JPH10185735A - Pressure sensor module - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a pressure sensor module that has less current leakage, has a low material cost, and can be manufactured inexpensively. SOLUTION: A relay substrate 430 made of a ceramic base 431 is joined onto a case 420 of a pressure sensor module 400 where a pressure sensor chip 100 is accommodated inside through the inside and outside of the case 420, and an input/output terminal 440 for transferring to an external signal-processing equipment and the pressure sensor chip 100 are connected on the relay substrate 430. The base 431 is electrically insulated from, for example, the case 420, thus preventing an electrical signal from leaking from the pressure sensor chip 100 to the case 420 and the like.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a pressure sensor module and can be used, for example, for pressure measurement in a high temperature state.

[0002]

2. Description of the Related Art Conventionally, various pressure sensors have been used for measuring a fluid pressure. As a pressure sensor for built-in control, a diaphragm for receiving pressure which can be downsized and a deformation of the diaphragm are detected. Pressure sensor chip provided with a converter for converting the pressure into an electric signal. As such a pressure sensor chip, a strain gauge type pressure sensor chip that converts the deformation of the diaphragm into an electric signal by a strain gauge and a capacitance type pressure sensor chip that detects the deformation of the diaphragm as capacitance are known. I have. FIG. 9 shows a strain gauge type pressure sensor chip capable of accurately measuring a pressure change even in a high temperature atmosphere.
SOI (Silicon OnIns) as shown in
ulrator) type pressure sensor chip. The pressure sensor chip 100 includes a pedestal 10, a silicon diaphragm 20 bonded and fixed on the pedestal 10, a strain gauge 30 formed on the silicon diaphragm 20, and an electrode wiring 40 connected to the strain gauge 30. It is formed including.

The pedestal 10 is a rectangular pillar-shaped solid material having a substantially square planar shape, and a through hole 11 is formed at the center of the substantially square. The silicon diaphragm 20 includes a pressure-sensitive portion 21 that deforms in response to a change in pressure and a leg 22 that surrounds the pressure-sensitive portion 21.
And the leg 22 is joined to the pedestal 10, and the pedestal 1
A measurement chamber 23 is formed by the upper surface of the probe 0, the leg 22, and the pressure-sensitive part 21, and the measurement chamber 23 communicates with the external space through the through hole 11. The strain gauge 30 is formed on the upper surface of the pressure-sensitive portion 21 of the silicon diaphragm 20 with an insulating film 50 interposed therebetween.
Covered by Such a strain gauge 30
As shown in the schematic diagram of FIG. 10, four portions of one silicon diaphragm 20 are formed on the pressure-sensitive portion 21 and are connected to each other by an electrode wiring 40. Then, the four strain gauges 30 are formed by the electrode wires 40.
Is formed. The bridge circuit 70 has a voltage application terminal 71 for applying a voltage and a detection terminal 72 for transmitting an electric signal of the strain gauge 30 to the outside. Each of the voltage application terminal 71 and the detection terminal 72 is connected to a thin metal wire 73 serving as an internal wiring.
Input and output of electrical signals between the device and an external signal processing device.

[0004] Such a pressure sensor chip 100 is housed as shown in FIG.
00. The pressure sensor module 200 includes, in addition to the pressure sensor chip 100, a support 210 that supports and fixes the pressure sensor chip 100, and a case 220 that is joined to the support 210 and covers the pressure sensor chip 100.
And the pressure introducing pipe 23 joined under the support 210
0, an input / output terminal 240 for inputting / outputting an electric signal from / to the pressure sensor chip 100 from outside, and a glass fixing portion 250 for supporting and fixing the input / output terminal 240
And it is formed including.

The support 210 is an integral product made of an Fe—Ni alloy (Kovar, Fernico, etc.), and has a through hole 11 of the pressure sensor chip 100 and the pressure introducing pipe 230 near the center thereof. A hole 211 serving as an introduction passage is formed for communication. A hole 212 that allows the input / output terminal 240 to pass through the inside and outside of the pressure sensor module 200 is formed in another portion of the support 210. Note that the pressure sensor chip 100 is fixed to the support 210 with a glass adhesive 213.

[0006] The case 220 is also a thin bowl-shaped member made of an Fe-Ni-based alloy, and has a hole 221 for venting air substantially in the center of the bottom surface thereof. Are joined. The input / output terminal 240 is a metal rod-shaped member inserted into the hole 212 of the support 210, and is fixed to the support 210 by a glass fixing part (a hermetic seal or the like) 250. 8, a thin metal wire 7 serving as an internal wiring from the pressure sensor chip 100 is provided at the upper end of the input / output terminal 240.
8, and a lead wire, not shown in FIG. 8, is connected to the lower end of the connector 3. The external signal processing device inputs and outputs electric signals to and from the pressure sensor chip 100. Here, the reason why the input / output terminal 240 is supported and fixed to the support 210 via the glass fixing portion 250 is that the support 210 is made of metal,
This is to prevent the current from leaking by insulating it from the current.

The capacitance type pressure sensor chip has electrodes formed on the diaphragm and electrodes arranged opposite to each other, and detects a change in the distance between the electrodes due to the deformation of the diaphragm as a change in capacitance. Although it is different from the strain gauge type pressure sensor chip in principle, the extraction of wiring and the like for detecting an electric signal from the pressure sensor chip is the same as described above.

[0008]

However, in such a conventional pressure sensor module 200, the resistance value of the glass fixing portion 250 decreases as the measurement condition becomes higher, so that the support table 210 and the input / output terminals 240 This causes a problem that the insulation resistance between the pressure sensor chip 100 and the pressure sensor chip 100 decreases, and a current leak occurs. There is also a way to make the support base made of plastic and prevent current leakage.
The plastic support base has a problem that the measurement conditions cannot be set to a very high temperature. Furthermore, it is conceivable that the support base is formed of a material having high heat resistance and good insulation such as ceramics. However, the support and support are inferior in molding and workability as compared with those made of metal or plastic. In addition to the problem that the degree of freedom of the shape of the table is reduced, there is a problem that the material cost and the manufacturing cost of forming the support table are increased.

The present invention has been devised in order to solve the above-mentioned problems, and has as its object to provide a pressure sensor module with less current leakage and low material and manufacturing costs.

[0010]

SUMMARY OF THE INVENTION A pressure sensor module according to the present invention includes a pressure receiving diaphragm and a converter for converting the pressure applied to the diaphragm into an electric signal, and detects the pressure applied to the diaphragm. A support base having a pressure sensor chip for outputting an electric signal and having an introduction passage for guiding a fluid whose pressure is to be detected to the diaphragm and supporting the pressure sensor chip; and a support base joined to the support base and supporting the pressure sensor chip. A pressure sensor module formed including: a case for housing the inside; and an input / output terminal to which a lead wire for transmitting an electric signal from the converter to an external signal processing device is connected. A relay board fixed and provided with the input / output terminals, and the input / output terminals and the converter are connected via the relay board. And a hole is formed in the case so as to pass through the inside and outside of the case. In this hole, any one of the relay board, the input / output terminal, and the internal wiring is in a penetrating state. The hole is provided on one of the side surface of the case and the opposite surface of the case opposite to the support base, and the relay board is electrically insulated from the case and the support base. It is characterized by being.

Here, the transducer provided on the pressure sensor chip is not limited to the above-described SOI type pressure sensor chip using a strain gauge, but may be a diffusion type pressure sensor chip or a capacitance type pressure sensor using the same strain gauge. It also includes a chip, in short, a converter that converts the deformation of the diaphragm into an electric signal is formed on the chip, and all wiring that outputs an electric signal to the outside or inputs an electric signal from the outside is required The target is a pressure sensor chip.
In addition, the holes formed in the case need only be formed at positions where the drawing direction of the input / output terminals is not in the same direction as the introduction passage for guiding the fluid. It may be formed on a side surface portion of a case provided, or may be formed on an upper surface portion of a case which is arranged to face a support base at a predetermined interval.

According to the present invention, the converter on the pressure sensor chip and the input / output terminals can be connected on the relay board having stable electrical insulation regardless of the temperature at the time of pressure measurement. Therefore, leakage of current can be reliably prevented irrespective of the materials of the support base and the case, and an accurate electric signal is transmitted between the pressure sensor chip and an external signal processing device. In addition, since the relay board is formed on the case, the relay board can be oriented in any direction depending on the bonding position between the support base and the case, thereby simplifying the connection between the input / output terminals and the lead wires. Can be

[0013] In the above description, it is preferable to use a relay substrate in which wiring is formed on the surface of a ceramic base material. That is, by using a ceramic base material for the relay board, it is possible to reliably maintain electrical insulation between the case and the input / output terminals even under high temperature measurement conditions. Further, since only the simple relay board of the plate-like body can be made of ceramic and the other parts can be made of inexpensive metal, the production cost of the pressure sensor module can be reduced.

When there are a plurality of input / output terminals on the relay board, the plurality of input / output terminals connected to the outside of the relay board are preferably arranged linearly. That is, since the input / output terminals are connected to the outside of the relay board,
The input / output terminals can be oriented in any direction, and the work of connecting the lead wires to the input / output terminals can be simplified. Further, since the input / output terminals are arranged in a straight line, the connection work between the input / output terminals and the lead wires can be completed simultaneously by a spot welding machine or the like, and the connection work between the lead wires and the input / output terminals can be further improved. Is simplified.

[0015] The relay board is provided with shielding means for preventing a brazing material used for connecting the input / output terminals to the relay board from flowing to the inner end of the relay board. Is preferred. That is, if the shielding means is formed, it is possible to prevent the brazing material from flowing out to the inner end to which the thin metal wire of the relay board is connected, and to reliably connect the relay board and the thin metal wire. It is possible to do. Further, the shielding means may be formed by providing a weir or a step crossing the wiring in the intermediate portion of the relay board, but is preferably a thin layer of ceramics crossing the wiring. That is, if the shielding means is formed of a thin layer of ceramics, it becomes possible to easily form the shielding means on the relay substrate, and since the brazing material is hard to wet the ceramics layer, a portion of the ceramics layer is not required. Thus, the outflow of the brazing material can be shielded as necessary and sufficiently.

[0016]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Embodiments of the present invention will be described with reference to the drawings. The same or similar members or portions as those already described are denoted by the same or similar reference numerals, and description thereof will be omitted or simplified. FIG.
1 shows a cross-sectional view illustrating an internal structure of a pressure sensor using a pressure sensor module according to the present invention. The pressure sensor 300 includes a main body 310 that houses the pressure sensor module 400 therein, and a pressure sensor module 40.
0, which is connected to an upper portion of the pressure sensor module 400 and is connected to an external signal processing device (not shown in FIG. 1) for introducing a fluid to be measured into the pressure sensor module 400. In FIG. 1, the fluid introduction section 320 is provided below the main body 310, and the lead wire storage section 340 is provided above the main body 310.
Are joined and integrated.

The main body 310 has a space formed inside a metal cylinder having both ends opened. The pressure sensor module 400 is housed in this space, and the lower peripheral edge of the opened cylinder is formed. 311 is a fluid introduction unit 3
20 is TIG welded to the upper end. Fluid introduction part 32
0 is the pressure sensor module 40
0 and has an introduction hole 321 leading to zero, and on the outer surface on the tip side,
A male screw portion 322 is formed for connecting a conduit for guiding a fluid to be measured, and a base end side of the introduction hole 321 is connected to a support 410 of a pressure sensor module 400 described later. A part 323 is provided.

The lead wire storage section 340 is closed at the top,
It is made of a metal cylinder having an open lower part, and its lower peripheral edge 341 is joined by laser welding along the upper peripheral edge of the main body 310. Further, a substrate 350 for connecting and fixing the lead wire 330 is provided inside the lead wire storage portion 340, and the upper closed surface 342 is for guiding the lead wire 330 to an external signal processing device. Connection portion 360 is provided.

The connecting portion 360 has a male screw portion 3 on the outer peripheral surface of the cylinder.
61, a concave portion 362 having an inversely tapered shape is formed at the periphery of the opening surface of the distal end toward the inside of the cylinder, and a cable 331 bundled with the lead wires 330 is inserted into the inside of the cylinder. ing. In addition, the male screw portion 36
1 is provided with two cuts along the extending direction of the cylinder, and is expandable in the radial direction. A cover 370 is screw-connected to the male screw portion 361, and inside the cover 370, the lock 371 of the screw portion is secured.
Is provided. The locking stopper 371 has a wedge-shaped distal end 371A in the lower part of FIG. 1, and this distal end is in contact with the concave portion 362, and the proximal end is in contact with the inner surface of the cover 370. And the connection part 3
As the cover 370 is tightened to 60, the locking stopper 371 is lowered downward in FIG. 1, and the radial dimension of the male screw portion 361 is expanded, so that the screwing between the connection portion 360 and the cover portion 370 becomes stronger.

The substrate 350 is provided so as to partition a space in which the lead wire accommodating portion 340 communicates with the main body 310, and is provided in a fixing portion 351 for fixing the lead wire 330 and a pressure sensor module 400 described later. And a hole 352 through which the input / output terminal 440 is inserted. The lead wire 330 and the input / output terminal 440 are connected on the substrate 350.

As shown in FIGS. 2 and 3, the pressure sensor module 400 includes a pressure sensor chip 100, a support 410 for supporting the pressure sensor chip 100, a pressure sensor joined to the support, and an internal pressure sensor. Chip 100
, A relay board 430 provided on the outer surface of the case 420 so as to penetrate inside and outside, an input / output terminal 440 connected to the outside of the relay board 430,
Fine metal wire 7 serving as internal wiring for connecting pressure sensor chip 100 and input / output terminal 440 via relay board 430
3 is formed.

The support table 410 has a shape in which two disks are connected by a cylindrical body, and includes a bottom disk 411 and the bottom disk 4.
11, a cylindrical portion 412 protruding above the cylindrical portion 412,
And a support disk 413 provided thereon and to which the pressure sensor chip 100 is joined. In addition, a passage hole 414 which is an introduction passage penetrating vertically in FIG.
4, a joining protrusion 415 is provided on the periphery of the bottom disk 411 side opening.
Are formed. The support 410 is a member made of an Fe-Ni-based alloy (such as Kovar or Fernico) formed integrally by cutting. Pressure sensor chip 100
Is bonded and fixed on the support table 410 with a glass adhesive 416, and the opening of the passage hole 414 on the support disk 413 side corresponds to the introduction hole 11 of the pressure sensor chip 100. Further, the joining protrusion 415 is connected to the fluid introduction portion 320.
Is joined by electron beam welding. The reason why the electron beam welding is performed is to suppress generation of heat as much as possible and to apply harmful stress to the pressure sensor chip 100 as much as possible.

The case 420 is made of Fe forming the side surface.
A cylindrical body 421 made of a Ni-based alloy, and a ceramic lid 422 which closes the upper part of the cylindrical body 421 and forms an opposing surface of the case 420; 423 are formed. In FIG. 2, a cylindrical body 421 is shown.
Is welded to the periphery of the bottom disk 411 of the support 410, and the upper periphery is formed with a notch formed inside the cylindrical body 421 along the radial cross section. The lid 422 is inserted and fixed in the notch. Although not shown in FIG. 2, the relay board 430 is fixed to the hole 423 by brazing.
The thin metal wires 73 connected to the bridge circuit 70 on the pressure sensor chip 100 are connected to the relay board 430.

The relay board 430 is formed to include a ceramic base material 431 formed by cutting into a substantially rectangular shape, and wiring 432 formed thereon. The wiring 432 is connected to the outer end 4 serving as the long side edge of the base material 431.
30A and the inner end 430B are connected, and a total of five wirings are formed. At the outer end 430A, the above-mentioned input / output terminals 440 are linearly arranged and connected in accordance with the number of five wires, and at the inner end 430B, four metal members from the pressure sensor chip 100 are provided. The thin wire 73 is connected. However, the remaining one is a spare line and is not connected to the pressure sensor chip 100. The voltage application terminal 71 and the detection terminal 72 formed in the bridge circuit 70 on the pressure sensor chip 100 are collected at the left end of the plane of the pressure sensor chip 100 in FIG.
The connection directions of 3 are also aligned in a fixed direction.

On the base material 431, a ceramic thin layer 433 extending in the long side direction is formed on the wiring 432 at the middle part in the short side direction, and a film crossing the five wirings 432 is formed. Such a relay substrate 430 is formed by printing and firing a wiring 432 on a ceramic plate formed in a substantially rectangular shape, and then printing and firing a thin layer 433 made of ceramic, and the input / output terminals 440 are formed by brazing. Each of the wirings 432 is connected. When the input / output terminal 440 is brazed, the brazing material easily wets the wiring 432, and flows out from the outer end 430 </ b> A to the inner end 430 </ b> B along the wiring 432. However, since the thin layer 433 is less likely to be wet, the brazing material does not flow out further to the inner end 430B due to surface tension.

The input / output terminal 440 is connected to the
Medium, stand up vertically from the relay board 430,
The lead wire 3 fixed in the lead wire storage part 340 of FIG.
30. I / O terminal 440 and lead wire 330
Is made by a spot welding machine 500 as shown in FIG. Input / output terminals 440 linearly arranged
And the corresponding lead wire 330 are overlapped, and a plurality of probes 510 are arranged and a plurality of input / output terminals 4 are provided.
The connection between the lead wire 40 and the lead wire 330 is completed only once.

According to this embodiment, the following effects can be obtained. That is, the base material 431 of the relay board 430
Is made of ceramics, so that stable insulation between the case and the input / output terminals can be maintained even in pressure measurement in a high temperature state. Therefore, current leakage does not occur from the support base 410 and the case 420, and the pressure sensor chip 1
00 can be accurately transmitted to an external signal processing device. FIG. 5 shows a comparison of the temperature dependence of the insulation resistance between the pressure sensor module 400 according to the present embodiment and the conventional pressure sensor module 200 described in the conventional example. It can be clearly seen that the change 400A in the insulation resistance of the pressure sensor module 400 is smaller even in a high temperature range (150 ° C. or higher) than the change 200A in the insulation resistance of the pressure sensor module 200.

Since the input / output terminal 440 can be taken out of the case 420 instead of the support table 410, the input / output terminal can be taken out at any position by changing the joining position of the support table 410 and the case 420. Since the costly ceramic portion can be reduced only by the relay board 430, the manufacturing cost of the pressure sensor module 400 can be reduced. I / O terminal 4 on relay board 430
Since the 40s are linearly arranged and connected, the connection between the plurality of input / output terminals 440 and the lead wires 330 can be completed only once by a spot welding machine as shown in FIG. 4, so that the connection work can be reduced. Thus, the manufacturing cost of the pressure sensor can be reduced. The pressure sensor module 400
The case 420 uses a ceramic lid 422, so that even when performing such resistance welding, sparks from the welding machine do not reach the pressure sensor chip 100. It is possible to reduce the occurrence of defects in the process and to prevent dust and the like from adhering to the pressure sensor chip 100 even after the pressure sensor 300 is assembled.

The relay substrate 430 is provided with a thin layer 43 of ceramics.
3 is provided, so that the relay board 4
Even if the input / output terminal 440 is brazed to the outer end 430A of the relay substrate 30, the brazing material is applied to the inner end 43 of the relay board 430.
It does not flow to 0B. Therefore, the fine metal wire 73 will be
Is connected to the relay board 430, no obstacle such as difficulty in connecting the thin metal wires 73 does not occur. The support base 410 of the pressure sensor module 400 is a cylindrical portion 4 having a small diameter at an intermediate portion.
Because of the provision of 12, the stress generated due to the difference in thermal expansion coefficient between the fluid introduction portion 320 and the bottom disk 411 joined via the joining protrusion 415 can be effectively reduced.

The present invention is not limited to the above-described embodiment, but includes the following modifications. That is, in the above-described embodiment, the pressure sensor chip 100 is an SOI type pressure sensor chip using a strain gauge, but is not limited thereto, and may be a diffusion type pressure sensor chip using a strain gauge. A capacitance type pressure sensor chip having a different principle may be used. In short, any pressure sensor chip having a structure that includes a diaphragm that responds to pressure, converts deformation of the diaphragm into an electric signal, and transmits the electric signal to an external signal processing device may be used.

In the above embodiment, the case 420
A hole 423 is formed on the side surface of the case 420, and the relay board 430 is provided so as to penetrate the inside and outside of the case 420. However, the present invention is not limited to this. That is, as shown in FIG. 6, the relay board 430 is provided on the outer side of the opposing surface of the case 620 that is disposed to oppose the support 410 of the case 620, and the holes 62 on the side surfaces of the case 620 are provided.
3, the same effect as described above can be obtained even if the pressure sensor module 600 having the internal wiring 673 penetrating the inside and outside of the case 620 is used. Further, as shown in FIG. 7, a pressure sensor module 700 in which a hole 723 is formed on the facing surface of the case 720 and the internal wiring 773 is provided through the hole 723 may be used. Further, as shown in FIG. 8, a pressure sensor module 800 in which the relay board 430 is provided inside the case 820, and the input / output terminals 440 penetrate inside and outside the case 820 by holes 823 of the case 820 may be used. .

In the above embodiment, the wiring 432
Was formed by printing and firing on the base material 431,
The present invention is not limited to this, and may be a wiring in which a conductive wire is adhered on the base material 431. Further, the input / output terminal 440 may also serve as a connection portion of the thin metal wire 73. In short, any structure may be used as long as the connection between the thin metal wire 73 and the input / output terminal 440 can be performed on the base material 431.

Further, in the above embodiment, the base material 431 is used.
Was made of ceramic, but is not limited to this.
Other materials may be used as the base material as long as the material can secure electrical insulation with 10 or the like. The base material 431 has a substantially rectangular shape, but is not limited to this. If it does not interfere with the connection between the input terminal 440 and the lead wire 330 by the spot welding machine 500, the outer end of the relay board 430 may be used. And the shape of the inner end may be other shapes. Other specific structures, shapes, and the like at the time of carrying out the present invention may be other structures and the like as long as the object of the present invention can be achieved.

[0034]

According to the pressure sensor module of the present invention as described above, since the relay board can reliably insulate from the support base or the like, the current leakage can be reduced and such a pressure leak can be reduced. The pressure sensor module can be manufactured at low cost.

[Brief description of the drawings]

FIG. 1 is a cross-sectional view illustrating an internal structure of a pressure sensor according to an embodiment of the present invention.

FIG. 2 is a cross-sectional view illustrating a structure of a pressure sensor module according to the embodiment.

FIG. 3 is a plan view of the pressure sensor module according to the embodiment.

FIG. 4 is a cross-sectional view illustrating a method for connecting an input / output terminal and a lead wire of the pressure sensor according to the embodiment described above.

FIG. 5 is a diagram comparing the temperature dependence of a change in insulation resistance between the embodiment described above and the conventional example.

FIG. 6 is a cross-sectional view illustrating a structure of a pressure sensor module according to a modification of the present invention.

FIG. 7 is a sectional view illustrating a structure of a pressure sensor module according to another modification of the present invention.

FIG. 8 is a cross-sectional view illustrating a structure of a pressure sensor module according to still another modification of the present invention.

FIG. 9 is a cross-sectional view illustrating an internal structure of an SOI type pressure sensor chip using a strain gauge.

FIG. 10 is a schematic plan view illustrating an electrode wiring structure of the above-described pressure sensor chip.

FIG. 11 is a cross-sectional view illustrating a structure of a conventional pressure sensor module.

[Explanation of symbols]

Reference Signs List 20 diaphragm 30 converter 73, 673, 773 internal wiring 100 pressure sensor chip 330 lead 400, 600, 700, 800 pressure sensor module 410 support base 414 introduction passage 420, 620, 720, 820 case 423, 623, 723, 823 Hole 430 Relay board 431 Base 432 Wiring 433 Shielding means (ceramic thin layer) 440 Input / output terminal

Claims (5)

[Claims] 1. A pressure receiving diaphragm comprising: a pressure receiving diaphragm; and a converter for converting a pressure applied to the diaphragm into an electric signal. The pressure sensor chip outputs an electric signal of the pressure applied to the diaphragm. A support for supporting the pressure sensor chip formed with an introduction passage for guiding a fluid to be detected to the diaphragm; a case joined to the support and accommodating the pressure sensor chip therein; An input / output terminal to which a lead wire for transmitting a signal to an external signal processing device is connected, the relay board being fixed to the case and provided with the input / output terminal. And an internal wiring for connecting the input / output terminal and the converter via the relay board. A hole penetrating inside and outside is formed, and in this hole, the relay board, the input / output terminal,
One of the internal wirings is disposed in a penetrating state, and the hole is provided on one of a side surface of the case and a facing surface of the case opposite to the support table, and the relay board is provided with the case and the case. A pressure sensor module, wherein the pressure sensor module is electrically insulated from the support base. 2. The pressure sensor module according to claim 1, wherein the relay substrate is formed by forming wiring on a surface of a ceramic base material. 3. The pressure sensor module according to claim 1, wherein a plurality of wirings are formed on the relay board, and the plurality of input / output terminals are connected to the outside of the relay board. Is a pressure sensor module which is arranged in a straight line. 4. The pressure sensor module according to claim 1, wherein a brazing material used for connecting the input / output terminals to the relay board is provided on the relay board. A pressure sensor module, wherein a shielding means for preventing the liquid from flowing out to an inner end of the pressure sensor module is formed. 5. The pressure sensor module according to claim 4, wherein said shielding means is formed of a thin layer of ceramics traversing wiring on said relay board.