Self-rotation type wafer moving device capable of moving in multiple dimensions

Abstract

The utility model discloses a self-rotation type wafer moving device capable of moving in multiple dimensions, which comprises a lifting mechanism, a mechanical arm rotating mechanism, a tray self-rotation mechanism, a vacuum cavity, a reaction unit and a wafer frame, the mechanical arm rotating mechanism and the tray self-rotation mechanism are both arranged in the vacuum cavity, the tray self-rotation mechanism is fixed on the mechanical arm rotating mechanism, and the tray self-rotation mechanism is fixed on the vacuum cavity. The wafer rack is mounted above the tray spinning mechanism, and the reaction unit is mounted at the top of the vacuum cavity; the mechanical arm rotating mechanism comprises a tray, a lifting shaft and a power device installed at the top of the lifting shaft, the tray is installed in the vacuum cavity, the tray self-rotating mechanism is installed at the top of the tray, the lifting shaft is installed at the end, away from the tray self-rotating mechanism, of the tray, the lifting mechanism is installed at the top of the vacuum cavity, and the lifting mechanism is rotationally connected with the lifting shaft. The problems that an existing wafer moving device is insufficient in precision and stability and not high in speed and efficiency are solved.

Description

Technical Field

[0001] This utility model relates to the field of semiconductor equipment manufacturing technology, and in particular to a self-rotating wafer motion device capable of multi-dimensional movement. Background Technology

[0002] Low-pressure chemical vapor deposition (LP-CVD) plays a crucial role in semiconductor manufacturing technology. It utilizes chemical reactions at specific temperatures and pressures to form desired thin film materials on a substrate. This technology is not only applied to silicon wafers but can also be extended to other types of substrates to build complex and high-performance semiconductor devices. The application of vacuum technology is particularly critical for precisely controlling the uniformity and quality of the thin film. In a vacuum environment, interference from impurities and gas molecules can be significantly reduced, ensuring the stability and repeatability of the deposition process. Furthermore, vacuum technology allows for precise control of parameters such as temperature, pressure, and gas flow rate during the reaction process, providing the necessary conditions for high-quality thin film deposition.

[0003] In these advanced vacuum devices, the wafer motion mechanism is the key component for achieving precise movement and positioning. It typically consists of a sophisticated mechanical structure, drive system, and control system, capable of precisely controlling the wafer's position and orientation at the micrometer or even nanometer level. This allows the wafer to be accurately aligned with each processing station, ensuring the uniformity and consistency of thin film deposition.

[0004] The design and manufacturing process of wafer motion devices is also extremely challenging. To meet the high precision requirements of semiconductor manufacturing, advanced materials, precise processing techniques, and stringent quality control measures are necessary. Furthermore, with the continuous development of semiconductor technology, wafer motion devices also require constant technological upgrades and innovations to adapt to higher processing precision and more complex process requirements.

[0005] Current technical challenges include: Precision and stability: With the continuous advancement of semiconductor technology, the demand for smaller, more integrated chips is increasing. Simultaneously, the precision and stability of wafer movement devices pose a significant technical challenge. Speed ​​and efficiency: As processes become increasingly complex, the number and complexity of moving workstations also increase. Therefore, handling large-scale, highly complex wafers requires more efficient movement and positioning mechanisms. Utility Model Content

[0006] The purpose of this invention is to provide a self-rotating wafer motion device capable of multi-dimensional motion, in order to solve the problems mentioned in the background art.

[0007] The above-mentioned technical objective of this utility model is achieved through the following technical solution:

[0008] A multi-dimensional rotating wafer motion device includes a lifting mechanism, a robotic arm rotation mechanism, a tray spinning mechanism, a vacuum chamber, a reaction unit, and a wafer rack. The robotic arm rotation mechanism and the tray spinning mechanism are both installed inside the vacuum chamber. The tray spinning mechanism is fixed to the robotic arm rotation mechanism. The wafer rack is installed above the tray spinning mechanism. The reaction unit is installed on the top of the vacuum chamber. The top of the vacuum chamber has a through hole corresponding to the wafer rack, and the bottom opening of the reaction unit corresponds to the through hole. The robotic arm rotation mechanism includes a tray, a lifting shaft, and a power unit installed on top of the lifting shaft. The tray is installed inside the vacuum chamber, the tray spinning mechanism is installed on top of the tray, the lifting shaft is installed at the end of the tray away from the tray spinning mechanism, and the lifting mechanism is installed on top of the vacuum chamber. The lifting mechanism is rotatably connected to the lifting shaft.

[0009] Preferably, the lifting mechanism includes a sliding assembly, a ball bearing, a ball screw, and a lifting shaft support frame. The ball bearing is mounted on the sliding assembly and sleeved on the lifting shaft. The lifting shaft support frame is mounted on the top of the vacuum chamber. The ball screw is rotatably mounted on the lifting shaft support frame, with both ends of the ball screw mounted on two slide rails. Both slide rails are mounted on the lifting shaft support frame. The sliding assembly is slidably mounted on the two slide rails and the ball screw. The sliding assembly and the ball screw are threadedly engaged. A lifting shaft coupling support frame is also mounted at the bottom of the lifting shaft support frame. The bottom of the ball screw passes through the lifting shaft support frame and is fixed with a lifting shaft coupling. A lifting shaft reducer is mounted at the bottom of the lifting shaft coupling support frame. The output shaft of the lifting shaft reducer is connected to the lifting shaft coupling. A lifting shaft motor is also mounted at the bottom of the lifting shaft reducer. A drag chain is also provided on the sliding assembly.

[0010] Preferably, the power unit includes a rotating arm motor, a rotating arm coupling, a rotating arm support, and a rotating arm reducer. The rotating arm coupling is fixed to the top of the lifting shaft, the rotating arm support is installed on the top of the sliding assembly, the rotating arm coupling is disposed inside the rotating arm support, the rotating arm reducer is installed above the rotating arm support, the output shaft of the rotating arm reducer is connected to the rotating arm coupling, the rotating arm motor is installed above the rotating arm reducer, and the rotating arm motor is connected to the rotating arm reducer.

[0011] Preferably, the tray rotation mechanism includes a sealing tray, a tray base, a rotation drive system, and a rotating tray. The tray base is fixed to the top of the tray, the sealing tray is installed on the upper end of the tray base, the rotation drive system is installed on the inner top wall of the tray base, the sealing tray is installed on the upper end of the tray base, and the bottom of the rotating tray is provided with a central shaft. The rotating tray is rotatably connected to the sealing tray through the central shaft, and the central shaft passes through the sealing tray and is connected to the rotation drive system.

[0012] Preferably, both the lifting shaft and the tray seat are hollow structures, and the inner cavity of the lifting shaft communicates with the inner cavity of the tray seat.

[0013] Preferably, the reaction unit includes a heater, an injection pipe, and an air inlet flange. The reaction unit is a heater, which has an outer reaction chamber and an inner reaction chamber inside. The injection pipe is installed in the inner reaction chamber, and the air inlet flange is installed at the bottom of the heater. The injection pipe is fixed on the air inlet flange.

[0014] Beneficial effects: The combination of lifting and rotating mechanisms increases the range and dimensions of wafer movement, thereby improving the efficiency and precision of the wafer motion device and enabling its application in more complex wafer coating equipment. The hollow structure of the lifting shaft and tray base not only ensures stable operation but also greatly facilitates wiring and maintenance. Furthermore, the hollow structure helps reduce heat buildup inside the equipment, improving overall performance and stability. The robotic arm's rotating mechanism allows for movement not only vertically but also horizontally (80° to 100°), meeting more complex process requirements and further enhancing the efficiency and precision of the wafer motion device, making it suitable for more sophisticated wafer coating equipment. Attached Figure Description

[0015] Figure 1 This is an analytical diagram illustrating the operation of the self-rotating wafer motion device of this application.

[0016] Figure 2 This is an analytical diagram of the lifting mechanism of the self-rotating wafer motion device of this application.

[0017] Figure 3 This is an analytical diagram of the robotic arm rotation mechanism of the self-rotating wafer motion device of this application.

[0018] Figure 4 This is an analytical diagram of the tray spinning mechanism of the self-rotating wafer motion device of this application.

[0019] Figure 5 This is an analytical cross-sectional view of the lifting shaft cavity and tray support cavity of the self-rotating wafer motion device of this application.

[0020] Figure 6 This is an analytical cross-sectional view of the reaction unit of the self-rotating wafer motion device of this application.

[0021] Reference numerals: 1. Lifting mechanism; 2. Robotic arm rotation mechanism; 3. Pallet spin mechanism; 4. Vacuum chamber; 5. Reaction unit; 6. Wafer rack; 101. Sliding assembly; 102. Ball bearing; 103. Lifting shaft; 104. Ball screw; 105. Lifting shaft support frame; 106. Slide rail; 107. Lifting shaft coupling; 108. Lifting shaft coupling support frame; 109. Lifting shaft reducer; 110. Lifting shaft motor; 111. Cable chain; 201. Rotating arm motor; 202. Rotating arm coupling; 203. Rotating arm support seat; 204. Rotating arm reducer; 301. Sealed pallet; 302. Pallet seat; 303. Rotation drive system; 304. Rotating pallet; 501. Heater; 502. Outer reaction chamber; 503. Inner reaction chamber; 504. Injection pipe; 505. Inlet flange. Detailed Implementation

[0022] See Figures 1 to 6 As shown, a multi-dimensional rotating wafer motion device includes a lifting mechanism 1, a robotic arm rotation mechanism 2, a tray spin mechanism 3, a vacuum chamber 4, a reaction unit 5, and a wafer carrier 6. The robotic arm rotation mechanism 2 and the tray spin mechanism 3 are both installed inside the vacuum chamber 4. The tray spin mechanism 3 is fixed on the robotic arm rotation mechanism 2. The wafer carrier 6 is installed above the tray spin mechanism 3. The reaction unit 5 is installed on the top of the vacuum chamber 4. The top of the vacuum chamber 4 has a through hole corresponding to the wafer carrier 6. The bottom opening of the reaction unit 5 corresponds to the through hole.

[0023] The robotic arm rotation mechanism 2 includes a tray, a lifting shaft 103, and a power unit mounted on top of the lifting shaft 103. The tray is installed inside the vacuum chamber 4, the tray rotation mechanism 3 is installed on top of the tray, the lifting shaft 103 is installed at the end of the tray away from the tray rotation mechanism 3, and the lifting mechanism 1 is installed on top of the vacuum chamber 4. The lifting mechanism 1 is rotatably connected to the lifting shaft 103. When it is necessary to load the wafer, the robotic arm rotation mechanism 2 can be started first. The robotic arm rotation mechanism 2 causes the tray rotation mechanism 3 and the wafer rack 6 to rotate clockwise, which facilitates the loading of the wafer. When the tray rotation mechanism 3 needs to rotate, the power unit can be started first. The power unit drives the lifting shaft 103 to rotate, and the lifting shaft 103 drives the tray rotation mechanism 3 and the wafer rack 6 to rotate.

[0024] The power unit includes a rotating arm motor 201, a rotating arm coupling 202, a rotating arm support 203, and a rotating arm reducer 204. The rotating arm coupling 202 is fixed to the top of the lifting shaft 103. The rotating arm support 203 is installed on the top of the sliding assembly 101. The rotating arm coupling 202 is located inside the rotating arm support 203. The rotating arm reducer 204 is installed above the rotating arm support 203. The output shaft of the rotating arm reducer 204 is connected to the rotating arm coupling 202. The rotating arm motor 201 is installed above the rotating arm reducer 204 and is connected to the rotating arm reducer 204. When it is necessary to drive the lifting shaft 103 to rotate, the rotating arm motor 201 can be started first. The rotating arm motor 201 will drive the rotating arm reducer 204 to rotate, which in turn drives the rotating arm coupling 202 to rotate. The rotating arm coupling 202 can drive the lifting shaft 103 to rotate. Under the action of this drive system, the position and orientation of the wafer can be adjusted quickly and accurately, meeting the stringent requirements of high precision and high response speed for wafer movement in semiconductor manufacturing processes, and effectively improving production efficiency and product quality.

[0025] After the wafer is mounted, the lifting mechanism 1 can be activated. The lifting mechanism 1 drives the lifting shaft 103 to achieve height adjustment. The lifting shaft 103 can drive the tray rotation mechanism 3 and the wafer holder 6 into the reaction unit 5 for heating treatment. The lifting mechanism 1 includes a sliding component 101, a ball bearing 102, a ball screw 104, and a lifting shaft support frame 105. The ball bearing 102 is mounted on the sliding component 101 and sleeved on the lifting shaft 103. The lifting shaft support frame 105 is installed in a vacuum... At the top of cavity 4, a ball screw 104 is rotatably mounted on a lifting shaft support frame 105. Both ends of the ball screw 104 are respectively mounted on two slide rails 106, both of which are mounted on the lifting shaft support frame 105. A sliding assembly 101 is slidably mounted on the two slide rails 106 and the ball screw 104, and the sliding assembly 101 is threadedly engaged with the ball screw 104. A lifting shaft coupling support frame 108 is also mounted at the bottom of the lifting shaft support frame 105, with the bottom of the ball screw 104 passing through the lifting shaft support frame 105. 5. A lifting shaft coupling 107 is fixedly installed. A lifting shaft reducer 109 is installed at the bottom of the lifting shaft coupling support frame 108. The output shaft of the lifting shaft reducer 109 is connected to the lifting shaft coupling 107. A lifting shaft motor 110 is also installed at the bottom of the lifting shaft reducer 109. A drag chain 111 is also provided on the sliding assembly 101. When it is necessary to drive the lifting shaft 103 to lift, the lifting shaft 103 motor can be started first, and the lifting shaft reducer 109 will be driven by the lifting shaft motor 110. The reducer 109 drives the ball screw 104 to rotate. During rotation, the ball screw 104 drives the sliding component 101 to slide on the slide rail 106. The lifting shaft 103 is connected to the sliding component 101 via a ball bearing 102. The ball bearing 102 prevents the lifting shaft 103 from rotating along with the sliding component 101. The lifting shaft 103 drives the tray spinning mechanism 3 and the wafer holder 6 into the reaction chamber. With such high precision and stable operating performance, this technology effectively improves the uniformity of the thin film in the thin film deposition process, effectively controls the film thickness deviation, shortens the process time, and greatly improves production efficiency and product quality.

[0026] The reaction unit 5 includes a heater 501, an injection pipe 504, and an inlet flange 505. The heater 501 is the main component, containing an outer reaction chamber 502 and an inner reaction chamber 503. The injection pipe 504 is installed inside the inner reaction chamber 503, and the inlet flange 505 is installed at the bottom of the heater 501. The injection pipe 504 is fixed to the inlet flange 505. When the wafer enters the reaction unit 5, the heater 501 operates, heating the outer reaction chamber 502 and the inner reaction chamber 503. The precursor is injected into the chambers through the injection pipe 504, thereby achieving thin film deposition and growth. The flow rate of the injection pipe 504 can be precisely controlled to ensure the accuracy of the precursor injection amount. Under these reaction conditions, the thin film deposition rate is improved, the thickness deviation of the deposited thin film is further reduced, significantly improving the quality and uniformity of the thin film, and effectively enhancing the performance and yield of semiconductor devices.

[0027] The tray rotation mechanism 3 includes a sealed tray 301, a tray base 302, a rotation drive system 303, and a rotating tray 304. The tray base 302 is fixed to the top of the tray, the sealed tray 301 is installed on the upper end of the tray base 302, the rotation drive system 303 is installed on the inner top wall of the tray base 302, and the bottom of the rotating tray 304 is provided with a central shaft. The rotating tray 304 is rotatably connected to the sealed tray 301 through the central shaft. The central shaft passes through the sealed tray 301 and is connected to the rotation drive system 303. When the lifting shaft 103 drives the tray... When the tray spin mechanism 3 is raised and lowered, the sealing tray 301 of the tray spin mechanism 3 continuously moves and cooperates with the bottom of the reaction unit 5 to seal the bottom of the reaction unit 5. The rotating tray 304 is located inside the reaction unit 5. In order to improve the reaction efficiency of the wafer, the spin drive system 303 can be activated. The spin drive system 303 can be a drive motor. The spin drive system drives the central shaft to rotate, the central shaft drives the rotating tray 304 to rotate, and the rotating tray 304 drives the wafer holder 6 and the wafer to rotate. After the spin drive system is activated, the average reaction time of the wafer is shortened, the reaction uniformity is further improved, the thickness deviation of the thin film deposition is further reduced, and the reaction quality and production efficiency are significantly improved.

[0028] Both the lifting shaft 103 and the pallet seat 302 are hollow structures. The inner cavity of the lifting shaft 103 communicates with the inner cavity of the pallet seat 302. The wiring in the pallet spinning mechanism 3 is arranged in the pallet cavity and the lifting shaft 103 cavity and leads to the outside of the vacuum chamber 4, and then is collected and organized inside the cable chain 111. Regarding equipment stability, because the wiring is neatly housed within the hollow structure, it avoids entanglement or collision with other components during equipment movement, thereby reducing equipment failures caused by wiring problems and lowering the equipment failure rate compared to traditional designs. In terms of maintenance convenience, the clear wiring arrangement allows maintenance personnel to quickly locate and troubleshoot wiring faults, greatly shortening maintenance time. Furthermore, the hollow structure also has excellent heat dissipation performance, accelerating the dissipation of heat inside the equipment, lowering the internal temperature, effectively ensuring stable operation and extending the equipment's service life.

[0029] Working principle:

[0030] During loading: Driven by the rotary arm drive system (rotary arm coupling 202, rotary arm motor 201 and rotary arm reducer 204), the robotic arm rotation mechanism 2 rotates clockwise 80° to 100° to cooperate with the loading and unloading gate. When the loading work begins, the gate of the vacuum chamber 4 opens, and the robotic arm extends into the vacuum chamber 4 from the interface with the gate to start loading the wafer rack 6. For each wafer loaded, the lifting drive system (lifting shaft coupling 107, lifting shaft motor 110 and lifting shaft reducer 109) drives the lifting shaft 103 to rise one unit height to cooperate with the loading until the loading is completed.

[0031] Before the process begins: the robotic arm rotation mechanism 2 is driven to rotate counterclockwise back to directly below the reaction unit 5 by the rotary drive system (rotary arm coupling 202, rotary arm motor 201 and rotary arm reducer 204); the sliding component 101 is driven to move vertically upward by the lifting drive system (lifting shaft coupling 107, lifting shaft motor 110 and lifting shaft reducer 109), which drives the lifting shaft 103 to slide upward in the ball bearing 102, thereby driving the robotic arm rotation mechanism 2 and the wafer holder 6 to be lifted upward until the upper surface of the sealing tray 301 is lifted to abut against the inner surface of the reaction unit 5, the wafer holder 6 is completely inserted into the reaction unit 5, and the reaction unit 5 is sealed.

[0032] After the process begins: the heater 501 starts working, heating the outer reaction chamber 502 and the inner reaction chamber 503. The precursor is injected into the chamber through the injection pipe 504 to achieve thin film deposition and growth.

[0033] During the process: Temperature rises and purge gas begins within reaction unit 5. The self-rotating drive system 303 starts operating, driving the rotating tray 304 to rotate, which in turn drives the wafer rack 6 to rotate within reaction unit 5, resulting in more uniform heating. During the process, the sealing tray 301 does not rotate, maintaining a constant seal.

[0034] After the process is completed: the self-rotation drive system 303 stops working, the rotating tray 304 stops rotating, and the wafer rack 6 also stops rotating. The lifting drive system (lifting shaft coupling 107, lifting shaft motor 110 and lifting shaft reducer 109) drives the sliding mechanism to return downward to the vacuum chamber 4. Under the drive of the rotating arm drive system 2 (rotating arm coupling 202, rotating arm motor 201 and rotating arm reducer 204), the robotic arm rotating mechanism 2 rotates clockwise 80° to 100°, the door of the vacuum chamber 4 opens, and the robotic arm reaches in through the door to take out the wafer. For each unit of wafer taken out, the lifting drive system moves downward by one unit until it is completely removed, completing the unloading task of the coated wafer.

[0035] Through the seamless coordination of a series of components, this device successfully automates the wafer loading and unloading process. No direct human intervention is required throughout the entire wafer loading, unloading, and processing stages. This not only significantly improves work efficiency but also effectively avoids the safety risks and potential contamination problems that may arise from manual operation.

Claims

1. A multi-dimensional rotating wafer motion device, comprising a lifting mechanism (1), a robotic arm rotation mechanism (2), a tray rotation mechanism (3), a vacuum chamber (4), a reaction unit (5), and a wafer rack (6), characterized in that, The robotic arm rotation mechanism (2) and the tray spin mechanism are both installed inside the vacuum chamber (4). The tray spin mechanism (3) is fixed on the robotic arm rotation mechanism (2). The wafer rack (6) is installed above the tray spin mechanism (3). The reaction unit (5) is installed on the top of the vacuum chamber (4). The top of the vacuum chamber (4) has a through hole corresponding to the wafer rack (6). The bottom opening of the reaction unit (5) corresponds to the through hole. The robotic arm rotation mechanism (2) includes a tray, a lifting shaft (103), and a power device installed on the top of the lifting shaft (103). The tray is installed inside the vacuum chamber (4). The tray spin mechanism (3) is installed on the top of the tray. The lifting shaft (103) is installed at the end of the tray away from the tray spin mechanism (3). The lifting mechanism (1) is installed on the top of the vacuum chamber (4). The lifting mechanism (1) is rotatably connected to the lifting shaft (103).

2. The multi-dimensional rotating wafer motion device according to claim 1, characterized in that, The lifting mechanism (1) includes a sliding assembly (101), a ball bearing (102), a ball screw (104), and a lifting shaft support frame (105). The ball bearing (102) is mounted on the sliding assembly (101) and sleeved on the lifting shaft (103). The lifting shaft support frame (105) is mounted on the top of the vacuum chamber (4). The ball screw (104) is rotatably mounted on the lifting shaft support frame (105). The two ends of the ball screw (104) are respectively mounted on two slide rails (106). Both slide rails (106) are mounted on the lifting shaft support frame (105). The sliding assembly (101) is slidably mounted on the two slide rails (101, 102, 104, 105, 106, 107, 108, 109, 1000, 1000, 101, 1000, 1000, 101, 1000, 101, 1000, 101, 102, 103, 104, and 105. 6) On the ball screw (104), the sliding assembly (101) is threadedly engaged with the ball screw (104). The bottom of the lifting shaft support frame (105) is also equipped with a lifting shaft coupling support frame (108). The bottom of the ball screw (104) passes through the lifting shaft support frame (105) and is fixed with a lifting shaft coupling (107). The bottom of the lifting shaft coupling support frame (108) is equipped with a lifting shaft reducer (109). The output shaft of the lifting shaft reducer (109) is connected to the lifting shaft coupling (107). The bottom of the lifting shaft reducer (109) is also equipped with a lifting shaft motor (110). The sliding assembly (101) is also equipped with a drag chain (111).

3. The multi-dimensional rotating wafer motion device according to claim 2, characterized in that, The power unit includes a rotating arm motor (201), a rotating arm coupling (202), a rotating arm support (203), and a rotating arm reducer (204). The rotating arm coupling (202) is fixed to the top of the lifting shaft (103). The rotating arm support (203) is installed on the top of the sliding assembly (101). The rotating arm coupling (202) is located inside the rotating arm support (203). The rotating arm reducer (204) is installed above the rotating arm support (203). The output shaft of the rotating arm reducer (204) is connected to the rotating arm coupling (202). The rotating arm motor (201) is installed above the rotating arm reducer (204) and is connected to the rotating arm reducer (204).

4. The multi-dimensional rotating wafer motion device according to claim 1, characterized in that, The tray rotation mechanism (3) includes a sealing tray (301), a tray base (302), a rotation drive system (303), and a rotating tray (304). The tray base (302) is fixed to the top of the tray. The sealing tray (301) is installed on the upper end of the tray base (302). The rotation drive system (303) is installed on the inner top wall of the tray base (302). The bottom of the rotating tray (304) is provided with a central shaft. The rotating tray (304) is rotatably connected to the sealing tray (301) through the central shaft. The central shaft passes through the sealing tray (301) and is connected to the rotation drive system (303).

5. A multi-dimensional rotating wafer motion device according to claim 4, characterized in that, Both the lifting shaft (103) and the tray seat (302) are hollow structures, and the inner cavity of the lifting shaft (103) communicates with the inner cavity of the tray seat (302).

6. The multi-dimensional rotating wafer motion device according to claim 1, characterized in that, The reaction unit (5) includes a heater (501), an injection pipe, and an air inlet flange (505). The reaction unit (5) is a heater (501). The heater (501) has an outer reaction chamber (502) and an inner reaction chamber (503) inside. The injection pipe (504) is installed in the inner reaction chamber (503). The air inlet flange (505) is installed at the bottom of the heater (501). The injection pipe (504) is fixed on the air inlet flange (505).

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