A wafer transport system and semiconductor device

Abstract

This invention provides a wafer transport system and semiconductor device. The wafer transport system includes a buffer stage, several pressure detection units for detecting wafer weight, a photoelectric detection unit, and a pickup unit disposed above the buffer stage. The pickup unit includes two parallel rotating gripping plates. At least one side of each rotating gripping plate along its extension direction forms a fixed fork tooth portion that supports the wafer edge and has a first notch. Two connecting arms are connected to the ends of the rotating gripping plates. The pickup unit determines the axial rotation angle of the rotating gripping plates based on detection signals sent by the photoelectric detection units and the pressure detection units. The wafer transport system disclosed in this application avoids defects such as wafer drop or fragmentation that may occur during wafer gripping and transport, and enables clamping operations on wafers of different thicknesses, improving the reliability of wafer clamping operations.

Description

Technical Field

[0001] This invention relates to the field of semiconductor equipment technology, and more particularly to a wafer transport system and semiconductor equipment. Background Technology

[0002] Wafer Transfer Systems (WTS) are primarily used for batch wafer transfer in diffusion furnaces and bench wet cleaners. A typical WTS system can handle 25 wafers at a time. In some semiconductor manufacturing processes, the back side of the wafer needs to be polished. After the back side polishing process is completed, the WTS system is generally used to transfer the wafers to a wafer cleaning unit for the cleaning process.

[0003] The WTS (Wafer Buffer Station) system includes a wafer buffer station and a robotic arm. The wafer buffer station primarily serves as a transfer or temporary storage station for wafers, often used for contamination prevention and isolation of wafers before and after processing, or for consolidation and integration devices transporting more than 25 wafers. Wafer buffer stations are generally placed vertically or horizontally. The maximum number of slots can be any number, but must be at least one, depending on the equipment size or process requirements. Vertical placement is typically used in the manufacturing of 8-inch and smaller wafers.

[0004] In existing WTS (Wafer Transfer System) robotic arms, the end effector structure is fixed and lacks size adjustment capabilities. This leads to variations in wafer thickness and weight within the same wafer storage area after different processing steps. In particular, the weight of wafers thinned by grinding or etching differs significantly from that of unthinned wafers. When this difference exceeds the maximum servo capability of the fixed end effector of the robotic arm, it can result in risks such as wafer drop or fragmentation during the WTS's wafer gripping and transport process.

[0005] In view of this, it is necessary to improve the existing wafer transfer system to solve the above problems. Summary of the Invention

[0006] The purpose of this invention is to disclose a wafer transport system and a semiconductor device based on the wafer transport system, in order to solve the defects such as wafer drop or fragmentation that may occur in the traditional wafer transport system during the wafer gripping and transport process, to realize the clamping operation of wafers of different thicknesses, and to improve the reliability of the wafer transport system in performing wafer clamping operations.

[0007] To achieve the first objective mentioned above, the present invention provides a wafer transport system, comprising:

[0008] The buffer stage includes several pressure detection units, photoelectric detection units, and pickup units located above it for detecting wafer weight.

[0009] The pickup unit includes two parallel rotating grippers. Each rotating gripper has a fixed fork tooth portion with a first notch forming a support for the wafer edge along at least one side along its extension direction. The pickup unit determines the axial rotation angle of the rotating grippers based on the detection signals sent by the photoelectric detection unit and the pressure detection unit.

[0010] As a further improvement of the present invention, the pressure detection unit includes:

[0011] The main body has support bases at both ends and built-in pressure sensors. The top of the support base has a notch for receiving the edge of the wafer. The pressure detection unit is thin and parallel to each other. The pressure sensor independently collects the weight data of each wafer placed on the pressure sensor and sends it to the pickup unit.

[0012] As a further improvement of the present invention, the photoelectric detection unit includes: at least one detection plate, wherein a plurality of photoelectric sensors are arranged linearly at intervals along one side of the detection plate.

[0013] As a further improvement to the present invention, it also includes:

[0014] Optical detection unit;

[0015] The optical detection unit includes a first servo system that moves along the wafer thickness direction and an imaging unit. The imaging unit is controlled by the first servo system and performs longitudinal movement to sequentially acquire thickness data of each wafer and send the thickness data to the pickup unit.

[0016] As a further improvement of the present invention, the two parallel sides of the rotating gripping plate are respectively formed with fixed fork teeth, and the opening size of the fixed fork teeth on the two sides is the same or different.

[0017] As a further improvement of the present invention, the picking unit further includes:

[0018] The system comprises two parallel connecting arms, two rotating shafts, and mounting bases. The two connecting arms are connected by the two rotating shafts, and each rotating shaft is equipped with a mounting base. The rotating gripping plate is fixedly connected to the mounting base.

[0019] At least two second servo mechanisms for driving the rotating shaft are disposed at the free end of the connecting arm;

[0020] The second servo mechanism drives the rotating shaft to rotate, which in turn drives the rotating gripper to flip in opposite directions, so as to support the bottom edge of the wafer through the fixed fork with the first notch.

[0021] As a further improvement of the present invention, the pickup unit further includes: at least one row of movable fork teeth and a drive mechanism for driving the movable fork teeth to perform telescopic movement;

[0022] The movable fork tooth has a second notch with an opening size different from the first notch, and the opening direction of the second notch is configured in the same direction as the opening direction of the first notch; the second servo mechanism drives the rotating shaft to rotate, and drives the rotating gripper plate to flip synchronously in opposite directions, so as to support the bottom edge of the wafer through the first notch of the fixed fork tooth or the second notch of the movable fork tooth.

[0023] As a further improvement of the present invention, the picking unit includes two rows of movable fork teeth arranged on the fixed fork teeth portion, the two rows of movable fork teeth being arranged on the same side or two opposite different sides of the rotating gripping plate. Based on the same inventive concept, this application also discloses a semiconductor device, including:

[0024] Semiconductor equipment front-end modules; and

[0025] A wafer transport system as described in any of the preceding inventions, located in the front-end module of the semiconductor device;

[0026] The semiconductor device is at least a semiconductor device that performs a diffusion process, a semiconductor device that performs a chemical mechanical polishing process, a semiconductor device that performs a tank cleaning process, or a semiconductor device that performs a wet etching process.

[0027] Compared with the prior art, the beneficial effects of the present invention are:

[0028] In this application, at least through a pressure detection unit and a photoelectric detection unit, real-time and efficient detection of the thinned wafer is achieved, and the detection data of different thicknesses or weights are sent to the pickup unit with a rotating gripper plate. The fixed or movable fork teeth set by the rotating gripper plate support the edge of the wafer, thereby effectively avoiding defects such as wafer drop or fragmentation that may occur during the wafer transfer system's gripping and transfer of wafers. This enables clamping operations on wafers of different thicknesses, thereby improving the reliability of the wafer transfer system in clamping wafers. Attached Figure Description

[0029] Figure 1 This is a perspective view of a wafer transmission system according to the present invention, which includes a photoelectric detection unit and a pressure detection unit.

[0030] Figure 2This is a schematic diagram of an optical detection unit included in a wafer transport system of the present invention detecting several wafers arranged in a vertical state to obtain thickness data of each wafer.

[0031] Figure 3 for Figure 2 A three-dimensional view of a single pressure sensing unit is shown;

[0032] Figure 4 This is a perspective view of a pickup unit in a wafer transport system according to the present invention;

[0033] Figure 5 This is a front view of a rotating gripper included in the pickup unit;

[0034] Figure 6 for Figure 5 A magnified view of the area indicated by the middle arrow M;

[0035] Figure 7 for Figure 5 A magnified view of the area indicated by the middle arrow N;

[0036] Figure 8 for Figure 5 A 3D view of the rotating gripper in the image;

[0037] Figure 9 for Figure 8 A magnified view of the area indicated by the middle arrow C;

[0038] Figure 10 for Figure 8 A magnified view of the area indicated by the middle arrow D;

[0039] Figure 11 This diagram illustrates the process of transferring a raised wafer by rotating two symmetrically arranged rotating grippers in a pickup unit. The dashed circles represent wafers that have not yet risen, while the solid circles represent wafers that have risen and are held up by the two rotating grippers.

[0040] Figure 12 This is a side view of a modified version of the rotating gripper.

[0041] Figure 13 This is a side view of a modified version of the rotating gripper. Detailed Implementation

[0042] The present invention will now be described in detail with reference to the embodiments shown in the accompanying drawings. However, it should be noted that these embodiments are not intended to limit the present invention. Equivalent changes or substitutions in function, method, or structure made by those skilled in the art based on these embodiments are all within the scope of protection of the present invention.

[0043] In the description of the present invention, it should be understood that the orientation or positional relationship indicated by the terms "center", "longitudinal", "transverse", "length", "width", "thickness", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", "clockwise", "counterclockwise", "axial", "radial", "circumferential", "positive direction", "negative direction", etc. are based on the orientation or positional relationship shown in the drawings, and are only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be construed as a limitation to the present invention.

[0044] Example 1:

[0045] Refer Figures 1 to 11 The first specific embodiment of a wafer transfer system of the present invention disclosed.

[0046] In this embodiment, a wafer transfer system includes: a buffer table 34, a plurality of pressure detection units 35 for detecting the weight of the wafer disposed above the buffer table 34, a photoelectric detection unit, and a picking unit. The picking unit includes two rotatable gripping plates 40 arranged in parallel. At least one side edge of the rotatable gripping plate 40 along its extending direction forms a fixed fork tooth portion 42 for supporting the edge of the wafer and having a first notch 420. The picking unit determines the axial rotation angle of the rotatable gripping plate 40 to be the rotation angle formed in the direction indicated by the arrow B along the Figure 4 central axis A. Preferably, the picking unit further includes: at least one row of movable fork teeth and a driving mechanism for driving the movable fork teeth to perform telescopic movement.

[0047] Specifically, the rotation direction of the rotatable gripping plate 40 can be clockwise or counterclockwise, but the two rotatable gripping plates 40 must be guaranteed to rotate synchronously and oppositely, and when the two rotatable gripping plates 40 are in a vertical state, the horizontal linear distance formed between the two rotatable gripping plates 40 must be greater than the diameter of the wafer 50.

[0048] Refer Figure 1As shown, the photoelectric detection unit includes at least one detection plate 49, with a plurality of photoelectric sensors 491 arranged linearly at intervals along one side of the plate. The detection plate 49 can move up and down under the control of an external servo mechanism (not shown). When a portion of the wafer 50 (typically the horizontal edge of a vertically arranged wafer 50) blocks the light emitted between the linearly spaced photoelectric sensors 491 (e.g., infrared light), the photoelectric sensors 491 send an enable signal or a high-level signal to a host computer (e.g., a PLC controller, an industrial computer, or a device with an independent logic unit), thereby determining whether the wafer 50 placed on the pressure detection unit 35 has a missing part or its position deviates from the normal preset position.

[0049] In practical applications, the photoelectric detection unit can consist of two parallel detection plates 49. In this case, photoelectric sensors 491, arranged at linear intervals, are positioned on the opposing inner sides of the two detection plates 49, with the spacing between the detection plates 49 greater than the diameter of the wafer 50 to be measured. Simultaneously, it must be ensured that when the photoelectric detection unit moves vertically up and down, a portion of the edge of the wafer 50 can pass over the photoelectric sensor 491, allowing the wafer 50 to be detected by the photoelectric sensor 491. It should be noted that in this embodiment, the photoelectric detection unit can also consist of only one detection plate 49.

[0050] Figure 1 and Figure 3 As shown, the pressure detection unit 35 includes: a body 351, and support bases 352 disposed at both ends of the body 351 and housing pressure sensors. The top of the support base 352 has a notch 3521 for receiving the edge of the wafer. The pressure detection unit 35 is sheet-shaped and parallel to each other. The pressure sensors independently collect the weight data of each wafer 50 placed on the support base 352 and send it to the pickup unit (see Figure 1). Figure 4 (As shown). A gap 354 is formed between two adjacent pressure detection units 35. The number of vertically arranged pressure detection units 35 configured on the main body 351 can be determined according to the actual application scenario, and is preferably twenty-five or fifty.

[0051] In this embodiment, the body 351 is disposed inside the semiconductor device. The notch 3521 extends along... Figure 4The (lateral) width formed along the central axis A is at least greater than the thickness of wafer 50 to reliably accommodate the edge of wafer 50. Multiple pressure detection units 35 are arranged in a parallel and dense manner on the buffer stage 34. Each pressure detection unit 35 is connected to a host computer via an independent wire 353. The host computer determines the thickness of a wafer 50 of a specific size based on the detection signals containing the weight data of wafer 50 independently sent by all pressure detection units 35. Since the thickness and weight of wafers 50 of six-inch, eight-inch, and larger sizes have a relatively fixed relationship, the thickness data of each wafer 50 can be calculated based on the weight data of each wafer 50 vertically placed on multiple pressure detection units 35 and sent to the appropriate unit. Figure 4 The picking unit shown is not described in detail in this embodiment, given that the relationship and conversion method between wafer weight and thickness are mature existing technologies.

[0052] Combination Figure 2 As shown, in this embodiment, the wafer transfer system further includes an optical detection unit 30. The optical detection unit 30 includes a first servo system that moves along the wafer thickness direction and an imaging unit 33. The imaging unit 33 is controlled by the first servo system and performs longitudinal movement to sequentially acquire thickness data of each wafer 50 and send the thickness data to the pickup unit. The longitudinal movement direction performed by the imaging unit 33 is... Figure 4 The axis A is shown in the diagram. The first servo system consists of a frame 30, a guide rod 31 transversely placed on the frame 30, and a sliding seat 32 that reciprocates on the guide rod 31 and has a built-in power mechanism. The power mechanism can be a micro servo motor or a micro stepper motor. The power mechanism can drive the sliding seat 32 to make longitudinal linear motion on the guide rod 31 as a whole through belt drive or gear mechanism.

[0053] Simultaneously, the imaging unit 33 captures images of each wafer 50 individually to obtain thickness data for each wafer 50, and then sends this thickness data to the host computer. Since the thickness of the wafer 50 after thinning is significantly reduced compared to the thickness of a normal wafer (0.725mm), the thickness data of each wafer 50 is monitored online in real time. This provides accurate detection results (i.e., thickness and weight data for each wafer) for selecting appropriate fixed or movable forks on the sides of the two rotating grippers 40 of the pickup unit to support the edges of the wafer 50. The imaging unit 33 can be composed of a high-precision image sensor, such as a CMOS or CCD chip and an optical lens.

[0054] It should be noted, in particular, that the wafer transport system shown in this embodiment may omit the optical detection unit.

[0055] Meanwhile, during the various semiconductor processes that the wafer 50 undergoes, the thickness of the wafer 50 may also change due to film deposition processes, epitaxial layer processes, wafer bonding processes (Wafer Bonding), etc. Even the thicknesses of the wafers 50 in the same Lot may be different. Therefore, the wafer transfer system disclosed in this embodiment, especially the pick-up unit included in the wafer transfer system, aims to achieve reliable grasping of wafers 50 with different thicknesses and prevent risks such as wafer dropping or breaking during the process of the pick-up unit grasping and transferring the wafer 50 to the wafer buffer station (Buffer Station).

[0056] Refer Figure 4 to Figure 5 As shown, on two parallel sides of the rotary grasping plate 40 in the pick-up unit, fixed fork tooth portions 42 are respectively formed, and the opening sizes of the fixed fork tooth portions 42 on the two sides may be the same or different. Here, the opening size is the opening width and / or the opening radial depth of the first notch 420 of the fixed fork tooth portion 42 and the second notches 433, 453 of the movable fork teeth. After receiving detection signals such as the weight data of each wafer 50 and whether there is a missing wafer 50, the host computer sends them to the host computer, and the host computer calculates the detection results of the number of wafers 50 and the thickness. Then, according to the foregoing detection results, the pick-up unit drives the two rotary grasping plates 40 to rotate synchronously and oppositely by the second servo mechanism 24 for the rotating shaft 22 to determine which fixed fork tooth portion 42 formed by which side of the rotary grasping plate 40 supports the bottom edge of the wafer 50. During the process of handling wafers 50 with different thicknesses (or weights), fixed fork tooth portions 42 with different opening sizes are provided on the two sides to efficiently grasp and transfer wafers 50 with different thicknesses (or weights).

[0057] Refer Figure 4 As shown, in this embodiment, the pick-up unit further includes: two parallel connecting arms 10, two rotating shafts 22, and a mounting base 21. The two connecting arms are connected by the two rotating shafts 22, and a mounting base 21 is arranged on each rotating shaft 22. The rotary grasping plate 40 is fixedly connected to the mounting base 21, and at least two second servo mechanisms 24 for driving the rotating shaft 22 are provided at the free ends of the connecting arms 10. The second servo mechanism 24 drives the rotating shaft 22 to rotate, driving the rotary grasping plates 40 to flip synchronously and oppositely to support the bottom edge of the wafer 50 through the fixed fork tooth portions. The second servo mechanism 24 drives the rotating shaft 22 to integrally drive the mounting base 21 and the rotary grasping plate 40 to pivot within a set rotation angle range along the rotation direction shown by arrow B in the axial direction shown by axis A.

[0058] In a further preferred embodiment, the mounting base 21 is detachably assembled with the rotating gripper plate 40 to facilitate the replacement of rotating gripper plates 40 with different opening sizes of the fixed fork tooth portion 42, thereby better adapting to the gripping operation of wafers 50 of different sizes and specifications. The connecting arms 10 are respectively located at the lateral ends of the two parallel rotating shafts 22.

[0059] Combination Figures 5 to 11 As shown, in this embodiment, the picking unit further includes: at least one row of movable fork teeth and a driving mechanism for driving the movable fork teeth to perform telescopic movement. The movable fork teeth have second notches 433 and 453 with different opening sizes than the first notch 420. The opening directions of the second notches 433 and 453 are arranged in the same direction as the opening direction of the first notch 420. Specifically, the driving mechanism can be a cylinder. The second servo mechanism 24 drives the rotating shaft to rotate, driving the rotating gripper plate 40 to flip synchronously in opposite directions, so as to support the bottom edge of the wafer 50 through the fixed fork tooth portion 42 or the movable fork teeth.

[0060] Optionally, the picking unit includes two rows of movable forks disposed on the fixed fork portion 42, and the two rows of movable forks are disposed on the same side of the rotating gripping plate 40.

[0061] More specifically, refer to Figure 5 , Figure 9 and Figure 10 As shown, each rotating gripper 40 includes a rectangular planar base plate 41, with fixed fork teeth 42 formed on each of its two sides. A connector 421 and a connector 411 are provided on one side of the base plate 41. One set of cylinders 45 is fixedly mounted on the connector 421, and each cylinder 45 is connected to a movable fork tooth 452 with a second notch 453 via a telescopic rod 451. The end of the movable fork tooth 452 forms a second notch 453 for supporting the edge of the wafer 50. Simultaneously, another set of cylinders 43 is fixedly mounted on the connector 411, and each cylinder 43 is connected to a movable fork tooth 432 with a second notch 433 via a telescopic rod 431. The end of the movable fork tooth 432 forms a second notch 433 for supporting the edge of the wafer 50. The edges of multiple parallel wafers 50 are jointly inserted and clamped by the second notch 433 (or second notch 453) formed by the side region 200 of the substrate 41 and the fixed fork tooth 42 or the movable fork tooth 432 (or the movable fork tooth 452) in the region 300. Each cylinder in each row of cylinders 45 or each row of cylinders 43 in the rotating gripping plate 40 can independently perform a telescopic movement.

[0062] Combination Figure 5 , Figure 9 and Figure 10 As shown, in this embodiment, the cylinder 45 independently drives the movable fork tooth 452 to extend to... Figure 9As shown in the diagram, the movable fork tooth 452a is in a state where the cylinder 43 independently drives the movable fork tooth 432 to extend to... Figure 10 The state shown is that the movable fork tooth 432a is in which the edge of the wafer 50 is clamped by one or more movable fork teeth 452a and one or more movable fork teeth 432a, or by one or more movable fork teeth 452a and the fixed fork tooth part 42 on the other side, or the edge of the wafer 50 is clamped by the two fixed fork teeth 42 on the side without extending the cylinder.

[0063] As a reasonable variation of this embodiment, a fixed fork tooth portion 42 supporting the wafer edge can also be formed only on one side of the rotating gripper plate 40. The second servo mechanism 24 drives the rotating shaft 22 to rotate the rotating gripper plate 40, and uses the fixed fork tooth portions 42 configured on the two rotating gripper plates 40 to support the edge of the wafer 50.

[0064] Combination Figure 6 As shown, in this embodiment, the second notch 453 formed at the end of the movable fork tooth 452 has the same opening direction as the first notch 420 formed by the fixed fork tooth portion 42. The opening angle α of the first notch 420 is greater than the opening angle β of the second notch 453, so that the edge of the thinned wafer 50 can be clamped by the second notch 453 formed by the two movable fork teeth 452. Each cylinder 45 can be pushed or stretched individually, thereby driving one or more movable fork teeth 452 to extend or retract individually, so as to reasonably select the first notch 420 or the second notch 453 to clamp the edge of the wafer 50. In this embodiment, a longitudinal distance is formed between two adjacent movable fork teeth 452 (along... Figure 4 The gap is 455 (d2 in the direction where the central axis A is located).

[0065] Combination Figure 7As shown, in this embodiment, the second notch 433 formed at the end of the movable fork tooth 432 has the same opening direction as the first notch 420 formed by the fixed fork tooth portion 42 on the other side. The opening angle α of the first notch 420 is greater than the opening angle β of the second notch 433, so that the edge of the thinned wafer 50 can be clamped by the second notch 433 formed by the two movable fork teeth 452. Each cylinder 45 can be pushed or stretched individually, thereby driving one or more movable fork teeth 452 to extend or retract individually, so as to reasonably select the first notch 420 or the second notch 433 to clamp the edge of the wafer 50. In this embodiment, the fixed fork tooth portion 42 formed on the other side forms a gap 435 with a spacing of d1, and the number of movable fork teeth 432 configured in region 300 is half the number of movable fork teeth 452 configured in region 200, so that the maximum number of wafers 50 gripped by the wafer transport system can be fifty and twenty-five respectively, so as to meet the actual needs of different semiconductor process technologies. In particular, it should be noted that the opening size of the first notch 420 can be set to be smaller than the opening size of the second notch 433 (or the second notch 453), so that the wafer 50 with increased thickness can be clamped by the rotating gripper plate 40.

[0066] Based on the aforementioned detection results including weight and thickness data, the host computer selects a suitable fork tooth from the fixed fork tooth section 42 or movable fork tooth section with different opening sizes on the rotating gripper plate 40, and the second servo mechanism 24 synchronously drives the two rotating shafts 22 to rotate, thereby synchronously driving the two rotating gripper plates 40 to pivot along axis A and in the direction indicated by arrow B, so that the suitable fork tooth supports the lower edge of the wafer 50. Then, the selected fixed fork tooth section 42, which is most suitable for the thickness of the current wafer 50, supports the lower edge of the wafer 50 and lifts multiple wafers 50 as a whole. Specifically, the buffer stage 34 is controlled to move upward, so as to move the wafer 50, which is placed vertically on the pressure detection unit 35, from position 50a to the preset intermediate position 50b. At this time, the two rotating gripper plates 40 are at position 40a as shown by the dotted line. Then, the two rotating gripper plates 40 are synchronously rotated in opposite directions (see reference). Figure 11in the direction indicated by arrow B), so that the selected and appropriate fork tooth openings on the two rotary gripping plates 40 face each other. Then, control the buffer table 34 to move downward, so as to drive the wafer 50 placed vertically on the pressure detection unit 35 to move downward to the said appropriate fork teeth to catch the wafer 50, thereby realizing the gripping of the wafer 50 that has been placed vertically on the pressure detection unit 35 by the pickup unit and transporting it to a cleaning tank (not shown) of a semiconductor device to perform a semiconductor process of wet etching or acid cleaning. Preferably, when the two rotary gripping plates 40 are in a vertical state, the distance between them is greater than the diameter of the wafer, and the two rotary gripping plates 40 remain vertical or substantially vertical during the upward movement of the wafer 50 to avoid touching and damaging the wafer 50. Drive the rotary gripping plate 40 to rotate by the second servo mechanism 24, and make the two rotary gripping plates 40 pivot in the reverse direction indicated by arrow B to a vertical posture, and then lift the pickup unit as a whole to release the wafer 50. In this embodiment, the buffer table 34 can perform translational movement, upward movement and downward movement through a guide rail, a cylinder and a servo mechanism in the prior art.

[0067] Finally, in this embodiment, two side edges of the rotary gripping plate along its extending direction form fixed fork tooth portions that support the wafer edge and have the same opening size, that is, the opening sizes of the first notches 420 of the fixed fork tooth portions on the two side edges are the same. Of course, two side edges of the rotary gripping plate along its extending direction can also form fixed fork tooth portions that support the wafer edge and have different opening sizes.

[0068] Based on the wafer transfer system disclosed in this embodiment, it solves the problem that the single opening size of the fixed fork tooth portions for clamping the wafer edge provided on the two side edges of a flat rotary gripping plate 40 cannot effectively meet the clamping requirements of wafers with different thicknesses. It can adapt to the scenarios where the thickness of the wafer 50 increases or decreases or different wafers 50 in the same Lot have different thicknesses, and perform gripping and transfer operations on the wafer 50, thereby more effectively improving the reliability of the wafer transfer system disclosed in this embodiment for clamping the wafer 50 and preventing the wafer 50 from dropping during the clamping process due to changes in thickness.

[0069] Example 2:

[0070] Refer Figure 12 As shown, this embodiment discloses another specific implementation manner of a wafer transfer system. The main difference between this embodiment and the wafer transfer system disclosed in Embodiment 1 is that, in this embodiment, the pickup unit includes two rows of movable fork teeth arranged on the fixed fork tooth portions, and the two rows of movable fork teeth are arranged on two opposite and different sides of the rotary gripping plate 40.

[0071] Specifically, in this embodiment, the movable fork teeth 45a and the movable fork teeth 43a are respectively located on two opposite and different sides of the substrate 41a, and can drive the movable fork teeth 45a and the movable fork teeth 43a to extend or retract respectively along the directions shown by the arrow D and the arrow D' according to the actual thickness data of the wafer 50, so as to select the first notch 420 or the second notch 433 (or the second notch 453) with the opening size that best matches the thickness of the wafer 50.

[0072] In actual use, the second servo mechanism 24 can be used to drive the rotation shaft 22 to rotate, and drive the rotary gripper plate 40 to flip in opposite directions synchronously, so as to support the bottom edge of the wafer 50 together by any fixed fork tooth part or movable fork teeth on the side that best adapts to the thickness of the wafer 50, so as to clamp and grab the wafer 50 together.

[0073] The wafer transfer system shown in this embodiment has the same technical solutions as the wafer transfer system shown in Embodiment 1. Please refer to Embodiment 1 for details and will not be elaborated here.

[0074] Example 3:

[0075] Refer Figure 13 As shown, this embodiment discloses another specific implementation of a wafer transfer system. The main difference between the wafer transfer system disclosed in this embodiment and the wafer transfer system disclosed in Embodiment 2 is that in this embodiment, the pickup unit includes a row of movable fork teeth arranged on the fixed fork tooth part.

[0076] Specifically, in this embodiment, the movable fork teeth 45a are respectively located on any one side of the substrate 41b, and can drive the movable fork teeth 45a to extend or retract respectively along the direction shown by the arrow D according to the actual thickness data of the wafer 50, so as to select the first notch 420 or the second notch 433 with the opening size that best matches the thickness of the wafer 50 to support the bottom edge of the wafer 50 together, so as to clamp and grab the wafer 50 together.

[0077] The wafer transfer system shown in this embodiment has the same technical solutions as the wafer transfer system shown in Embodiment 1 and / or Embodiment 2. Please refer to Embodiment 1 and / or Embodiment 2 for details and will not be elaborated here.

[0078] Example 4:

[0079] Based on the technical solutions included in a wafer transfer system disclosed in Embodiments 1 to 3, this embodiment also discloses a semiconductor device, including:

[0080] A semiconductor device front-end module; and a wafer transport system as disclosed in Embodiment 1 disposed in the semiconductor device front-end module. The wafer transport system can be configured in the semiconductor device front-end module (EFEM) or in a wafer transport scenario.

[0081] The semiconductor equipment shown in this embodiment is at least a semiconductor equipment performing a diffusion process, a semiconductor equipment performing a chemical mechanical polishing process, a semiconductor equipment performing a tank cleaning process, or a semiconductor equipment performing a wet etching process. Since the thickness and weight of the wafer can vary significantly during diffusion, chemical mechanical polishing, tank cleaning, or wet etching processes, using a wafer transport system combining any one or more of the embodiments in Embodiments 1 to 3 can significantly improve the reliability of wafer transport and clamping processes, preventing wafer drop and breakage.

[0082] The semiconductor device shown in this embodiment has the same technical solutions as those in Embodiments 1 to 3. Please refer to Embodiments 1 to 3 for details, which will not be repeated here.

[0083] The detailed descriptions listed above are merely specific descriptions of feasible embodiments of the present invention, and are not intended to limit the scope of protection of the present invention. All equivalent embodiments or modifications made without departing from the spirit of the present invention should be included within the scope of protection of the present invention.

[0084] It will be apparent to those skilled in the art that the present invention is not limited to the details of the exemplary embodiments described above, and that the invention can be implemented in other specific forms without departing from its spirit or essential characteristics. Therefore, the embodiments should be considered in all respects as exemplary and non-limiting, and the scope of the invention is defined by the appended claims rather than the foregoing description. Thus, all variations falling within the meaning and scope of equivalents of the claims are intended to be included within the present invention. No reference numerals in the claims should be construed as limiting the scope of the claims.

[0085] Furthermore, it should be understood that although this specification describes embodiments, not every embodiment contains only one independent technical solution. This narrative style is merely for clarity. Those skilled in the art should consider the specification as a whole, and the technical solutions in each embodiment can also be appropriately combined to form other embodiments that can be understood by those skilled in the art.

Claims

1. A wafer transmission system, characterized in that, include: The buffer stage includes several pressure detection units, photoelectric detection units, and pickup units located above it for detecting wafer weight. The pickup unit includes two parallel rotating grippers that rotate synchronously in opposite directions. Each gripper has two sides along its extending direction that form fixed fork teeth that support the bottom edge of the wafer and have first notches with different opening sizes. The pickup unit determines the axial rotation angle of the rotating grippers based on detection signals sent by a photoelectric detection unit and a pressure detection unit. The pickup unit also includes two parallel connecting arms, two rotating shafts, a mounting base, at least one row of movable fork teeth, and a drive mechanism for driving the movable fork teeth to extend and retract. The two connecting arms are connected by the two rotating shafts. The assembly consists of a mounting base on each of the rotating shafts, a rotating gripper plate fixedly connected to the mounting base, and at least two second servo mechanisms for driving the rotating shafts located at the free end of the connecting arm. The movable fork tooth has a second notch with an opening size different from the first notch, and the opening direction of the second notch is the same as the opening direction of the first notch. The second servo mechanism drives the rotating shaft to rotate, and drives the rotating gripper plate to rotate synchronously in opposite directions, so as to support the bottom edge of the wafer through the first notch of the fixed fork tooth or the second notch of the movable fork tooth.

2. The wafer transport system according to claim 1, characterized in that, The pressure detection unit includes: The main body has support bases at both ends and built-in pressure sensors. The top of the support base has a notch for receiving the edge of the wafer. The pressure detection unit is thin and parallel to each other. The pressure sensor independently collects the weight data of each wafer placed on the pressure sensor and sends it to the pickup unit.

3. The wafer transport system according to claim 1, characterized in that, The photoelectric detection unit includes at least one detection plate, wherein a plurality of photoelectric sensors are arranged in a linearly spaced manner along one side of the detection plate.

4. The wafer transport system according to claim 1, characterized in that, Also includes: Optical detection unit; The optical detection unit includes a first servo system that moves along the wafer thickness direction and an imaging unit. The imaging unit is controlled by the first servo system and performs longitudinal movement to sequentially acquire thickness data of each wafer and send the thickness data to the pickup unit.

5. The wafer transport system according to any one of claims 1 to 4, characterized in that, The picking unit includes two rows of movable fork teeth arranged on the fixed fork teeth section. The two rows of movable fork teeth are arranged on the same side or two opposite sides of the rotating gripping plate.

6. A semiconductor device, characterized in that, include: Semiconductor equipment front-end module; as well as A wafer transport system as described in any one of claims 1 to 5, located in the front-end module of the semiconductor device; The semiconductor device is at least a semiconductor device that performs a diffusion process, a semiconductor device that performs a chemical mechanical polishing process, a semiconductor device that performs a tank cleaning process, or a semiconductor device that performs a wet etching process.

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