Wafer pre-alignment device, semiconductor equipment and pre-alignment method

Abstract

The invention provides a wafer pre-alignment device, semiconductor equipment and a pre-alignment method. The wafer pre-alignment device comprises a main body frame, a rotating mechanism, a centering mechanism and an alignment assembly. The rotating mechanism is installed on the main body frame and comprises a rotatable suction cup, the rotating axis is in the Z direction, and the upper surface of the suction cup is configured to be a bearing face capable of achieving negative pressure adsorption. The centering mechanism is installed on the main body frame and is configured to drive the position of the wafer placed on the suction cup to be adjusted so that the center of the wafer can coincide with the center of the bearing face. The alignment assembly comprises a reflection part and an alignment sensor, the reflection part is arranged below the bearing surface, the alignment sensor is erected above the bearing surface, and the alignment sensor directly faces the reflection part. After the center of the wafer coincides with the center of the bearing surface and the wafer rotates to a preset angle, the light beam path of the alignment sensor passes through the vacant area at the edge of the wafer. According to the invention, the pre-alignment process of the wafer is realized through a non-visual method, the pre-alignment efficiency is improved, and the pre-alignment precision can be effectively ensured.

Description

Technical Field

[0001] The present application relates to the technical field of wafer defect detection, and in particular to a wafer pre-alignment device, semiconductor equipment, and a pre-alignment method. Background Art

[0002] In semiconductor manufacturing, high-precision defect detection is crucial to ensuring chip yield. Defect detection equipment must precisely scan the wafer surface to identify micro- and nano-scale defects. A prerequisite for achieving this goal is precise pre-alignment, which determines the position and orientation of the wafer in the inspection coordinate system. Figure 11 and Figure 12 Wafer edges typically have positioning features (such as flat edges or notches), and pre-alignment requires quickly and accurately adjusting these features to their standard positions. In this application, the area formed by the edge of a wafer's positioning feature and the circumference of the wafer's diameter is referred to as the "vacant area." The accuracy and efficiency of pre-alignment have a significant impact on subsequent inspections.

[0003] Among the current mainstream technologies, high-resolution cameras are often used to capture images of the wafer edge, and complex image processing algorithms (such as edge detection, feature extraction, etc.) are used to identify positioning features, calculate offsets and rotation angles, and drive the platform to compensate for the positioning features of the wafer to achieve the purpose of pre-alignment. However, this method has significant limitations: high-resolution image acquisition, transmission, and complex algorithm processing are time-consuming, which restricts the pre-alignment speed and equipment efficiency; the algorithm is susceptible to changes in wafer edge images, uneven lighting, and contamination interference, which may lead to recognition failure or reduced accuracy; system accuracy is limited by factors such as camera resolution and lens distortion; and it requires the integration of high-resolution cameras, dedicated image processing hardware, precision lighting, and complex software, increasing system cost and maintenance difficulty. The limitations of the aforementioned methods may lead to serious alignment errors in the wafer during the pre-alignment process.

[0004] If the pre-alignment error is too large, the scanning path for subsequent defect detection may not accurately cover the target area, easily leading to missed or false detections, and seriously affecting the accuracy of defect identification. Given the shortcomings of existing vision alignment methods in terms of speed, accuracy, and cost control, it is imperative to develop a relatively better pre-alignment device. Summary of the Invention

[0005] The purpose of this application is to provide a wafer pre-alignment device, semiconductor equipment and pre-alignment method, which realizes the wafer pre-alignment process through a non-visual method, improves the pre-alignment efficiency, and can effectively ensure the pre-alignment accuracy.

[0006] In the first aspect, a wafer pre-alignment device is provided, comprising a main frame, a rotating mechanism, a centering mechanism and an alignment assembly. The rotating mechanism is mounted on the main frame, and comprises a rotatable suction cup, wherein the axis of rotation is along the Z direction, the upper surface of the suction cup is configured as a bearing surface with negative pressure adsorption capability, and the axis of rotation passes through the center of the bearing surface. The centering mechanism is mounted on the main frame, and is configured to drive the position adjustment of the wafer placed on the suction cup so that the center of the wafer coincides with the center of the bearing surface. The alignment assembly comprises a reflecting part and an alignment sensor, wherein the reflecting part is arranged below the bearing surface, the alignment sensor is mounted above the bearing surface, and the alignment sensor is directly opposite to the reflecting part. After the center of the wafer coincides with the center of the bearing surface, and when the suction cup adsorbs the wafer and rotates to a predetermined angle, the light beam path between the alignment sensor and the reflecting part passes through the vacant area at the edge of the wafer.

[0007] In one feasible solution, the centering mechanism includes at least two centering parts capable of moving toward and away from each other, and the centering parts are arc-shaped; the suction cup of the rotating mechanism is located between the centering parts, and the axis of rotation coincides with the center of the area surrounded by the centering parts; wherein, when all the centering parts move toward each other until the wafer on the suction cup is clamped, the center of the wafer coincides with the center of the supporting surface.

[0008] In an implementable solution, each centering piece is provided with at least two steps of different heights and at different distances from the suction cup, the steps are arc-shaped, and the step away from the suction cup is higher than the step close to the suction cup; the diameter of the circular area enclosed by the arc side walls of the steps of multiple centering pieces at the same height is adapted to the diameter of the corresponding wafer; the centering mechanism includes a centering drive device and a lifting device; the lifting device is installed on the main frame, the centering drive device is installed on the lifting device, and the centering drive device is connected to the centering piece; the lifting device is used to drive all the centering pieces to rise or fall at the same time, so that the side walls of the steps in the centering piece that are adapted to the diameter of the corresponding wafer are at the same height as the wafer; the centering drive device is used to drive the centering pieces to move toward or away from each other at the same time.

[0009] In one feasible solution, the stepped side walls of different heights of multiple centering members enclose multiple circular areas with different diameters, an alignment sensor is mounted above the edge of each circular area, and a corresponding reflective portion is provided on a predetermined structural surface below the corresponding bearing surface of each alignment sensor.

[0010] In an implementable scheme, the centering mechanism includes a horizontally arranged centering frame plate, and the displacement output end of the lifting device is connected to the centering frame plate; the centering drive device includes a track, a turntable, and a power assembly; multiple tracks are installed on the upper surface of the centering frame plate and are arranged around the center of the suction cup, and each track extends radially along the suction cup; a centering piece is slidably installed on each track; the turntable is located below the suction cup and is rotatably installed on the centering frame plate, and the rotation axis of the turntable coincides with the rotation axis of the suction cup; at least the same number of arc grooves as the number of centering pieces are provided on the turntable, and the arc grooves are eccentrically arranged and evenly distributed around the center circumference of the turntable, and the center of the arc grooves does not coincide with the center of the turntable; a cylindrical piece is provided on the centering piece and inserted into the arc groove, and the cylindrical piece is restricted to move in the arc groove; the power assembly is installed on the centering frame plate and is used to drive the turntable to rotate.

[0011] In an implementable solution, the power assembly includes a linear displacement mechanism, a push rod and a spring; a slide groove is provided on the turntable; the linear displacement mechanism is installed on the centering frame plate, the first end of the push rod is pivotally connected to the displacement output end of the linear displacement mechanism, the second end of the push rod is restricted to slide in the slide groove, and a spring is provided between the second end of the push rod and the bottom wall of the slide groove, and the two ends of the spring are always in contact with the second end of the push rod and the bottom wall of the slide groove respectively.

[0012] In an implementable scheme, the wafer pre-alignment device also includes an information reading device, and at least an unobstructed through-area in the upper and lower directions is reserved in the main frame and / or the centering mechanism, and the reading end of the information reading device is facing the through-area; the information reading device is installed on the main frame and is below the through-area, and the reading end of the information reading device is facing the through-area; the rotating mechanism drives the wafer to rotate so that the identity information identification code on the back of the wafer faces the through-area; the information reading device is used to read the identity information identification code on the back of the wafer through the through-area.

[0013] In an implementable solution, the rotating mechanism also includes a rotating power device, a rotating shaft and a pneumatic joint; the rotating shaft is installed on the rotating power device, the rotating power device is used to drive the rotating shaft to rotate, a suction cup is installed on the top of the rotating shaft, and the top is connected to the pneumatic joint; an air path is provided inside the rotating shaft for connecting the pneumatic joint and the bearing surface of the suction cup.

[0014] In an implementable solution, the wafer pre-alignment device also includes a cache component, which includes a cache frame and an in-situ detection sensor; the cache frame is installed on the main frame, and the cache frame is provided with multiple accommodating areas for accommodating wafers of different sizes; the middle position of the cache frame is installed with an in-situ detection sensor for detecting whether there are wafers accommodated on the cache frame.

[0015] In an implementable solution, the wafer pre-alignment device further includes a cleaning component, which includes a cleaning nozzle disposed above the suction cup, with an output end of the cleaning nozzle facing the suction cup.

[0016] In a second aspect, the present application provides a semiconductor device comprising the aforementioned wafer pre-alignment apparatus.

[0017] In a third aspect, the present application provides a pre-alignment method for the aforementioned wafer pre-alignment device, comprising:

[0018] Place the wafer on the supporting surface of the suction cup and control the supporting surface to maintain a negative pressure state;

[0019] The centering mechanism drives the wafer placed on the suction cup to adjust its position until the center of the wafer coincides with the center of the support surface, after which the centering mechanism and the wafer are separated;

[0020] Control the carrying surface of the suction cup to generate negative pressure to absorb the wafer;

[0021] Control the rotation of the suction cup of the rotating mechanism to drive the wafer to rotate, and identify the vacant area at the edge of the wafer through the alignment sensor;

[0022] Determine the current azimuth angle of the wafer by aligning the information of the vacant area on the edge of the wafer identified by the sensor;

[0023] The suction cup of the rotating mechanism is controlled to rotate to adjust the azimuth angle of the wafer. When the azimuth angle of the wafer is adjusted to the desired angle, the pre-alignment process of the wafer is completed.

[0024] Compared with the prior art, the beneficial effects of the present application include at least: in the wafer pre-alignment device of the present application, the center position of the wafer is adjusted by a centering mechanism, and then the vacant area on the edge of the wafer is detected by a vertically arranged alignment sensor (i.e., the positioning features of the wafer are identified) to determine the azimuth angle of the wafer, and then the wafer is rotated by a rotating mechanism to adjust the azimuth angle of the wafer to the desired angle, thereby completing the wafer pre-alignment process.

[0025] It can be seen from this that the wafer pre-alignment device of the present application does not need to extract the image of the wafer by taking pictures with a camera, nor does it need to analyze the image to identify the positioning features of the wafer during the wafer pre-alignment process, which helps to improve the efficiency of pre-alignment. At the same time, compared with the method of analyzing the wafer image to identify the orientation of the wafer positioning features, the present application uses the method of aligning the sensor to identify the vacant area on the edge of the wafer, which has a high recognition success rate and accurate positioning accuracy, thus helping to reduce pre-alignment errors and improve alignment accuracy. The improvement in pre-alignment efficiency, that is, the improvement in alignment accuracy, helps to ensure that the scanning path of subsequent defect detection accurately covers the target area, reduces the risk of missed detection or false detection, and thus ensures the accuracy of wafer defect discrimination. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] In order to more clearly illustrate the technical solutions of the embodiments of the present application, the following is a brief introduction to the drawings required for use in the embodiments. 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 relevant drawings can be obtained based on these drawings without creative work.

[0027] Figure 1 A three-dimensional diagram of a wafer pre-alignment device shown in an embodiment of the present application;

[0028] Figure 2 for Figure 1 A partial magnified view of the alignment area of ​​the wafer;

[0029] Figure 3 for Figure 1 Schematic diagram of the main frame;

[0030] Figure 4 A three-dimensional diagram of a centering mechanism shown in an embodiment of the present application;

[0031] Figure 5 for Figure 4 Top view of the centering mechanism;

[0032] Figure 6 A three-dimensional diagram of a local structure for performing a wafer centering operation according to an embodiment of the present application;

[0033] Figure 7 for Figure 6 Side view of the mid-structure;

[0034] Figure 8 A three-dimensional diagram of a rotating mechanism shown in an embodiment of the present application;

[0035] Figure 9 for Figure 8 A three-dimensional diagram of the rotating mechanism carrying a wafer;

[0036] Figure 10 for Figure 9 Front view of the structure.

[0037] Figure 11 and Figure 12 A schematic diagram of a wafer and its edge having positioning features in the prior art.

[0038] In the figure: 1. Main frame; 2. Rotating mechanism; 21. Suction cup; 211. Bearing surface; 22. Rotating power device; 23. Rotating axis; 24. Pneumatic joint; 3. Centering mechanism; 31. Centering part; 311. Step; 312. Cylindrical part; 32. Lifting device; 33. Centering drive device; 331. Track; 332. Turntable; 3321. Arc groove; 3322. Slide groove; 333. Power assembly; 3331. Linear displacement mechanism; 3332. Push rod; 3333. Spring; 34. Centering frame plate; 4. Reflecting part; 5. Alignment sensor; 6. Information reading device; 7. Through area; 8. Cache assembly; 81. Cache frame; 82. In-situ detection sensor; 9. Cleaning nozzle; 10. Wafer; 01. Flat edge; 02. Notch; 03. Vacant area. DETAILED DESCRIPTION

[0039] To make the objectives, technical solutions, and advantages of the embodiments of the present application more clear, the technical solutions in the embodiments of the present application will be clearly and completely described below in conjunction with the accompanying drawings of the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, not all of the embodiments. Generally, the components of the embodiments of the present application described and shown in the drawings herein can be arranged and designed in various different configurations.

[0040] 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 protection, but merely represents selected embodiments of the present application. All other embodiments obtained by persons of ordinary skill in the art based on the embodiments in the present application without creative work are within the scope of protection of the present application.

[0041] like Figure 1 and Figure 2As shown, an embodiment of the present application first provides a wafer pre-alignment device, including a main frame 1, a rotating mechanism 2, a centering mechanism 3 and an alignment assembly. The rotating mechanism 2 is mounted on the main frame 1, and includes a rotatable suction cup 21, the axis of rotation is along the Z direction, the upper surface of the suction cup 21 is configured as a carrying surface 211 with negative pressure adsorption capability, and the axis of rotation passes through the center of the carrying surface 211. The suction cup 21 is used to carry the wafer 10 and drive the wafer 10 to rotate. The centering mechanism 3 is mounted on the main frame 1, and is configured to drive the position of the wafer placed on the suction cup 21 to adjust so that the center of the wafer coincides with the center of the carrying surface 211. The alignment assembly includes a reflecting part 4 and an alignment sensor 5, the reflecting part 4 is arranged below the carrying surface 211, the alignment sensor 5 is mounted above the carrying surface 211, and the alignment sensor 5 is directly opposite to the reflecting part 4. The alignment sensor 5 adopts a reflective sensor, such as an infrared sensor. The reflective material can be attached to the structural surface below the bearing surface 211, for example, to the main structural surface of the centering mechanism 3 or the predetermined structural surface of the main frame 1, thereby forming the reflective portion 4. Alternatively, the reflective material can be pre-attached to the surface of a block structure, and then the block structure can be installed at a predetermined position to form the reflective portion 4.

[0042] After the center of the wafer coincides with the center of the carrying surface 211 and the suction cup 21 absorbs the wafer and rotates to a predetermined angle, the light beam path between the alignment sensor 5 and the reflective portion 4 passes through the vacant area at the edge of the wafer.

[0043] See also Figure 11 and Figure 12 , the edge of the wafer 10 usually has positioning features (such as a flat edge 01 or a notch 02), and the goal of pre-alignment is to adjust these positioning features to the standard position. Among them, the application refers to the area formed by the edge of the positioning feature of the wafer 10 and the circumference of the diameter of the wafer 10 as the vacant area 03. When the vacant area 03 of the wafer 10 rotates and passes under the alignment sensor 5, the light beam path of the alignment sensor 5 passes through this vacant area 03, and the light beam reaches the surface of the reflecting part 4 and is then reflected back. The reflected light beam is received by the alignment sensor 5, thereby identifying the vacant area on the edge of the wafer 10, and the azimuth angle of the wafer 10 can be determined based on this, and then the orientation of the wafer 10 can be adjusted.

[0044] Specifically, when the wafer pre-alignment device of this embodiment pre-aligns the wafer 10, first, the wafer 10 is placed on the supporting surface 211 of the suction cup 21, and the supporting surface 211 is controlled to maintain a negative pressure state. Then, the centering mechanism 3 drives the wafer 10 placed on the suction cup 21 to adjust its position until the center of the wafer coincides with the center of the supporting surface 211, and then the centering mechanism 3 and the wafer 10 are separated. Next, the supporting surface 211 of the suction cup 21 is controlled to generate negative pressure to adsorb the wafer 10, and the suction cup 21 of the rotating mechanism 2 is controlled to rotate to drive the wafer 10 to rotate, and the alignment sensor 5 is used to identify the vacant area at the edge of the wafer 10. The current azimuth angle of the wafer 10 is determined by the information of the vacant area at the edge of the wafer 10 identified by the alignment sensor 5. Then, the suction cup 21 of the rotating mechanism 2 is controlled to rotate to adjust the azimuth angle of the wafer 10. When the azimuth angle of the wafer 10 is adjusted to the desired angle, the pre-alignment process of the wafer 10 is completed.

[0045] Among them, since the vacant area on the edge of the wafer 10 has a certain range, after the alignment sensor 5 identifies the vacant area, the wafer 10 can be rotated forward and backward so that the alignment sensor 5 can accurately identify the edge of the vacant area, and combined with the recorded rotation angle of the suction cup 21, the azimuth angle of the wafer 10 can be accurately located.

[0046] In summary, in the wafer pre-alignment device of the present embodiment, the centering position adjustment of the wafer is realized by the centering mechanism 3, and then the vacant area of ​​the edge of the wafer 10 is detected by the vertically arranged alignment sensor 5 (i.e., the positioning feature of the wafer 10 is identified) to determine the azimuth of the wafer 10, and then the wafer 10 is rotated by the rotating mechanism 2 to adjust the azimuth of the wafer 10 to the desired angle, thereby completing the pre-alignment process of the wafer 10. It can be seen from this that the wafer pre-alignment device of the present embodiment does not need to extract the image of the wafer 10 by taking pictures with a camera, nor does it need to analyze the image to identify the positioning feature of the wafer 10 during the wafer pre-alignment process, which greatly reduces the amount of data processing, and this helps to improve the efficiency of pre-alignment. At the same time, compared with the method of analyzing the wafer image to identify the orientation of the wafer positioning feature, the present application identifies the vacant area of ​​the edge of the wafer 10 by the alignment sensor 5, and the recognition success rate is high, and the positioning accuracy is accurate, thus helping to reduce the pre-alignment error and improve the alignment accuracy. Improved pre-alignment efficiency, that is, improved alignment accuracy, helps ensure that the scanning path of subsequent defect detection accurately covers the target area, reducing the risk of missed detection or false detection, thereby ensuring the accuracy of wafer defect judgment.

[0047] In addition, due to the way in which the alignment sensor 5 identifies the vacant area at the edge of the wafer 10 , the cost of the sensor components used is lower, which is more conducive to cost control.

[0048] It should be noted that the wafer pre-alignment apparatus of this embodiment includes a controller, which is electrically connected to the rotation mechanism 2, the centering mechanism 3, and the alignment sensor 5. The controller controls the movement of the rotation mechanism 2 and the centering mechanism 3 and receives signals from the alignment sensor 5, thereby ensuring the completion of the pre-alignment process. Because the specific control methods for the controller to receive signals from the alignment sensor 5, process the signals, and control the movement of the rotation mechanism 2 and the centering mechanism 3 are not limited to a single one, the specific control processes will not be listed here one by one.

[0049] In some embodiments, as Figure 4 、 Figure 5 and Figure 6 As shown, the centering mechanism 3 may include at least two centering members 31 capable of moving toward and away from each other, and the centering members 31 are arc-shaped. Figure 4 and Figure 5 In the embodiment, the centering mechanism 3 may include two centering members 31. The suction cups 21 of the rotating mechanism 2 are located between the centering members 31, and the axis of rotation coincides with the center of the area surrounded by the centering members 31. When all the centering members 31 move toward each other until the wafer on the suction cups 21 is clamped, the center of the wafer coincides with the center of the support surface 211.

[0050] It should be noted that all centering members 31 are at the same distance from the center of the suction cup 21, and their movement toward or away from each other is synchronized. The wall surface of the centering member 31 that contacts the edge of the wafer 10 is an arc-shaped side wall that matches the diameter of the wafer 10, thereby ensuring the accuracy of the centering.

[0051] In some embodiments, as Figure 4 、 Figure 5 and Figure 7 As shown, each centering member 31 can be provided with at least two steps 311 of different heights and different distances from the suction cup 21. The steps 311 are arc-shaped, and the step 311 on the side away from the suction cup 21 is higher than the step 311 on the side close to the suction cup 21. The diameter of the circular area enclosed by the arc side walls of the steps 311 of multiple centering members 31 at the same height is adapted to the diameter of the corresponding wafer. The centering mechanism 3 includes a centering drive device 33 and a lifting device 32; the lifting device 32 is mounted on the main frame 1, the centering drive device 33 is mounted on the lifting device 32, and the centering drive device 33 is connected to the centering member 31.

[0052] The lifting device 32 is used to simultaneously raise or lower all centering members 31 so that the sidewalls of the steps 311 of the centering members 31, which correspond to the diameters of the corresponding wafers 10, are at the same height as the wafers 10. The lifting device 32 can be a pneumatic cylinder, an electric push rod, a lead screw module, etc. The centering drive device 33 is used to drive the centering members 31 to move toward or away from each other simultaneously.

[0053] For example, Figure 4、 Figure 5 and Figure 7 As shown, each centering member 31 is provided with two steps 311 at different heights and at different distances from the suction cup 21. The step 311 on the side away from the suction cup 21 is higher than the step 311 on the side closer to the suction cup 21. Among the multiple centering members 31, the step 311 on the side away from the suction cup 21 is called the first step. The diameter of the circular area enclosed by the arcuate sidewall of the first step is consistent with the diameter of a 6-inch wafer. The step 311 on the side closer to the suction cup 21 is called the second step. The diameter of the circular area enclosed by the arcuate sidewall of the second step is consistent with the diameter of a 4-inch wafer.

[0054] If a 4-inch wafer is placed on the supporting surface 211 of the suction cup 21, the lifting device 32 drives the centering member 31 to rise to a first height so that the arcuate sidewall of the first step is at the same height as the wafer 10. The two centering members 31 then move toward each other, so that the arcuate sidewalls of the first step on each centering member 31 are close to the edge of the wafer 10, until the arcuate sidewalls of the first step abut against and clamp the edge of the wafer 10, thereby completing the alignment of the center of the 4-inch wafer with the center of the supporting surface 211. After the alignment is completed, the centering members 31 move away from each other to disengage the sidewalls of the step from the edge of the wafer 10.

[0055] If a 6-inch wafer is placed on the supporting surface 211 of the suction cup 21, the lifting device 32 drives the centering member 31 to rise to the second height so that the arcuate sidewall of the second step is at the same height as the wafer 10. The two centering members 31 then move toward each other, so that the arcuate sidewalls of the second step on each centering member 31 are close to the edge of the wafer 10, until the arcuate sidewalls of the second step abut against and clamp the edge of the wafer 10, thereby completing the alignment of the center of the 6-inch wafer with the center of the supporting surface 211. After alignment is completed, the centering members 31 move away from each other to disengage the sidewalls of the step from the edge of the wafer 10.

[0056] In summary, it can be seen that in the centering mechanism 3 of this embodiment, by setting multiple steps 311 with different heights and different distances from the suction cup 21 on the centering part 31, such a design enables the centering mechanism 3 to be accurately compatible with wafers of various sizes, thereby achieving efficient centering operations, greatly broadening its scope of application, and effectively improving the versatility and flexibility of the equipment in different production scenarios.

[0057] In some embodiments, as Figure 2 As shown, the side walls of the steps 311 of different heights of the multiple centering members 31 form multiple circular areas with different diameters, an alignment sensor 5 is set above the edge of each circular area, and a corresponding reflective part 4 is set on the predetermined structural surface below the corresponding supporting surface 211 of each alignment sensor 5.

[0058] For example, the centering member 31 has two steps 311: a first step located away from the suction cup 21 and a second step 311 located closer to the suction cup 21. The first step is higher than the second step. The area enclosed by the sidewalls of the first step is used for centering 6-inch wafers, while the area enclosed by the sidewalls of the second step is used for centering 4-inch wafers. After the 6-inch and 4-inch wafers are aligned, an alignment sensor 5 is installed above the circumference of the missing area to detect and identify the missing area on the edges of wafers of different sizes.

[0059] Furthermore, in some embodiments, only one or more alignment sensors 5 may be provided, and each alignment sensor 5 is configured to be positionally adjustable within the horizontal plane in which it is located.

[0060] In some embodiments, as Figure 4 and Figure 5 As shown, the centering mechanism 3 may include a horizontally arranged centering frame plate 34, to which the displacement output end of the lifting device 32 is connected. The centering drive device 33 may include a track 331, a turntable 332, and a power assembly 333. Multiple tracks 331 are mounted on the upper surface of the centering frame plate 34 and arranged around the center of the suction cup 21. Each track 331 extends radially along the suction cup 21. A centering member 31 is slidably mounted on each track 331.

[0061] The turntable 332 is located below the suction cup 21 and is rotatably mounted on the centering frame plate 34. The rotation axis of the turntable 332 coincides with the rotation axis of the suction cup 21. The turntable 332 is provided with at least the same number of arcuate slots 3321 as the centering member 31. The arcuate slots 3321 are eccentrically arranged and evenly distributed around the center circumference of the turntable 332. The center of the arcuate slots 3321 does not coincide with the center of the turntable 332. The centering member 31 is provided with a cylindrical member 312, which is inserted into the arcuate slots 3321 and constrained to move within the arcuate slots 3321. The power assembly 333 is mounted on the centering frame plate 34 and is used to drive the turntable 332 to rotate.

[0062] After the power assembly 333 drives the turntable 332 to rotate, the arc-shaped groove 3321 drives the cylindrical member 312 to move along the track 331, thereby realizing the movement of the centering member 31 along the track to achieve the centering process.

[0063] In some embodiments, as Figure 4 and Figure 5As shown, the power assembly 333 may include a linear displacement mechanism 3331, a push rod 3332, and a spring 3333; a slide groove 3322 is provided on the turntable 332. The linear displacement mechanism 3331 may be a cylinder, an electric push rod, a screw module, etc. The linear displacement mechanism 3331 is mounted on the centering frame plate 34. The first end of the push rod 3332 is pivotally connected to the displacement output end of the linear displacement mechanism 3331. The second end of the push rod 3332 is restricted to slide in the slide groove 3322. A spring 3333 is provided between the second end of the push rod 3332 and the bottom wall of the slide groove 3322. The two ends of the spring 3333 are respectively in contact with the second end of the push rod 3332 and the bottom wall of the slide groove 3322. The spring 3333 acts as a buffer to reduce hard impact during movement, thereby making the position adjustment process of the wafer 10 smoother.

[0064] In some embodiments, as Figure 1 、 Figure 9 and Figure 10 As shown, the wafer pre-alignment device may further include an information reading device 6, and the main frame 1 and / or the centering mechanism 3 may have at least a through area 7 which is not blocked in the upper and lower directions (see Figure 3 、 Figure 4 、 Figure 5 and Figure 9 ), with the reading end of the information reader 6 facing the through-area 7. The information reader 6 is mounted on the main frame 1 and positioned below the through-area 7, with the reading end of the information reader 6 facing the through-area 7. The rotation mechanism 2 drives the wafer to rotate so that the identity information identification code on the back of the wafer faces the through-area 7. The information reader 6 is used to read the identity information identification code on the back of the wafer through the through-area 7.

[0065] The information reading device 6 can be a camera, which is mounted on a motion module (not shown in the figure). The position of the camera is adjusted by controlling the operation of the motion module to more conveniently acquire images of the back side of the wafer. The identity information identification code on the back side of the wafer is equivalent to the identity code of the wafer. The wafer can be identified by this identity code, and the pre-alignment information can be bound to the identity code to facilitate subsequent processes.

[0066] In some embodiments, as Figure 8 、 Figure 9 and Figure 10As shown, the rotating mechanism 2 includes a rotary power unit 22, a rotating shaft 23, and a pneumatic connector 24. The rotating shaft 23 is mounted on the rotating power unit 22, which drives the rotating shaft 23 to rotate. A suction cup 21 is mounted on the top of the rotating shaft 23, which is connected to the pneumatic connector 24. An air path is provided within the rotating shaft 23, connecting the pneumatic connector 24 to the support surface 211 of the suction cup 21. The starter connector 24 is connected to a vacuum generator via a pipeline. An electrically controlled valve is provided on the connecting pipeline, which is controlled by a controller to generate or lose negative pressure on the support surface 211.

[0067] In some embodiments, as Figure 1 and Figure 3 As shown, the wafer pre-alignment device may further include a buffer assembly 8, which includes a buffer frame 81 and a presence detection sensor 82. The buffer frame 81 is mounted on the main frame 1 and is provided with multiple receiving areas for accommodating wafers of different sizes. Pre-aligned wafers can be temporarily placed in the receiving areas of the buffer frame 81. A presence detection sensor 82 is mounted in the middle of the buffer frame 81 to detect whether a wafer is accommodated on the buffer frame 81.

[0068] In some embodiments, as Figures 1 to 3 As shown, the wafer pre-alignment apparatus may further include a cleaning assembly, which includes at least a cleaning nozzle 9 disposed above the suction cup 21, with the output end of the cleaning nozzle 9 facing the suction cup 21. The cleaning nozzle 9 may be tilted to achieve a better purge effect. The primary function of the cleaning nozzle 9 is to purge the wafer placed on the suction cup 21, removing any dust particles and other particles that may be present, thereby maintaining the cleanliness of the wafer surface.

[0069] The embodiment of the present application also provides a semiconductor device (not shown in the figure), including the aforementioned wafer pre-alignment device, and an equipment base can be set at a predetermined position on the semiconductor device, and the main frame 1 of the wafer pre-alignment device can be installed on the equipment base. The semiconductor device can also include a conveying device, a gripping device, a detection device, etc. For example, the wafer to be detected can be transported by a conveying device to a location close to the wafer pre-alignment device, and then the gripping device can grip the wafer and place it on the wafer pre-alignment device for pre-alignment. After the pre-alignment is completed, the same gripping device or other gripping devices can place the pre-aligned wafer into the detection device for detection.

[0070] The present application also provides a pre-alignment method of the aforementioned wafer pre-alignment device, comprising:

[0071] S1, placing the wafer on the carrying surface 211 of the suction cup 21, and controlling the carrying surface 211 to maintain a non-negative pressure state;

[0072] S2, the centering mechanism 3 drives the wafer placed on the suction cup 21 to adjust its position until the center of the wafer coincides with the center of the carrying surface 211, and then the centering mechanism 3 is out of contact with the wafer;

[0073] S3, controlling the carrying surface 211 of the suction cup 21 to generate negative pressure to absorb the wafer;

[0074] S4, controlling the suction cup 21 of the rotating mechanism 2 to rotate to drive the wafer to rotate, and identifying the vacant area at the edge of the wafer through the alignment sensor 5;

[0075] S5, determining the current azimuth angle of the wafer by aligning the information of the vacant area on the edge of the wafer identified by the sensor 5;

[0076] S6. Control the suction cup 21 of the rotating mechanism 2 to rotate to adjust the azimuth angle of the wafer. When the azimuth angle of the wafer is adjusted to a desired angle, the pre-alignment process of the wafer is completed.

[0077] The foregoing description is merely a partial list of preferred embodiments of the present application and is not intended to limit the present application. Persons skilled in the art will readily appreciate that various modifications and variations are possible. Any modifications, equivalent substitutions, or improvements made within the spirit and principles of the present application shall be included within the scope of protection of the present application.

Claims

1. A wafer pre-alignment device, characterized in that: include: Main frame (1); A rotating mechanism (2) is mounted on the main frame (1), comprising a rotatable suction cup (21), the rotation axis of which is along the Z direction, the upper surface of the suction cup (21) being configured as a bearing surface (211) having a negative pressure adsorption capability, and the rotation axis passing through the center of the bearing surface (211); a centering mechanism (3), mounted on the main frame (1), configured to drive the position of a wafer placed on the suction cup (21) to adjust so that the center of the wafer coincides with the center of the carrying surface (211); An alignment component comprises a reflecting portion (4) and an alignment sensor (5), wherein the reflecting portion (4) is arranged below the carrying surface (211), the alignment sensor (5) is mounted above the carrying surface (211), and the alignment sensor (5) faces the reflecting portion (4); After the center of the wafer coincides with the center of the carrying surface (211), and when the suction cup (21) absorbs the wafer and rotates to a predetermined angle, the light beam path between the alignment sensor (5) and the reflecting part (4) passes through the vacant area at the edge of the wafer.

2. The wafer pre-alignment device according to claim 1, wherein: The centering mechanism (3) comprises at least two centering members (31) capable of moving toward and away from each other, and the centering members (31) are arc-shaped; The suction cup (21) of the rotating mechanism (2) is located between the centering members (31), and the rotation axis coincides with the center of the area surrounded by the centering members (31); Wherein, when all the centering members (31) move toward each other until the wafer on the suction cup (21) is clamped, the center of the wafer coincides with the center of the carrying surface (211).

3. The wafer pre-alignment device according to claim 2, wherein: Each centering member (31) is provided with at least two steps (311) of different heights and at different distances from the suction cup (21); the steps (311) are arc-shaped, and the step (311) on the side away from the suction cup (21) is higher than the step (311) on the side close to the suction cup (21); The diameter of the circular area enclosed by the arc sidewalls of the steps (311) where the plurality of centering members (31) are at the same height is adapted to the diameter of the corresponding wafer; The centering mechanism (3) includes a centering drive device (33) and a lifting device (32); the lifting device (32) is mounted on the main frame (1), the centering drive device (33) is mounted on the lifting device (32), and the centering drive device (33) is connected to the centering member (31); The lifting device (32) is used to drive all the centering members (31) to rise or fall simultaneously, so that the sidewalls of the steps (311) in the centering members (31) that are adapted to the diameter of the corresponding wafer are at the same height as the wafer; The centering drive device (33) is used to drive the centering members (31) to move toward or away from each other simultaneously.

4. The wafer pre-alignment device according to claim 3, wherein: The side walls of the steps (311) of the centering members (31) at different heights form a plurality of circular areas with different diameters, an alignment sensor (5) is mounted above the edge of each circular area, and a corresponding reflector (4) is provided on a predetermined structural surface below the corresponding bearing surface (211) of each alignment sensor (5).

5. The wafer pre-alignment device according to claim 3, wherein: The centering mechanism (3) includes a horizontally arranged centering frame plate (34), and the displacement output end of the lifting device (32) is connected to the centering frame plate (34); The centering drive device (33) comprises a track (331), a turntable (332), and a power assembly (333); a plurality of the tracks (331) are mounted on the upper surface of the centering frame plate (34) and are arranged around the center of the suction cup (21), and each track (331) extends radially along the suction cup (21); a centering member (31) is slidably mounted on each track (331); The turntable (332) is located below the suction cup (21) and is rotatably mounted on the centering frame plate (34), and the rotation axis of the turntable (332) coincides with the rotation axis of the suction cup (21); The rotating disk (332) is provided with at least the same number of arcuate grooves (3321) as the number of the centering members (31); the arcuate grooves (3321) are eccentrically arranged and evenly distributed around the central circumference of the rotating disk (332); the center of the arcuate grooves (3321) does not coincide with the center of the rotating disk (332); A cylindrical member (312) is provided on the centering member (31) and is inserted into the arc-shaped groove (3321), and the cylindrical member (312) is restricted from moving in the arc-shaped groove (3321); The power assembly (333) is mounted on the centering frame plate (34) and is used to drive the turntable (332) to rotate.

6. The wafer pre-alignment device according to claim 5, characterized in that: The power assembly (333) includes a linear displacement mechanism (3331), a push rod (3332) and a spring (3333); a slide groove (3322) is provided on the turntable (332); The linear displacement mechanism (3331) is installed on the centering frame plate (34), the first end of the push rod (3332) is pivotally connected to the displacement output end of the linear displacement mechanism (3331), the second end of the push rod (3332) is restricted to slide in the slide groove (3322), and the spring (3333) is arranged between the second end of the push rod (3332) and the bottom wall of the slide groove (3322), and the two ends of the spring (3333) are respectively kept in contact with the second end of the push rod (3332) and the bottom wall of the slide groove (3322).

7. The wafer pre-alignment device according to any one of claims 1 to 6, characterized in that: The wafer pre-alignment device further comprises an information reading device (6); the main frame (1) and / or the centering mechanism (3) at least reserve a through area (7) that is unobstructed in the upper and lower directions; and a reading end of the information reading device (6) faces the through area (7); The information reading device (6) is installed on the main frame (1) and is located below the through-hole area (7), with the reading end of the information reading device (6) facing the through-hole area (7); The rotating mechanism (2) drives the wafer to rotate so that the identity information identification code on the back of the wafer faces the through-area (7); The information reading device (6) is used to read the identity information identification code on the back side of the wafer through the through area (7).

8. The wafer pre-alignment device according to any one of claims 1 to 6, characterized in that: The rotating mechanism (2) further comprises a rotating power device (22), a rotating shaft (23) and a pneumatic joint (24); The rotating shaft (23) is mounted on the rotating power device (22), and the rotating power device (22) is used to drive the rotating shaft (23) to rotate. The suction cup (21) is mounted on the top of the rotating shaft (23), and the top is connected to the pneumatic joint (24); An air path is provided inside the rotating shaft (23) for connecting the pneumatic joint (24) with the bearing surface (211) of the suction cup (21).

9. The wafer pre-alignment device according to any one of claims 1 to 6, characterized in that: The wafer pre-alignment device further comprises a cache component (8), which comprises a cache frame (81) and an in-situ detection sensor (82); The buffer frame (81) is mounted on the main frame (1), and a plurality of accommodating areas for accommodating wafers of different sizes are provided on the buffer frame (81); The in-situ detection sensor (82) is installed at the middle position of the buffer frame (81) and is used to detect whether a wafer is accommodated on the buffer frame (81).

10. The wafer pre-alignment device according to any one of claims 1 to 6, characterized in that: The wafer pre-alignment device further comprises a cleaning component, which comprises a cleaning nozzle (9) arranged above the suction cup (21), and an output end of the cleaning nozzle (9) faces the suction cup (21).

11. A semiconductor device, characterized in that: The method comprises the wafer pre-alignment device according to any one of claims 1 to 10.

12. A pre-alignment method for a wafer pre-alignment device according to any one of claims 1 to 10, characterized in that: include: Placing the wafer on the carrying surface (211) of the suction cup (21), and controlling the carrying surface (211) to maintain a non-negative pressure state; The centering mechanism (3) drives the wafer placed on the suction cup (21) to adjust its position until the center of the wafer coincides with the center of the carrying surface (211), and then the centering mechanism (3) is released from contact with the wafer; Controlling the bearing surface (211) of the suction cup (21) to generate negative pressure to absorb the wafer; Controlling the rotation of the suction cup (21) of the rotating mechanism (2) to drive the wafer to rotate, and identifying the vacant area at the edge of the wafer through the alignment sensor (5); Determining the current azimuth angle of the wafer by aligning information of the vacant area on the edge of the wafer identified by the sensor (5); The suction cup (21) of the rotating mechanism (2) is controlled to rotate to adjust the azimuth angle of the wafer. When the azimuth angle of the wafer is adjusted to a desired angle, the pre-alignment process of the wafer is completed.

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