JPH0746066B2 - Semiconductor pressure detector - Google Patents

Description

Description: TECHNICAL FIELD The present invention relates to a semiconductor pressure detecting device, and more particularly to improvement of a liquid sealing structure of a liquid sealing type semiconductor pressure detecting device. INDUSTRIAL APPLICABILITY The present invention is suitable for a semiconductor pressure detecting device for applications requiring high reliability.

[Prior Art] FIG. 5 shows a conventional liquid-sealed semiconductor pressure detecting device.

This device 130 has a pedestal 112 having a silicon diaphragm 116 on one surface and a recess, and a first member 114 having the other surface facing the one surface of the pedestal 112 fixed to the bottom surface 110 of the recess,
A seal diaphragm 140 having an outer peripheral portion that abuts on the first member 114 and forming a closed space 113 that houses the pedestal 112 together with the first member 114; a liquid 107 injected into the closed space 113;
The seal diaphragm 140 has a peripheral edge portion that sandwiches the outer peripheral portion of the seal diaphragm 140 with the first member 114 and a plastically deformable portion.
And a ring-shaped holding member 150 that presses the outer peripheral portion of 140 against the first member 114 to seal the liquid 132 in the closed space 113.

The silicon diaphragm 116 incorporates a semiconductor pressure conversion element (not shown), and the semiconductor pressure conversion element converts the measured pressure transmitted via the seal diaphragm 140 and the liquid 107 into a signal voltage, and converts the signal voltage into a signal voltage. Output is performed via the bonding wire 121 and the lead member 120. The sealing glass material 123 fixes the lead member 120.

The ring-shaped biasing member 150 is plastically deformed and embedded in the linear groove 118 formed in a part 115 of the inner surface of the recess of the first member 114, and holds the pressed state.

The semiconductor pressure detecting device disclosed in Japanese Patent Laid-Open No. 61-11625 has the same structure as that of the semiconductor pressure detecting device shown in FIG. 5, except that the ring-shaped biasing member 150 shown in FIG. By using a biasing member, the C-ring-shaped biasing member is elastically deformed in the radial direction, and is engaged with a ring-shaped groove formed on the inner side surface of the recess of the first member (for example, 115 in FIG. 5). There is.

[Problems Requiring Solution] In the above-described conventional apparatus that plastically deforms and engages the ring-shaped biasing member 150 with the recess inner surface 115 of the first member 114, the metal biasing member 150 is plastically worked. Therefore, it is necessary to prepare a press machine with a dedicated jig. Also, the seal diaphragm
The peripheral main surface of 140 is abruptly pressed when the biasing member 150 is plastically deformed, and therefore excess liquid in the closed space 113 may not be removed.

The above-mentioned other conventional device that engages the C-ring-shaped biasing member with the ring-shaped groove formed on the inner surface of the concave portion of the support base (for example, 115 in FIG. 5) also has a peripheral edge portion of the seal diaphragm when engaged. Since the main surface is rapidly pressed against the first member, it may not be possible to remove the excess liquid in the closed space.

It is an object of the present invention to improve the drawbacks of the conventional liquid-sealed semiconductor pressure detecting device described above, and to provide a liquid-sealed semiconductor pressure detecting device in which an excess liquid does not remain in the sealed space.

[Means for Solving the Problems] The device of the present invention comprises: a first member having a concave portion, the other surface of the pedestal having a silicon diaphragm on one surface, the other surface facing the one surface fixed to the bottom surface of the concave portion; A seal diaphragm having an outer peripheral portion abutting against one member and forming a closed space for accommodating the pedestal with the first member; and a peripheral portion sandwiching the outer peripheral portion of the seal diaphragm with the first member. An urging member having an elastically deformable portion and pressing the outer peripheral portion of the seal diaphragm against the first member to seal the liquid in the closed space; and a main surface of the seal diaphragm opposite to the closed space side. It has a pressure introducing hole for introducing a non-measurement pressure,
It is a semiconductor pressure sensing device which consists of a 2nd member integrally combined with a member.

[Operation] In the liquid-sealed semiconductor pressure detection device of the present invention, the non-measurement pressure is introduced from the pressure introduction hole and acts on the outer main surface of the seal diaphragm. Then, the seal diaphragm is extruded and acts on the liquid in the closed space. The pressurized liquid is
It acts on the entire surface of the silicon diaphragm on the closed space side. The silicon diaphragm forms a reference pressure chamber with the pedestal on the other surface opposite to the one surface, and is bent by the differential pressure between the liquid pressure and the reference pressure chamber pressure. The silicon diaphragm incorporates a semiconductor pressure converting element, and the semiconductor pressure converting element outputs an electric signal corresponding to the deflection to the outside through a lead member.

In the present invention, the peripheral edge of the seal diaphragm is sandwiched between the first member and the elastically deformable biasing member, and the biasing member elastically deforms and biases the peripheral edge of the seal diaphragm against the first member. ing. For this reason, while increasing the urging force of the urging member, the gap between the peripheral portion of the seal diaphragm and the first member that abuts against the peripheral portion gradually becomes narrower, and at the same time, the gap in the sealed space Excess liquid is gradually discharged from the gap. Then, the sealing of the liquid chamber is gradually formed, and finally the sealed space filled with an appropriate amount of liquid is completed.

[Effect] As described above, in the liquid-sealed semiconductor pressure detecting device of the present invention, the peripheral portion of the seal diaphragm is the biasing member and the first member.
It is sandwiched between the member and the first member, and is pressed by the first member with a predetermined pressure by the urging and elastic deformation of the urging member.

Therefore, in the device of the present invention, since the biasing member can be gradually pressed, the excess oil in the closed space is sufficiently discharged and does not remain, the seal diaphragm is deformed or destroyed. . The peripheral main surface of the seal diaphragm is in wide contact with the first member and is further pressed in the direction perpendicular to the main surface, so that the sealing is strong. Furthermore, in the device of the present invention, the biasing member needs to be plastically deformed. Since it is not available, disassembly and adjustment is possible.

[Embodiment] A liquid-sealed semiconductor pressure detecting device of the present invention will be described with reference to an embodiment.

A cross-sectional view of one embodiment of this device is shown in FIG.

This device has a pedestal 5 having a silicon diaphragm 6 on one surface and a recessed portion, and the other surface facing the one surface of the pedestal 5 is abutted on the first member 2 fixed to the bottom surface 14h of the recessed portion and the first member 2. A seal diaphragm 8 that has an outer peripheral portion that is formed and forms a closed space 7 that houses the pedestal 5 with the first member 2, a liquid 7a that is enclosed in the closed space 7, and the outer peripheral portion of the seal diaphragm 8 It has a peripheral portion 9c sandwiched between the member 2 and an elastically deformable portion, and presses the outer peripheral portion of the seal diaphragm 8 against the first member 2 to seal the liquid 7a in the sealed space 7
The first member 2 has a biasing member 9 for sealing and a pressure introducing hole 1d for introducing a measured pressure on the main surface of the seal diaphragm 8 opposite to the closed space 7 side.
And a second member 1 that is integrally coupled with the second member 1.

The first member 2 is iron, and one side 14b side thereof is dug to form circumferential side surfaces 14c, 14e, 14g having different diameters, a circular bottom surface 14h, and ring-shaped step surfaces 14d, 14f.

The silicon diaphragm 6 is fixed to one surface of the pedestal 5 at one main surface, and forms a reference pressure chamber (not shown) sealed together with the pedestal 5. In addition, the silicon diaphragm 6
Has a diaphragm portion that bends due to the pressure difference between the reference pressure chamber and the closed space 7, and a semiconductor pressure conversion element that detects the deflection.

The pedestal 5 is made of glass and is bonded to the recess bottom 14h of the first member 2.

The output terminal 4 is inserted into a through hole 14i penetrating between the two opposite surfaces 14f and 14j of the first member 2 and hermetically sealed by the sealing glass material 3.

The bonding wire 11 connects the exposed end of the output terminal 4 and the output electrode of the semiconductor pressure conversion element (not shown).

The second member 1 is made of metal, has a recessed material having an open surface on one surface 1h side thereof, a female screw side surface 1c and a circular bottom surface 1g, and a first member 2 having a male screw surface 2k in the recessed portion. Are tightened with screws. Further, a guide hole 2a for tightening the screw is provided in one surface 14j of the first member 2, and a pressure introducing hole 1d is formed so as to penetrate through two opposed surfaces 1f and 1b in the central portion of the second member 1. There is. The second member 1 has a circumferential outer surface 1e facing the female screw surface 1c, and a screw surface 1b facing the cylindrical surface of the pressure introducing hole 1d and having a diameter smaller than that of the circumferential outer surface 1e.

The seal diaphragm 8 faces the silicon diaphragm 6, and one main surface of the peripheral portion thereof is a ring-shaped step surface of the first member 2.
It abuts 14d and seals the closed space 7.

The liquid 7a is silicone oil and is enclosed in the closed space 7.

The biasing member 9 is a disc spring member, and has a link-shaped peripheral edge portion 9c, a conical-shaped side surface 9d, and a top disc 9e having a central opening portion 9f, as shown in FIG. Also, the biasing member 9
The circular top 9e is pressed by the circular bottom surface 1g of the second member 1, and the peripheral edge of the seal diaphragm 8 is pressed.

Further, the disc spring member 9 has an opening 9a and a groove 9b for removing excess oil, as shown in FIG.
Communicate with the pressure introducing hole 1d.

Assembly of the semiconductor pressure detecting device will be described below.

First, the sealing diaphragm 8 is arranged on the step surface 14d with one surface 14j of the first member 2 facing downward.

Next, the liquid chamber 7 is vacuum degassed in silicone oil and then returned to atmospheric pressure. Next, the packing 1 is placed in the recess of the second member 1.
0, the disc spring member 9 is set, and the support member 2 is slowly screwed to the second member 1.

According to the above-described embodiment, the first member 2 is screwed to the second member 1, and the disc spring member 9 is pressed by the second member 1 and elastically deforms.
7a leaks into the space 18 at atmospheric pressure through the gap between the seal diaphragm 8 and the step surface 14d, and finally the liquid chamber 7 is completely sealed by screwing. Further, the disc spring member 9 is pressed against the inner surface 14c of the recess of the first member 2 by the above pressing, and the sealing is further strengthened. The excess oil that has leaked out is removed through the space 18 formed by the first member 2 and the second member 1 and the pressure introducing hole 1d communicating with the space 18.

The operation of the semiconductor pressure detecting device will be described below.

The measured pressure is transmitted to the seal diaphragm 8 via the pressure introducing hole 1d and the space 18 communicating with the pressure introducing hole 1d, and the measured pressure is further transmitted to one surface of the silicon diaphragm 6 via the silicone oil 7a. Silicon diaphragm 6
Is deflected by the pressure difference between the measured pressure and the pressure in the reference pressure chamber (not shown), and the deflection changes the resistance of the semiconductor pressure conversion element (not shown) incorporated in the diaphragm. A signal voltage change of a bridge circuit having a semiconductor pressure conversion element is generated, and the signal voltage is
It is electrically transmitted to the outside through the bonding wire 11 and the output terminal pressure 4.

As described above, in the semiconductor pressure detecting apparatus of this embodiment, the sealing diaphragm is simply fixed and excess oil in the liquid chamber is removed simply by screwing the first member 2 to the second member 1 at an appropriate speed. And can be performed at the same time. Moreover, the pressing force can be adjusted by the screw tightening amount, and the screw can be easily disassembled by returning the screw. Further, the disc spring member 9 is pressed and deformed to contact the step surface 14d of the first member 2 as well as the inner surface 14c, so that the sealing is strengthened.

Another embodiment of the disc spring member is shown in FIG. Plate panel member 12
Has a ring-shaped peripheral portion 12a, a conical side surface portion 12d, and a top disk 12e having a central opening 12f, and further an opening portion 12b for adjusting the spring pressure and discharging excess oil.
And a protrusion 12c for preventing rotation.

Another embodiment of the semiconductor pressure detecting device of the present invention is shown in FIG.

This semiconductor pressure detecting device basically has the same structure as the semiconductor pressure detecting device of FIG.

However, in this embodiment, the brim-shaped member 13 is press-fitted into the concave portion of the first member 2 and engages with the inner surface 14c to press and support the peripheral edge portion and the top portion of the disc spring member 9. Further, the collar member 13 has a groove 13a for discharging oil and a hole 13b for transmitting the measured pressure.
With. Therefore, in this embodiment, the sealing of the liquid chamber 7 is completed by press-fitting the collar-shaped member 13 and the second member is not used, so that the first member and the second member can be freely combined or separated.

The collar-shaped member 13 and the inner side surface 14c of the first member 1 may be engaged with each other by a screw surface.

Another effect produced by each of the above-described embodiments is that the contact surface of the entire peripheral edge of the seal diaphragm 8 is pressed against the one surface 14d of the support member with a uniform pressure.

[Brief description of drawings]

FIG. 1 is a sectional view of one embodiment of the semiconductor pressure detecting device of the present invention. 2 and 3 are plan views of one embodiment of the disc spring member. FIG. 4 is a sectional view of another embodiment of the semiconductor pressure detecting device of the present invention. FIG. 5 is a sectional view of a conventional semiconductor pressure detecting device. 2 ... First member, 1 ... Second member 8 ... Seal diaphragm 7a ... Silicon oil (liquid) 9 ... Disc spring member (biasing member)

Claims (4)

[Claims] 1. A first member having a pedestal having a silicon diaphragm on one surface thereof and a concave portion, and the other surface facing the one surface of the pedestal fixed to the bottom surface of the concave portion, and abutting against the first member. A seal diaphragm having an outer peripheral portion and forming a closed space for accommodating the pedestal with the first member, a liquid injected into the closed space, and an outer peripheral portion of the seal diaphragm between the first member. An urging member having a peripheral portion and an elastically deformable portion, which presses the outer peripheral portion of the seal diaphragm against the first member to seal the liquid in the sealed space, and a biasing member on the side opposite to the sealed space side of the seal diaphragm. The main surface has a pressure introducing hole for introducing a non-measurement pressure,
A semiconductor pressure detecting device comprising a second member integrally connected to the member. 2. A disc spring member having a ring-shaped sealing surface that abuts on an outer peripheral portion of a seal diaphragm and an abutting surface that abuts on a second member, and the energizing member can be biased by the second member. A semiconductor pressure detecting device according to claim 1. 3. The biasing member has a disc spring member having a ring-shaped sealing surface that abuts the outer peripheral portion of the seal diaphragm, and a presser foot that abuts and biases the disc spring member to engage the first member. The semiconductor pressure detecting device according to claim 1, wherein the semiconductor pressure detecting device comprises a member. 4. The semiconductor pressure detecting device according to claim 1, wherein the first member and the second member are integrally coupled by screwing.