A high-temperature-resistant pressure sensor chip packaging clamp
By designing a graphite clamp, the pressure sensor chip was able to be stably bonded and vibration-resistant in a high-temperature environment, solving the problem of low yield in the packaging process and improving the feasibility of large-scale mass production.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- CHENGDU BEIXIN SENSOR TECH CO LTD
- Filing Date
- 2025-07-29
- Publication Date
- 2026-05-29
AI Technical Summary
Existing pressure sensor chip packaging technology is prone to breakage and has poor vibration resistance in high-temperature environments, and the yield rate of leadless packaging technology is low, making large-scale mass production difficult.
The upper and lower clamps are made of graphite. Through the design and coordination of the clamps, a stable fit is achieved between the expanded alloy shell and the glass substrate and chip. A reducing atmosphere is provided to prevent oxidation, and the packaging stability and yield are improved through the guiding and limiting structure.
This improved the sintering yield of leadless packages, enhanced the stability and vibration resistance of pressure sensor chips in high-temperature environments, and ensured the robustness and reliability of the package.
Smart Images
Figure CN224295716U_ABST
Abstract
Description
Technical Field
[0001] This utility model relates to the field of pressure sensor technology, specifically to a high-temperature resistant pressure sensor chip packaging fixture. Background Technology
[0002] Currently, pressure sensor chips typically employ wire bonding packaging, connecting the chip electrodes to external pins via gold or aluminum wires. However, this packaging process has significant drawbacks. On one hand, gold wires are prone to embrittlement and breakage at high temperatures, making pressure sensor chips produced using this packaging process generally unable to withstand high-temperature environments. On the other hand, the wires are susceptible to fatigue fracture in mechanical vibration scenarios, resulting in poor vibration resistance for the pressure sensor chips.
[0003] To address the shortcomings of the aforementioned packaging processes, a leadless packaging process also exists. While pressure sensor chips produced using this leadless packaging process exhibit good vibration resistance and high-temperature resistance, their low yield rate makes large-scale mass production difficult. Therefore, improving the sintering yield of leadless packaging is a pressing technical problem that needs to be solved. Utility Model Content
[0004] The purpose of this invention is to address the problems of low sintering yield and difficulty in large-scale mass production of pressure sensor chips using leadless packaging technology. This invention provides a high-temperature resistant pressure sensor chip packaging fixture to improve the sintering yield of leadless packaging.
[0005] To achieve the above-mentioned objectives, this utility model provides the following technical solution:
[0006] A high-temperature pressure sensor chip packaging fixture includes an upper fixture and a lower fixture. The upper fixture includes an upper clamping part, which has a first placement groove for placing and holding an expansion alloy shell. The expansion alloy shell is used to connect to a glass substrate. The lower fixture is used to limit the chip. The upper and lower fixtures cooperate to act on the expansion alloy shell and the chip, so that the first placement groove can push against the expansion alloy shell, thereby pressing and bonding the glass substrate with the chip in a molten state.
[0007] Both the upper and lower clamps are made of graphite, and part of the upper clamp is made of elastic graphite so that the heated expansion alloy shell can expand in both the lateral and longitudinal directions.
[0008] As a preferred technical solution of this application, the upper clamp further includes two upper clamp parts, and a first step is formed on the two upper clamp parts. The first step is used to abut against the first upper clamp part, so that the two upper clamp parts can apply a force towards the lower clamp to the first upper clamp part.
[0009] As the preferred technical solution of this application, the two upper clamps are made of hard graphite, the first upper clamp has a cylindrical structure, and the inner side of the two upper clamps fits against the outer side of the first upper clamp.
[0010] As the preferred technical solution of this application, the upper clamp part is conical, and the upper clamp part is provided with an inclined surface, which contacts the outer side of the upper clamp part.
[0011] As the preferred technical solution of this application, the upper clamp is provided with a guide groove, and the lower clamp is provided with a guide post. The guide post is made of graphite. The guide groove is adapted to the guide post, and the guide post can move in the guide groove so that the upper clamp can move relative to the lower clamp along the central axis of the upper clamp.
[0012] As the preferred technical solution of this application, the lower fixture is provided with a placement stage, the placement stage is made of graphite, and a limiting groove is provided on the placement stage. The limiting groove is adapted to the chip and is used to place the chip and limit the chip.
[0013] The placement platform protrudes from the guide post.
[0014] As the preferred technical solution of this application, the depth of the guide groove is α, the height of the guide post is β, and α > β.
[0015] As a preferred technical solution of this application, when the upper clamp and the lower clamp compress the expansion alloy shell, the glass base and the chip, there is a gap θ between the lower side of a portion of the upper clamp and the lower clamp, wherein θ > 0.
[0016] Compared with the prior art, the beneficial effects of this utility model are as follows:
[0017] 1. In the solution of this application, the first placement groove on the upper clamp holds and clamps the expansion alloy shell. With the lower clamp limiting the chip, during leadless sintering of the chip, the upper and lower clamps cooperate to act on the expansion alloy shell and the chip. When the glass substrate melts, the first placement groove pushes against the expansion alloy shell, causing the glass substrate and the chip to press and adhere together. During this process, since the upper clamp is made of elastic graphite, under high-temperature conditions, when the expansion alloy shell expands along its transverse and longitudinal directions, the upper clamp can adapt to the expansion alloy shell. This process not only prevents deformation but also further enhances the stability of the expansion alloy shell and the upper clamp, thus preventing damage to the expansion alloy shell. Furthermore, using graphite for the upper and lower clamps prevents the glass from sticking to the clamps after melting, facilitating the separation of the packaged chip from the clamps. Graphite also provides a reducing atmosphere to prevent oxidation of the expansion alloy. In addition, the cooperation of the upper and lower clamps prevents the glass base from melting and tilting. This further improves the yield of leadless sintering, making the sintered pressure sensor chip more stable and reliable.
[0018] 2. Furthermore, the two upper clamps are made of hard graphite. When the expansion alloy shell expands, the two upper clamps can constrain the deformation of the first upper clamp, thereby improving the stability of the relative position between the first and second upper clamps. This facilitates the expansion of the expansion alloy shell due to temperature rise, and also helps maintain the relative position between the expansion alloy shell, the glass substrate, and the chip, thereby improving the stability of the chip packaging.
[0019] 3. Furthermore, the upper clamp is cone-shaped and has an inclined surface on the upper clamp. The inclined surface faces the lower clamp. During the chip packaging process, the inclined surface contacts the outer side of the upper clamp. After the expansion alloy shell expands laterally, the expansion alloy shell abuts against the upper clamp and the upper clamp abuts against the inclined surface. The inclined surface acts as a guide, so that the upper clamp tends to move towards the lower clamp. Under the action of the first placement groove on the upper clamp pushing the expansion alloy shell, the stability of the glass base and chip extrusion bonding can be further enhanced.
[0020] 4. Furthermore, the depth of the guide groove is greater than the height of the guide post, and the gap θ between the upper clamp and the lower clamp is greater than 0. When the guide groove and the guide post are engaged, it can prevent the guide post from abutting against the guide groove, leaving space in the guide groove so that the expansion alloy shell can be placed into the first placement groove. The space left in the guide groove can prevent the two ends of the expansion alloy shell from being squeezed at the same time, which can effectively prevent the expansion alloy shell from being damaged. This further enhances the fit between the expansion alloy shell and the guide groove, facilitates sintering, and thus improves the sintering yield. Attached Figure Description
[0021] Figure 1 This is a schematic diagram of the structure of a high-temperature pressure sensor chip packaging fixture according to one embodiment of the present application, which includes an expansion alloy shell, a glass base, a chip, and pins.
[0022] Figure 2 This is an exploded structural diagram of one embodiment of a high-temperature pressure sensor chip packaging fixture according to this application.
[0023] Figure 3 This is a partial structural schematic diagram of one embodiment of a high-temperature pressure sensor chip packaging fixture according to this application;
[0024] The diagram shows: 1-Upper clamp, 2-Lower clamp, 3-Upper clamp part 1, 4-First placement groove, 5-Expansion alloy shell, 6-Glass base, 7-Chip, 8-Upper clamp part 2, 9-First step, 10-Inclined surface, 11-Guide groove, 12-Guide post, 13-Placement stage, 14-Limiting groove, 15-Pin. Detailed Implementation
[0025] To make the objectives, technical solutions, and advantages of the embodiments of this utility model clearer, the technical solutions of the embodiments of this utility model will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some, not all, of the embodiments of this utility model.
[0026] Therefore, the following detailed description of the embodiments of this utility model is not intended to limit the scope of the claimed utility model, but merely to illustrate some embodiments of the utility model. All other embodiments obtained by those skilled in the art based on the embodiments of this utility model without inventive effort are within the scope of protection of this utility model.
[0027] It should be noted that, unless otherwise specified, the embodiments and features and technical solutions in the present invention can be combined with each other.
[0028] It should be noted that similar labels and letters in the following figures indicate similar items. Therefore, once an item is defined in one figure, it does not need to be further defined and explained in subsequent figures.
[0029] In the description of this utility model, it should be noted that the terms "upper," "lower," etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings, or the orientation or positional relationship commonly used when the product of this utility model is in use, or the orientation or positional relationship commonly understood by those skilled in the art. These terms are only for the convenience of describing this utility model and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation on this utility model. In addition, the terms "first," "second," etc., are only used to distinguish descriptions and should not be construed as indicating or implying relative importance.
[0030] Example 1: This example provides a high-temperature resistant pressure sensor chip packaging fixture, see [link / reference]. Figure 1 and Figure 2 As shown, it includes an upper clamp 1 and a lower clamp 2. The upper clamp 1 includes an upper clamp part 3, which forms a first placement groove 4. The first placement groove 4 is used to place and hold the expansion alloy shell 5. The expansion alloy shell 5 is used to connect with the glass base 6. The lower clamp 2 is used to limit the chip 7. The upper clamp 1 and the lower clamp 2 cooperate to act on the expansion alloy shell 5 and the chip 7, so that the first placement groove 4 can push against the expansion alloy shell 5, thereby pressing and bonding the glass base 6 with the chip 7 in a molten state.
[0031] Both the upper clamp 1 and the lower clamp 2 are made of graphite, and part of the upper clamp 3 is made of elastic graphite so that the heated expansion alloy shell 5 can expand in both the horizontal and vertical directions.
[0032] In this application, the first placement groove 4 on the upper clamp 3 holds and clamps the expansion alloy shell 5. With the lower clamp 2 limiting the chip 7, during leadless sintering of the chip 7, the upper clamp 1 and lower clamp 2 cooperate to act on the expansion alloy shell 5 and the chip 7. This allows the first placement groove 4 to push against the expansion alloy shell 5 when the glass substrate 6 melts, causing the glass substrate 6 and the chip 7 to press and adhere together. During this process, since the upper clamp 3 is made of elastic graphite, it can adapt to the expansion alloy shell 5 as it expands laterally and longitudinally under high-temperature conditions. 5. Deformation occurs, and the stability of the expansion alloy shell 5 and the upper clamp 3 is further improved, thus preventing damage to the expansion alloy shell 5. At the same time, the use of graphite material for the upper clamp 1 and the lower clamp 2 can prevent the glass from sticking to the upper clamp 1 or the lower clamp 2 after melting, making it easier to separate the packaged chip 7 from the clamp. In addition, graphite can provide a reducing atmosphere to prevent oxidation of the expansion alloy. At the same time, with the cooperation of the upper clamp 1 and the lower clamp 2, the glass base 6 can be prevented from melting and tilting. Thus, the yield of leadless sintering is further improved, making the sintered pressure sensor chip more stable and reliable.
[0033] Meanwhile, when using the fixture of this application to package the chip 7, the upper fixture part 3 is placed in an inert atmosphere or vacuum environment, that is, the fixture is placed in a closed environment, and an inert gas is filled into the closed environment or the closed environment is made into a vacuum state, so as to ensure the stability of the upper fixture part 3 in a high temperature environment.
[0034] In a preferred embodiment, based on the above method, the upper clamp 1 further includes an upper clamp second part 8, on which a first step 9 is formed. The first step 9 is used to abut against the upper clamp first part 3 so that the upper clamp second part 8 can apply a force toward the lower clamp 2 to the upper clamp first part 3.
[0035] Furthermore, by setting a first step 9, which is used to abut against the upper clamp part 3, the upper clamp part 8 applies a force towards the lower clamp 2 to the upper clamp part 3, so that the glass base 6 and the chip 7 are pressed and bonded together.
[0036] As a preferred embodiment, based on the above method, the upper clamping part 8 is made of hard graphite, the upper clamping part 3 has a cylindrical structure, and the inner side of the upper clamping part 8 is in contact with the outer side of the upper clamping part 3.
[0037] Furthermore, the upper clamping part 8 is made of hard graphite. When the expansion alloy shell 5 expands, the upper clamping part 8 can constrain the deformation of the upper clamping part 3, thereby improving the stability of the relative position between the upper clamping part 3 and the upper clamping part 8. This also facilitates the maintenance of the relative position between the expansion alloy shell 5, the glass substrate 6, and the chip 7 when the expansion alloy shell 5 expands due to temperature rise, thus improving the stability of the chip 7 packaging.
[0038] As a preferred embodiment, based on the above method, the upper clamp part 3 is conical, and the upper clamp part 8 is provided with an inclined surface 10, which contacts the outer side surface of the upper clamp part 3.
[0039] Furthermore, the upper clamp part 3 is cone-shaped, and an inclined surface 10 is provided on the upper clamp part 8, with the inclined surface 10 facing the lower clamp 2. During the chip 7 packaging process, the inclined surface 10 contacts the outer side of the upper clamp part 3. After the expansion alloy shell 5 expands laterally, the expansion alloy shell 5 abuts against the upper clamp part 3, and the upper clamp part 3 abuts against the inclined surface 10. The inclined surface 10 plays a guiding role, so that the upper clamp part 3 has a tendency to move towards the lower clamp 2. Under the action of the first placement groove 4 on the upper clamp part 3 pushing against the expansion alloy shell 5, the stability of the glass base 6 and the chip 7 being squeezed and bonded can be further enhanced.
[0040] Example 2: Based on the technical solution of Example 1, further details are provided below. Figures 1-3 As shown, the upper clamp 2 is provided with a guide groove 11, and the lower clamp 2 is provided with a guide post 12. The guide post 12 is made of graphite. The guide groove 11 and the guide post 12 are adapted to each other. The guide post 12 can move in the guide groove 11 so that the upper clamp 1 can move relative to the lower clamp 2 along the central axis of the upper clamp 1.
[0041] Furthermore, by setting the guide groove 11 and guide post 12, when the glass substrate 6 and the chip 7 are engaged, the direction of movement of the glass substrate 6 relative to the chip 7 can be limited, so that the glass substrate 6 moves towards the chip 7, thereby facilitating the glass substrate 6 to squeeze the chip 7, thereby improving the sintering yield of the chip 7 package.
[0042] As a preferred embodiment, based on the above method, the lower clamp 2 is further provided with a placement stage 13, the placement stage 13 is made of graphite, the placement stage 13 is provided with a limiting groove 14, the limiting groove 14 is adapted to the chip 7, and the limiting groove 14 is used to place the chip 7 and limit the chip 7.
[0043] The placement platform 13 protrudes from the guide post 12.
[0044] Furthermore, by setting up a placement stage 13 to limit the position of the chip 7, the stability of the relative position between the chip 7 and the lower clamp 2 is improved.
[0045] In a preferred embodiment, based on the above method, the depth of the guide groove 11 is α, the height of the guide post 12 is β, and α > β.
[0046] In a preferred embodiment, based on the above method, when the upper clamp 1 and the lower clamp 2 compress the expansion alloy shell 5, the glass base 6 and the chip 7, there is a gap θ between the lower side of the upper clamp part 3 and the lower clamp 2, wherein θ > 0.
[0047] Furthermore, the depth of the guide groove 11 is greater than the height of the guide post 12, and the gap θ between the upper clamp 3 and the lower clamp 2 is greater than 0. When the guide groove 11 and the guide post 12 are engaged, it can prevent the guide post 12 from abutting against the guide groove 11, so that there is space in the guide groove 11 so that the expansion alloy shell 5 can be placed into the first placement groove 4. The space left in the guide groove 11 can accommodate the expansion alloy shell 5 being squeezed at both ends at the same time, which can effectively prevent the expansion alloy shell 5 from being damaged. This further enhances the fit between the expansion alloy shell 5 and the guide groove 11, facilitates sintering, and thus improves the sintering yield.
[0048] Furthermore, the upper clamp 1 is made to be through-hole so that when the expansion alloy shell 5 is held in the first placement groove 4, the pin 15 on the glass base 6 can pass through the upper clamp 1, so that the upper clamp 1 can be adapted to pins 15 of different lengths, thereby improving the compatibility between the glass base 6 and the upper clamp 1, and thus facilitating sintering.
[0049] The above embodiments are only used to illustrate the present utility model and are not intended to limit the technical solutions described in the present utility model. Although the present utility model has been described in detail with reference to the above embodiments, the present utility model is not limited to the specific embodiments described above. Therefore, any modifications or equivalent substitutions to the present utility model, and all technical solutions and improvements that do not depart from the spirit and scope of the utility model, are covered within the scope of the claims of the present utility model.
Claims
1. A high-temperature resistant pressure sensor chip packaging fixture, characterized in that: The device includes an upper clamp and a lower clamp. The upper clamp includes an upper clamp part, which has a first placement groove. The first placement groove is used to place and hold the expansion alloy shell. The expansion alloy shell is used to connect with the glass substrate. The lower clamp is used to limit the chip. The upper clamp and the lower clamp work together to act on the expansion alloy shell and the chip, so that the first placement groove can push against the expansion alloy shell, thereby pressing and bonding the glass substrate with the chip in a molten state. Both the upper and lower clamps are made of graphite, and part of the upper clamp is made of elastic graphite so that the heated expansion alloy shell can expand in both the lateral and longitudinal directions.
2. The high-temperature pressure sensor chip packaging fixture as described in claim 1, characterized in that: The upper clamp also includes two upper clamp parts, each with a first step. The first step is used to abut against one upper clamp part, so that the two upper clamp parts can apply a force toward the lower clamp part to the upper clamp part.
3. The high-temperature pressure sensor chip packaging fixture as described in claim 2, characterized in that: The two upper clamps are made of hard graphite, and the first upper clamp has a cylindrical structure. The inner side of the two upper clamps fits against the outer side of the first upper clamp.
4. The high-temperature pressure sensor chip packaging fixture as described in claim 3, characterized in that: The upper clamp has a cone-shaped part and an inclined surface on the second part, which is in contact with the outer side of the upper clamp.
5. The high-temperature pressure sensor chip packaging fixture as described in claim 4, characterized in that: The upper clamp is provided with guide grooves on both parts, and the lower clamp is provided with guide posts. The guide posts are made of graphite. The guide grooves are adapted to the guide posts, and the guide posts can move within the guide grooves so that the upper clamp can move relative to the lower clamp along the central axis of the upper clamp.
6. The high-temperature pressure sensor chip packaging fixture as described in claim 5, characterized in that: The lower fixture is provided with a placement platform, which is made of graphite. The placement platform is provided with a limiting groove, which is adapted to the chip. The limiting groove is used to place the chip and limit the chip's position. The placement platform protrudes from the guide post.
7. The high-temperature pressure sensor chip packaging fixture as described in claim 6, characterized in that: The depth of the guide groove is α, and the height of the guide post is β, wherein α > β.
8. The high-temperature pressure sensor chip packaging fixture as described in claim 7, characterized in that: When the upper and lower clamps compress the expansion alloy shell, glass base and chip, there is a gap θ between the lower side of a portion of the upper clamp and the lower clamp, where θ > 0.