JPH10325767A - Semiconductor pressure sensor - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a semiconductor pressure sensor by which a pressure can be measured with good accuracy even when an external force or the like is applied to a package. SOLUTION: A sensor is constituted so as to be provided with a pressure sensor chip 1 in which a strain gage resistance 3 whose resistance value is changed according to a pressure change is formed on a thin diaphragm 2, with a pedestal 6 which comprises a through hole 7 communicating with the diaphragm 2 and which supports the pressure sensor chip 1, with a package 8 which comprises an introduction hole 9 used to introduce a pressure, to be measured, into the through hole 7, to which the pedestal 6 is fixed and which houses the pressure sensor chip 1 and with external terminals 5 which are connected electrically to the strain gage resistance 3 and which are derived to the outside of the package 8. In this case, a thin sheetlike springy plate 10 one end of which is fixed to the package 8 is added, the pedestal 8 is installed on the springy plate 10, and the pedestal 6 is suppressed by the elastic force of the springy plate 10.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a semiconductor pressure sensor for detecting pressure using a diaphragm.

[0002]

2. Description of the Related Art FIG. 5 is a schematic structural view of a conventional semiconductor pressure sensor. Reference numeral 1 denotes a pressure sensor chip, and a strain gauge resistor 3 whose resistance value changes in accordance with a change in pressure is formed on a thin diaphragm 2. The strain gauge resistor 3 is connected to an external terminal 5 by a wire 4.

A pedestal 6 made of glass or the like is joined to the pressure sensor chip 1 by anodic bonding or the like, and supports the pressure sensor chip 1. The pedestal 6 is provided with a through-hole 7 communicating with the diaphragm 2.

A package 8 houses the pressure sensor chip 1 and the pedestal 6. The package 8 has an introduction hole 9 for introducing a measured pressure into the through hole 7 of the pedestal 6.

In the semiconductor pressure sensor having the above-described structure, the pressure-receiving resistance is changed from the introduction hole 9 of the package 8 to the through hole 7 of the base 6.
Applied to the diaphragm 2 via the
Is measured in accordance with the measured pressure, and the strain is electrically detected by the strain gauge resistor 3 to measure the measured pressure.

[0006]

However, in the semiconductor pressure sensor having the above-described structure, when an external force or the like is applied to the package 8, the diaphragm 2 is distorted by the external force, so that accurate pressure measurement cannot be performed. There was a problem that can not be.

The present invention has been made in view of the above points, and an object of the present invention is to provide a semiconductor pressure sensor capable of accurately measuring pressure even when an external force or the like is applied to a package. It is in.

[0008]

According to the first aspect of the present invention,
A pressure sensor chip formed on a thin diaphragm having a strain gauge resistance whose resistance value changes in accordance with a pressure change, a pedestal having a through hole communicating with the diaphragm and supporting the pressure sensor chip; A package having an introduction hole for introducing a pressure to be measured into the hole and accommodating the pressure sensor chip, wherein the pedestal is fixed, and an external terminal which is electrically connected to the strain gauge resistor and drawn out of the package. In the semiconductor pressure sensor having a thin plate-like spring-like plate having one end fixed to the package, the pedestal is provided on the spring-like plate, and the pedestal is supported by the elastic force of the spring-like plate. It is something to do.

According to a second aspect of the present invention, in the semiconductor pressure sensor according to the first aspect, the spring-like plate is formed by processing a package.

According to a third aspect of the present invention, in the semiconductor pressure sensor according to the first aspect, the spring-like plate is formed of the same material as the external terminals.

[0011]

DESCRIPTION OF THE PREFERRED EMBODIMENTS One embodiment of the present invention will be described below with reference to the drawings. FIG. 1 is a schematic configuration diagram of a semiconductor pressure sensor according to one embodiment of the present invention. Reference numeral 1 denotes a pressure sensor chip, and a strain gauge resistor 3 whose resistance value changes in accordance with a change in pressure is formed on a thin diaphragm 2.

The strain gauge resistor 3 is connected to an external terminal 5 by a wire 4. The material of the external terminal 5 is copper, Kovar, stainless spring steel, 42 alloy, or the like, and it is desirable that the surface is plated with gold, silver, or the like from the viewpoint of moisture resistance and oxidation prevention.

Reference numeral 6 denotes a pedestal formed of glass or the like, which is joined to the pressure sensor chip 1 by anodic bonding or the like and supports the pressure sensor chip 1. The pedestal 6 is provided with a through-hole 7 communicating with the diaphragm 2.

Reference numeral 8 denotes a package formed of plastic or the like, which houses the pressure sensor chip 1 and the pedestal 6. The package 8 has an introduction hole 9 for introducing a measured pressure into the through hole 7 of the pedestal 6.

Reference numeral 10 denotes a thin spring-like plate, one end of which is fixed to the package 8. The pedestal 6 is provided on the spring-like plate 10 with an adhesive 11 such as a low-stress silicone resin or epoxy resin.
And supported by the elastic force of the spring-shaped plate 10. When an external force is applied to the package 8, the spring-like plate bends, so that the external force propagating to the diaphragm 2 via the pedestal 6 is reduced. The spring-shaped plate 10 may have any shape as long as it has a shape that bends against an external force applied to the package 8, and the material is not particularly limited.

According to this embodiment, when an external force is applied to the package 8, the spring-like plate 10 bends, so that the external force propagating to the pressure sensor chip 1 can be reduced.

FIG. 2 is a schematic configuration diagram of a semiconductor pressure sensor according to another embodiment of the present invention. In this embodiment, a thin spring-like plate 10a is formed by processing the package 8 so as to project toward the center of the introduction hole 9,
The pedestal 6 is adhered thereon.

As shown in FIG. 3, the spring-like plate 10b is formed by processing the package 8 so as to protrude outward from the center of the introduction hole 9, and the pedestal 6 is bonded thereon. It may be.

According to the present embodiment, the spring-like plate 10a (or the spring-like plate 10b) can be formed simultaneously with the package 8, so that the spring-like plate 10a (or the spring-like plate 10a) is formed.
The spring-shaped plate 10b) can be easily formed.

FIG. 4 is a schematic configuration diagram of a semiconductor pressure sensor according to another embodiment of the present invention. In the present embodiment, a thin plate-like spring-like plate 10c is provided so as to project toward the center of the introduction hole 9 using the same material as the external terminal 5, and the pedestal 6 is adhered thereon. . At this time, it is desirable that the material forming the spring-like plate 10c has a small thermal expansion coefficient.

According to the present embodiment, since the spring-like plate 10c is made of the same material as the external terminal 5, it can be formed simultaneously with the external terminal 5. In addition, the pressure sensor chip 1
The spring-like plate 10c can be used as a ground wire when grounding the pedestal 6 and the package 8 to the package 8.

[0022]

As described above, according to the first aspect of the present invention, there is provided a pressure sensor chip formed on a thin diaphragm with a strain gauge resistor whose resistance value changes according to a pressure change. A pedestal having a through hole communicating with the diaphragm and supporting the pressure sensor chip, a package having an introduction hole for introducing a measured pressure into the through hole, the pedestal being fixed and accommodating the pressure sensor chip, a strain gauge resistor, An external terminal electrically connected and drawn out of the package, the semiconductor pressure sensor comprising:
A thin spring plate with one end fixed to the package is added, a pedestal is provided on the spring plate, and the pedestal is supported by the elastic force of the spring plate, so that when an external force is applied to the package, An external force applied to the pressure sensor chip can be reduced by bending the spring-shaped plate, and a semiconductor pressure sensor capable of accurately measuring pressure even when an external force or the like is applied to a package can be provided. Was.

According to the second aspect of the present invention, there is provided the first aspect.
In the described invention, the spring-like plate is formed by processing the package, so that the spring-like plate can be formed simultaneously with the package.

According to the third aspect of the present invention, there is provided the first aspect.
In the described invention, the spring-like plate is formed of the same material as the external terminal, so that the spring-like plate can be formed simultaneously with the external terminal. In addition, the spring-like plate can be used as a ground wire when grounding the pressure sensor chip or the pedestal and the package.

[Brief description of the drawings]

FIG. 1 is a schematic configuration diagram of a semiconductor pressure sensor according to an embodiment of the present invention.

FIG. 2 is a schematic configuration diagram of a semiconductor pressure sensor according to another embodiment of the present invention.

FIG. 3 is a schematic configuration diagram of a semiconductor pressure sensor according to another embodiment of the present invention.

FIG. 4 is a schematic configuration diagram of a semiconductor pressure sensor according to another embodiment of the present invention.

FIG. 5 is a schematic configuration diagram of a conventional semiconductor pressure sensor.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Pressure sensor chip 2 Diaphragm 3 Strain gauge resistance 4 Wire 5 External terminal 6 Pedestal 7 Through hole 8 Package 9 Introducing hole 10 Spring plate 11 Adhesive

Claims (3)

[Claims] 1. A pressure sensor chip formed by forming a strain gauge resistor whose resistance value changes according to a pressure change on a thin diaphragm, and a through hole communicating with the diaphragm to support the pressure sensor chip. A pedestal, a package having an introduction hole for introducing a pressure to be measured into the through hole, the pedestal being fixed, and a package accommodating the pressure sensor chip, and being electrically connected to the strain gauge resistor and being outside the package. A semiconductor pressure sensor having an external terminal to be drawn out, a thin spring-shaped plate having one end fixed to the package, a pedestal provided on the spring-shaped plate, and an elastic force of the spring-shaped plate. Wherein the pedestal is supported by the semiconductor pressure sensor. 2. The package according to claim 1, wherein said spring-like plate is formed by processing a package.
A semiconductor pressure sensor according to claim 1. 3. The semiconductor pressure sensor according to claim 1, wherein said spring-like plate is formed of the same material as said external terminals.