CN220585211U - Wafer edge-seeking positioning device - Google Patents

Abstract

The utility model discloses a wafer edge-finding positioning device, which belongs to the technical field of semiconductors and comprises a box body: the top of the box body is connected with a rotating assembly for rotating the wafer; the box body is connected with a movable detection assembly at the left end of the rotation assembly; the movable detection assembly comprises a horizontal driving assembly and a detection assembly, the horizontal driving assembly is arranged at the inner top of the box body, and the horizontal driving assembly is connected with the detection assembly; the box is connected with the centre of a circle locating component that is used for the wafer heart location at the rotation subassembly outer end, and centre of a circle locating component is connected with horizontal drive subassembly. Through the mode, the utility model realizes quick edge searching, so that the device is suitable for edge searching processing of wafers with different sizes.

Description

Wafer edge-seeking positioning device

Technical Field

The utility model relates to the technical field of semiconductors, in particular to a wafer edge-finding positioning device.

Background

Currently, for wafers of 8 inches (200 mm), 12 inches (300 mm) and even larger sizes, the semiconductor industry typically determines the position of the wafer through notches (notches) to achieve edge searching of the wafer, and edge searching typically employs an edge searching device.

For example, chinese patent CN219267627U discloses a wafer edge-seeking positioning device, which includes a purge apparatus; a wafer and a carrier for placing the wafer are arranged along the direction of a light source emitting and receiving path of the photoelectric correlation sensor; the purging device is arranged towards the photoelectric correlation sensor; the direction of the blowing device facing the photoelectric correlation type sensor forms a preset included angle with the direction of the light source transmitting and receiving path of the photoelectric correlation type sensor; the purging device is used for purging the photoelectric correlation type sensor so as to ensure that the surrounding environment of the photoelectric correlation type sensor is clean. According to the wafer edge-seeking and positioning device, the sweeping equipment is additionally arranged, so that the photoelectric opposite-type sensor is guaranteed to be clean in surrounding environment, particularly, the light source emission and receiving path environment is guaranteed to be clean, the receiving signal error caused by the existence of foreign matters (such as dust and fibers) in the wafer edge-seeking and positioning process of the photoelectric opposite-type sensor is avoided, the accurate edge-seeking and positioning of the wafer is guaranteed, and the wafer is positioned at the center of the workpiece carrier.

However, the above results have the following problems: the light source transmitting end 31 and the light source receiving end 32 are fixed in position and cannot be used for wafers with different sizes, and the structure cannot conduct circle center positioning on the wafers, and other equipment is required to conduct circle center positioning first, so that edge searching cannot be conducted rapidly.

Based on this, the present utility model designs a wafer edge-finding positioning device to solve the above-mentioned problems.

Disclosure of Invention

In view of the above drawbacks of the prior art, the present utility model provides a wafer edge-finding positioning device.

In order to achieve the above purpose, the utility model is realized by the following technical scheme:

a wafer edge locating device comprises a box body:

the top of the box body is connected with a rotating assembly for rotating the wafer;

the box body is connected with a movable detection assembly at the left end of the rotation assembly;

the movable detection assembly comprises a horizontal driving assembly and a detection assembly, the horizontal driving assembly is arranged at the inner top of the box body, and the horizontal driving assembly is connected with the detection assembly;

the box is connected with the centre of a circle locating component that is used for the wafer heart location at the rotation subassembly outer end, and centre of a circle locating component is connected with horizontal drive subassembly.

Still further, the rotating assembly includes a rotating cylinder, the sucking disc, the air guide sliding ring, the second ring gear, the mounting bracket, a motor, third ring gear and gas pocket, the box top is rotated through the bearing and is connected with a rotating cylinder, install the sucking disc in the rotating cylinder top mounting hole, and the sucking disc communicates with each other with the rotating cylinder, the air guide sliding ring is installed at the top in the box, and air guide sliding ring and rotating cylinder fixed connection, the rotating cylinder lower extreme is installed in the mounting hole of third ring gear, mounting bracket fixed mounting is at the top in the box, the motor is installed at the horizontal position of mounting bracket, the motor drive end runs through mounting bracket and second ring gear fixed connection, and second ring gear and third ring gear meshing are connected, the gas pocket has been seted up to rotating cylinder inner wall lower extreme, and the gas pocket communicates with each other with the air guide sliding ring end of giving vent to anger.

Still further, horizontal drive subassembly includes support frame, first guide rail assembly and cylinder, and first guide rail assembly and cylinder fixed mounting are in the bottom in the box, and cylinder drive fixedly connected with support frame, and the support frame bottom is connected with first guide rail assembly top.

Further, the top of the box body is provided with a first transverse groove, and the side wall of the support frame is in fit sliding connection with the inner wall of the first transverse groove.

Further, the detection assembly comprises a light receiver and a light emitter, wherein the light receiver is fixedly arranged at the inner top of the transverse part at the upper end of the support frame, the light emitter is fixedly arranged at the top of the transverse part at the middle end of the support frame, the bottom of the light receiver is opposite to the top of the light emitter, and the top of the light emitter is lower than the inner top of the box body.

Further, the guide rail of the first guide rail component is fixedly connected with the bottom in the box body, and the sliding block of the first guide rail component is fixedly connected with the bottom of the support frame.

Still further, centre of a circle locating component includes locating component and synchronous drive subassembly, and synchronous drive subassembly is connected with horizontal drive subassembly, and synchronous drive subassembly is connected with three same locating component of group, and locating component along equidistant setting in the rotation subassembly outside of circumference, with the adjacent locating component of detection subassembly with detect the subassembly dislocation set.

Still further, positioning component includes straight slide, pressure sensor, arc guide slot, second cross slot and second guide rail assembly, the box is rotating the section of thick bamboo outside along equidistant second cross slot of having seted up of circumference, laminating sliding connection has the straight slide in the second cross slot, the arc guide slot has been seted up to the bottom upper end in the straight slide, install pressure sensor in the mounting hole of straight slide upper end, and pressure sensor is located arc guide slot lower extreme, straight slide bottom is connected with second guide rail assembly, and second guide rail assembly fixed mounting is in the bottom in the box.

Still further, synchronous drive assembly includes fourth ring gear, fifth ring gear, the second rack, the third rack, the fourth rack, first ring gear, first rack and straight axle, the inner bottom of box passes through the bearing and rotates with the straight axle to be connected, straight axle from bottom to top fixedly connected with first ring gear, fourth ring gear and fifth ring gear, fourth ring gear and second rack meshing are connected, second rack and the straight slide lateral wall fixed connection of rear end, fifth ring gear and third rack meshing are connected, third rack and the straight slide lateral wall fixed connection of front end, first ring gear is connected with fourth rack and first rack along circumference meshing, and the straight slide lateral wall fixed connection in the centre of fourth rack and fourth rack, first rack and the right-hand member fixed connection of support frame.

Further, the central axis of the straight shaft coincides with the central axis of the rotary cylinder.

Advantageous effects

According to the utility model, the cylinder of the horizontal driving assembly of the movable detection assembly pushes the support frame to move, the support frame horizontally moves under the action of the first guide rail assembly, the support frame drives the light receiver and the light emitter of the detection assembly to move to the set positions, the rotating assembly drives the wafer to rotate, the outer edge of the rotating wafer rotates along the gap between the light receiver and the light emitter, and the gap position is determined through the optical signals between the light receiver and the light emitter, so that quick edge searching is realized, and the device is suitable for edge searching treatment of wafers with different sizes.

According to the size of a wafer, the cylinder of the horizontal driving assembly of the movable detection assembly pushes the support frame to move, the support frame moves horizontally under the action of the first guide rail assembly, the support frame drives the light collector and the light emitter of the detection assembly to move to a set position, the support frame drives the first rack of the synchronous driving assembly of the circle center positioning assembly when the support frame moves, the first rack drives the middle end of the first gear ring, the first gear ring drives the straight shaft to rotate, the first gear ring drives the fourth rack to move, the straight shaft drives the fourth gear ring and the fifth gear ring to synchronously rotate with the first gear ring, the fourth gear ring drives the third rack to move, the fifth gear ring drives the second rack to move, the second rack, the first rack, the third rack and the fourth rack synchronously move, the straight slide plate and the support frame synchronously move, the circle center positioning assembly moves to the set position along with the movable detection assembly, then the wafer is placed on the rotating cylinder, the wafer moves downwards under the guidance of the three groups of arc-shaped guide grooves when the wafer moves, the three groups of arc-shaped guide grooves conduct contact pressure detection, the three groups of pressure sensors detect the circle centers of the wafer, the wafer are positioned at the same detection values, the circle center of the three groups of pressure sensors rotate, the circle centers of the wafer are positioned at the circle centers of the wafer rotating cylinder, the circle centers are positioned at the positions of the circle center gaps, and the wafer centers are positioned at the wafer gaps, and the wafer rotation positions are required to be positioned, and the wafer center positions are rotated, and the wafer center positions and the wafer is positioned at the circle center positions, and the wafer center positions and the wafer circle center guide plate and the wafer.

After the circle center positioning assembly positions the circle center of the wafer, the external air pump pumps the rotating cylinder to negative pressure through the air guide slip ring and the air holes, then the sucker forms negative pressure, the sucker forms negative pressure to adsorb the wafer on the top of the rotating cylinder, then the motor drives the second gear ring to rotate, the second gear ring drives the third gear ring to rotate, the third gear ring drives the rotating cylinder to rotate, and the rotating cylinder drives the adsorbed wafer to rotate, so that the wafer can be conveniently driven to stably move.

Drawings

In order to more clearly illustrate the embodiments of the present utility model or the technical solutions in the prior art, the drawings used in the description of the embodiments or the prior art will be briefly described below. It is evident that the drawings in the following description are only some embodiments of the present utility model and that other drawings may be obtained from these drawings without inventive effort for a person of ordinary skill in the art.

FIG. 1 is a perspective view of a main structure of a wafer edge-finding positioning apparatus according to the present utility model;

FIG. 2 is a side view of a wafer edge-seeking positioning apparatus according to the present utility model;

FIG. 3 is a front view of a wafer edge-seeking positioning apparatus according to the present utility model;

FIG. 4 is a perspective view of a main structure of a wafer edge-seeking positioning apparatus according to the present utility model;

FIG. 5 is a cross-sectional view taken along the direction A-A of FIG. 2;

fig. 6 is a sectional view taken along the B-B direction of fig. 3.

Reference numerals in the drawings represent respectively:

1. case 2, mobile sensing assembly 21, support frame 22, light receiver 23, first transverse slot 24, first rail assembly 25, light emitter 26, cylinder 3, rotating assembly 31, rotating barrel 32, suction cup 33, air slip ring 34, second gear ring 35, mounting bracket 36, motor 37, third gear ring 38, air hole 4, center positioning assembly 41, straight slide 42, pressure sensor 43, arcuate guide slot 44, second transverse slot 45, fourth gear ring 46, fifth gear ring 47, second rail assembly 48, second rack 49, third rack 410, fourth rack 411, first gear ring 412, first rack 413, and straight axle.

Detailed Description

In order to make the objects, technical solutions and advantages of the embodiments of the present utility model more clear, the technical solutions of the embodiments of the present utility model will be clearly and completely described below with reference to the accompanying drawings in the embodiments of the present utility model. It will be apparent that the described embodiments are some, but not all, embodiments of the utility model. All other embodiments, which can be made by those skilled in the art based on the embodiments of the utility model without making any inventive effort, are intended to be within the scope of the utility model.

The utility model is further described below with reference to examples.

Example 1

Referring to fig. 1-6 of the specification, a wafer edge-seeking positioning device includes a case 1:

the top of the box body 1 is connected with a rotating assembly 3 for rotating the wafer;

the rotating assembly 3 comprises a rotating cylinder 31, a sucker 32, an air guide slip ring 33, a second gear ring 34, a mounting frame 35, a motor 36, a third gear ring 37 and an air hole 38, wherein the top of the box body 1 is rotationally connected with the rotating cylinder 31 through a bearing, the sucker 32 is arranged in a mounting hole at the top of the rotating cylinder 31, the sucker 32 is communicated with the rotating cylinder 31, the air guide slip ring 33 is arranged at the top of the box body 1, the air guide slip ring 33 is fixedly connected with the rotating cylinder 31, the lower end of the rotating cylinder 31 is arranged in a mounting hole of the third gear ring 37, the mounting frame 35 is fixedly arranged at the inner top of the box body 1, the motor 36 is arranged at the transverse position of the mounting frame 35, the driving end of the motor 36 penetrates through the mounting frame 35 and is fixedly connected with the second gear ring 34, the second gear ring 34 is meshed with the third gear ring 37, the air hole 38 is arranged at the lower end of the inner wall of the rotating cylinder 31, and the air hole 38 is communicated with the air outlet end of the air guide slip ring 33;

the outer ring of the air guide slip ring 33 is fixedly connected with the inner top of the box body 1, and the inner ring of the air guide slip ring 33 is fixedly connected with the outer wall of the rotating cylinder 31;

the wafer is placed on the top of a rotating cylinder 31 of a rotating assembly 3, after the circle center positioning assembly 4 positions the circle center of the wafer, an external air pump pumps the rotating cylinder 31 to negative pressure through an air guide slip ring 33 and an air hole 38, then a suction disc 32 forms negative pressure, the suction disc 32 forms negative pressure to adsorb the wafer on the top of the rotating cylinder 31, then a motor 36 drives a second gear ring 34 to rotate, the second gear ring 34 drives a third gear ring 37 to rotate, the third gear ring 37 drives the rotating cylinder 31 to rotate, and the rotating cylinder 31 drives the adsorbed wafer to rotate so as to facilitate driving the wafer to stably move;

the box body 1 is connected with a movable detection assembly 2 at the left end of a rotation assembly 3;

the movable detection assembly 2 comprises a horizontal driving assembly and a detection assembly, wherein the horizontal driving assembly is arranged at the inner top of the box body 1, and the horizontal driving assembly is connected with the detection assembly;

the horizontal driving assembly comprises a supporting frame 21, a first guide rail assembly 24 and an air cylinder 26, wherein the first guide rail assembly 24 and the air cylinder 26 are fixedly arranged at the inner bottom of the box body 1, the air cylinder 26 is fixedly connected with the supporting frame 21 in a driving manner, and the bottom of the supporting frame 21 is connected with the top of the first guide rail assembly 24;

the top of the box body 1 is provided with a first transverse groove 23, and the side wall of the supporting frame 21 is in fit sliding connection with the inner wall of the first transverse groove 23;

the detection assembly comprises a light receiver 22 and a light emitter 25, wherein the light receiver 22 is fixedly arranged at the inner top of the transverse part of the upper end of the support frame 21, the light emitter 25 is fixedly arranged at the top of the transverse part of the middle end of the support frame 21, the bottom of the light receiver 22 is opposite to the top of the light emitter 25, and the top of the light emitter 25 is lower than the inner top of the box body 1;

the guide rail of the first guide rail assembly 24 is fixedly connected with the bottom in the box body 1, and the sliding block of the first guide rail assembly 24 is fixedly connected with the bottom of the supporting frame 21;

according to the size of the wafer, the cylinder 26 of the horizontal driving assembly of the movable detection assembly 2 is started to push the support frame 21 to move, the support frame 21 horizontally moves under the action of the first guide rail assembly 24, the support frame 21 drives the light receiver 22 and the light emitter 25 of the detection assembly to move to a set position, the rotating assembly 3 drives the wafer to rotate, the outer edge of the rotating wafer rotates between the light receiver 22 and the light emitter 25, the notch position is determined through optical signals between the light receiver 22 and the light emitter 25, and quick edge searching is realized, so that the device is suitable for edge searching of wafers with different sizes;

the outer end of the rotating assembly 3 of the box body 1 is connected with a circle center positioning assembly 4 for positioning the wafer center, and the circle center positioning assembly 4 is connected with a horizontal driving assembly;

the circle center positioning assembly 4 comprises a positioning assembly and a synchronous driving assembly, the synchronous driving assembly is connected with the horizontal driving assembly, the synchronous driving assembly is connected with three groups of identical positioning assemblies, the positioning assemblies are arranged on the outer side of the rotating assembly 3 along the circumferential direction at equal intervals, and the positioning assemblies adjacent to the detecting assembly are arranged in a staggered manner with the detecting assembly;

the positioning assembly comprises a straight slide plate 41, a pressure sensor 42, an arc-shaped guide groove 43, a second transverse groove 44 and a second guide rail assembly 47, wherein the second transverse groove 44 is formed in the outer side of the rotary drum 31 at equal intervals along the circumferential direction, the straight slide plate 41 is connected in an adhering sliding manner in the second transverse groove 44, the arc-shaped guide groove 43 is formed in the upper end of the inner bottom of the straight slide plate 41, the pressure sensor 42 is arranged in a mounting hole in the upper end of the straight slide plate 41, the pressure sensor 42 is positioned at the lower end of the arc-shaped guide groove 43, the second guide rail assembly 47 is connected to the bottom of the straight slide plate 41, and the second guide rail assembly 47 is fixedly arranged at the inner bottom of the box 1;

the sensing end of the pressure sensor 42 is slightly higher than the top of the rotary drum 31;

the top of the straight slide plate 41 is fixedly connected with a slide block of a second guide rail assembly 47, and a guide rail of the second guide rail assembly 47 is fixedly connected with the inside of the box body 1;

the synchronous drive assembly comprises a fourth gear ring 45, a fifth gear ring 46, a second gear rack 48, a third gear rack 49, a fourth gear rack 410, a first gear ring 411, a first gear rack 412 and a straight shaft 413, wherein the inner bottom of the box 1 is rotationally connected with the straight shaft 413 through a bearing, the first gear ring 411, the fourth gear ring 45 and the fifth gear ring 46 are fixedly connected with the straight shaft 413 from bottom to top, the fourth gear ring 45 is meshed with the second gear rack 48, the second gear rack 48 is fixedly connected with the side wall of the rear end straight slide 41, the fifth gear rack 46 is meshed with the third gear rack 49, the third gear rack 49 is fixedly connected with the side wall of the front end straight slide 41, the first gear rack 411 is meshed with the fourth gear rack 410 and the first gear rack 412 along the circumferential direction, and the fourth gear rack 410 is fixedly connected with the side wall of the middle straight slide 41;

the central axis of the straight shaft 413 coincides with the central axis of the rotary drum 31;

the first rack 412 is fixedly connected with the right end of the supporting frame 21

The middle end straight slide plate 41 is arranged opposite to the support frame 21;

according to the size of the wafer, the cylinder 26 of the horizontal driving component of the movable detection component 2 pushes the support frame 21 to move, the support frame 21 horizontally moves under the action of the first guide rail component 24, the support frame 21 drives the light receiver 22 and the light emitter 25 of the detection component to move to a set position, the support frame 21 drives the first rack 412 of the synchronous driving component of the circle center positioning component 4 when the support frame 21 moves, the first rack 412 drives the middle end of the first gear ring 411, the first gear ring 411 drives the straight shaft 413 to rotate, the first gear ring 411 drives the fourth rack 410 to move, the straight shaft 413 drives the fourth gear ring 45 and the fifth gear ring 46 to synchronously rotate with the first gear ring 411, the fourth gear ring 45 drives the third rack 49 to move, the fifth gear ring 46 drives the second rack 48 to move, the second rack 48, the first rack 412, the third rack 49 and the fourth rack 410 to synchronously move, realize straight slide 41 and support frame 21 synchronous motion, the synchronous motion of circle center locating component 4 follow movable type detection component 2, straight slide 41 moves to the settlement position when the support frame 21 moves to the settlement position, then put the wafer on the rotary drum 31, three groups of arc guide grooves 43 guide down move when the wafer moves, three groups of pressure sensor 42 carry out contact pressure detection, the centre of a circle of wafer is located the centre of a circle department of rotary drum 31 when the three groups of pressure sensor 42 detected value are the same, the centre of a circle of wafer and the centre of a circle of rotary drum 31 dislocation when the detected value of three groups of pressure sensor 42 is different, and the breach of wafer is located a set of straight slide 41 department, it rotates certain angle to need to rotate the subassembly 3 to drive the wafer this moment, rotate the breach of wafer to straight slide 41 outside, the centre of a circle of wafer is located the centre of a circle department of rotary drum 31 this moment, realize the centre of a circle location of wafer.

The above embodiments are only for illustrating the technical solution of the present utility model, and are not limiting; although the utility model has been described in detail with reference to the foregoing embodiments, it will be understood by those of ordinary skill in the art that: the technical scheme described in the foregoing embodiments can be modified or some technical features thereof can be replaced by equivalents; such modifications and substitutions do not depart from the spirit and scope of the technical solutions of the embodiments of the present utility model.

Claims (10)

1. The utility model provides a wafer edge-seeking positioner, includes box (1), its characterized in that:

the top of the box body (1) is connected with a rotating assembly (3) for rotating the wafer;

the box body (1) is connected with a movable detection assembly (2) at the left end of the rotation assembly (3);

the movable detection assembly (2) comprises a horizontal driving assembly and a detection assembly, the horizontal driving assembly is arranged at the inner top of the box body (1), and the horizontal driving assembly is connected with the detection assembly;

the outer end of the rotating assembly (3) of the box body (1) is connected with a circle center positioning assembly (4) for positioning the wafer center, and the circle center positioning assembly (4) is connected with a horizontal driving assembly.

2. The wafer edge finding positioning device according to claim 1, wherein the rotating assembly (3) comprises a rotating cylinder (31), a suction cup (32), an air guide slip ring (33), a second gear ring (34), a mounting frame (35), a motor (36), a third gear ring (37) and an air hole (38), the rotating cylinder (31) is rotatably connected to the top of the box (1) through a bearing, the suction cup (32) is mounted in a mounting hole in the top of the rotating cylinder (31), the suction cup (32) is communicated with the rotating cylinder (31), the air guide slip ring (33) is mounted on the top of the box (1), the air guide slip ring (33) is fixedly connected with the rotating cylinder (31), the lower end of the rotating cylinder (31) is mounted in a mounting hole of the third gear ring (37), the mounting frame (35) is fixedly mounted on the inner top of the box (1), the motor (36) is mounted at a transverse position, the driving end of the motor (36) penetrates through the mounting frame (35) and is fixedly connected with the second gear ring (34), the second gear ring (34) is meshed with the third gear ring (37), the lower end of the rotating cylinder (31) is fixedly connected with the air guide slip ring (38), and the air guide slip ring (38) is opened.

3. The wafer edge finding positioning device according to claim 2, wherein the horizontal driving assembly comprises a supporting frame (21), a first guide rail assembly (24) and an air cylinder (26), the first guide rail assembly (24) and the air cylinder (26) are fixedly arranged at the inner bottom of the box body (1), the air cylinder (26) is fixedly connected with the supporting frame (21) in a driving mode, and the bottom of the supporting frame (21) is connected with the top of the first guide rail assembly (24).

4. A wafer edge-seeking positioning device according to claim 2 or 3, wherein the top of the box body (1) is provided with a first transverse groove (23), and the side wall of the supporting frame (21) is in fit sliding connection with the inner wall of the first transverse groove (23).

5. The wafer edge finding positioning device according to claim 4, wherein the detection assembly comprises a light collector (22) and a light emitter (25), the light collector (22) is fixedly arranged at the inner top of the transverse part at the upper end of the support frame (21), the light emitter (25) is fixedly arranged at the top of the transverse part at the middle end of the support frame (21), the bottom of the light collector (22) is opposite to the top of the light emitter (25), and the top of the light emitter (25) is lower than the inner top of the box body (1).

6. The wafer edge-seeking positioning device according to claim 5, wherein the guide rail of the first guide rail assembly (24) is fixedly connected with the bottom of the box body (1), and the slide block of the first guide rail assembly (24) is fixedly connected with the bottom of the supporting frame (21).

7. The wafer edge-finding positioning device according to claim 6, wherein the circle center positioning assembly (4) comprises a positioning assembly and a synchronous driving assembly, the synchronous driving assembly is connected with the horizontal driving assembly, the synchronous driving assembly is connected with three groups of identical positioning assemblies, the positioning assemblies are arranged outside the rotating assembly (3) at equal intervals along the circumferential direction, and the positioning assemblies adjacent to the detecting assembly are arranged in a staggered manner with the detecting assembly.

8. The wafer edge finding positioning device according to claim 7, wherein the positioning assembly comprises a straight slide plate (41), a pressure sensor (42), an arc-shaped guide groove (43), a second transverse groove (44) and a second guide rail assembly (47), the second transverse groove (44) is formed in the outer side of the rotating cylinder (31) at equal intervals along the circumferential direction, the straight slide plate (41) is connected in the second transverse groove (44) in a bonding sliding manner, the arc-shaped guide groove (43) is formed in the upper end of the inner bottom of the straight slide plate (41), the pressure sensor (42) is mounted in a mounting hole in the upper end of the straight slide plate (41), the pressure sensor (42) is located at the lower end of the arc-shaped guide groove (43), the second guide rail assembly (47) is connected to the bottom of the straight slide plate (41), and the second guide rail assembly (47) is fixedly mounted at the inner bottom of the box (1).

9. The wafer edge finding positioning device according to claim 8, wherein the synchronous driving assembly comprises a fourth gear ring (45), a fifth gear ring (46), a second gear rack (48), a third gear rack (49), a fourth gear rack (410), a first gear ring (411), a first gear rack (412) and a straight shaft (413), wherein the inner bottom of the box body (1) is rotationally connected with the straight shaft (413) through a bearing, the straight shaft (413) is fixedly connected with the first gear ring (411), the fourth gear ring (45) and the fifth gear ring (46) from bottom to top, the fourth gear ring (45) is in meshed connection with the second gear rack (48), the second gear rack (48) is in meshed connection with the side wall of a straight slide plate (41) at the rear end, the fifth gear rack (46) is in meshed connection with the third gear rack (49), the third gear rack (49) is in meshed connection with the side wall of a straight slide plate (41) at the front end, the first gear rack (410) is in meshed connection with the fourth gear rack (412) along the circumferential direction, the fourth gear rack (410) is in fixed connection with the side wall of a straight slide plate (41) at the middle, and the fourth gear rack (410) is fixedly connected with the right end of a rack (21).

10. The wafer edge locating device according to claim 9, wherein the central axis of the straight shaft (413) coincides with the central axis of the rotary drum (31).