阅读说明：本技术 一种低应力效应硅压传感器模块 (Low stress effect silicon pressure sensor module ) 是由 王东平 李正 于 2020-08-07 设计创作，主要内容包括：本发明公开了一种低应力效应硅压传感器模块,包括壳体,壳体内装有传感器芯片和电路芯片,还包括金属片,金属片伸入壳体中,壳体设有贯通的空腔,空腔包括A面和B面,A面靠近气孔,电路芯片通过低膨胀系数的硅胶固定在金属片朝向B面的一侧,传感器芯片通过低膨胀系数的金属胶固定在电路芯片朝向A面的一侧,壳体内全部涂覆有保护凝胶将金属片、电路芯片和传感器芯片进行包覆。壳体中是空腔,电路芯片仅靠金属片作为支撑点,无多余的塑料依附,具有在不同温度条件下的抵抗应力特性。电路芯片和金属片、传感器芯片和电路芯片之间均通过低膨胀系数的胶进行固定,环境温度升高时,受热膨胀幅度小,且两者膨胀方向相反,达到减小应力的影响。(The invention discloses a low stress effect silicon pressure sensor module, which comprises a shell, wherein a sensor chip and a circuit chip are arranged in the shell, the low stress effect silicon pressure sensor module also comprises a metal sheet, the metal sheet extends into the shell, the shell is provided with a through cavity, the cavity comprises an A surface and a B surface, the A surface is close to an air hole, the circuit chip is fixed on one side of the metal sheet facing the B surface through low-expansion-coefficient silica gel, the sensor chip is fixed on one side of the circuit chip facing the A surface through low-expansion-coefficient metal gel, and the metal sheet, the circuit chip and the sensor chip are coated by protective gel which is completely coated in the shell. The cavity is arranged in the shell, the circuit chip only uses the metal sheet as a supporting point, no redundant plastic is attached, and the circuit chip has the stress resistance characteristic under different temperature conditions. All fix through the glue of low expansion coefficient between circuit chip and the sheetmetal, sensor chip and the circuit chip, when ambient temperature risees, the thermal expansion range is little, and both expansion directions are opposite, reach the influence that reduces stress.)

1. The utility model provides a low stress effect silicon pressure sensor module, which comprises a housin, be equipped with sensor chip and circuit chip in the casing, a serial communication port, still include the sheetmetal, the sheetmetal stretches into in the casing, the casing is equipped with the cavity that link up, the cavity includes A face and B face, the A face is close to the gas pocket, the circuit chip is fixed in one side of sheetmetal orientation B face through the silica gel of low expansion coefficient, the sensor chip is fixed in one side of circuit chip orientation A face through the metal gel of low expansion coefficient, whole coatings have the protection gel in the casing with the sheetmetal, circuit chip and sensor chip carry out the cladding.

2. The low stress effect silicon pressure sensor module of claim 1, wherein the coefficient of expansion of the silicone rubber is greater than the coefficient of expansion of the metal rubber.

3. The low stress effect silicon pressure sensor module of claim 1, wherein the protective gel is generic or has acid, base, oil resistant properties.

4. The low stress effect silicon pressure sensor module of claim 1, wherein the housing is provided with a molded step on each of the a-side and the B-side of the cavity.

5. The low stress effect silicon pressure sensor module of claim 1, wherein the two metal plates extend into the housing from the left and right sides of the housing, the two ends of the circuit chip are fixed to the two metal plates, and the sensor chip is located between the two metal plates.

Technical Field

The invention belongs to the technical field of sensors, and particularly relates to a silicon pressure sensor.

Background

The silicon pressure sensor manufactured by adopting the MEMS process has the characteristics of simple structure, high sensitivity, high reliability and the like, and is widely used for pressure monitoring and data acquisition under various environments, but the existing silicon pressure sensor is limited to volume and structural design, and generates stress on the material of the silicon pressure sensor due to the external acting force and expansion or contraction during high and low temperature changes.

There are two solutions for stress improvement in currently common silicon pressure sensors:

one is to use low expansion, high seal sheet materials such as ceramics, sheet metal.

And secondly, selecting the silica gel with low hardness coefficient as the connection between the platform and the silicon pressure chip, and utilizing the extension characteristic of the silica gel to play a certain improvement role.

The common defects of the two schemes are that the process structure is complex, multiple combinations are used simultaneously, and the product performance cannot meet the market of micro-pressure measurement or high-precision requirements due to the unmatched expansion coefficients.

Disclosure of Invention

In order to solve the above problems, the present invention provides the following technical solutions: the utility model provides a sensor module is pressed to low stress effect silicon, which comprises a housin, be equipped with sensor chip and circuit chip in the casing, still include the sheetmetal, the sheetmetal stretches into in the casing, the casing is equipped with the cavity that link up, the cavity includes A face and B face, the A face is close to the gas pocket, the circuit chip is fixed in the one side of sheetmetal orientation B face through the silica gel of low expansion coefficient, the sensor chip is fixed in the one side of circuit chip orientation A face through the metal adhesive of low expansion coefficient, the whole coatings in the casing have the protection gel with the sheetmetal, circuit chip and sensor chip carry out the cladding.

The cavity is arranged in the shell, the circuit chip only depends on the metal sheet as a supporting point, no redundant plastic is attached, and compared with the traditional structure, the circuit chip has the stress resistance characteristic under different temperature conditions. All fix through the glue of low expansion coefficient between circuit chip and the sheetmetal, sensor chip and the circuit chip, when ambient temperature risees, the thermal expansion range is little, and both expansion directions are opposite, reach the influence that reduces stress. The protective gel then serves to protect the internal devices.

Furthermore, the expansion coefficient of the silica gel is larger than that of the metal gel. In this case, when the ambient temperature rises, the pressure applied to the upper side of the sensor chip will tend to decrease with the expansion of the silica gel, so as to reduce the influence of stress.

Further, the protective gel is general or has acid, alkali and oil resistance. The general protective gel is suitable for the environment without special requirements, and the protective gel with acid, alkali and oil resistance is suitable for the special environment.

Furthermore, the shell is provided with molding steps on the surface A and the surface B of the cavity respectively, so that the molding of the gel is protected conveniently.

Furthermore, the metal sheets comprise two metal sheets which extend into the shell from the left side and the right side of the shell respectively, two ends of the circuit chip are fixed with the two metal sheets respectively, and the sensor chip is positioned between the two metal sheets.

Drawings

In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the drawings required to be used in the description of the embodiments are briefly introduced below, the drawings in the following description are only some embodiments of the present invention, and it is obvious for those skilled in the art that other drawings can be obtained according to the drawings without creative efforts.

FIG. 1 is a schematic view of the structure of the present invention.

Detailed Description

The above-described scheme is further illustrated below with reference to specific examples. It should be understood that these examples are for illustrative purposes and are not intended to limit the scope of the present invention. The conditions used in the examples may be further adjusted according to the conditions of the particular manufacturer, and the conditions not specified are generally the conditions in routine experiments.

As shown in fig. 1, a low stress effect silicon pressure sensor module, including casing 1, sensor chip 2 and circuit chip 3 are equipped with in the casing 1, still include sheetmetal 4, sheetmetal 4 stretches into in the casing 1, casing 1 is equipped with the cavity that link up, the cavity includes A face 5 and B face 6, A face 6 is close to the gas pocket, circuit chip 3 is fixed in sheetmetal 4 one side towards B face 6 through low expansion coefficient's silica gel 9, sensor chip 2 fixes in circuit chip 3 one side towards A face 5 through low expansion coefficient's metal adhesive 10, the whole coating has protection gel 11 in the casing 1 to carry out the cladding with sheetmetal 4, circuit chip 3 and sensor chip 2. The shell 1 is provided with molding steps on the surface A5 and the surface B6 of the cavity respectively, namely a molding step 7 and a molding step 8 on the surface A and the surface B, so that the molding of gel is protected conveniently. The metal sheets 4 comprise two metal sheets and extend into the shell 1 from the left side and the right side of the shell 1 respectively, the two ends of the circuit chip 3 are fixed with the two metal sheets 4 respectively, and the sensor chip 2 is positioned between the two metal sheets 4.

Preferably, the expansion coefficient of the silica gel is greater than that of the metal gel.

Preferably, the protective gel 11 is generic or has acid, base, oil resistant properties.

The above examples are only for illustrating the technical idea and features of the present invention, and the purpose of the present invention is to enable those skilled in the art to understand the content of the present invention and implement the present invention, and not to limit the protection scope of the present invention. All equivalent changes and modifications made according to the spirit of the present invention should be covered within the protection scope of the present invention.