Low deformation high parallelism fusion bonding clamp
Patent Information
- Application Number
- CN202522244964.7
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2025-10-23
- Publication Date
- 2026-09-15
- Estimated Expiration
- 2035-10-23
AI Technical Summary
[0019]1. This fixture uses pressure plate limiting plates to limit the pressure plate of the bonding fixture, so as to control the concentricity of the bonding between the epitaxial wafer body and the AVG glass body, and at the same time control the parallelism of the entire fixture to prevent excessive parallelism of the product; at the same time, all parts of this fixture are made of graphite as thermally conductive material, so as to achieve effective heat conduction during the molten bonding process.
Smart Images
Figure CN224751122U_ABST
Abstract
Description
Technical Field
[0001] This utility model belongs to the field of fusion bonding fixture technology, and specifically relates to a fusion bonding fixture with low deformation and high parallelism. Background Technology
[0002] Low-light image intensifiers transform objects that are difficult for the human eye to observe under dim nighttime lighting into visible optical images through photoelectric-optical image conversion, enhancement, and display. They are widely used in military, public security, and astronomical fields. The third generation of low-light image intensifiers, developed in the 1980s, uses GaAs material with negative electron affinity as the photocathode. It offers advantages such as higher sensitivity and resolution, and a wide spectral response. It mainly consists of four parts: an optical imaging system, a GaAs photocathode, a microchannel plate, and a fluorescent screen. The GaAs photocathode's role is to convert the weak optical image into an electronic image; it is the core component of the low-light image intensifier, and its quality determines the intensifier's performance.
[0003] The fabrication process of GaAs negative electron affinity photocathodes includes GaAs substrate preparation, GaAs epitaxial layer growth, silicon nitride film deposition, bonding of the window material (AVG glass) to the GaAs epitaxial wafer, selective chemical etching, and electrode evaporation. There are various bonding methods for AVG glass and GaAs epitaxial wafers, with fusion bonding being the most common. Fusion bonding involves holding the AVG glass and GaAs epitaxial wafer at high temperature in a high vacuum, molten the AVG glass, and then applying external force to bond them together. Large-area photocathode components produced by this bonding exhibit strong adhesion, no bubbles, and good uniformity, meeting the requirements for third-generation photocathode development.
[0004] During the fusion bonding process, pressure is applied to the bonding surface, requiring the fixture components to have good parallelism and low deformation to ensure consistency in bonding results from different bonding instruments and prevent inconsistencies in image tube performance caused by subsequent processes. Therefore, designing a fusion bonding fixture with low deformation and high parallelism for high vacuum is crucial for the quality and yield of GaAs electron affinity photocathodes. Utility Model Content
[0005] The purpose of this invention is to address the shortcomings of existing technologies by proposing a low-deformation, high-parallelism melt-bonding fixture.
[0006] To achieve the above objectives, the present invention adopts the following technical solution: a low deformation and high parallelism fusion bonding fixture, comprising: a bonding fixture pressure plate, a pressure plate limiting plate, an AVG tray, an epitaxial wafer limiting plate, and a bonding fixture base;
[0007] One side of the bonding fixture pressure plate is integrally formed with a mounting boss, and a steel ball is snapped into the inner side of the mounting boss, and the steel ball has the weight to press down on the bonding fixture pressure plate.
[0008] The pressure plate limiting piece is located on the side of the bonding fixture pressure plate away from the steel ball, and the pressure plate limiting piece is used to achieve coaxial positioning.
[0009] The AVG tray is located on the side of the pressure plate limiting piece away from the bonding fixture pressure plate, and the side of the AVG tray close to the pressure plate limiting piece has a concave surface, while the side away from the pressure plate limiting piece has a convex surface.
[0010] The epitaxial wafer limiting plate is located on the convex side of the AVG tray, and the bonding fixture base is sleeved on the outside of the bonding fixture pressure plate, the pressure plate limiting plate, the AVG tray, and the epitaxial wafer limiting plate.
[0011] Preferably, the AVG glass body is placed in the concave surface on one side of the AVG tray, while the convex surface on the other side of the AVG tray serves to ensure parallelism.
[0012] Preferably, the inner wall of the bonding fixture base is provided with bonding fixture positioning posts that are snap-fitted together at equal intervals, and the number of bonding fixture positioning posts is three.
[0013] Preferably, one end of the bonding fixture positioning post passes through the epitaxial wafer limiting plate, the AVG tray, and the pressure plate limiting plate in sequence.
[0014] Preferably, the inner side of the epitaxial wafer limiting disk is provided with positioning holes located outside the boss and distributed circumferentially, and the positioning holes are used for insertion and positioning with the positioning post of the bonding fixture.
[0015] Preferably, the pressure plate limiting piece and the AVG tray have circumferentially shaped positioning holes inside, and the positioning holes are used for insertion and positioning with the positioning post of the bonding fixture.
[0016] Preferably, a spring is sleeved on the surface of the bonding fixture positioning post, one end of the spring is engaged with the bonding fixture positioning post, and the other end passes through the epitaxial wafer limiting plate to the side of the AVG tray away from the pressure plate limiting plate.
[0017] Preferably, the epitaxial wafer limiting disk has a boss on the side near the AVG tray, and the boss has a recess for limiting and engaging the epitaxial wafer body.
[0018] In summary, this utility model has the following beneficial effects:
[0019] 1. This fixture uses pressure plate limiting plates to limit the pressure plate of the bonding fixture, so as to control the concentricity of the bonding between the epitaxial wafer body and the AVG glass body, and at the same time control the parallelism of the entire fixture to prevent excessive parallelism of the product; at the same time, all parts of this fixture are made of graphite as thermally conductive material, so as to achieve effective heat conduction during the molten bonding process.
[0020] 2. This fixture adopts a stacked component structure. Coaxial constraint on the entire fixture is achieved through the bonding fixture positioning posts and the positioning holes and insertion holes between the components. The perfect fit between the components ensures bonding parallelism. Furthermore, the height limiting effect of the AVG tray and the small parallelism difference effectively guarantee the consistency of bonding height deformation. Finally, compared with traditional bonding fixtures, this bonding fixture, combined with the high-temperature fusion bonding process, effectively controls product consistency and significantly improves bonding success rate.
[0021] 3. During the fusion bonding process, this fixture applies pressure to the bonding surface, requiring all components of the fixture to have good parallelism and low deformation to ensure consistency in bonding results from different bonding instruments and to avoid inconsistencies in image tube performance caused by subsequent processes. Therefore, designing a fusion bonding fixture with low deformation and high parallelism for high vacuum is crucial to the quality and yield of the epitaxial wafer bulk negative electron affinity photocathode. Attached Figure Description
[0022] Figure 1 This is a three-dimensional structural diagram of the present invention;
[0023] Figure 2 This is an exploded view of the present invention;
[0024] Figure 3 This is an enlarged cross-sectional view of the present invention.
[0025] Figure label:
[0026] 1. Steel balls;
[0027] 2. Bonding fixture pressure plate; 201. Mounting boss;
[0028] 3. Pressure plate limit plate;
[0029] 4. AVG tray; 401. Positioning socket;
[0030] 5. Epitaxial wafer limiting plate; 501. Positioning hole;
[0031] 6. Bonding fixture base;
[0032] 7. Spring;
[0033] 8. Bonding fixture positioning post;
[0034] 9. Epitaxial wafer body;
[0035] 10. AVG glass body. Detailed Implementation
[0036] To make the technical means, creative features, and achieved objectives and effects of this utility model easier to understand, the present utility model is further described below with reference to specific embodiments and accompanying drawings. However, the following embodiments are merely preferred embodiments of this utility model and not all of them. Other embodiments obtained by those skilled in the art based on the embodiments described in the implementation plan without creative effort are all within the protection scope of this utility model.
[0037] The specific embodiments of this utility model are described below with reference to the accompanying drawings: Example
[0038] refer to Figures 1-3 A low-deformation, high-parallelism melt bonding fixture includes: a bonding fixture pressure plate 2, a pressure plate limiting plate 3, an AVG tray 4, an epitaxial wafer limiting plate 5, and a bonding fixture base 6.
[0039] One side of the bonding fixture pressure plate 2 is integrally formed with a mounting boss 201. A steel ball 1 is snapped into the inner side of the mounting boss 201, and the steel ball 1 has the weight to press down on the bonding fixture pressure plate 2.
[0040] The pressure plate limiting piece 3 is located on the side of the bonding fixture pressure plate 2 away from the steel ball 1, and the pressure plate limiting piece 3 is used to achieve coaxial positioning.
[0041] The AVG tray 4 is located on the side of the pressure plate limiting piece 3 away from the bonding fixture pressure plate 2, and the side of the AVG tray 4 close to the pressure plate limiting piece 3 has a concave surface, while the side away from the pressure plate limiting piece 3 has a convex surface.
[0042] The epitaxial wafer limiting plate 5 is located on the convex side of the AVG tray 4, and the bonding fixture base 6 is sleeved on the outside of the bonding fixture pressure plate 2, the pressure plate limiting plate 3, the AVG tray 4 and the epitaxial wafer limiting plate 5.
[0043] Specifically, this fixture adopts a stacked component structure. Coaxial constraint on the entire fixture is achieved through the bonding fixture positioning posts 8 and the positioning holes 501 and positioning insertion holes 401 between the components. The perfect fit between the components ensures bonding parallelism. Furthermore, the height limiting effect of the AVG tray 4 and the small parallelism difference effectively guarantee the consistency of bonding height deformation. Finally, compared to traditional bonding fixtures, this bonding fixture, combined with the high-temperature fusion bonding process, effectively controls product consistency and significantly improves bonding success rate.
[0044] An AVG glass body 10 is placed in the concave surface on one side of the AVG tray 4, while the convex surface on the other side of the AVG tray 4 serves to ensure parallelism.
[0045] Specifically, the AVG tray 4 has a flat disc-shaped structure. The side near the pressure plate limiting piece 3 has a concave design, while the side away from the pressure plate limiting piece 3 has a convex design. The concave surface can limit the AVG glass body, while the convex surface can ensure parallelism by controlling the deformation of the photocathode boss after bonding.
[0046] The inner wall of the bonding fixture base 6 is provided with three bonding fixture positioning posts 8 that are snap-fitted together. One end of each bonding fixture positioning post 8 passes through the epitaxial wafer limiting plate 5, the AVG tray 4, and the pressure plate limiting plate 3 in sequence. The inner side of the epitaxial wafer limiting plate 5 is provided with positioning holes 501 located outside the boss and distributed circumferentially. The positioning holes 501 are used for insertion and positioning with the bonding fixture positioning posts 8. The pressure plate limiting plate 3 and the AVG tray 4 are provided with positioning insertion holes 401 circumferentially inside. The positioning insertion holes 401 are used for insertion and positioning with the bonding fixture positioning posts 8. A spring 7 is sleeved on the surface of the bonding fixture positioning post 8. One end of the spring 7 is snap-fitted to the bonding fixture positioning post 8, and the other end passes through the epitaxial wafer limiting plate 5 to the side of the AVG tray 4 away from the pressure plate limiting plate 3.
[0047] Specifically, the bonding fixture positioning post 8 has a cylindrical structure, consisting of a cylinder with a height of 5mm and a diameter of 6mm and a cylinder with a diameter of 3mm and a height of 25mm. When it is inserted into the positioning hole 501 and the positioning insertion hole 401, the positioning post can achieve coaxial positioning of the epitaxial wafer limiting plate 5, the AVG tray and the pressure plate limiting plate 3 respectively.
[0048] The epitaxial wafer limiting disk 5 has a boss on the side near the AVG tray 4, and the boss has a recess for limiting and engaging the epitaxial wafer body 9.
[0049] Specifically, the protrusion and its internal pit formed on one side of the epitaxial wafer limiting disk 5 can limit the epitaxial wafer body 9 and control the bonding parallelism, which is crucial for obtaining low bonding deformation.
[0050] The working principle of this utility model is as follows: In use, the fixture is assembled sequentially. The epitaxial wafer limiting plate 5 is taken and fitted onto the bonding fixture positioning post 8 through the positioning hole 501. The protrusion and internal recess formed on one side of the epitaxial wafer limiting plate 5 then limit the position of the epitaxial wafer body 9. Next, the AVG tray 4 is taken and fitted onto the bonding fixture positioning post 8 through the positioning insertion hole 401. The AVG tray 4 has a flat disc-shaped structure, with a concave design on the side near the pressure plate limiting piece 3 and a convex design on the side away from the pressure plate limiting piece 3. The concave surface limits the AVG glass body, thus initially completing the positioning of the AVG glass body 10 and the epitaxial wafer body 9.
[0051] Next, the above operation is repeated to continue using the positioning socket 401 to assemble and position the pressure plate limiting piece 3. Then, the bonding fixture pressure plate 2 is assembled and placed inside the pressure plate limiting piece 3. The pressure plate limiting piece 3 limits the bonding fixture pressure plate 2 to control the concentricity of the bonding of the epitaxial wafer body 9 and the AVG glass body 10, and at the same time control the processing parallelism of the entire fixture to prevent excessive parallelism difference of the products. At the same time, a convex surface in the AVG tray 4 can be used to limit the height of the bonding products to ensure the consistency of the height of the bonding photocathode boss and low deformation. The fixture adopts a component stacking structure. The coaxial constraint of the entire fixture on the axis is achieved by the bonding fixture positioning post 8 and the positioning holes 501 and positioning socket 401 between the components. The perfect cooperation between the components ensures the bonding parallelism. Furthermore, the height limiting effect of the AVG tray 4 and the small parallelism difference effectively ensure the consistency of the bonding height deformation. Finally, compared to traditional bonding fixtures, this bonding fixture, combined with the high-temperature melt bonding process, effectively controls product consistency and significantly improves bonding success rate.
[0052] In this invention, unless otherwise explicitly specified and limited, "above" or "below" the second feature can include direct contact between the first and second features, or contact between the first and second features through another feature between them. Furthermore, "above," "over," and "on top" of the second feature includes the first feature directly above or diagonally above the second feature, or simply indicates that the first feature is at a higher horizontal level than the second feature. "Below," "below," and "under" the second feature includes the first feature directly below or diagonally below the second feature, or simply indicates that the first feature is at a lower horizontal level than the second feature.
[0053] The foregoing has shown and described the basic principles, main features, and advantages of this utility model. Those skilled in the art should understand that this utility model is not limited to the above embodiments. The embodiments and descriptions in the specification are merely preferred examples and are not intended to limit the utility model. Various changes and modifications can be made to this utility model without departing from its spirit and scope, and all such changes and modifications fall within the scope of the claimed utility model. The scope of protection of this utility model is defined by the appended claims and their equivalents.
Claims
1. A low-deformation, high-parallelism fusion-bonded fixture, characterized in that, include: Bonding fixture pressure plate (2), pressure plate limiting plate (3), AVG tray (4), epitaxial wafer limiting plate (5) and bonding fixture base (6). The bonding fixture pressure plate (2) has an integrally formed mounting boss (201) on one side. A steel ball (1) is snapped onto the inner side of the mounting boss (201), and the steel ball (1) has the weight to press down on the bonding fixture pressure plate (2). The pressure plate limiting piece (3) is located on the side of the bonding fixture pressure plate (2) away from the steel ball (1), and the pressure plate limiting piece (3) is used to achieve coaxial positioning. The AVG tray (4) is located on the side of the pressure plate limiting piece (3) away from the bonding fixture pressure plate (2), and the side of the AVG tray (4) close to the pressure plate limiting piece (3) has a concave surface, while the side away from the pressure plate limiting piece (3) has a convex surface. The epitaxial wafer limiting plate (5) is located on the convex side of the AVG tray (4), and the bonding fixture base (6) is sleeved on the outside of the bonding fixture pressure plate (2), the pressure plate limiting plate (3), the AVG tray (4) and the epitaxial wafer limiting plate (5).
2. The low-deformation, high-parallelism fusion bonding fixture according to claim 1, characterized in that: The AVG tray (4) has an AVG glass body (10) placed in the concave side on one side, while the convex side on the other side of the AVG tray (4) serves to ensure parallelism.
3. The low deformation and high parallelism fusion bonding fixture according to claim 1, characterized in that: The inner wall of the bonding fixture base (6) is provided with bonding fixture positioning posts (8) that are snap-fitted and installed at equal intervals, and the number of bonding fixture positioning posts (8) is three.
4. The low deformation and high parallelism fusion bonding fixture according to claim 3, characterized in that: One end of the bonding fixture positioning post (8) passes through the epitaxial wafer limiting plate (5), the AVG tray (4), and the pressure plate limiting plate (3) in sequence.
5. The low deformation and high parallelism fusion bonding fixture according to claim 4, characterized in that: The inner side of the epitaxial wafer limiting disk (5) is provided with positioning holes (501) located on the outer side of the boss and distributed circumferentially, and the positioning holes (501) are used for insertion and positioning with the bonding fixture positioning post (8).
6. The low deformation and high parallelism fusion bonding fixture according to claim 5, characterized in that: The pressure plate limiting piece (3) and the AVG tray (4) are provided with a positioning hole (401) in a circular shape inside, and the positioning hole (401) is used to insert and position with the bonding fixture positioning post (8).
7. A low-deformation, high-parallelism fusion bonding fixture according to claim 6, characterized in that: A spring (7) is sleeved on the surface of the bonding fixture positioning post (8). One end of the spring (7) is engaged with the bonding fixture positioning post (8), and the other end passes through the epitaxial wafer limiting plate (5) to the side of the AVG tray (4) away from the pressure plate limiting plate (3).
8. The low deformation and high parallelism fusion bonding fixture according to claim 1, characterized in that: The epitaxial wafer limiting disk (5) has a boss on the side near the AVG tray (4), and the boss has a recess for limiting and engaging the epitaxial wafer body (9).