JP2004354294A - Pressure sensor - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a miniaturized semiconductor pressure sensor having high temperature responsiveness and airtightness, capable of measuring also a temperature simultaneously. <P>SOLUTION: A thermistor 18 for temperature measurement and a terminal 8 for connection to the outside are welded and fixed beforehand on a pipe set 10, and while forming a connector 15 for connection to the outside and a fixing flange 23, the pipe set 10 is covered with a synthetic resin, to thereby form a storage case 14 of a semiconductor gage case set 1. The semiconductor gage case set 1 is welded on the terminal 8 for connection to the outside in the case 14, and an epoxy resin 17 for airtight sealing is filled and hardened, to thereby acquire this semiconductor pressure sensor. In the sensor, the number of components or the assembling man-hour can be greatly reduced, and the armoring case has a small-sized seamless structure. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to a pressure sensor, and particularly to a semiconductor pressure sensor integrated with a temperature sensor.
[0002]
[Prior art]
A conventional method for maintaining the airtightness of a terminal portion of a pressure sensor, as described in Patent Literature 1, uses a protective member such as a gel when a metal lead material is insert-molded with an organic resin material or the like to ensure airtightness. I was However, there is a problem that a gap is generated at an interface of each part in a cooling / heating cycle due to a difference in linear expansion coefficient of each member, and airtightness is reduced.
[0003]
[Patent Document 1]
JP-A-11-304609
[Problems to be solved by the invention]
An object of the present invention is to prevent a decrease in airtightness from terminals and metal leads in a semiconductor pressure sensor having both a pressure change of a medium to be measured and a temperature change of a medium to be measured into an electric signal. It is in.
[0005]
[Means for Solving the Problems]
In a semiconductor pressure sensor that also has a temperature sensor that converts a change in pressure of the medium to be measured and a change in temperature of the medium to be measured into an electric signal, after integrally molding a pipe set with a synthetic resin, the gap between the pipe set and the semiconductor pressure sensor storage case gap is reduced. The airtightness can be ensured by filling and fixing the metal terminal and the epoxy resin having a linear expansion coefficient similar to that of the synthetic resin for airtight sealing of the metal terminal gap.
[0006]
BEST MODE FOR CARRYING OUT THE INVENTION
Hereinafter, a configuration of a semiconductor pressure sensor according to an embodiment of the present invention will be described with reference to FIGS. First, a configuration of a sensor set of a semiconductor pressure sensor according to an embodiment of the present invention will be described with reference to FIGS. FIG. 1 is a sectional view showing a configuration of a semiconductor pressure sensor according to one embodiment of the present invention. FIG. 2 is a plan view of the present invention shown in FIG. FIG. 3 is a rear view of FIG.
[0007]
4 and 5 are sectional views of the pipe set of the present invention. FIG. 6 is a plan view of FIG.
[0008]
First, in the configuration of the pipe set 10 shown in FIGS. 4 and 5, the terminal 11 is inserted and molded with a synthetic resin. The shape is provided with a pressure introducing hole 13, a positioning hole 12 at the time of double molding, and a wall 16 for preventing intrusion of water, gasoline and the like. This intrusion prevention wall has an effect of preventing suction of gasoline or the like due to surface tension by making the root at a right angle. Next, the thermistor 17 for temperature measurement and the terminal 8 for external connection are fixed to the terminal 11 by welding 21. As shown in FIG. 1, in order to configure the exterior case 14, the pipe set 10, the external connection terminals 8 a and 8 b, and the mounting flange forming bush 22 are simultaneously set. The external connection connector 15 and the outer case 14 can be formed by molding.
[0009]
At this time, ventilation holes 19 and 20 for taking in the medium to be measured of the thermistor 18 in FIG. Since the vent holes 19 and 20 have the structure of the present embodiment, it is possible to eliminate the influence of heat applied to the wall temperature of the mounting portion of the outer case 14 and to provide a sensor having good temperature measurement responsiveness.
[0010]
The semiconductor gauge chip 4 is joined to the semiconductor gauge case set 1 on the outer case 14 and the glass base 3 by anodic bonding or the like. This is adhered with a silicone adhesive 2. Next, it is connected to the lead terminal 6 by the aluminum wire 5. Further, as a protection for the semiconductor gauge chip 4, the semiconductor gauge case set 1 covered with the fluorine-based gel 7 is housed, and the external connection terminals 8b, 8c, 8d and the lead terminal 6 are joined by projection welding 21. Thereafter, a capacitor 9a for protecting the semiconductor gauge chip from external electromagnetic noise and the like is connected between GND and Vcc 9b between GND and Vout by soldering. Next, it is important to completely seal the pressure measurement sensor because the airtight leakage affects the characteristics. Therefore, the pipe set 10 and the terminal 11 and the external connection metal terminals 8a, 8b, 8c, Since the resin alone physically shrinks after molding the outer case 14 to form 8d, a minute gap is generated and leakage occurs, and the sealing can be achieved by filling and curing the epoxy resin 17 to seal the gap. . At this time, it is important that the linear expansion coefficients of the outer case resin 14, the metal terminals 8a, 8b, 8c, 8d and the epoxy resin 17 be approximated so that the physical movement is smaller than the adhesive strength of the epoxy resin. In particular, the glass transition temperature of the epoxy resin 17 needs to be higher than the actual use temperature. This is because thermal expansion suddenly increases when the physical property exceeds the glass transition point, and peeling occurs at the bonding interface between the outer case 14 and the epoxy resin 17. Next, the O-ring 24 is mounted to complete the semiconductor pressure / temperature integrated sensor.
[0011]
In each of the above-described examples, the basic concept is included in the contents described in the claims, and individual components among these components are not limited at all.
[0012]
【The invention's effect】
Airtightness from terminals and metal leads can be prevented.
[Brief description of the drawings]
FIG. 1 is a sectional view showing a configuration of a semiconductor pressure sensor according to an embodiment of the present invention.
FIG. 2 is a plan view of the present invention shown in FIG.
FIG. 3 is a rear view of FIG.
FIG. 4 is a sectional view of a pipe set according to the present invention.
FIG. 5 is a sectional view of a pipe set according to the present invention.
FIG. 6 is a plan view of FIG. 5;
[Explanation of symbols]
1 ... Semiconductor gauge case set, 2 ... Silicone adhesive, 3 ... Glass stand, 4 ... Semiconductor gauge chip, 5 ... Aluminum wire, 6 ... Lead terminal, 7 ... Fuso gel.

Claims (6)

A pressure sensor comprising a semiconductor for detecting pressure, comprising a temperature sensor for converting a change in temperature of a medium to be measured into an electric signal, wherein a pipe set is made of a synthetic resin and has a double molded structure. . A pressure sensor, wherein a thermistor for measuring the temperature of the medium to be measured and a metal terminal for external electrical connection are welded and fixed to a metal terminal inserted into the pipe set. A pressure sensor, wherein said double-molded structure is filled with a pipe set, a semiconductor pressure sensor housing case gap, a metal terminal, and an epoxy resin for hermetically sealing the metal terminal gap. The double-molded synthetic resin is made of the same material as the pipe set, has a linear expansion coefficient of 15 to 38 ppm / ° C., a glass transition point of the hermetic sealing epoxy resin is 160 ° C. or higher, and a linear expansion coefficient of 15 to 15. A pressure sensor comprising a combination of 38 ppm / ° C. In the double molding, the structure of the temperature measurement thermistor accommodating portion is provided at a position where a welded portion between the thermistor and the terminal is not visible from a vent of the medium to be measured. A pressure sensor, characterized in that a wall is provided at the thermistor-side end vent of the pipe set.

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