Wafer edge searching device and wafer edge searching method

Abstract

The invention provides a wafer edge searching device and a wafer edge searching method. The wafer edge searching device comprises a bearing table, an edge detection device and a base table. The bearing table is installed on the base table and comprises a rotatable objective table and a wafer tray installed on the top of the objective table, and a rotating shaft of the objective table passes through the center of the wafer tray in the vertical direction. The edge detection device comprises a signal transmitter, a signal receiver, a first support and a second support. The second support is arranged on the base station below the wafer tray, and the signal receiver is installed at the top end of the second support. The first bracket is arranged on the base station on the side edge of the wafer tray; and the signal transmitter is arranged at the top end of the first bracket. The height of at least one of the objective table, the first support and the second support is adjustable. According to the technical scheme, the relative position of the signal path and the wafer can be adjusted, so that the signal path can pass through the edge position of the wafer all the time, and edge searching of wafers of different sizes is achieved.

Description

Technical Field

[0001] The present application relates to the field of semiconductor processing, and in particular, to a wafer edge finding device and a wafer edge finding method. Background Art

[0002] Wafer edge finding is an important step in the semiconductor manufacturing process. This step is related to the precise detection and positioning of devices, patterns or edges on the wafer for subsequent processing or detection. The use of appropriate wafer edge finding technology is essential to ensure the precise alignment and processing of wafers during the production process. In the prior art, a common wafer edge finding device consists of a wafer carrier, an optical signal transmitting and receiving device, and an external controller. When in use, the optical signal transmitting device can emit infrared, laser and other optical signals. The controller can determine the specific position of the wafer edge based on the optical signal results collected by the optical signal receiving device, and stop the wafer carrier from rotating when the wafer rotates to a specified angle, thereby achieving wafer edge finding.

[0003] However, in the prior art, the direction of the optical signal generated by the optical signal transmitting device is usually perpendicular to the wafer surface, and the positions of the optical signal transmitting and receiving devices are fixed. Therefore, if the diameter of the target wafer to be edge-finded is too large or too small, the optical signal cannot cover the positioning position of the wafer edge (such as the V-groove) during the rotation of the wafer. As a result, the optical signal is always blocked by the wafer, or the optical signal can always reach the optical signal receiving device smoothly, so that the specific position of the wafer edge cannot be located, resulting in the failure of wafer edge-finding. In addition, the size of the wafer carrier under the prior art is usually not adjustable and can only be applied to wafers of a single size, which also reduces the versatility of the wafer edge-finding device. Summary of the invention

[0004] The purpose of the embodiments of the present application is to provide a wafer edge-finding device and a wafer edge-finding method, which can adjust the relative position of the signal path and the wafer so that the signal path can always pass through the edge position of the wafer, thereby realizing edge-finding for wafers of different sizes.

[0005] The present application provides a wafer edge-finding device, characterized in that it includes a carrier, an edge detection device and a base. The carrier is mounted on the base, and includes a rotatable stage and a wafer tray mounted on the top of the stage. The rotation axis of the stage is in the vertical direction and passes through the center of the wafer tray. The edge detection device includes a signal transmitter, a signal receiver, a first bracket and a second bracket. The second bracket is arranged on the base below the wafer tray, and the signal receiver is mounted on the top of the second bracket. The first bracket is arranged on the base at the side position of the wafer tray, and the signal transmitter is mounted on the top of the first bracket. The signal transmitter is higher than the wafer tray when in use. The signal receiver is opposite to the signal transmitter. At least one of the stage, the first bracket and the second bracket is configured as a height-adjustable structure.

[0006] In an implementable solution, center lines of the stage, the first bracket, and the second bracket are located in the same plane.

[0007] In an practicable solution, the horizontal distance between the center line of the stage and the center line of the first bracket is L 12 , the horizontal distance between the center line of the stage and the center line of the second bracket is L 13 The height of the stage is H1, the height of the first bracket is H2, and the height of the second bracket is H3. Among them, H2>H1>H3 and L 12 >L 13 .

[0008] In an implementable solution, the signal transmitter is installed on the top of the first bracket in an angle-adjustable manner, and the signal receiver is installed on the top of the second bracket in an angle-adjustable manner, and the angle adjustment plane of the signal transmitter is coplanar with the angle adjustment plane of the signal receiver.

[0009] In an practicable solution, the diameter of the wafer to be processed ranges from D±d, and the depth of the V-groove ranges from V h ±h, the horizontal distance between the center line of the first bracket and the center line of the second bracket is L 23 , then H1, H2, H3 and L 12 , L 23 The value of satisfies the following formula: Among them, V h -h>d;L 12 >1 / 2(D+d). M and N are safety factors, both of which are greater than 1. K is the adjustment factor, 0<K<1.

[0010] In an practicable solution, the wafer tray includes a tray rack, at least three retractable connecting rods fixedly arranged around the tray rack, and a support portion arranged at the free end of each connecting rod, the center of the tray rack is fixedly connected to the top of the stage, and the upper surface of the support portion is higher than the upper surface of the connecting rod and the tray rack. When in use, the circumference of the wafer rests on the upper surfaces of the multiple support portions.

[0011] In an practicable solution, each support portion is provided with a limiting portion at an edge away from the tray rack, the limiting portion being higher than the upper surface of the support portion. When the peripheral edge of the wafer is placed on the upper surfaces of the plurality of support portions, the edge of the wafer is located inside the limiting portion.

[0012] In an practicable solution, the limiting portion is provided with an arc-shaped fitting surface on one side close to the center of the tray rack. When in use, the fitting surface matches the shape of the edge of the wafer.

[0013] The present application also provides a wafer edge finding method, which uses a wafer edge finding device, which includes a carrier, an edge detection device and a base. The carrier is mounted on the base, and includes a rotatable and height-adjustable stage and a wafer tray mounted on the top of the stage, and the rotation axis of the stage is along the vertical direction and passes through the center of the wafer tray.

[0014] The edge detection device includes a signal transmitter, a signal receiver, a first bracket with adjustable height, and a second bracket with adjustable height. The second bracket is arranged on a base below the wafer tray, and the signal receiver is installed on the top of the second bracket in an adjustable angle form. The first bracket is arranged on a base at the side of the wafer tray, and the signal transmitter is installed on the top of the first bracket in an adjustable angle form, and the signal transmitter is higher than the wafer tray when in use. The signal receiver is opposite to the signal transmitter. The angle adjustment plane of the signal transmitter is coplanar with the angle adjustment plane of the signal receiver. The height of the stage is H1, the height of the first bracket is H2, and the height of the second bracket is H3. The wafer edge finding method includes:

[0015] S1. Place the wafer to be edge-finded on a wafer tray and make the V-groove on the edge of the wafer unobstructed, so that the rotation axis of the stage passes through the center of the wafer;

[0016] S2. Based on the diameter of the wafer and the depth of the V-groove at the edge of the wafer, adjust the height of at least one of H1, H2, and H3, and adjust the angles of the signal transmitter and the signal receiver so that the signal transmission path coincides with the signal reception path;

[0017] S3, the stage drives the wafer to rotate, and during the rotation process, it is determined whether the signal receiver receives the signal from the signal transmitter within a specific time period. If yes, it means that the signal path from the signal transmitter to the signal receiver passes through the V-groove, and the wafer edge finding is completed; if no, the rotation is stopped, and steps S2-S3 are repeated.

[0018] In an practicable solution, in step S2, the diameter range of the wafer to be processed is D±d, and the depth range of the V-groove is V h ±h, the horizontal distance between the center line of the stage and the center line of the first bracket is L 12 The horizontal distance between the center line of the first bracket and the center line of the second bracket is L 23 . H1, H2, H3 and L 12 , L 23 The value of satisfies the following formula: Among them, V h -h>d;L 12 >1 / 2(D+d). M and N are safety factors, both of which are greater than 1. K is the adjustment factor, 0<K<1.

[0019] Compared with the prior art, the beneficial effects of this application include at least:

[0020] The present application provides a wafer edge-finding device, in which the height of at least one of a stage, a first bracket, and a second bracket is adjustable. Therefore, the relative position of a signal path formed by a signal transmitter and a signal receiver and an edge of the wafer can be changed by adjusting the height of at least one of the stage, the first bracket, and the second bracket, thereby ensuring that for wafers of different sizes, the signal path can pass through the edge of the wafer so as to perform edge-finding on the wafer.

[0021] In a further solution, the angle between the signal transmitter and the signal receiver is adjustable. Therefore, not only the height of at least one of the stage, the first bracket, and the second bracket can be adjusted, but also the angle between the signal transmitter and the signal receiver can be adjusted, so as to more flexibly adjust the relative position of the signal path formed by the signal transmitter and the signal receiver and the edge of the wafer, thereby ensuring that for wafers of different sizes, the signal path can pass through the edge of the wafer to facilitate edge detection of the wafer. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] In order to more clearly illustrate the technical solutions of the embodiments of the present application, the drawings required for use in the embodiments will be briefly introduced below. It should be understood that the following drawings only show certain embodiments of the present application and therefore should not be regarded as limiting the scope. For ordinary technicians in this field, other related drawings can be obtained based on these drawings without paying creative work.

[0023] Figure 1 It is a side view of a wafer edge-finding device according to an embodiment of the present application;

[0024] Figure 2 for Figure 1 Schematic diagram of the size and working status of the wafer edge finding device;

[0025] Figure 3 is a top view of the carrier platform;

[0026] Figure 4 This is a top view of the wafer placed on the carrier;

[0027] Figure 5 It is a partial top view of the V-groove at the edge of the wafer, where the wafer size is D;

[0028] Figure 6 It is a partial top view of the V-groove at the edge of the wafer, where the wafer size is Dd;

[0029] Figure 7 It is a partial top view of the V-groove at the edge of the wafer, where the wafer size is D+d;

[0030] Figure 8 The figure is a flow chart of a wafer edge finding method according to an embodiment of the present application.

[0031] In the figure: 1. carrier platform; 2. edge detection device; 3. base; 4. controller; 5. wafer; 101. stage; 102. wafer tray; 121. tray rack; 122. connecting rod; 123. supporting part; 124. limiting part; 125. fitting surface; 201. signal transmitter; 202. signal receiver; 203. first bracket; 204. second bracket; 501. V-groove. DETAILED DESCRIPTION

[0032] In order to make the purpose, technical solution and advantages of the embodiments of the present application clearer, the technical solution in the embodiments of the present application will be clearly and completely described below in conjunction with the drawings in the embodiments of the present application. Obviously, the described embodiments are part of the embodiments of the present application, rather than all the embodiments. The components of the embodiments of the present application described and shown in the drawings here can be arranged and designed in various different configurations.

[0033] Therefore, the following detailed description of the embodiments of the present application provided in the accompanying drawings is not intended to limit the scope of the present application for which protection is sought, but merely represents selected embodiments of the present application. Based on the embodiments in the present application, all other embodiments obtained by ordinary technicians in the field without creative work are within the scope of protection of the present application.

[0034] like Figure 1 and Figure 2 As shown, the present application provides a wafer edge finding device, including a carrier 1, an edge detection device 2 and a base 3. The carrier 1 is mounted on the base 3, including a rotatable stage 101 and a wafer tray 102 mounted on the top of the stage 101, and the rotation axis of the stage 101 is along the vertical direction and passes through the center of the wafer tray 102. The edge detection device 2 includes a signal transmitter 201, a signal receiver 202, a first bracket 203 and a second bracket 204. The second bracket 204 is arranged on the base 3 below the wafer tray 102, and the signal receiver 202 is installed on the top of the second bracket 204. The first bracket 203 is arranged on the base 3 at the side of the wafer tray 102, and the signal transmitter 201 is installed on the top of the first bracket 203. The signal transmitter 201 is higher than the wafer tray 102 when in use. The signal receiver 202 is opposite to the signal transmitter 201. At least one of the stage 101 , the first bracket 203 and the second bracket 204 is configured as a height-adjustable structure.

[0035] like Figure 4 As shown, a positioning point is usually provided at the edge of the wafer, and a notch groove is generally provided as the positioning point. For example, in this case, it can be a V-shaped groove. When using the wafer edge-finding device, the wafer is first placed on the wafer tray 102 manually or by a robot, and then the carrier 1 is started so that the wafer tray 102 drives the wafer to rotate in the horizontal plane. The signal transmitter 201 and the signal receiver 202 are respectively located on both sides of the plane where the wafer is located, and their signal paths are at a certain angle to the horizontal plane and the vertical direction. The signal path emitted by the signal transmitter 201 passes through the edge of the wafer and is blocked by the edge of the wafer. When the V-shaped groove passes through the signal path, the signal can reach the signal receiver 202 through the V-shaped groove. Therefore, when the signal receiver 202 receives the signal, it indicates that the V-shaped groove is located at the intersection of the signal path and the plane where the wafer is located, thereby realizing the positioning of the V-shaped groove.

[0036] The signal transmitter 201 and the signal receiver 202 can use optical signals for signal transmission and reception, preferably using a signal type with good directivity and strong anti-interference ability, such as laser or infrared, and the specific signal type is not limited. In addition, the positions of the signal transmitter 201 and the signal receiver 202 can be interchanged, and the wafer edge finding function can also be realized.

[0037] In one embodiment, the center lines of the stage 101, the first bracket 203, and the second bracket 204 are located in the same plane. The horizontal distance between the center line of the stage 101 and the center line of the first bracket 203 is L 12 The horizontal distance between the center line of the stage 101 and the center line of the second bracket 204 is L 13 The horizontal distance between the center line of the first bracket 203 and the center line of the second bracket 204 is L 23 , the height of the stage 101 is H1, the height of the first bracket 203 is H2, and the height of the second bracket 204 is H3. Wherein, H2>H1>H3 and L 12 >L 13 In this way, the signal path of the wafer edge finding device can form a certain angle with the horizontal plane and the vertical direction, so that the relative position of the signal path and the wafer can be adjusted by adjusting H1, H2 or H3 later.

[0038] It should be noted that the explanation of the height adjustment of at least one of the stage 101 , the first bracket 203 , and the second bracket 204 is as follows.

[0039] For example, the height of the first bracket 203 and the second bracket 204 can remain unchanged, that is, the signal path formed between the signal transmitter 201 and the signal receiver 202 is fixed, and the stage 101 is configured as a height-adjustable structure. In this way, when the size of the wafer to be edge-finded is different, the height of the stage 101 can be adjusted so that when the wafer is rotated to a predetermined position, the signal path can pass through the V-groove at the edge of the wafer.

[0040] For another example, the height of the stage 101 can remain unchanged, and one or both of the first bracket 203 and the second bracket 204 are configured as a height-adjustable structure, that is, the signal path formed between the signal transmitter 201 and the signal receiver 202 is adjustable. In this way, when the size of the wafer to be edge-finded is different, the height of the first bracket 203 and / or the second bracket 204 can be adjusted to change the signal path formed between the signal transmitter 201 and the signal receiver 202, so that when the wafer is rotated to a predetermined position, the signal path can pass through the V-groove at the edge of the wafer.

[0041] It should be noted that at least one of the stage 101, the first bracket 203, and the second bracket 204 may be a structure with manually adjustable height, which will not be listed one by one here. Alternatively, at least one of the stage 101, the first bracket 203, and the second bracket 204 may be a structure that is electrically driven for height adjustment. For example, the height adjustment of one or more of the stage 101, the first bracket 203, and the second bracket 204 may be achieved by integrating a height adjustment device, or directly using the height adjustment device as the stage 101, the first bracket 203, or the second bracket 204. Among them, the height adjustment device may be, but is not limited to, the following devices: a cylinder, a hydraulic cylinder, an electric push rod, a screw module, etc.

[0042] It should also be noted that the installation position of the signal transmitter 201 on the first bracket 203 and the installation position of the signal receiver 202 on the second bracket 204 can be fixed, that is, the signal transmitter 201 and the signal receiver 202 always maintain a fixed angle relative to each other. At this time, the first bracket 203 and the second bracket 204 are configured to maintain consistent directions and lifting heights when adjusting the height.

[0043] Alternatively, the mounting position of the signal transmitter 201 on the first bracket 203 and the mounting position of the signal receiver 202 on the second bracket 204 may be adjustable. For example, in one embodiment, the signal transmitter 201 is mounted on the top of the first bracket 203 in an adjustable angle form, and the signal receiver 202 is mounted on the top of the second bracket 204 in an adjustable angle form, and the angle adjustment plane of the signal transmitter 201 is coplanar with the angle adjustment plane of the signal receiver 202. When replacing wafers of other sizes, H2 or H3 may need to be adjusted. At this time, the connection direction of the signal transmitter 201 and the signal receiver 202 changes, so the angles of the signal transmitter 201 and the signal receiver 202 need to be adjusted accordingly, so that the direction of the signal path is consistent with the connection direction of the two, so that the signal can smoothly reach the signal receiver 202.

[0044] It should be noted that the angle adjustment of the signal transmitter 201 and the signal receiver 202 can be achieved by a manual adjustment mechanism. Alternatively, the angle adjustment of the signal transmitter 201 and the signal receiver 202 can be achieved by an electric drive mechanism. For example, a regulator is installed on both the signal transmitter 201 and the signal receiver 202, and the angle change of the signal transmitter 201 and / or the signal receiver 202 is achieved by the regulator. The regulator may include but is not limited to a servo motor, a steering gear, etc.

[0045] In one embodiment, the wafer edge detection device may include a controller 4, and the height adjustment of the stage 101, the first bracket 203, and the second bracket 204 is electrically driven, and the angle adjustment of the signal transmitter 201 and the signal receiver 202 is also achieved through an electric drive mechanism. The controller 4 can control at least one of the stage 101, the first bracket 203, and the second bracket 204 to rise and fall to adjust the height, and the controller 4 can control at least one of the signal transmitter 201 and the signal receiver 202 to adjust the angle. Specifically, the controller 4 processes the wafer size data and the signal obtained by the edge detection device 2, and controls the height adjustment of the stage 101, the first bracket 203, and / or the second bracket 204, and controls the angle adjustment of the signal transmitter 201 and the signal receiver 202.

[0046] Among them, various parameters of the wafer edge-finding device can be pre-set in the controller 4. After the wafer diameter is input, the controller 4 calculates the required H1, H2 and H3 values, and controls the height of the stage 101, the first bracket 203 and / or the second bracket 204, and adjusts the angles of the signal transmitter 201 and the signal receiver 202 at the same time, so that the signal path can pass through the V-groove at the edge of the wafer.

[0047] In one embodiment, the diameter of the wafer to be processed ranges from D±d, and the depth of the V-groove ranges from V h ±h, the horizontal distance between the center line of the first bracket 203 and the center line of the second bracket 204 is L 23 , H1, H2, H3 and L 12 , L 23 The value of satisfies the following formula:

[0048]

[0049] Among them, V h -h>d;L 12 >1 / 2(D+d). M and N are safety factors, where M>1 and N>1. Specifically, they can be set to M=1.05 and N=1.05. K is the adjustment coefficient, 0<K<1. Due to the existence of safety factors M and N, no matter what the actual wafer diameter and V-groove depth are, the signal path always at least partially falls on the wafer edge area, thereby ensuring that the subsequent edge search process can be carried out smoothly.

[0050] like Figure 5-Figure 7 As shown, the distance from the position where the signal transmitter 201 is emitted to the height plane of the wafer to the edge of the wafer diameter D is f. After the values ​​of H1, H2, and H3 are determined, Established, where Z is the safety factor, Z ≥ 1.2.

[0051] In one embodiment, if Figure 3 As shown, the wafer tray 102 includes a tray rack 121, at least three retractable connecting rods 122 fixedly arranged around the tray rack 121, and a support portion 123 arranged at the free end of each connecting rod 122. The center of the tray rack 121 is fixedly connected to the top of the stage 101, and the upper surface of the support portion 123 is higher than the upper surfaces of the connecting rods 122 and the tray rack 121. Figure 1 As shown, when in use, the peripheral edge of the wafer rests on the upper surface of the plurality of support portions 123 .

[0052] Preferably, the connecting rods 122 are centrally symmetrically distributed relative to the center of the wafer tray 102. Figure 1 and Figure 2 As shown, when the wafer is lifted, since the upper surface of the support portion 123 is higher than the tray rack 121 and the connecting rod 122, the effective portion within the circumference of the wafer is suspended, thereby effectively avoiding damage caused by squeezing.

[0053] Among them, the retractable connecting rod 122 can directly adopt a retractable device, or can be driven to retract by a retractable device. The retractable device can adopt but is not limited to an electric push rod, a cylinder, a linear displacement module (such as a lead screw, a synchronous belt), etc. In addition, a controller 4 can be set, and various parameters of the wafer edge finding device can be pre-set in the controller 4. After the wafer diameter is input, the controller 4 calculates the required length value of the connecting rod 122, and controls and adjusts the telescopic length of the connecting rod 122 to adapt to the wafer of the corresponding size.

[0054] In one embodiment, if Figure 1 and Figure 2 As shown, each support portion 123 is provided with a limiting portion 124 at an edge away from the tray rack 121, and the limiting portion 124 is higher than the upper surface of the support portion 123. When the peripheral portion of the wafer is placed on the upper surfaces of the plurality of support portions 123, the edge of the wafer is located inside the limiting portion 124.

[0055] During the rotation of the carrier 1, due to the presence of the limiting portion 124, the wafer can be more securely restricted above the wafer tray 102 and cannot be displaced in the horizontal plane. This design helps to avoid accidents such as the wafer being thrown out or falling during the rotation process.

[0056] In one embodiment, if Figure 2 and Figure 3As shown, the limiting portion 124 is provided with an arc-shaped fitting surface 125 on one side close to the center of the tray rack 121. When in use, the fitting surface 125 matches the shape of the edge of the wafer. Among them, the arc center of the fitting surface 125 coincides with the center of the tray rack 121, and the fitting surface 125 matches the shape of the edge of the wafer. When in use, the fitting surface 125 fits the edge of the wafer to achieve the limiting of the wafer. The arc-shaped fitting surface 125 can form a surface contact with the edge of the wafer. Compared with the line contact formed by the straight fitting surface, its limiting effect is better, the probability of causing damage to the wafer is smaller, and the surface contact helps to increase the friction between the fitting surface 125 and the edge of the wafer, so that the wafer can be more reliably limited above the wafer tray 102.

[0057] In addition, a first buffer layer for preventing collisions may be provided on the bonding surface 125 to prevent the wafer edge from colliding with the bonding surface 125 during transportation and causing damage to the wafer. The first buffer layer may be made of a soft elastic material so as to play a certain clamping role on the wafer edge and improve the limiting effect of the limiting portion 124 on the wafer. In addition, a second buffer layer for preventing collisions and increasing friction may be provided on the upper surface of the support portion 123 to reduce the probability of damage to the wafer when it is taken and placed, and to reduce the possibility of the wafer moving during transportation.

[0058] like Figure 8 As shown, this embodiment also provides a wafer edge finding method, using a wafer edge finding device, the wafer edge finding device includes a base 3, a carrier 1 and an edge detection device 2. Among them, the carrier 1 is installed on the base 3, including a rotatable and height-adjustable stage 101 and a wafer tray 102 installed on the top of the stage 101, and the rotation axis of the stage 101 is along the vertical direction and passes through the center of the wafer tray 102. The edge detection device 2 includes a signal transmitter 201, a signal receiver 202, a first bracket 203 with adjustable height, and a second bracket 204 with adjustable height. The second bracket 204 is arranged on the base 3 below the wafer tray 102, and the signal receiver 202 is installed on the top of the second bracket 204 in an adjustable angle form. The first bracket 203 is arranged on the base 3 at the side position of the wafer tray 102, and the signal transmitter 201 is installed on the top of the first bracket 203 in an adjustable angle form, and the signal transmitter 201 is higher than the wafer tray 102 when in use. The signal receiver 202 is opposite to the signal transmitter 201. The angle adjustment plane of the signal transmitter 201 is coplanar with the angle adjustment plane of the signal receiver 202. The height of the stage 101 is H1, the height of the first bracket 203 is H2, and the height of the second bracket 204 is H3.

[0059] Wafer edge finding methods include:

[0060] S1. Place the wafer whose edge is to be found on the wafer tray 102 and make the V-groove on the edge of the wafer unobstructed, so that the rotation axis of the stage 101 passes through the center of the wafer.

[0061] S2. Based on the diameter of the wafer and the depth of the V-groove at the edge of the wafer, adjust the height of at least one of H1, H2, and H3, and adjust the angles of the signal transmitter 201 and the signal receiver 202 so that the signal transmission path coincides with the signal reception path.

[0062] S3, the stage 101 drives the wafer to rotate, and during the rotation process, it is determined whether the signal receiver 202 receives the signal from the signal transmitter 201 within a specific time period. If yes, it means that the signal path from the signal transmitter 201 to the signal receiver 202 passes through the V-groove, and the wafer edge finding is completed; if no, the rotation is stopped, and steps S2-S3 are repeated.

[0063] In step S1, the edge of the wafer can be mounted on the support part 123 manually or by a robot arm so that the rotation axis of the stage 101 passes through the center of the wafer. If it is observed that the V-groove of the wafer is located above the support part 123 at this time, the wafer is taken out directly upward, the carrier 1 is rotated by a preset angle α, and then the edge of the wafer is re-mounted on the support part 123 and the rotation axis of the stage 101 passes through the center of the wafer. At this time, the V-groove is no longer located above the support part 123. Among them, the angle α can be determined according to the number of support parts 123 and the width of each support part 123. It is only necessary to ensure that the signal can pass normally at the V-groove after the carrier 1 rotates by an angle α.

[0064] In step S3, if the signal receiver 202 can always receive the signal, it means that the signal always falls outside the edge of the wafer. If the signal receiver 202 cannot always receive the signal, it means that the signal always falls within the edge of the wafer, and the V-groove at the edge of the wafer cannot be located. Therefore, H1, H2, and H3 need to be readjusted so that the signal falls on the edge of the wafer. When the V-groove rotates to the signal path, the signal can reach the signal receiver 202 through the V-groove. When the V-groove rotates away from the signal path, the signal will be blocked by the edge of the wafer, that is, the signal receiver 202 can receive the signal within a specific time period, and wafer edge finding is achieved at this time.

[0065] In one embodiment, in step S2, the diameter of the wafer to be processed ranges from D±d, and the depth of the V-groove ranges from V h ±h, the horizontal distance between the center line of the stage 101 and the center line of the first bracket 203 is L 12 The horizontal distance between the center line of the first bracket 203 and the center line of the second bracket 204 is L 23 The values ​​of H1, H2, and H3 satisfy the following formula:

[0066]

[0067] Among them, V h -h>d;L 12 >1 / 2(D+d). M and N are safety factors, both of which are greater than 1. K is the adjustment factor, 0<K<1. Due to the existence of safety factors M and N, no matter what the actual wafer diameter and V-groove depth are, the signal path always at least partially falls on the wafer edge area, thereby ensuring that the subsequent edge search process can be carried out smoothly.

[0068] like Figure 5-Figure 7 As shown, the distance from the position where the signal transmitter 201 is emitted to the height plane of the wafer to the edge of the wafer diameter D is f. After the values ​​of H1, H2, and H3 are determined, Established, where Z is the safety factor, Z ≥ 1.2.

[0069] The above description is only the preferred embodiment of the present application and is not intended to limit the present application. For those skilled in the art, the present application may have various modifications and variations. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present application shall be included in the protection scope of the present application.

Claims

1. A wafer edge finding device, characterized in that: include: abutment(3); A carrier platform (1) is mounted on the base platform (3), comprising a rotatable carrier platform (101) and a wafer tray (102) mounted on the top of the carrier platform (101), wherein the rotation axis of the carrier platform (101) is along a vertical direction and passes through the center of the wafer tray (102); An edge detection device (2), comprising a signal transmitter (201), a signal receiver (202), a first bracket (203) and a second bracket (204); the second bracket (204) is arranged on the base (3) below the wafer tray (102), and the signal receiver (202) is installed on the top of the second bracket (204); the first bracket (203) is arranged on the base (3) at the side of the wafer tray (102), the signal transmitter (201) is installed on the top of the first bracket (203), and the signal transmitter (201) is higher than the wafer tray (102) when in use; the signal receiver (202) is opposite to the signal transmitter (201); Wherein, at least one of the loading platform (101), the first bracket (203) and the second bracket (204) is configured as a height-adjustable structure.

2. The wafer edge-finding device according to claim 1, characterized in that: The center lines of the object carrier (101), the first bracket (203) and the second bracket (204) are located in the same plane.

3. The wafer edge-finding device according to claim 2, characterized in that: The horizontal distance between the center line of the loading platform (101) and the center line of the first bracket (203) is L. 12 The horizontal distance between the center line of the stage (101) and the center line of the second bracket (204) is L 13 ; The height of the loading platform (101) is H1, the height of the first bracket (203) is H2, and the height of the second bracket (204) is H3; Among them, H2>H1>H3 and L 12 >L 13 .

4. The wafer edge-finding device according to claim 3, characterized in that: The signal transmitter (201) is mounted on the top of the first bracket (203) in a manner that allows for an adjustable angle, and the signal receiver (202) is mounted on the top of the second bracket (204) in a manner that allows for an adjustable angle, and the angle adjustment plane of the signal transmitter (201) is coplanar with the angle adjustment plane of the signal receiver (202).

5. The wafer edge-finding device according to claim 4, characterized in that: The diameter of the wafer to be processed ranges from D±d, and the depth of the V-groove ranges from V h ±h, the horizontal distance between the center line of the first bracket (203) and the center line of the second bracket (204) is L 23 , then H1, H2, H3 and L 12 , L 23 The value of satisfies the following formula: Among them, V h -h>d;L 12 >1 / 2(D+d); M and N are safety factors, both of which are greater than 1; K is the adjustment coefficient, 6. The wafer edge-finding device according to claim 1, characterized in that: The wafer tray (102) comprises a tray rack (121), at least three retractable connecting rods (122) fixedly arranged around the tray rack (121), and a support portion (123) arranged at the free end of each connecting rod (122), the center of the tray rack (121) is fixedly connected to the top of the stage (101), and the upper surface of the support portion (123) is higher than the upper surfaces of the connecting rods (122) and the tray rack (121); When in use, the peripheral edge of the wafer rests on the upper surfaces of the plurality of support portions (123).

7. The wafer edge-finding device according to claim 6, characterized in that: Each of the supporting portions (123) is provided with a limiting portion (124) at an edge on a side away from the tray rack (121), and the limiting portion (124) is higher than an upper surface of the supporting portion (123); When the peripheral edge of the wafer is placed on the upper surfaces of the plurality of support portions (123), the edge of the wafer is located inside the limiting portion (124).

8. The wafer edge-finding device according to claim 7, characterized in that: The limiting portion (124) is provided with an arc-shaped fitting surface (125) on one side close to the center of the tray frame (121); When in use, the bonding surface (125) matches the shape of the edge of the wafer.

9. A wafer edge finding method, characterized in that: Using a wafer edge-finding device, the wafer edge-finding device comprises a base (3), a carrier (1) and an edge detection device (2); The carrier platform (1) is mounted on the base platform (3), and comprises a rotatable and height-adjustable loading platform (101) and a wafer tray (102) mounted on the top of the loading platform (101), wherein the rotation axis of the loading platform (101) is along the vertical direction and passes through the center of the wafer tray (102); The edge detection device (2) comprises a signal transmitter (201), a signal receiver (202), a first bracket (203) with adjustable height, and a second bracket (204) with adjustable height; the second bracket (204) is arranged on the base (3) below the wafer tray (102), and the signal receiver (202) is installed on the top of the second bracket (204) in an angle-adjustable manner; the first bracket (203) is arranged on the base (3) at the side of the wafer tray (102), and the signal transmitter (201) is installed on the top of the first bracket (203) in an angle-adjustable manner, and the signal transmitter (201) is higher than the wafer tray (102) when in use; the signal receiver (202) is opposite to the signal transmitter (201); the angle adjustment plane of the signal transmitter (201) is coplanar with the angle adjustment plane of the signal receiver (202); The height of the loading platform (101) is H1, the height of the first bracket (203) is H2, and the height of the second bracket (204) is H3; The wafer edge finding method comprises: S1, placing the wafer whose edge is to be found on the wafer tray (102) and leaving the V-groove at the edge of the wafer in an unobstructed state, so that the rotation axis of the stage (101) passes through the center of the wafer; S2, based on the diameter of the wafer and the depth of the V-groove at the edge of the wafer, adjusting the height of at least one of H1, H2, and H3, and adjusting the angles of the signal transmitter (201) and the signal receiver (202) so that the signal transmission path coincides with the signal reception path; S3, causing the stage (101) to drive the wafer to rotate, and during the rotation process, determining whether the signal receiver (202) receives the signal from the signal transmitter (201) within a specific time period; if so, it indicates that the signal path from the signal transmitter (201) to the signal receiver (202) passes through the V-groove, completing wafer edge finding; if not, stopping the rotation and repeating steps S2-S3.

10. The wafer edge finding method according to claim 9, characterized in that: In step S2, the diameter of the wafer to be processed ranges from D±d and the depth of the V-groove ranges from V h ±h, the horizontal distance between the center line of the stage (101) and the center line of the first support (203) is L 12 The horizontal distance between the center line of the first bracket (203) and the center line of the second bracket (204) is L 23 ; then H1, H2, H3 and L 12 , L 23 The value of satisfies the following formula: Among them, V h -h>d;L 12 >1 / 2(D+d); M and N are safety factors, both of which are greater than 1; K is the adjustment factor,

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