy) needs to be achieved through the coordinated control of the rotation angle θ and the X-axis translation. The Y-axis deviation is converted by rotating the rotating support to deflect the wafer coordinate system by an angle θ relative to the coordinate system of the semiconductor wafer dynamic centering device, and the Y-axis deviation Δy is converted into a compensable component along the X-axis. Specifically, the rotating second motor 701 drives the rotating support 100 to drive the wafer to rotate around the Z-axis so that the center of the wafer is located within the bar-shaped window 502.

[0052] Specific centering process: First, load the wafer, then perform vacuum adsorption and fixation of the wafer, then perform optical scanning, then calculate Δx / Δy / θ, then rotate the rotating support 100 to obtain relative angle compensation, then perform lifting and separating of the wafer, then perform translation of the rotating support 100 to achieve center offset compensation, then lower the lifting guide rod 902, and adsorb the wafer to reset, and finally perform secondary verification.

[0053] Although the embodiments of the present invention have been described in detail above, it is obvious to those skilled in the art that various modifications and changes can be made to these embodiments. However, it should be understood that such modifications and changes are all within the scope and spirit of the present invention described in the claims. Moreover, the present invention described herein can have other embodiments and can be implemented or realized in various ways.

Claims

1. A semiconductor wafer dynamic centering device, characterized in that: include: The rotating support member (100) comprises a coaxially arranged suction cup portion (101) and a rotating shaft (102); a vacuum adsorption area (103) for adsorbing wafers is provided on the upper surface of the suction cup portion (101); a gas passage is provided in the suction cup portion (101) and the rotating shaft (102); and the gas passage is in communication with the vacuum adsorption area (103); A dynamic seal assembly (200) is sleeved on the outer circumference of the rotating shaft (102) and forms a relative rotation pair with the rotating shaft (102), the dynamic seal assembly (200) comprising a sealing cylinder (201), the sealing cylinder (201) having an air guide portion (202) at its axial center, and gradually extending inward along the inner edge of the air guide portion (202) to form a mutually symmetrical first seal portion (203) and a second seal portion (204), the first seal portion (203) and the second seal portion (204) being in radial interference contact with the outer wall of the rotating shaft (102) in a free state to form a double-sided dynamic sealing interface; A driving alignment assembly, used for driving the suction cup portion (101) of the rotating support member (100) to align with the wafer, comprising a translation block (300), the sealing cylinder (201) being fixedly connected to the translation block (300); A secondary sealing member (400) is sleeved between the sealing cylinder (201) and the dynamic sealing assembly (200) and is used for secondary sealing the air guide portion (202); The first sealing portion (203), the second sealing portion (204) and the inner wall of the rotating shaft (102) enclose an annular gas buffer chamber (205); after the dynamic sealing assembly (200) is assembled, the first sealing portion (203) and the second sealing portion (204) generate elastic deformation to maintain a dynamic sealing interface with the rotating shaft (102).

2. A semiconductor wafer dynamic centering device according to claim 1, characterized in that: The first sealing portion (203) and the second sealing portion (204) are arranged in sequence along a direction away from the suction cup portion (101), and the contact pressure between the first sealing portion (203) and the rotating shaft (102) is greater than that of the second sealing portion (204).

3. A semiconductor wafer dynamic centering device according to claim 1, characterized in that: The outer circumference of the sealing cylinder (201) is provided with a first annular protrusion (206), a second annular protrusion (207), a third annular protrusion (208) and a fourth annular protrusion (209) in sequence along a direction close to the suction cup portion (101); a first annular groove (210) is formed between the first annular protrusion (206) and the second annular protrusion (207); a second annular groove (211) is formed between the second annular protrusion (207) and the third annular protrusion (208); the second annular groove (211) is connected to all the air guide portions (202); a third annular groove (212) is formed between the third annular protrusion (208) and the fourth annular protrusion (209); the secondary sealing component (400) is arranged in the first annular groove (210) and the third annular groove (212).

4. A semiconductor wafer dynamic centering device according to claim 3, characterized in that: The translation block (300) is provided with a sinking groove (301), the dynamic sealing assembly (200) is arranged in the sinking groove (301), and the secondary sealing component (400) comprises a first sealing ring (401) and a second sealing ring (402), wherein the first sealing ring (401) is arranged between the first annular groove (210) and the sinking groove (301); and the second sealing ring (402) is arranged between the third annular groove (212) and the sinking groove (301).

5. The semiconductor wafer dynamic centering device according to claim 1, characterized in that: The air guide portion (202) is evenly provided with a plurality of through holes (213), and the diameters of the through holes (213) gradually decrease along the radial direction.

6. A semiconductor wafer dynamic centering device according to claim 1, characterized in that: The first sealing portion (203) and the second sealing portion (204) are integrally formed with the upper and lower sides of the air guide portion (202), and respectively form a first gap (214) and a second gap (215) with the inner wall of the sealing cylinder (201).

7. A semiconductor wafer dynamic centering device according to claim 1, characterized in that: The sealing cylinder (201) further comprises a fixing portion (216), wherein the fixing portion (216) is formed by extending outward from the top of the outer periphery of the sealing cylinder (201), and a fixing hole (217) for fixing to the translation block (300) is provided on the fixing portion (216).

8. The semiconductor wafer dynamic centering device according to claim 1, characterized in that: The drive alignment assembly comprises: The housing (500) comprises a top plate (501), a strip-shaped window (502) is provided in the middle of the top plate (501), the rotation support member (100) is arranged in the strip-shaped window (502), and a lifting guide groove (503) is symmetrically provided on the top surface of the top plate (501) along the X-axis direction; An optical detection module (600) for detecting the position of a wafer located on the suction cup portion (101); A rotating member (700) is fixedly connected to the bottom of the rotating shaft (102) and is used to drive the rotating shaft (102) to rotate; An X-axis translation assembly (800) connected to the rotating support member (100) and used to drive the rotating support member (100) to move along the length direction of the strip-shaped window (502); The lifting actuators (900) are symmetrically distributed on both sides of the strip-shaped window (502), and the lifting actuator components form a sliding fit with the lifting guide groove (503).

9. A semiconductor wafer dynamic centering device according to claim 8, characterized in that: The optical detection module (600) comprises a beam sensor (601) arranged vertically along the Z axis, wherein the beam sensor (601) emits a laser beam along the Z axis direction and forms a vertical detection plane; When a wafer is placed on the suction cup portion (101), the edge of the wafer blocks part of the laser beam, and at this time the incident sensor (601) can detect the coordinate point of the wafer edge on the suction cup portion (101) in a non-contact manner.

10. The semiconductor wafer dynamic centering device according to claim 8, characterized in that: The X-axis translation member comprises: A frame (801) is installed inside the housing (500); A first motor (802) is fixedly connected to the housing (500), an output shaft of the first motor (802) being connected to a coupling (803), and the coupling (803) is drivingly connected to the first motor (802); A first sliding block (804) is fixedly connected to the translation block (300); a first sliding rail (805) along the X-axis direction is provided on the frame (801); and the first sliding block (804) is slidably connected to the first sliding rail (805); The first screw rod (806) extends along the X-axis direction and forms a coaxial transmission with the first motor (802) through the coupling (803), and the first screw rod (806) is threadedly matched with the translation block (300).

11. A semiconductor wafer dynamic centering device according to claim 10, characterized in that: The rotating member (700) comprises: The second motor (701) has an output end, the rotating shaft (102) has a shaft hole, and the output end extends into the shaft hole to be connected to the rotating shaft (102) for driving the rotating shaft (102) to rotate in a horizontal direction.

12. A semiconductor wafer dynamic centering device according to claim 11, characterized in that: The lifting actuator (900) comprises a third motor (901), a lifting guide rod (902), a slide (903), a second screw rod (904), a Z-axis fixed frame (905), a bearing (906) and a lifting transition block (907); the lifting guide rod (902) is slidably connected in the lifting guide groove (503) along the Z-axis direction; the lifting guide rod (902) is fixedly connected to the lifting transition block (907); the output shaft of the third motor (901) is coaxially fixedly connected to the second screw rod (904); the bearing (906) is mounted on the Z-axis fixed frame (905) and fixedly connected to the screw rod; the second screw rod (904) is threadedly connected to the slide (903); the Z-axis fixed frame (905) is integrally formed; the Z-axis fixed frame (905) is provided with a second slide rail (908) along the Z-axis direction; and the second slide rail (908) is slidably connected to the slide (903).

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