Epitaxial apparatus wafer transfer device

Abstract

The application discloses an epitaxial equipment wafer conveying device, which comprises a device body and a vacuum cavity arranged on the device body, wherein the device body is provided with a clean space, the clean space is provided with a taking and placing component, a first wafer box and a second wafer box; the vacuum cavity is used for growing an epitaxial layer and is provided with a door valve; the vacuum cavity is arranged on one side of the clean space and is communicated with or interrupted with the clean space through the opening and closing of the door valve; the first wafer box is used for storing wafers before reaction; the second wafer box is used for storing wafers after reaction; the taking and placing component is used for taking the wafers in the first wafer box and placing the wafers in the vacuum cavity, and then taking the wafers after reaction from the vacuum cavity and placing the wafers in the second wafer box. The epitaxial equipment wafer conveying device can make the wafer conveying process in the clean space, avoid the influence of air disturbance, avoid the contamination of the wafer surface by impurities, ensure that the quality of the epitaxial layer meets the standard, and has the advantages of simple structure and convenient operation.

Description

Technical Field

[0001] The present invention relates to the technical field of semiconductor equipment, and in particular to a wafer transfer device for epitaxial equipment. Background Art

[0002] In an epitaxial process, not only an epitaxial layer with a lattice structure completely consistent with that of a substrate needs to be grown on the surface of the substrate, but also the epitaxial layer needs to be doped to form a P-type or N-type active layer. The epitaxial process needs to be performed at high temperature, and measures such as heat preservation and heat insulation are taken to ensure the smooth progress of the process. To ensure that the quality of the epitaxial layer meets the standard, the wafer transfer environment needs to meet the requirements of high cleanliness and no air disturbance.

[0003] Existing wafer transfer devices have the following problems:

[0004] 1. The transfer process of wafers before and after reaction is exposed to the external environment, which is easily affected by air disturbance in the environment, so that the wafer surface is contaminated by impurities, which directly affects the quality of the epitaxial layer.

[0005] 2. The unreasonable layout of wafer storage components, vacuum chambers and pick-and-place components results in a cumbersome transfer process and inconvenient operation. Summary of the Invention

[0006] The technical problem to be solved by the present invention is to overcome the deficiencies of the prior art and provide a wafer transfer device for epitaxial equipment that prevents the wafer transfer process from being affected by air disturbance and avoids impurity contamination on the wafer surface.

[0007] To solve the above technical problem, the present invention adopts the following technical solution:

[0008] A wafer transfer device for epitaxial equipment comprises a device body and a vacuum chamber arranged on the device body, wherein a clean space is arranged on the device body, and a pick-and-place component, a first wafer cassette and a second wafer cassette are arranged in the clean space; the vacuum chamber is used for growing an epitaxial layer and provided with a gate valve, the vacuum chamber is arranged on one side of the clean space, and communication or disconnection between the vacuum chamber and the clean space is realized through opening and closing of the gate valve; the first wafer cassette is used for storing unreacted wafers; the second wafer cassette is used for storing reacted wafers; the pick-and-place component is used for taking out wafers from the first wafer cassette and placing the wafers into the vacuum chamber, and then taking out the reacted wafers from the vacuum chamber and placing the reacted wafers into the second wafer cassette.

[0009] As a further improvement of the above technical solution: the first wafer cassette and the second wafer cassette are both arranged on a wafer cassette support base and located on opposite sides corresponding to the pick-and-place component, and the vacuum chamber, the first wafer cassette and the second wafer cassette are arranged in a delta-shaped layout.

[0010] As a further improvement to the above technical solution: the device body is provided with a door panel for opening or closing the clean space, one side of the door panel is hinged to the device body through a hinge lock, and the other side is connected to the device body through an electromagnetic lock.

[0011] As a further improvement to the above technical solution: the door panel is provided with a limiting piece, the limiting piece is provided with a limiting hole, and the electromagnetic lock is provided with a locking shaft that can extend into the limiting hole.

[0012] As a further improvement to the above technical solution: the electromagnetic lock comprises an electromagnetic coil, a shaft sleeve and a first spring, the shaft sleeve is penetrated in the electromagnetic coil and sleeved outside the locking shaft, and the first spring is arranged between the shaft sleeve and the locking shaft and is used for enabling the locking shaft to extend into the limiting hole.

[0013] As a further improvement to the above technical solution: the end of the locking shaft is provided with a flange portion, and the limiting piece is provided with a bending portion.

[0014] As a further improvement to the above technical solution: the device body is provided with a spring seat, the spring seat is provided with a pushing block and a second spring, the second spring is arranged between the spring seat and the pushing block and is used for pushing the pushing block out to abut against the closed door panel.

[0015] As a further improvement to the above technical solution: the pick-and-place component comprises a manipulator, the manipulator is provided with a clean finger, and the clean finger is provided with a negative pressure suction port.

[0016] As a further improvement to the above technical solution: a wafer finder for detecting appearance defects of wafers is also arranged in the clean space.

[0017] As a further improvement to the above technical solution: a tray is arranged in the vacuum cavity, and the tray is provided with a groove for reducing the adsorption force between the tray and a wafer.

[0018] Compared with the prior art, the beneficial effects of the present invention are:

[0019] 1. The wafer transfer device of epitaxial equipment disclosed by the present invention enables the transfer process of wafers to be in a clean space, avoids being affected by air disturbance, thereby preventing the wafer surface from being contaminated by impurities, ensures that the quality of an epitaxial layer meets the standard, and has a simple structure and convenient operation.

[0020] 2. The wafer transfer device of epitaxial equipment disclosed by the present invention further adopts a "triangular" layout for the vacuum cavity, the first cassette and the second cassette, which has a reasonable layout and makes the transfer process simple and convenient. Description of the Drawings

[0021] Figure 1This is a three-dimensional structural diagram of the wafer transfer device for epitaxial equipment according to the present invention.

[0022] Figure 2 This is a schematic diagram of the internal structure of the wafer transfer device in the epitaxial equipment of the present invention.

[0023] Figure 3 This is a schematic diagram of the structure of the chip holder support in a specific application example of the present invention.

[0024] Figure 4 This is a schematic diagram of the edge finder and clean fingers in a specific application example of the present invention.

[0025] Figure 5 This is a schematic diagram of the tray structure in a specific application example of the present invention.

[0026] Figure 6 This is a schematic diagram of the door panel connection relationship in a specific application example of the present invention.

[0027] Figure 7 for Figure 6 A partial schematic diagram of point A in the middle.

[0028] Figure 8 This is a cross-sectional view of the electromagnetic lock in a specific application example of the present invention.

[0029] Figure 9 This is a cross-sectional view of the spring seat in a specific application example of the present invention.

[0030] Legend:

[0031] 1. Device body; 11. Mounting plate; 12. Spring seat; 13. Push block; 14. Second spring; 2. Vacuum chamber; 21. Door valve; 22. Tray; 221. Groove; 222. Second clearance groove; 3. Picking and placing components; 31. Robotic arm; 311. Cleaning finger; 312. Negative pressure suction port; 313. First clearance groove; 4. First wafer cassette; 5. Second wafer cassette; 6. Wafer cassette support; 61. Photoelectric sensor; 62. Wafer cassette limiting block; 7. Door panel; 71. Hinge lock; 72. Electromagnetic lock; 721. Electromagnetic coil; 722. Bushing; 723. Locking shaft; 724. First spring; 725. Flange; 726. Limiting nut; 73. Limiting piece; 731. Limiting hole; 732. Bending part; 8. Edge finder; 9. Wafer. Detailed Implementation

[0032] The present invention will be further described in detail below with reference to the accompanying drawings and specific embodiments.

[0033] As shown in this disclosure and the claims, unless the context clearly indicates otherwise, the words "a," "an," "an," and / or "the" are not specifically singular and may include plural forms. The terms "first," "second," and similar terms used in this disclosure do not indicate any order, quantity, or importance, but are merely used to distinguish different components. Similarly, the terms "comprising" or "including" mean that the element or object preceding the word covers the element or object listed after the word and its equivalents, without excluding other elements or objects. The terms "connected" or "linked" are not limited to physical or mechanical connections but may include electrical connections, whether direct or indirect.

[0034] Figures 1 to 9 An embodiment of the present invention is shown. The epitaxial wafer transfer device of this embodiment includes a device body 1 and a vacuum cavity 2 disposed on the device body 1. The device body 1 is provided with a clean space, and the clean space is provided with a pick-and-place component 3, a first wafer cassette 4 and a second wafer cassette 5.

[0035] The vacuum chamber 2 is used to grow epitaxial layers and is equipped with a gate valve 21. The vacuum chamber 2 is located on one side of the clean space and is connected to or disconnected from the clean space by opening and closing the gate valve 21.

[0036] The first box 4 is used to store the wafer 9 before the reaction;

[0037] The second box 5 is used to store the reacted wafers 9;

[0038] The pick-and-place component 3 is used to take out the wafer 9 from the first wafer box 4 and place it in the vacuum chamber 2, and then take out the reacted wafer 9 from the vacuum chamber 2 and place it in the second wafer box 5.

[0039] In other embodiments, the vacuum chamber 2 can also be used as a transition chamber for the transfer of wafer 9 to ensure the cleanliness of the transfer process.

[0040] The wafer transfer device for this epitaxial equipment operates as follows: Valve 21 opens, and the pick-and-place component 3 removes the unreacted wafer 9 from the first wafer cassette 4 and places it in the vacuum chamber 2. After placement, the pick-and-place component 3 extends out of the vacuum chamber 2, valve 21 closes, and a clean environment is created within the vacuum chamber 2 for the reaction. After the reaction, valve 21 reopens, and the pick-and-place component 3 extends into the vacuum chamber 2 to remove the reacted wafer 9 and place it in the second wafer cassette 5. This transfer device ensures that the wafer 9 is transferred within a clean space, avoiding the influence of air disturbances and thus preventing impurity contamination of the wafer surface. This guarantees that the epitaxial layer quality meets standards. The device is simple in structure and easy to operate.

[0041] In this embodiment, both the first cassette 4 and the second cassette 5 are arranged on the cassette support base 6 and located on corresponding two sides of the pick-and-place component 3, and the vacuum chamber 2, the first cassette 4 and the second cassette 5 are arranged in a "product-shaped" layout. The pick-and-place component 3 is located between the first cassette 4 and the second cassette 5. After the pick-and-place component 3 takes out a wafer from the first cassette 4, it can be put into the vacuum chamber 2 after rotating about 90°, and after taking out the wafer from the vacuum chamber 2, it can be put into the second cassette 5 after rotating about 90°. The layout of the first cassette 4, the second cassette 5, the vacuum chamber 2 and the pick-and-place component 3 is relatively reasonable, and the transfer process is simple and convenient.

[0042] In this embodiment, the apparatus body 1 is provided with a door panel 7 for opening or closing the clean space. One side of the door panel 7 is hinged to the apparatus body 1 through a hinge lock 71, and the other side is connected to the apparatus body 1 through an electromagnetic lock 72. The door panel 7 is preferably a glass door panel, and two door panels are provided to facilitate observation of the transfer process in the clean space.

[0043] In this embodiment, the door panel 7 is provided with a limiting piece 73, the limiting piece 73 is provided with a limiting hole 731, and the electromagnetic lock 72 is provided with a locking shaft 723 that can extend into the limiting hole 731. When the door panel 7 is closed, the locking shaft 723 on the electromagnetic lock 72 extends into the limiting hole 731 to realize locking of the door panel 7.

[0044] In this embodiment, the electromagnetic lock 72 comprises an electromagnetic coil 721, a shaft sleeve 722 and a first spring 724. The shaft sleeve 722 is penetrated in the electromagnetic coil 721 and sleeved outside the locking shaft 723, and the first spring 724 is arranged between the shaft sleeve 722 and the locking shaft 723 and used for enabling the locking shaft 723 to extend into the limiting hole 731. When the electromagnetic coil 721 is not powered on, the elastic force of the first spring 724 makes the head of the locking shaft 723 extend out of the shaft sleeve 722, and then extend into the limiting hole 731 to realize locking of the door panel 7. A limit nut 726 is arranged at one end of the locking shaft 723 away from the limiting piece 73. When the locking shaft 723 extends to a certain position, the limit nut 726 abuts against the shaft sleeve 722 to limit the upward movement of the locking shaft 723; when the electromagnetic coil 721 is powered on, the locking shaft 723 is subjected to magnetic force, thereby overcoming the elastic force of the first spring 724 to retract the locking shaft 723, and realizing unlocking of the door panel 7.

[0045] In this embodiment, the end of the locking shaft 723 is provided with a flange portion 725, and the limiting piece 73 is provided with a bending portion 732. Specifically, the diameter of the limiting hole 731 is larger than that of the flange portion 725. When the door panel 7 is being closed, the bending portion 732 abuts against the flange portion 725, and the bending portion 732 exerts a downward force on the flange portion 725, so that the locking shaft 723 overcomes the elastic force and moves downward. When the flange portion 725 moves to the position of the limiting hole 731, the locking shaft 723 extends upward into the limiting hole 731 to realize locking under the action of the elastic force. The up and down directions are as Figure 8 and Figure 9 As shown in the image.

[0046] In this embodiment, the device body 1 is provided with a spring seat 12, and the spring seat 12 is provided with a push block 13 and a second spring 14. The second spring 14 is located between the spring seat 12 and the push block 13 and is used to push the push block 13 out to abut against the closed door panel 7. Figures 6 to 8 As shown, when the door panel 7 is closed to the position where the hinge lock 71 (the hinge lock 71 has a rotating shaft that outputs a signal when it rotates to a designated position; the hinge lock 71 is a commercially available component, and its specific structure will not be described in detail) outputs a signal, the energization of the electromagnetic coil 721 can be delayed for a certain period of time. Due to the delay signal setting, the electromagnetic coil 721 is not energized at this time, the locking shaft 723 is in a high position under the elastic force of the first spring 724, and the push block 13 applies a pushing force to the door panel 7, causing the locking shaft 723 to contact the edge of the limiting hole 731, preventing the door panel 7 from opening. After the delay signal is output, the magnetic force of the electromagnetic coil 721... Used on the locking shaft 723, the flange 725 retracts downward and latches onto the edge of the limiting hole 731, preventing the locking shaft 723 from returning to the low position. When opening the door, it is only necessary to push the door panel 7 to overcome the pushing force of the push block 13, causing a slight displacement, which separates the edge of the limiting hole 731 from the flange 725. Then, the locking shaft 723 retracts to the low position under the influence of magnetic force. At the same time, the pushing force of the push block 13 on the door panel 7 is greater. Since the locking shaft 723 has retracted, the door panel 7 is popped open, completing the door opening action. After the door panel 7 is popped open, the hinge lock 71 has no signal output, the electromagnetic coil 721 is de-energized, and the locking shaft 723 returns to the high position under the action of elasticity. By using a hinge lock 71 with signal output function, the opening and closing status of the door panel 7 can be monitored. When the door panel 7 is open, the hinge lock 71 has no signal output, and components such as the pick-and-place component 3 and the door valve 21 are locked, ensuring the safety of the equipment and the cleanliness of the clean space. When the door panel 7 is closed, the hinge lock 71 outputs the corresponding signal, and the equipment can work normally, ensuring that the components in the clean space are not disturbed by the outside world when they are working.

[0047] In this embodiment, the pick-and-place component 3 includes a robotic arm 31, which is equipped with clean fingers 311. The top surface of the clean fingers 311 is provided with a negative pressure suction port 312. When picking up the wafer, the clean fingers 311 lift the wafer 9 from the bottom surface and use negative pressure to achieve the adsorption requirement without air disturbance.

[0048] In this embodiment, an edge finder 8 for detecting surface defects of the wafer 9 is also provided in the clean space. The edge finder 8 is preferably located below the first wafer cassette 4. After the clean finger 311 retrieves a wafer from the first wafer cassette 4, it is placed on the edge finder 8. The edge finder 8 detects surface defects of the wafer and corrects the wafer retrieval position of the robotic arm 31, thereby significantly improving the repeatability accuracy of the robotic arm 31 in picking up and placing wafers. The clean finger 311 is provided with a first clearance groove 313 for avoiding the edge finder 8, allowing the clean finger 311 to avoid the edge finder 8 when handling the wafer 9, ensuring that the center of the wafer 9 coincides with the center point of the edge finder 8.

[0049] In this embodiment, a tray 22 is provided inside the vacuum chamber 2, and the tray 22 has grooves 221 to reduce the adsorption force between the tray 22 and the wafer 9. To meet cleanliness requirements, the tray 22 is preferably made of quartz material. By setting the grooves 221, the wafer 9 is prevented from making full contact with the surface of the tray 22, reducing the adsorption force. During wafer removal, gas can flow within the grooves 221, reducing the impact of pressure changes in the chamber on the wafer 9 and reducing the fragmentation rate during wafer removal. When transferring large-size wafers, the corresponding grooves 221 can be frosted to further prevent fragmentation caused by increased mirror adsorption force. The tray 22 has a second clearance groove 222 to avoid clean fingers 311 from picking up and placing wafers, facilitating the picking up and placing of wafers by clean fingers 311.

[0050] In this embodiment, to meet cleanliness requirements, the first tablet holder 4 and the second tablet holder 5 are preferably made of high-cleanliness materials such as PP plastic and PC plastic. The tablet holder support 6 is also equipped with multiple tablet holder limiting blocks 62 to limit the tablet holders and prevent displacement when the robotic arm 31 retrieves tablets. The tablet holder support 6 can accommodate tablet holders of different sizes, offering high compatibility (e.g., ...). Figure 2 As shown, for ease of demonstration, the first sheet box 4 and the second sheet box 5 are sheet boxes of different sizes. In actual operation, the first sheet box 4 and the second sheet box 5 are sheet boxes of the same size. At least one photoelectric sensor 61 can be installed on the sheet box support 6 to detect the presence or absence of sheet boxes in real time. In other embodiments, an interlock can be established with the robot arm 31 and the edge finder 8 via a host computer. When the photoelectric sensor 61 has no signal output, the robot arm 31 and the edge finder 8 enter a locked state.

[0051] In this embodiment, the device body 1 is provided with a mounting plate 11, and the cassette support 6 and the pick-and-place component 3 are both provided on the mounting plate 11. The device body 1 is also provided with an EFU air filtration device (Equipment fan filter unit, abbreviated as EFU, which is a commercially available device, and its specific structure will not be described in detail), which is located above the clean space to maintain the air cleanliness in the space.

[0052] While the present invention has been disclosed above with reference to preferred embodiments, it is not intended to limit the invention. Any person skilled in the art can make many possible variations and modifications to the technical solutions of the present invention, or modify them into equivalent embodiments, without departing from the scope of the present invention. Therefore, any simple modifications, equivalent changes, and modifications made to the above embodiments based on the technical essence of the present invention, without departing from the scope of the present invention, should fall within the protection scope of the present invention.

Claims

1. An epitaxial wafer transfer device, comprising a device body (1) and a vacuum cavity (2) disposed on the device body (1), characterized in that: A clean space is provided on the device body (1), and a pick-and-place component (3), a first cassette (4) and a second cassette (5) are arranged in the clean space; The vacuum chamber (2) is configured for epitaxial layer growth and is provided with a gate valve (21), the vacuum chamber (2) is arranged on one side of the clean space, and communication or disconnection between the vacuum chamber and the clean space is achieved through opening and closing of the gate valve (21); The first cassette (4) is configured to store wafers (9) before reaction; the second cassette (5) is configured to store wafers (9) after reaction; the pick-and-place component (3) is configured to take out the wafer (9) from the first cassette (4), place the wafer (9) into the vacuum chamber (2), then take out the reacted wafer (9) from the vacuum chamber (2) and place the reacted wafer (9) into the second cassette (5); the first cassette (4) and the second cassette (5) are both arranged on a cassette support base (6) and located on corresponding two sides of the pick-and-place component (3), and the vacuum chamber (2), the first cassette (4) and the second cassette (5) are arranged in a delta shape; a door panel (7) for opening or closing the clean space is arranged on the device body (1), one side of the door panel (7) is hinged to the device body (1) via a hinge lock (71), and the other side is connected to the device body (1) via an electromagnetic lock (72); the hinge lock (71) has a signal output function; a limiting sheet (73) is arranged on the door panel (7), a limiting hole (731) is formed on the limiting sheet (73), and a locking shaft (723) capable of extending into the limiting hole (731) is arranged on the electromagnetic lock (72); the electromagnetic lock (72) comprises an electromagnetic coil (721), a shaft sleeve (722) and a first spring (724), the shaft sleeve (722) penetrates through the electromagnetic coil (721) and is sleeved outside the locking shaft (723), the first spring (724) is arranged between the shaft sleeve (722) and the locking shaft (723) and is configured to enable the locking shaft (723) to extend into the limiting hole (731); a flange portion (725) is arranged at an end of the locking shaft (723), and a bending portion (732) is arranged on the limiting sheet (73); a spring seat (12) is arranged on the device body (1), a push block (13) and a second spring (14) are arranged on the spring seat (12), the second spring (14) is arranged between the spring seat (12) and the push block (13) and is configured to push out the push block (13) to abut against the closed door panel (7).

2. The epitaxial wafer transfer device according to claim 1, characterized in that: The pick-and-place component (3) comprises a mechanical arm (31), a clean finger (311) is arranged on the mechanical arm (31), and a negative pressure suction port (312) is arranged on the clean finger (311).

3. The epitaxial wafer transfer device according to claim 1, characterized in that: An edge finder (8) for detecting appearance defects of the wafer (9) is further arranged in the clean space.

4. The epitaxial wafer transfer device according to claim 1, characterized in that: A tray (22) is arranged in the vacuum chamber (2), and a groove (221) for reducing adsorption force between the tray (22) and the wafer (9) is arranged on the tray (22).

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