JPH10325768A - 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 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 6, 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 in which the pressure sensor chip 1 and the pedestal 6 are housed 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 convex protrusion part 10 is formed at the package 8, and the pedestal 6 is supported by the protrusion part 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. 4 is a schematic configuration diagram 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.

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.

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, the pedestal being fixed, and containing the pressure sensor chip and the pedestal; being electrically connected to the strain gauge resistor and being drawn out of the package; In a semiconductor pressure sensor having an external terminal, a convex projection is provided on the package, and the pedestal is supported by the projection.

According to a second aspect of the present invention, in the semiconductor pressure sensor according to the first aspect, the projection and the pedestal are bonded to each other.

According to a third aspect of the present invention, in the semiconductor pressure sensor according to the first aspect, a side wall portion surrounding the pedestal is provided on the package, and the side wall portion and the pedestal are bonded. Is what you do.

According to a fourth aspect of the present invention, in the semiconductor pressure sensor according to the first aspect, the projection is provided so as to be higher toward the center of the introduction hole, and the projection and the pedestal are bonded. It is characterized by having made it.

[0012]

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.

Reference numeral 10 denotes a convex protrusion formed by processing a portion of the package 8 on which the pedestal 6 is installed into a mountain shape.
Has been fixed. At this time, the pedestal 6 and the package 8 are bonded so that the measured pressure does not leak from between the through hole 7 and the introduction hole 9.

According to the present embodiment, the pedestal 6 is formed by the convex protrusion 10 formed by processing the package 8.
Therefore, the contact area between the pedestal 6 and the package 8 can be made smaller than that of a conventional semiconductor pressure sensor, so that the external force transmitted from the package 8 to the pedestal 6 can be reduced. In addition, when the protrusion 10 is bent, the external force can be further reduced.

FIG. 2 is a schematic configuration diagram of a semiconductor pressure sensor according to another embodiment of the present invention. In the present embodiment, the projection 8 is provided on the package 8 as in the semiconductor pressure sensor shown in FIG. 1, but the package 8 is processed without bonding the pedestal 6 and the projection 10 with the adhesive 11. The side wall part 12 is provided by the adhesive agent 11 and the side wall part 12 and the pedestal 6 are adhered by the adhesive 11. Thereby, the pedestal 6 is fixed to the package 8, and the through hole 7 and the introduction hole 9
To prevent the measured pressure from leaking from between

According to the present embodiment, since the pedestal 6 is supported by the protruding projections 10, the contact area between the pedestal 6 and the package 8 can be reduced as compared with the conventional semiconductor pressure sensor. External force transmitted from the base 8 to the pedestal 6 can be reduced. Further, since the pedestal 6 and the projection 10 are not bonded, the pedestal 6 and the projection 10 are not bonded.
And the side wall 12 is bent,
The external force can be further reduced.

FIG. 3 is a schematic configuration diagram of a semiconductor pressure sensor according to another embodiment of the present invention. In this embodiment, the protrusion 10 is formed by processing the portion of the package 8 to which the pedestal 6 is bonded so that the height increases as the center of the introduction hole 9 approaches.
The adhesive 11 is applied so that the thickness increases as the distance from the center of the introduction hole 9 increases, and the pedestal 6 is bonded to the package 8 such that the pedestal 6 is supported by the tip of the protrusion 10a.

According to the present embodiment, the convex protrusion 10a
As a result, the contact area between the pedestal 6 and the package 8 can be made smaller than that of a conventional semiconductor pressure sensor, so that the external force transmitted from the package 8 to the pedestal 6 can be reduced. Further, the external force propagating from the package 8 to the pedestal 6 can be absorbed by the elasticity of the adhesive 11. Furthermore, since the pedestal 6 and the top of the protrusion 10a formed on the package 8 are bonded so as to be in contact with each other, the thickness of the adhesive 11 can be easily controlled by adjusting the height of the protrusion 10a. .

[0021]

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 and the pedestal, and a strain gauge In a semiconductor pressure sensor having an external terminal electrically connected to a resistor and drawn out of the package, a convex projection is provided on the package, and the pedestal is supported by the projection. The contact area with the package can be reduced compared to the conventional semiconductor pressure sensor, and the external force transmitted from the package to the base can be reduced. Since the ability to be able to provide a semiconductor pressure sensor capable accurately pressure measurement as an external force or the like is applied to the package.

According to the second aspect of the present invention, a first aspect is provided.
In the described invention, since the projection and the pedestal are bonded, the external force transmitted from the package to the pedestal can be further reduced by bending the projection.

According to the third aspect of the present invention, the first aspect is provided.
In the described invention, the side wall surrounding the pedestal is provided on the package, and the side wall and the pedestal are bonded to each other. In addition to being able to be smaller than the conventional semiconductor pressure sensor, the pedestal and the projection are not bonded, and a slip occurs between the pedestal and the projection, and the side wall is bent, External force transmitted from the package to the pedestal can be further reduced.

According to the fourth aspect of the present invention, there is provided the first aspect.
In the described invention, the protrusion is provided so as to be higher toward the center of the introduction hole, and the protrusion and the pedestal are bonded, so that the contact area between the pedestal and the package is smaller than that of the conventional semiconductor pressure sensor. It is possible to reduce the size and to absorb the external force propagating from the package to the pedestal by the elasticity of the adhesive. Further, since the pedestal and the top of the protrusion formed on the package are bonded so as to be in contact with each other, the thickness of the adhesive can be easily controlled by adjusting the height of the protrusion.

[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 conventional semiconductor pressure sensor.

[Description of Signs] 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 Protrusion 11 Adhesive 12 Side wall

Claims (4)

[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 containing the pressure sensor chip and the pedestal; and a package electrically connected to the strain gauge resistor. A semiconductor pressure sensor having an external terminal drawn out of the semiconductor pressure sensor, wherein a convex projection is provided on the package, and the pedestal is supported by the projection. 2. The semiconductor pressure sensor according to claim 1, wherein the projection and the pedestal are bonded to each other. 3. The semiconductor pressure sensor according to claim 1, wherein a side wall surrounding the pedestal is provided on the package, and the side wall and the pedestal are bonded to each other. 4. The semiconductor pressure sensor according to claim 1, wherein the protrusion is provided so as to be higher toward the center of the introduction hole, and the protrusion and the pedestal are bonded.