Defect detection device for silicon carbide wafer
By using an electrostatic generator in the silicon carbide wafer defect detection device, the dust on the silicon carbide wafer to be tested is suspended, which solves the problem of dust interference during detection and improves the detection accuracy.
Patent Information
- Application Number
- CN202421307218.7
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2024-06-07
- Publication Date
- 2025-05-13
- Estimated Expiration
- 2034-06-07
AI Technical Summary
The existing silicon carbide wafer defect detection methods are susceptible to interference from particles such as surface dust during detection, resulting in poor accuracy of detection results.
A silicon carbide wafer defect detection device including a first station and an electrostatic generator is designed. The electrostatic generator is located outside the first fixed stage, and can suspend the dust on the silicon carbide wafer to be tested, thereby reducing interference to detection.
The dust is suspended through an electrostatic generator, which reduces the interference of dust on the crystal surface to detection and improves the accuracy of the detection of silicon carbide wafer surface defects by the CCD module.
Smart Images
Figure CN222866569U_ABST
Abstract
Description
Technical Field
[0001] The utility model relates to the technical field of silicon carbide detection equipment, in particular to a defect detection device for a silicon carbide wafer. Background Art
[0002] Silicon carbide (SiC), as an emerging third-generation semiconductor core material, has excellent properties such as wide bandgap, high critical breakdown electric field strength, high electron mobility, good radiation resistance and chemical stability, which makes it an important substrate wafer material with wide applications. It has shown good application prospects in the fields of aviation devices, new energy vehicles, rail transportation and household appliances. Existing silicon carbide wafers generally use CCD modules to perform image recognition on the surface of the wafer to detect defects such as bumps or depressions on the wafer.
[0003] The inventors have found that when some existing CC modules perform image recognition on the surface of a chip, if there is dust or other particles attached to the chip, the images obtained by the CCD are similar, and it is impossible to accurately determine whether it is attached dust or a protrusion on the chip itself, and the detection result has poor accuracy. Utility Model Content
[0004] The utility model aims to provide a defect detection device for a silicon carbide wafer, which can improve the accuracy of detecting surface defects of the silicon carbide wafer.
[0005] The embodiment of the utility model is achieved as follows:
[0006] In a first aspect, the utility model provides a defect detection device for a silicon carbide wafer, comprising:
[0007] A first fixing platform, the first fixing platform is used to place the silicon carbide wafer to be tested;
[0008] The electrostatic generator is located outside the first fixing platform to suspend at least part of the dust on the silicon carbide wafer to be tested placed on the first fixing platform.
[0009] In an optional embodiment, the first fixing platform has a first side and a second side opposite to each other, the first side is used to place the silicon carbide wafer to be tested, and the electrostatic generator is located on the second side or the outer peripheral wall of the first fixing platform.
[0010] In an alternative embodiment, the first side of the first fixing platform is coated with an insulating coating.
[0011] In an optional embodiment, the electrostatic generator includes a discharge structure, a cable and a power supply, both ends of the cable are respectively connected to the discharge structure and the power supply, there are multiple discharge structures and cables, and the multiple discharge structures are spaced apart on the second side of the first fixed platform or the outer peripheral wall of the first fixed platform.
[0012] In an optional embodiment, a second side or an outer peripheral wall of the first fixing platform is provided with a plurality of insulating connectors arranged at intervals, and the insulating connectors are connected to the discharge structure.
[0013] In an optional embodiment, the insulating connector is detachably connected to the discharge structure.
[0014] In an optional embodiment, the discharge structures are arranged at intervals on the second side or the outer peripheral wall of the first fixing platform along the circumferential direction of the first fixing platform.
[0015] In an optional embodiment, the first fixing table is provided with a plurality of vacuum holes arranged at intervals along a preset path, the preset path is circular, and the vacuum holes are used to be connected to a vacuum generator for adsorbing the silicon carbide wafer to be tested.
[0016] In an optional embodiment, the first fixing platform is in a circular ring shape, and the axis of the preset path is coaxial with the first fixing platform.
[0017] In an optional embodiment, the defect detection device also includes a second fixed table and a lifting device, the second fixed table is used to place the silicon carbide wafer to be tested, the first fixed table is provided with a first mounting hole, the second fixed table is located in the first mounting hole and is coaxially arranged with the first fixed table, and the lifting device is connected to the first fixed table and is used to drive the first fixed table to move relative to the second fixed table along its own axis direction.
[0018] The beneficial effect of the embodiment of the utility model is as follows: the defect detection device of a silicon carbide wafer provided by the embodiment of the utility model comprises a first fixed platform and an electrostatic generator. The first fixed platform is used to place the silicon carbide wafer to be tested, and the electrostatic generator is located outside the first fixed platform, so as to suspend at least part of the dust on the silicon carbide wafer to be tested placed on the first fixed platform. Since the electrostatic generator can suspend at least part of the dust on the silicon carbide wafer, when the CCD module detects the surface of the silicon carbide wafer, the interference of the dust on the crystal surface on the detection can be reduced, which can facilitate the CCD module to more accurately detect the defects on the surface of the silicon carbide wafer, thereby improving the accuracy of the detection of surface defects of the silicon carbide wafer. BRIEF DESCRIPTION OF THE DRAWINGS
[0019] In order to more clearly illustrate the technical solutions of the embodiments of the utility model, the drawings required for use in the embodiments will be briefly introduced below. It should be understood that the following drawings only show certain embodiments of the utility model and therefore should not be regarded as limiting the scope. For ordinary technicians in this field, other relevant drawings can be obtained based on these drawings without paying creative work.
[0020] Figure 1 A schematic diagram of the structure of the first fixing platform provided by an embodiment of the utility model at a first viewing angle;
[0021] Figure 2 A schematic structural diagram of a first fixing platform provided in an embodiment of the utility model at a second viewing angle.
[0022] Icons: 100 - first fixing table; 110 - first side; 120 - second side; 130 - vacuum hole; 200 - electrostatic generator; 210 - discharge structure; 220 - cable; 230 - power supply; 300 - insulating connector. DETAILED DESCRIPTION
[0023] In order to make the purpose, technical scheme and advantages of the embodiments of the utility model clearer, the technical scheme in the embodiments of the utility model will be clearly and completely described below in conjunction with the drawings in the embodiments of the utility model. Obviously, the described embodiments are part of the embodiments of the utility model, not all of the embodiments. Generally, the components of the embodiments of the utility model described and shown in the drawings here can be arranged and designed in various different configurations.
[0024] Therefore, the following detailed description of the embodiments of the present invention provided in the accompanying drawings is not intended to limit the scope of the present invention to be protected, but merely represents selected embodiments of the present invention. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.
[0025] It should be noted that similar reference numerals and letters denote similar items in the following drawings, and therefore, once an item is defined in one drawing, further definition and explanation thereof is not required in subsequent drawings.
[0026] In the description of the present utility model, it should be noted that the terms "center", "upper", "lower", "left", "right", "vertical", "horizontal", "inside", "outside", etc. indicate the orientation or position relationship based on the orientation or position relationship shown in the accompanying drawings, or the orientation or position relationship in which the utility model product is usually placed when in use, which is only for the convenience of describing the utility model and simplifying the description, and does not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on the present utility model. In addition, the terms "first", "second", "third", etc. are only used to distinguish the description, and cannot be understood as indicating or implying relative importance.
[0027] In addition, the terms "horizontal", "vertical" and the like do not mean that the components are required to be absolutely horizontal or suspended, but can be slightly tilted. For example, "horizontal" only means that its direction is more horizontal than "vertical", and does not mean that the structure must be completely horizontal, but can be slightly tilted.
[0028] In the description of the present invention, it is also necessary to explain that, unless otherwise clearly specified and limited, the terms "set", "install", "connect", and "connect" should be understood in a broad sense, for example, it can be a fixed 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 it can be indirectly connected through an intermediate medium, or it can be the internal communication 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.
[0029] The specific structure of a defect detection device for a silicon carbide wafer provided by an embodiment of the utility model and the corresponding technical effects it brings are described in detail below in conjunction with the patent drawings.
[0030] Please refer to Figure 1-Figure 2 A defect detection device for a silicon carbide wafer provided by an embodiment of the utility model includes a first fixing table 100 and an electrostatic generator 200 .
[0031] The first fixed table 100 is used to place the silicon carbide wafer to be tested, and the electrostatic generator 200 is located outside the first fixed table 100 to suspend at least part of the dust on the silicon carbide wafer to be tested placed on the first fixed table 100. Since the electrostatic generator 200 can suspend at least part of the dust on the silicon carbide wafer, when the CCD module detects the surface of the silicon carbide wafer, the interference of the dust on the crystal surface on the detection can be reduced, which can facilitate the CCD module to more accurately detect the defects on the surface of the silicon carbide wafer, thereby improving the accuracy of the detection of surface defects of the silicon carbide wafer.
[0032] It is easy to understand that when the electrostatic generator 200 is working, it can generate electric charges, which can make some dust on the silicon carbide crystal placed on the first fixed platform 100 be charged. It is understandable that the electrostatic generator 200 will also generate an electric field around the first fixed platform 100. The electric field strength can make air molecules charge to form positive and negative ions. These ions will then interact with the surrounding dust particles, so that the dust particles are charged. In this process, due to the principle that like charges repel each other, if the electrostatic generator 200 mainly generates ions of the same polarity, then these ions will cause the dust particles to be negatively charged after contacting with the dust particles. These dust particles with the same charge will repel each other, making it difficult to gather. Some will be suspended from the surface of the wafer or the surrounding air due to the action of the electric field force, thereby avoiding interference with dust detection on the surface of the wafer.
[0033] The first fixing platform 100 has a first side 110 and a second side 120 opposite to each other. The first side 110 is used to place the silicon carbide wafer to be tested. The electrostatic generator 200 is located on the second side 120 or the outer peripheral wall of the first fixing platform 100 .
[0034] It can be understood that since the first side 110 is the area where the silicon carbide wafer to be tested is placed, and most of the detection equipment is arranged above the first side 110, and the detection equipment is used to detect surface defects of the silicon carbide wafer to be tested, therefore, the electrostatic generator 200 is arranged on the first side 110 or the outer peripheral wall of the first fixed table 100, which is in the non-detection area, and can reduce electromagnetic interference to precision detection instruments and possible direct electrostatic effects on the wafer.
[0035] Optionally, in some embodiments, the first side 110 of the first fixing platform 100 is coated with an insulating coating. It is understandable that since the first side 110 of the first fixing platform 100 is coated with an insulating coating, it can have a good electrostatic shielding effect and can guide the electrostatic field to avoid damage to the chip.
[0036] In detail, the electrostatic generator 200 includes a power generation structure, a cable 220 and a power supply 230. Both ends of the cable 220 are connected to the discharge structure 210 and the power supply 230 respectively. There are multiple discharge structures 210 and cables 220. The multiple discharge structures 210 are spaced apart on the second side 120 of the first fixed platform 100 or the outer peripheral wall of the first fixed platform 100.
[0037] It can be understood that, since a plurality of discharge structures 210 are provided, the electric field strength at the periphery of the first fixed platform 100 can be enhanced. When the silicon carbide wafer to be tested is placed on the first side 110, more dust on the silicon carbide wafer to be tested can be suspended, thereby better reducing the interference of dust on the crystal surface on the detection, further facilitating the CCD module to more accurately detect defects on the surface of the silicon carbide wafer, thereby improving the accuracy of detecting defects on the surface of the silicon carbide wafer.
[0038] It should be noted that, in order to ensure the discharge structure 210 is insulated from the first fixing platform 100 , a plurality of insulating connectors 300 arranged at intervals are disposed on the second side 120 or the outer peripheral wall of the first fixing platform 100 , and the insulating connectors 300 are connected to the discharge structure 210 .
[0039] It can be understood that the insulating connector 300 can prevent the discharge structure 210 from being electrically connected to the first fixing platform 100 and also ensure the safety of the operators.
[0040] In detail, the insulating connector 300 is detachably connected to the discharge structure 210 , for example, the insulating connector 300 is detachably connected to the discharge structure 210 by plugging or sleeve connection, so that the user can replace the discharge structure 210 in time.
[0041] It should be noted that the above-mentioned discharge structure 210 can be a corona needle or a pointed electrode, which is used to generate corona discharge and release ions. Since the electrostatic generator 200 is a conventional structure, its structure will not be described in detail here.
[0042] The discharge structures 210 are arranged at intervals along the circumference of the first fixing table 100 and the second side 120 or the outer peripheral wall of the first fixing table 100. In some embodiments, the discharge structures 210 are disposed on the lower outer peripheral wall of the first fixing table 100 and relatively close to the first side 110, so that the discharge structures 210 can generate a stronger electric field on the area on the first side 110, so as to suspend more dust on the silicon carbide wafer placed on the first side 110.
[0043] Among them, the first fixed platform 100 is provided with a plurality of vacuum holes 130 arranged at intervals along a preset path, and the preset path is circular. The vacuum holes 130 are used to connect with a vacuum generator for adsorbing the silicon carbide wafer to be tested. It can be understood that since the preset path is circular, the silicon carbide wafer to be tested is generally disc-shaped, thereby more stably adsorbing the silicon carbide wafer.
[0044] In order to more stably adsorb the silicon carbide wafer, the first fixed platform 100 is in a circular shape, and the axis of the preset path is coaxially arranged with the first fixed platform 100. It can be understood that when detecting the silicon carbide wafer, the first fixed platform 100 that generally carries the silicon carbide wafer will also rotate to drive the carried silicon carbide wafer to rotate, and then the surface of the rotating silicon carbide wafer is further inspected. Therefore, since the axis of the preset path is coaxially arranged with the first fixed platform 100, the adsorption force at each position of the silicon carbide wafer can be relatively balanced.
[0045] Optionally, in some embodiments, please refer to Figure 1 The defect detection device also includes a second fixed platform and a lifting device. The second fixed platform is used to place the silicon carbide wafer to be tested. The second fixed platform is located in the first mounting hole and is coaxially arranged with the first fixed platform 100. That is, the radial dimension of the second fixed platform is smaller than the radial dimension of the first fixed platform 100. The lifting device is connected to the first fixed platform 100 and is used to drive the first fixed platform 100 to move relative to the second fixed platform along its own axial direction.
[0046] That is, when testing large-sized silicon carbide wafers, the first fixed platform 100 can be raised by a preset distance, and after a certain height difference is formed with the second fixed platform, the first fixed platform 100 absorbs the large-sized wafer to be tested and drives the large-sized wafer to rotate. When testing small-sized silicon carbide wafers, the first fixed platform 100 can be lowered by a preset distance, and after a certain height difference is formed with the first fixed platform 100, the second fixed platform absorbs the small-sized wafer to be tested and drives the small-sized wafer to rotate, so as to improve the testing efficiency.
[0047] In summary, a defect detection device for a silicon carbide wafer provided by an embodiment of the utility model includes a first fixed platform 100 and an electrostatic generator 200. The first fixed platform 100 is used to place a silicon carbide wafer to be tested, and the electrostatic generator 200 is located outside the first fixed platform 100, so as to suspend at least part of the dust on the silicon carbide wafer to be tested placed on the first fixed platform 100. Since the electrostatic generator 200 can suspend at least part of the dust on the silicon carbide wafer, when the CCD module detects the surface of the silicon carbide wafer, the interference of the dust on the crystal surface on the detection can be reduced, which can facilitate the CCD module to more accurately detect the defects on the surface of the silicon carbide wafer, thereby improving the accuracy of the detection of surface defects of the silicon carbide wafer.
[0048] The above description is only the preferred embodiment of the utility model, and is not intended to limit the utility model. For those skilled in the art, the utility model can have various modifications and changes. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the utility model shall be included in the protection scope of the utility model.
Claims
1. A defect detection device for a silicon carbide wafer, characterized in that: include: A first fixing platform (100), wherein the first fixing platform (100) is used to place a silicon carbide wafer to be tested; An electrostatic generator (200) is located outside the first fixing table (100) so as to suspend at least part of the dust on the silicon carbide wafer to be tested placed on the first fixing table (100).
2. The defect detection device for silicon carbide wafer according to claim 1, characterized in that: The first fixing platform (100) comprises a first side (110) and a second side (120) opposite to each other, the first side (110) being used for placing the silicon carbide wafer to be tested, and the electrostatic generator (200) being located on the second side (120) or the outer peripheral wall of the first fixing platform (100).
3. The defect detection device for silicon carbide wafer according to claim 2, characterized in that: The first side (110) of the first fixing table (100) is coated with an insulating coating.
4. The defect detection device for silicon carbide wafer according to claim 2, characterized in that: The electrostatic generator (200) comprises a discharge structure (210), a cable (220) and a power source (230); two ends of the cable (220) are respectively connected to the discharge structure (210) and the power source (230); there are a plurality of discharge structures (210) and a plurality of cables (220); and the plurality of discharge structures (210) are arranged at intervals on the second side (120) of the first fixing platform (100) or on the outer peripheral wall of the first fixing platform (100).
5. The defect detection device for silicon carbide wafer according to claim 4, characterized in that: A plurality of insulating connectors (300) arranged at intervals are provided on the second side (120) or the outer peripheral wall of the first fixing platform (100), and the insulating connectors (300) are connected to the discharge structure (210).
6. The defect detection device for silicon carbide wafer according to claim 5, characterized in that: The insulating connector (300) is detachably connected to the discharge structure (210).
7. The defect detection device for silicon carbide wafer according to claim 4, characterized in that: The discharge structures (210) are arranged at intervals along the circumferential direction of the first fixing platform (100) on the second side (120) or the outer peripheral wall of the first fixing platform (100).
8. The defect detection device for silicon carbide wafer according to claim 1, characterized in that: The first fixing platform (100) is provided with a plurality of vacuum holes (130) arranged at intervals along a preset path, the preset path is circular, and the vacuum holes (130) are used to be connected to a vacuum generator for adsorbing the silicon carbide wafer to be tested.
9. The defect detection device for silicon carbide wafer according to claim 8, characterized in that: The first fixing platform (100) is in the shape of a circular ring, and the axis of the preset path is coaxial with the first fixing platform (100).
10. The defect detection device for silicon carbide wafer according to claim 9, characterized in that: The defect detection device further comprises a second fixed platform and a lifting device, wherein the second fixed platform is used to place the silicon carbide wafer to be tested, the first fixed platform (100) is provided with a first mounting hole, the second fixed platform is located in the first mounting hole and is coaxially arranged with the first fixed platform (100), and the lifting device is connected to the first fixed platform (100) and is used to drive the first fixed platform (100) to move relative to the second fixed platform along its own axis direction.