Automatic feeding and discharging system of SiC epitaxial equipment

Abstract

The utility model provides an automatic loading and unloading system of SiC epitaxial equipment, which comprises a transfer disc and a wafer transfer mechanical arm which are used for transferring graphite discs, coating rings and wafers; the graphite disc cleaning and positioning device is used for blowing, cleaning and positioning the graphite disc; the coating ring and wafer separating and positioning device is used for separating and positioning the coating ring and the wafer; the wafer feeding device is used for storing wafers of which the process is not completed; the wafer discharging device is used for storing the wafers subjected to the process; the graphite disc cleaning and positioning device, the wafer feeding device, the wafer discharging device and the wafer separating and positioning device are all arranged on the outer sides of the disc conveying and the wafer conveying mechanical arm; the graphite disc cleaning and positioning device and the coating ring and wafer separation and positioning device are respectively provided with a positioner for identifying the direction of the graphite disc and calibrating the positioning edges of the coating ring and the wafer; the graphite disc cleaning and positioning device comprises an air blowing device and an air extracting device, the air blowing device blows the disc face of the graphite disc, and the air extracting device extracts blown particles.

Description

Technical Field

[0001] The utility model relates to silicon carbide epitaxial equipment, in particular to an automatic loading and unloading system for SiC epitaxial equipment. Background Art

[0002] Silicon carbide semiconductors have excellent properties such as a wide bandgap, excellent stability, high thermal conductivity, high critical breakdown field strength, and high saturated electron drift velocity. They are ideal semiconductor materials for manufacturing high-temperature, high-frequency, high-power, and high-radiation power electronic devices. The silicon carbide material used to make silicon carbide devices is typically silicon carbide epitaxial wafers grown on silicon carbide substrates.

[0003] Silicon carbide epitaxial growth has been commercialized, typically using CVD (chemical vapor deposition) to grow silicon carbide epitaxial wafers. Currently, the majority of commercial epitaxial furnaces are horizontal reactor-type epitaxial furnaces. Currently, most horizontal reactor-type epitaxial furnaces (LPE) are semi-automatic, requiring a large number of personnel to manually load and unload wafers and clean graphite plates. This results in low efficiency and is prone to human error and incomplete graphite plate cleaning during loading and unloading operations, resulting in wafer damage and contamination, which reduces yield. The commercialization of silicon carbide epitaxial growth requires consideration of how to improve automation to enhance epitaxial wafer production capacity and quality. Utility Model Content

[0004] Aiming to solve the problem of manual operation in existing silicon carbide epitaxial equipment, the utility model provides an automatic loading and unloading system for SiC epitaxial equipment, which can automatically separate and clean the graphite disk, independently position the graphite disk, coating ring and wafer, realize automatic wafer transfer, have high efficiency and minimize human interference factors.

[0005] In order to solve the above technical problems, the utility model provides an automatic loading and unloading system for SiC epitaxial equipment, comprising:

[0006] The disc and wafer transfer robot arm is composed of a disc transfer robot arm and a wafer transfer robot arm. The disc transfer robot arm is used to transfer graphite discs, coating rings, and wafers, and the wafer transfer robot arm is used to load, unload and transfer wafers.

[0007] Graphite disk cleaning and positioning device, for blowing, cleaning and positioning the graphite disk;

[0008] The coating ring and wafer separation and positioning device separates and positions the coating ring and wafer;

[0009] Wafer loading device, used to store wafers that have not completed the process;

[0010] Wafer unloading device, used to store wafers that have completed the process;

[0011] The graphite disk cleaning and positioning device, wafer loading device, wafer unloading device and wafer separation and positioning device are all arranged on the outside of the disk transfer and wafer transfer robot arm;

[0012] The graphite disk cleaning and positioning device and the coating ring and wafer separation and positioning device are both provided with positioners for identifying the direction of the graphite disk and calibrating the coating ring and wafer positioning edges;

[0013] The graphite disk cleaning and positioning device includes a cleaning device, which includes a blowing device and an exhaust device. The blowing device is used to blow the disk surface of the graphite disk, and the exhaust device is used to extract the blown particles.

[0014] In a preferred embodiment, the disc transfer and film transfer robot arm also includes a linear drive module, which includes a first lateral moving guide rail and a second lateral moving guide rail, and a movable platform is installed on the second lateral moving guide rail, and the disc transfer robot arm and film transfer robot arm are arranged up and down on the movable platform.

[0015] In a preferred embodiment, the movable platform is provided with a lifting device and a first telescopic device and a second telescopic device, and the lifting device allows the disc transfer robot arm and the film transfer robot arm to move up and down;

[0016] The first telescopic device allows the disk transfer robot arm to extend or retract horizontally; the second telescopic device allows the film transfer robot arm to extend or retract horizontally.

[0017] In a preferred embodiment, the movable platform is rotatably mounted on the second transverse movable guide rail, and the movable platform is connected to a rotary motor.

[0018] In a preferred embodiment, the wafer loading device and the wafer unloading device each include a placement cavity, wherein guide transverse grooves are arranged in the placement cavity at intervals, and the guide transverse grooves are symmetrically arranged on both sides of the placement cavity;

[0019] The two symmetrical groups of guide transverse grooves are used to cooperate in placing a wafer, and the gap is used for the grasping member of the wafer transfer robot arm to extend in and out.

[0020] In a preferred embodiment, a positioning frame is provided on one side of the graphite disk cleaning positioning device and the coating ring and wafer separation positioning device, the positioner is fixed on the positioning frame, and the positioner is provided above the graphite disk cleaning positioning device or the coating ring and wafer separation positioning device.

[0021] In a preferred embodiment, the locator is a camera.

[0022] In a preferred embodiment, a rotating downward pressure cylinder is provided on the side of the graphite disk cleaning and positioning device for driving the cleaning device to clean the graphite disk.

[0023] In a preferred embodiment, the cleaning device includes a cleaning cover, and the cleaning cover is used to cover the graphite disk;

[0024] An air inlet and an air extraction port are provided in the cleaning cover. The air inlet is connected to the air blowing device, and the air extraction port is connected to the air extraction device.

[0025] In a preferred embodiment, argon gas is introduced into the blowing device.

[0026] Compared with the existing technology, the technical solution of the utility model has the following beneficial effects:

[0027] 1. By installing a plate transfer and wafer transfer robot arm, a graphite plate cleaning and positioning device, a coating ring and wafer separation and positioning device, a wafer loading device, and a wafer unloading device, the wafer loading and unloading process is automated, solving the problem of human operational errors in the growth process, thereby improving the production capacity of the LPE epitaxial furnace and the surface yield of the epitaxial wafers.

[0028] 2. By setting up an air blowing device and an air extraction device on the graphite disk cleaning and positioning device, the graphite disk can be automatically cleaned, avoiding the damage to the epitaxial wafer / reduction in yield caused by substandard operation when manually cleaning the graphite disk with an air gun. BRIEF DESCRIPTION OF THE DRAWINGS

[0029] Figure 1 This is an overall diagram of the automatic loading and unloading system in the preferred embodiment of the utility model;

[0030] Figure 2 This is a structural diagram of a wafer loading device and a wafer unloading device in a preferred embodiment of the present invention;

[0031] Figure 3 This is a structural diagram of the disk transfer and film transfer robotic arms in a preferred embodiment of the present invention;

[0032] Figure 4 This is a structural diagram of a graphite disk cleaning and positioning device in a preferred embodiment of the present utility model;

[0033] Figure 5 This is a structural diagram of the cleaning device in a preferred embodiment of the present utility model.

[0034] Explanation of the accompanying reference numerals: 1. Disc and wafer transfer robot arm; 11. Disc transfer robot arm; 12. Wafer transfer robot arm; 13. First lateral moving guide rail; 14. Second lateral moving guide rail; 15. Moving platform; 16. Lifting device; 17. First telescopic device; 18. Second telescopic device; 2. Graphite disc cleaning and positioning device; 21. Cleaning device; 22. Rotary downward pressure cylinder; 23. Cleaning cover; 3. Coating ring and wafer separation and positioning device; 4. Wafer loading device; 41. Placement cavity; 42. Guide transverse groove; 43. Wafer; 5. Wafer unloading device; 6. Positioning frame; 61. Camera. DETAILED DESCRIPTION

[0035] The technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention; it is obvious that the described embodiments are only part of the embodiments of the present invention, rather than all the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative work are within the scope of protection of the present invention.

[0036] In the description of this utility model, it should be noted that the terms "upper," "lower," "inner," "outer," "top / bottom," and the like, indicating orientations or positional relationships, are based on the orientations or positional relationships shown in the accompanying drawings and are intended solely to facilitate the description of this utility model and simplify the description. They are not intended to indicate or imply that the devices or components referred to must have a specific orientation, be constructed, or operate in a specific orientation. Therefore, they should not be construed as limitations on this utility model. Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance.

[0037] In the description of the present invention, it should be noted that, unless otherwise clearly specified and limited, the terms "installed", "provided with", "set / connected", "connected", etc. should be understood in a broad sense. For example, "connection" can be a wall-mounted connection, a detachable connection, or an integral connection. It can be a mechanical connection or an electrical connection. It can be a direct connection or an indirect connection through an intermediate medium. It can be the internal connection of two components. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0038] Currently, in the process of growing silicon carbide epitaxially using an LPE horizontal epitaxial furnace, when feeding wafers, manual work is required to use jigs to retrieve, position, and place the wafers; when unloading wafers, manual work is still required to use jigs to retrieve the wafers and to clean the graphite disks with an air gun. During this operation, if the personnel operate improperly or the cleaning of the jigs / graphite disks does not meet the standards, the epitaxial wafers may be damaged or the yield may be reduced. To address this problem of defective rates, the present embodiment provides an automatic loading and unloading system for silicon carbide epitaxial equipment that can automatically separate and clean the graphite disks, individually position the graphite disks, coating rings, and wafers, and achieve automatic wafer transfer. This system is highly efficient and has minimal human interference factors. This system can automate the loading and unloading processes of the LPE horizontal epitaxial furnace, thereby improving the production capacity of the LPE epitaxial furnace and the quality of the epitaxial wafers.

[0039] refer to Figure 1-Figure 5 , the automatic loading and unloading system of SiC epitaxial equipment includes:

[0040] The plate transfer and wafer transfer robot 1 is composed of a plate transfer robot 11 and a wafer transfer robot 12. The plate transfer robot 11 can be used to transfer graphite plates, coating rings, and wafers 43, and the wafer transfer robot 12 can be used to load, unload, and transfer wafers 43;

[0041] Graphite disk cleaning and positioning device 2, capable of blowing, cleaning and positioning the graphite disk;

[0042] The coating ring and wafer separation and positioning device 3 is capable of separating and positioning the coating ring and wafer 43;

[0043] Wafer loading device 4, used to store unfinished wafers 43;

[0044] The wafer unloading device 5 is used to store the wafers 43 that have completed the process.

[0045] Among them, the wafer loading device 4 and the wafer unloading device 5 are mainly used for protecting and placing the wafer 43. The graphite disk cleaning and positioning device 2, the wafer loading device 4, the wafer unloading device 5, and the wafer 43 separation and positioning device are all located outside the disk transfer and wafer transfer robot arm 1. The graphite disk cleaning and positioning device 2 and the coating ring and wafer separation and positioning device 3 are all equipped with positioners for identifying the direction of the graphite disk and calibrating the positioning edge of the coating ring and the wafer 43. The graphite disk cleaning and positioning device 2 includes a cleaning device 21, which includes an air blowing device and an air extraction device. The air blowing device is used to purge the disk surface of the graphite disk, and the air extraction device is used to extract the purged particles. Through this automatic loading and unloading system for SiC epitaxial growth equipment, the loading and unloading process can be automated, solving the problem of human operational errors in the growth process, thereby improving the production capacity of the LPE epitaxial furnace and the surface yield of the epitaxial wafers.

[0046] The plate transfer and wafer transfer robot 1 also includes a linear drive module, which serves as the primary driver for transporting the graphite plate, coating ring, and wafer 43. The linear drive module includes a first lateral guide rail 13 and a second lateral guide rail 14, with a movable platform 15 mounted on the second lateral guide rail 14. The plate transfer robot 11 and wafer transfer robot 12 are positioned one above the other on the movable platform 15.

[0047] The movable platform 15 is rotatably mounted on the second transverse guide rail 14. A rotary motor is connected to the bottom of the movable platform. The rotary motor provides rotation of the movable platform 15 relative to the second transverse guide rail 14, facilitating the wafer transfer robot 11 and the wafer transfer robot 12 to turn and transfer the wafer 43. A lifting device 16, a first telescopic device 17, and a second telescopic device 18 are mounted on the movable platform 15. The lifting device 16 allows the wafer transfer robot and the wafer transfer robot to move up and down, the first telescopic device 17 allows the wafer transfer robot to extend or retract horizontally, and the second telescopic device 18 allows the wafer transfer robot to extend or retract horizontally, facilitating the wafer transfer robot 11 and the wafer transfer robot 12 to load and unload the wafer 43.

[0048] The wafer loading device 4 and the wafer unloading device 5 each include a placement chamber 41, within which are disposed transverse guide grooves 42 spaced apart vertically. The transverse guide grooves 42 are symmetrically disposed on either side of the placement chamber 41. The two symmetrical sets of transverse guide grooves 42 are used to accommodate a wafer 43. The spacing allows for the gripper of the wafer transfer robot 12 to extend and enter, facilitating the acquisition and placement of the wafer 43.

[0049] The graphite cleaning and positioning device is a device used to clean and position graphite disks. Graphite disks, also known as SiC-coated graphite susceptors or suceptors, are key components used to support and heat single crystal substrates in metal-organic chemical vapor deposition (MOCVD) equipment. Their thermal stability and uniformity are crucial to the quality of epitaxial material growth. Corrosive gases and residual metal organic matter can cause the graphite disk to corrode and shed, which not only shortens its lifespan but can also contaminate the chip. Therefore, the graphite disks must be regularly cleaned to remove surface contaminants. The graphite cleaning and positioning device is designed to perform this cleaning task. It uses automation to improve cleaning efficiency and ensures that the graphite disk is accurately positioned after cleaning for reuse.

[0050] The graphite disk cleaning and positioning device 2 is used to separate the graphite disk from the coating ring and wafer 43, clean the graphite disk, and calibrate the disk's positioning edge. It consists of a disk and wafer transfer robot 1, a linear drive module, a cleaning device 21, and a positioning and alignment mechanism. The positioning and alignment mechanism includes a positioner and an alignment mechanism. The alignment mechanism utilizes existing graphite alignment mechanisms, with the positioner being a camera 61. By taking a picture, the graphite disk's orientation can be identified, and the alignment mechanism rotates and adjusts the disk accordingly.

[0051] The cleaning device 21 includes a cleaning hood 23, a blowing device, and an exhaust device. The cleaning hood 23 is used to cover the graphite disk and is provided with an air inlet and an exhaust port. The air inlet is connected to the blowing device, and the exhaust port is connected to the exhaust device. The cleaning hood operates by covering the graphite disk and introducing argon gas to purge the disk surface. After the purge is completed, the hood begins to exhaust the gas to remove the purged particles.

[0052] The driving of the cleaning cover 23 is that a rotating downward pressure cylinder 22 is provided on the side of the graphite disk cleaning and positioning device, which is used to drive the cleaning device 21 to rotate and press downward to clean the graphite disk.

[0053] The coating ring and wafer separation and positioning device 3 is a device used to precisely place and position the wafer 43. It can be used to separate the coating ring from the wafer 43 and calibrate the alignment edges of the coating ring and wafer 43. A locator, a camera 61, is located above the coating ring and wafer separation and positioning device 3. This locator, which is a camera 61, takes photos and identifies the alignment edges of the coating ring and wafer 43 for calibration, ensuring the correct position of the wafer 43 within the coating ring. The separation of the coating ring and wafer 43 and the calibration equipment used with the locator can utilize existing separation and calibration equipment.

[0054] The positioner is installed as follows: a positioning frame 6 is provided on one side of the graphite disk cleaning positioning device and the coating ring and chip separation positioning device 3, and the camera 61 is fixed on the positioning frame 6, and the camera 61 is provided above the graphite disk cleaning positioning device or the coating ring and chip separation positioning device 3.

[0055] This embodiment provides an automatic loading and unloading system for SiC epitaxial equipment. The system realizes the functions of automatically separating graphite disks, coating rings, and wafers, automatically cleaning graphite disks, automatically calibrating positioning edges, and automatically conveying. It solves the problem of wafer defects / damage caused by human factors during the manual loading and unloading process, thereby improving the production capacity of the epitaxial furnace and the yield of epitaxial wafers.

[0056] The above is only a preferred specific implementation method of the present invention, but the design concept of the present invention is not limited to this. Any technician familiar with the technical field who uses this concept to make non-substantial changes to the present invention within the technical scope disclosed by the present invention shall be deemed to infringe the protection scope of the present invention.

Claims

1. An automatic loading and unloading system for SiC epitaxial equipment, characterized by: include; The disc and wafer transfer robot arm is composed of a disc transfer robot arm and a wafer transfer robot arm. The disc transfer robot arm is used to transfer graphite discs, coating rings, and wafers, and the wafer transfer robot arm is used to load, unload and transfer wafers. Graphite disk cleaning and positioning device, for blowing, cleaning and positioning the graphite disk; The coating ring and wafer separation and positioning device separates and positions the coating ring and wafer; Wafer loading device, used to store wafers that have not completed the process; Wafer unloading device, used to store wafers that have completed the process; The graphite disk cleaning and positioning device, the wafer loading device, the wafer unloading device and the wafer separation and positioning device are all arranged on the outside of the wafer transfer and wafer transfer robot arm; The graphite disk cleaning and positioning device and the coating ring and wafer separation and positioning device are both provided with positioners for identifying the direction of the graphite disk and calibrating the coating ring and wafer positioning edges; The graphite disk cleaning and positioning device includes a cleaning device, which includes a blowing device and an exhaust device. The blowing device is used to blow the disk surface of the graphite disk, and the exhaust device is used to extract the blown particles.

2. The automatic loading and unloading system for SiC epitaxial equipment according to claim 1, characterized in that: The disc transfer and film transfer robot arm also includes a linear drive module, which includes a first lateral moving guide rail and a second lateral moving guide rail, and a movable platform is installed on the second lateral moving guide rail. The disc transfer robot arm and the film transfer robot arm are arranged up and down on the movable platform.

3. The automatic loading and unloading system for SiC epitaxial equipment according to claim 2, characterized in that: The movable platform is provided with a lifting device and a first telescopic device and a second telescopic device, and the lifting device allows the disc transfer robot arm and the film transfer robot arm to move up and down; The first telescopic device allows the disk transfer robot arm to extend or retract horizontally; the second telescopic device allows the film transfer robot arm to extend or retract horizontally.

4. The automatic loading and unloading system for SiC epitaxial equipment according to claim 3, characterized in that: The moving platform is rotatably mounted on the second transverse moving guide rail, and the moving platform is connected to a rotating motor.

5. The automatic loading and unloading system for SiC epitaxial equipment according to claim 4, characterized in that: The wafer loading device and the wafer unloading device each include a placement cavity, wherein guide transverse grooves are arranged in an upper and lower interval in the placement cavity, and the guide transverse grooves are symmetrically arranged on both sides of the placement cavity; The two symmetrical groups of guide transverse grooves are used to cooperate in placing a wafer, and the gap is used for the grasping member of the wafer transfer robot arm to extend in and out.

6. The automatic loading and unloading system for SiC epitaxial equipment according to claim 5, characterized in that: A positioning frame is provided on one side of the graphite disk cleaning positioning device and the coating ring and wafer separation positioning device. The positioner is fixed on the positioning frame and is provided above the graphite disk cleaning positioning device or the coating ring and wafer separation positioning device.

7. The automatic loading and unloading system for SiC epitaxial equipment according to claim 6, characterized in that: The locator is a camera.

8. The automatic loading and unloading system for SIC epitaxial equipment according to claim 1, characterized in that: A rotating downward-pressing cylinder is provided on the side of the graphite disk cleaning and positioning device, which is used to drive the cleaning device to clean the graphite disk.

9. The automatic loading and unloading system for SiC epitaxial equipment according to claim 1, characterized in that: The cleaning device includes a cleaning cover, and the cleaning cover is used to cover the graphite disk; An air inlet and an air extraction port are provided in the cleaning cover. The air inlet is connected to the air blowing device, and the air extraction port is connected to the air extraction device.

10. The automatic loading and unloading system for SiC epitaxial equipment according to claim 9, characterized in that: Argon gas is introduced into the blowing device.

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