阅读说明：本技术 压力传感器 (Pressure sensor ) 是由 泷本和哉 柴田浩 于 2017-12-28 设计创作，主要内容包括：在压力传感器中,粘接剂层(50)形成于凹部(18R)内,凹部(18R)形成于芯片安装部件(18)的与传感器芯片(16)的被粘接面对置的一端部,并且粘接剂层(50)形成于密封玻璃(14)的相邻于芯片安装部件(18)的一端部的端面与传感器芯片(16)的面向该端面的外周缘之间的部分。(in the pressure sensor, an adhesive layer (50) is formed in a recess (18R), the recess (18R) is formed in one end portion of a chip mounting member (18) that faces an adhered surface of a sensor chip (16), and the adhesive layer (50) is formed in a portion between an end surface of a seal glass (14) adjacent to the one end portion of the chip mounting member (18) and an outer peripheral edge of the sensor chip (16) that faces the end surface.)

1. A pressure sensor is characterized by comprising:

A sensor unit including a sensor chip that detects pressure and sends out a detection output signal, and a support member that supports the sensor chip via an adhesive layer; and

A sensor unit housing section for housing the sensor unit,

The support member has a recess for measuring a predetermined coating amount of the adhesive so as to form the adhesive layer having a predetermined film thickness.

2. The pressure sensor of claim 1,

In the case where the supporting member is a chip-mounted member, the recess is a depression formed at one end of the chip-mounted member facing the surface of the sensor chip.

3. The pressure sensor of claim 1,

In the case where the supporting member is a chip-mounted member, the recess is a gap formed between one end of the chip-mounted member and the surface of the sensor chip.

4. The pressure sensor of claim 1,

In the case where the support member is a sealing glass, the recess is a depression formed in an end portion of the sealing glass facing the surface of the sensor chip.

5. The pressure sensor of claim 1,

In the case where the support member is a base, the recess is a depression formed in an end surface of the base facing the surface of the sensor chip.

6. The pressure sensor according to any one of claims 1 to 5,

The adhesive is applied to the recess so as to be more than the inner volume of the recess so that the adhesive overflows from the recess.

7. The pressure sensor according to any one of claims 1 to 5,

The diameter of the inner circumferential surface forming the recess is set smaller than the length of a diagonal line of the sensor chip.

8. The pressure sensor according to any one of claims 1 to 5,

The diameter of the inner circumferential surface forming the recess is set larger than the length of the diagonal line of the sensor chip.

9. A pressure sensor is characterized by comprising:

A sensor unit including a sensor chip that detects pressure and sends out a detection output signal, and a support member that supports the sensor chip via an adhesive layer; and

A sensor unit housing section for housing the sensor unit,

The support member has a recess of a predetermined depth to which an adhesive is to be applied so as to form the adhesive layer having a predetermined film thickness,

the recessed portion has a cavity in which the adhesive is not applied in a local area around the adhesive applied to a substantially central portion of the recessed portion at a depth of the recessed portion or more.

Technical Field

The present invention relates to a pressure sensor.

Background

The sensor cell constitutes a part of a liquid-sealed semiconductor pressure sensor, and is disposed in a liquid-sealed chamber (pressure receiving space) formed between a base and a diaphragm, as shown in patent document 1, for example. Such a sensor unit is configured to include, for example, the following components as main components: a diaphragm sandwiched between the base and the receiving member; a pressure receiving space as a liquid seal chamber formed above the diaphragm and storing oil as a pressure transmission medium; a sensor chip that is disposed in the pressure receiving space and detects pressure fluctuations of the oil via a diaphragm (referred to as a semiconductor pressure detection element in patent document 1); a base body that supports the sensor chip; and a plurality of terminal pins that send out an output signal from the sensor chip and supply power to the sensor chip.

For example, as shown in patent document 2, such a sensor chip is bonded to a bottom wall portion that forms a bottom portion of a recess formed in a package member via an adhesive layer made of a silicon-based adhesive. The adhesive layer has a predetermined Young's modulus, and the thickness of the adhesive layer is set to a predetermined thickness of 110 μm or more. The reason why the thickness of the adhesive layer is set as described above is that: as the thickness of the adhesive layer is larger, the force applied from the package member to the sensor element is more easily relaxed by the adhesive layer, and the variation in sensor characteristics due to the temperature change can be suppressed as much as possible.

As shown in patent document 3, for example, the following technique is proposed: in order to suppress a change in the characteristics of the sensor element due to the deformation caused by the thermal stress generated by the deformation of the resin case, a recess for applying an adhesive is provided in the bottom of a recessed portion in the bottom surface of the resin case for disposing the base of the sensor element. The recess has a depth of about 0.05mm to 0.2 mm. This prevents the bottom surface of the corner of the sensor element from approaching to a state of contact with the resin case, and reduces the influence of deformation of the resin case on the characteristics of the sensor element. As a result, stress from the outside and stress due to deformation of the resin case are relaxed, and changes in the characteristics of the sensor element are reduced.

Disclosure of Invention

in the manufacturing process of the pressure sensor disclosed in patent documents 2 and 3, a small amount of adhesive is applied to the surface to be bonded of the sealing member or the resin case for bonding the sensor element, and an adhesive layer having a predetermined film thickness is uniformly formed.

However, there is a limit to measuring the amount of adhesive applied and managing the film thickness with high accuracy, and the film thickness may not be uniform.

In view of the above problems, an object of the present invention is to provide a method for manufacturing a pressure sensor capable of obtaining an adhesive layer having a uniform thickness without performing high-precision control of the amount of adhesive applied.

In order to achieve the above object, a pressure sensor according to the present invention includes: a sensor unit including a sensor chip that detects pressure and sends out a detection output signal, and a support member that supports the sensor chip via an adhesive layer; and a sensor unit housing section that houses the sensor unit, the support member having a recess for measuring a predetermined coating amount of the adhesive so as to form an adhesive layer having a predetermined film thickness.

Further, it is preferable that the recess is a depression formed at one end of the chip mounting member facing the surface of the sensor chip when the supporting member is the chip mounting member, and it is preferable that the recess is a gap formed between the one end of the chip mounting member and the surface of the sensor chip when the supporting member is the chip mounting member.

further, it is preferable that the concave portion is a depression formed in an end portion of the sealing glass facing the surface of the sensor chip when the supporting member is the sealing glass, and that the concave portion is a depression formed in an end surface of the base facing the surface of the sensor chip when the supporting member is the base.

The adhesive is preferably applied to the inner volume of the recess or more so that the adhesive overflows from the recess.

Preferably, the diameter of the inner circumferential surface forming the recess is set smaller than the length of the diagonal line of the sensor chip, or the diameter of the inner circumferential surface forming the recess is set larger than the length of the diagonal line of the sensor chip.

Further, a pressure sensor according to the present invention includes: a sensor unit including a sensor chip that detects pressure and sends out a detection output signal, and a support member that supports the sensor chip via an adhesive layer; and a sensor unit housing section for housing the sensor unit, wherein the support member has a recess of a predetermined depth to which the adhesive is to be applied so as to form an adhesive layer having a predetermined film thickness, and the recess has a cavity, to which the adhesive is not applied, locally around the adhesive applied to a substantially central portion of the recess at a depth equal to or greater than the depth of the recess.

According to the pressure sensor of the present invention, the supporting member has the recess for measuring the predetermined coating amount of the adhesive to form the adhesive layer of the predetermined film thickness, so that the adhesive layer of the same film thickness can be obtained without performing high-precision management of the coating amount of the adhesive.

drawings

Fig. 1 is a partial sectional view showing a main part of a sensor unit in one example of the pressure sensor of the present invention.

Fig. 2 is a sectional view showing the structure of an example of the pressure sensor of the present invention.

Fig. 3A is a partial cross-sectional view showing a main part of a modified example of the sensor unit in the pressure sensor of the present invention.

Fig. 3B is a partial cross-sectional view showing a main part of a modified example of the sensor unit in the pressure sensor of the present invention.

Fig. 4A is a partial cross-sectional view showing a main part of a modified example of the sensor unit in the pressure sensor of the present invention.

Fig. 4B is a partial cross-sectional view showing a main part of a modified example of the sensor unit in the pressure sensor of the present invention.

Fig. 4C is a partial cross-sectional view showing a main part of a modified example of the sensor unit in the pressure sensor of the present invention.

fig. 5A is a partial sectional view showing a main portion of a sensor unit used in another example of the pressure sensor of the present invention.

Fig. 5B is a partial sectional view showing a main portion of a sensor unit used in another example of the pressure sensor of the present invention.

fig. 6A is a partial cross-sectional view showing a main part of a modified example of a sensor unit used in another example of the pressure sensor of the present invention.

Fig. 6B is a partial sectional view showing a main part of a modified example of the sensor unit used in another example of the pressure sensor of the present invention.

Detailed Description

Fig. 2 schematically shows the structure of an example of the pressure sensor of the present invention.

In fig. 2, the pressure sensor includes a joint member 30 and a sensor unit housing portion, wherein the joint member 30 is connected to a pipe for guiding a fluid in order to detect a pressure, the sensor unit housing portion is connected to the base plate member 28 of the joint member 30, houses a sensor unit described later, and supplies a detection output signal from the sensor chip to a predetermined pressure measuring device.

A female screw portion 30fs to be screwed into the male screw portion of the connection portion of the pipe is provided inside the metal joint member 30. The female screw portion 30fs communicates with a port 30a of the joint member 30 that guides the fluid supplied from the direction indicated by the arrow P to the pressure chamber 28A described later. One open end of the port 30a opens to a pressure chamber 28A formed between the base plate 28 of the joint member 30 and the diaphragm 32 of the sensor unit.

The outer contour of the sensor unit housing is formed by a cylindrical waterproof case 20 as a cover member. An opening 20b is formed at the lower end of the waterproof resin case 20. The peripheral edge of the base plate member 28 of the joint member 30 is engaged with a step portion of the peripheral edge of the opening 20b which is the inner side.

Air or liquid as a fluid is supplied into the pressure chamber 28A through the port 30a of the joint member 30. The lower end surface of the housing 12 of the sensor unit is placed on the base plate 28.

The sensor unit detects the pressure in the pressure chamber 28A and sends out a detection output signal, and the sensor unit includes as main elements: a cylindrical case 12; a metal diaphragm 32 that isolates the pressure chamber 28A from the inner peripheral portion of the housing 12; a sensor chip 16 having a plurality of pressure detection elements; a metal chip mounting member 18 that supports the sensor chip 16 at one end portion thereof via an adhesive layer 50; an input/output terminal group 40ai (i is 1 to 8) electrically connected to the sensor chip 16; and a sealing glass 14 that fixes the input/output terminal group 40ai and the oil filling pipe 44 between the outer peripheral surface of the chip mounting component 18 and the inner peripheral surface of the case 12.

The diaphragm 32 is supported by one lower end surface of the casing 12 facing the pressure chamber 28A. The diaphragm protection cover 34 has a plurality of communication holes 34a, and the diaphragm protection cover 34 protects the diaphragm 32 disposed in the pressure chamber 28A. The peripheral edge of the diaphragm protection cover 34 is joined together with the peripheral edge of the diaphragm 32 to the lower end face of the housing 12 made of stainless steel by welding.

A liquid sealed chamber is formed between the metal diaphragm 32 and the end faces of the sensor chip 16 and the seal glass 14 facing each other, and a predetermined amount of silicone oil PM or a fluorine-based inert liquid is filled in the liquid sealed chamber as a pressure transmission medium through, for example, an oil filling pipe 44. After the oil is filled, one end of the oil filling pipe 44 is crushed and closed as indicated by a two-dot chain line.

The silicone oil is, for example, a silicone oil having a dimethylpolysiloxane structure composed of siloxane bonds and organic methyl groups. The fluorine-based inert liquid may be, for example, a liquid having a perfluorocarbon structure, a liquid having a hydrofluoroether structure, or an oligomer of chlorotrifluoroethylene, or may be a compound having a structure in which fluorine and chlorine are bonded to a main chain and both ends have fluorine and chlorine.

A metal potential adjustment member 17 is further provided between the sensor chip 16 and the diaphragm 32 disposed in a recess formed in an end portion of the sealing glass 14, and the metal potential adjustment member 17 is supported on a lower end surface of the sealing glass 14. The potential adjustment member 17 is connected to a terminal having a communication hole and connected to the zero potential of the circuit of the sensor chip 16, as shown in japanese patent No. 3987386, for example.

The input/output terminal group 40ai (i ═ 1 to 8) includes two power supply terminals, one output terminal, and five adjustment terminals. Both end portions of each terminal protrude toward a recess formed in an end portion of the sealing glass 14 and a hole of a terminal block 24 described later. Two power supply terminals and one output terminal are connected to the core wire 38a of each lead 38 via the connection terminal 36. Each lead 38 is connected to a predetermined pressure measuring device. In addition, only four terminals among the eight terminals are shown in fig. 2. The input/output terminal group 40ai and the sensor chip 16 described later are connected by bonding wires Wi.

The sensor chip 16 has a plurality of pressure detection elements, and is configured to include, for example: a main body portion formed of silicon and having a substantially rectangular shape; a circuit layer formed on the upper end surface of the main body and forming a processing circuit; an insulating film layer as a second layer laminated on an upper surface of the circuit layer as the first layer; a shielding layer made of aluminum formed on the insulating film layer; and a protective layer that protects an upper layer portion of the shield layer. The length of the diagonal line of the rectangular sensor chip 16 is set to be slightly larger than the diameter of the chip-mounted component 18, for example.

The sensor chip 16 is bonded to one end of the chip-mounted component 18 via an adhesive layer 50.

As partially enlarged in fig. 1, the adhesive layer 50 is formed in the recess 18R, wherein the recess 18R is formed in one end portion of the chip mounting member 18 facing the surface to be bonded of the sensor chip 16, and the adhesive layer 50 is formed in a portion between an end surface of the seal glass 14 adjacent to the one end portion of the chip mounting member 18 and an outer peripheral edge of the sensor chip 16 facing the end surface. A portion between an end face of the sealing glass 14 adjacent to one end portion of the chip mounting component 18 and an outer peripheral edge of the sensor chip 16 facing the end face is formed of, for example, an excess adhesive agent that overflows from inside a recess 18R, where the recess 18R serves as a measuring recess for measuring a predetermined application amount of the adhesive agent. One end of the recess 18R opens toward the surface to be bonded of the sensor chip 16. The recess 18R as a measurement recess for measuring a predetermined amount of adhesive applied has a depth Dp such that the thickness of the adhesive layer is 5 μm or more, for example. The material of the adhesive layer 50 is, for example, a silicone adhesive described in the specification of a patent application filed earlier by the present applicant (application No.: Japanese patent application No. 2016-185678). The material of the chip-mounted component 18 is, for example, a metal such as an iron-nickel alloy or stainless steel.

By setting the amount of adhesive applied to the recess 18R to be equal to or greater than the internal volume of the recess 18R, such as by flowing out of the recess 18R, the adhesive layer 50 having a uniform thickness is formed, and it is not necessary to accurately control the amount of adhesive applied.

The terminal block 24 on which the input-output terminal group 40ai is arranged is molded from a resin material such as polybutylene terephthalate (PBT). The terminal block 24 has a plurality of holes into which the input/output terminal group 40ai is inserted, and has a cavity portion with a predetermined volume inside. The lower end surface of the terminal block 24 is bonded to the upper end surface of the case 12 with a silicone adhesive so as to cover the upper end surface of the sealing glass 14. Thereby, the annular adhesive layer 10a having a predetermined thickness is formed on the upper end surface of the case 12. A coating layer 10b made of a silicone adhesive is formed with a predetermined thickness on the entire upper end surface of the sealing glass 14 from which the input/output terminal group 40ai protrudes.

An annular protrusion 24P protruding toward the sealing glass 14 is formed on the inner peripheral surface of the cavity forming the terminal block 24 and on the inner peripheral surface facing the upper end surface of the sealing glass 14. The protruding length of the annular protrusion 24P is set according to the viscosity of the covering layer 10 b. By forming the annular projecting portion 24P in this way, a part of the coating layer 10b after coating is pulled by surface tension into a narrow space between the annular projecting portion 24P and a portion of the inner peripheral surface forming the cavity of the terminal block 24, which is substantially orthogonal to the upper end surface of the sealing glass 14, and is held, so that the coating layer 10b is not applied to be deviated to one side in the cavity of the terminal block 24. The covering layer 10b is formed to have a predetermined thickness on the upper end surface of the sealing glass 14, but may be formed to cover a part of the plurality of terminal pins 40ai protruding from the upper end surface of the sealing glass 14 as shown in the portion 10 c. As a result, the silicone adhesive layer 10 including the coating layer 10a, the coating layer 10b, and the coating layer 10c is formed as an electrostatic protection layer on the upper end surface of the case 12 and the entire upper end surface of the sealing glass 14. Therefore, by forming the electrostatic protection layer with the silicone adhesive in this manner, the electrostatic withstand voltage of the sensor cell can be improved without being affected by the presence or absence of the ESD protection circuit.

The silicone adhesive is preferably an addition type one-component adhesive having flexibility, for example. The silicone adhesive is, for example, an adhesive having a low molecular siloxane bond. Further, since the silicone adhesive has good compatibility with silicone oil, there is no fear that the adhesiveness of the silicone adhesive deteriorates even if silicone oil or the like is mixed in the silicone adhesive.

A sealing material 26 is filled in a predetermined amount between the outer peripheral surface of the terminal block 24 and the outer peripheral surface of the end cap 22 coupled to the terminal block 24 and covering the hole and the inner peripheral surface of the waterproof case 20, and between the inner peripheral surface of the waterproof case 20 and the outer peripheral surface of the case 12. The terminal block 24 and the end cap 22 are disposed in the waterproof case 20 so as to face the base plate 28 of the joint member 30 through the sensor unit.

The upper end face of the end cap 22 protrudes upward from the open end of the waterproof case 20. That is, the position of the upper end surface of the end cap 22 is higher than the position of the opening end surface of the waterproof case 20.

In the example shown in fig. 1, the adhesive layer 50 is formed in the recess 18R formed at one end portion of the chip mounting member 18, but the present invention is not limited to this example, and, for example, as shown partially enlarged in fig. 3A, a recess 18 ' R having a predetermined depth Dp may be formed in a gap between an end surface of the chip mounting member 18 ' facing the surface to be bonded of the sensor chip 16 and the surface to be bonded of the sensor chip 16 by using a chip mounting member 18 ' having a length slightly shorter than the length of the chip mounting member 18 along the central axis. In the example shown in fig. 3A, and fig. 3B, 4A, 4B, and 4C described later, the same components as those in the example shown in fig. 1 are denoted by the same reference numerals, and redundant description thereof is omitted.

The adhesive layer 50 is formed in the recess 18' R and at a portion where the end face of the adjacent seal glass 14 intersects with the outer peripheral edge of the sensor chip 16 facing the end face.

The portion of the end surface of the sealing glass 14 adjacent to the sensor chip 16, which intersects the outer peripheral edge of the sensor chip 16 facing the end surface, is formed of, for example, excess adhesive that overflows from inside the recess 18' R. The recess 18' R has a depth Dp such that the thickness of the adhesive layer is 5 μm or more, for example.

By setting the amount of adhesive applied to the recess 18 ' R to be equal to or greater than the internal volume of the recess 18 ' R, such as by flowing out of the recess 18 ' R, the adhesive layer 50 having the same thickness is formed, and thus it is not necessary to precisely control the amount of adhesive applied.

in the above example, the sensor chip 16 of the sensor unit is supported by one end portion of the chip mounting member 18 held in the sealing glass 14, but the present invention is not limited to this example, and for example, the sensor chip 16 may be directly fixed to a portion of the sealing glass 14' facing the bonded surface of the sensor chip 16 as shown in fig. 3B without using the chip mounting member 18. A concave portion 14 'Ga for forming the adhesive layer 50 is formed in a portion of the sealing glass 14' facing the surface to be bonded of the sensor chip 16. For example, when the sealing glass 14 'is formed, the concave portion 14' Ga is formed by a carbon jig. The recess 14' Ga has a predetermined depth Dp such that the thickness of the adhesive layer 50 is 5 μm or more, for example. The adhesive layer 50 is formed in the recess 14' Ga and at a portion where an end surface of the sealing glass 14 adjacent to the sensor chip 16 intersects with an outer peripheral edge of the sensor chip 16 facing the end surface. The portion of the sealing glass 14 where the end surface adjacent to the sensor chip 16 intersects the outer peripheral edge of the sensor chip 16 facing the end surface is formed of, for example, excess adhesive that overflows from inside the recess 14' Ga.

As partially enlarged in fig. 4A, the diameter of the chip-mounted component 48 may be set larger than the length of a diagonal line of the quadrangle of the sensor chip 16 (hereinafter also referred to as the length of the diagonal line). In this case, the sensor chip 16 is bonded to one end of the chip mounting member 18 via the adhesive layer 50.

The adhesive layer 50 is formed in the recess 48R, wherein the recess 48R is formed in one end portion of the chip mounting member 48 facing the surface to be bonded of the sensor chip 16, and the adhesive layer 50 is formed in a portion where an end surface of the one end portion of the chip mounting member 48 is extended and intersects with the outer peripheral edge of the sensor chip 16 facing the end surface. The portion where the extended end surface of the chip mounting member 48 and the outer peripheral edge of the sensor chip 16 facing the end surface intersect is formed by, for example, excess adhesive that has overflowed from the inside of the recess 48R by surface tension. The recess 48R has a depth Dp such that the thickness of the adhesive layer is 5 μm or more, for example. The material of the chip-mounted component 48 is the same as that of the chip-mounted component 18 described above, and is, for example, a metal such as an iron-nickel alloy or stainless steel.

By setting the amount of adhesive applied to the recess 48R to be equal to or greater than the internal volume of the recess 48R, such as by flowing out of the recess 48R, the adhesive layer 50 having a uniform film thickness is formed, and it is not necessary to accurately control the amount of adhesive applied.

As partially enlarged in fig. 4B, a recess 48 ' R having a predetermined depth Dp may be formed between the end surface of the chip mounting member 48 ' facing the surface to be bonded of the sensor chip 16 and the surface to be bonded of the sensor chip 16 by using a chip mounting member 48 ' having a length slightly shorter than the length of the chip mounting member 48 along the central axis.

The adhesive layer 50 is formed in the recess 48' R and at a portion where the extended surface of the end surface of the sealing glass 14 adjacent to the sensor chip 16 intersects with the outer peripheral edge of the sensor chip 16 facing the end surface.

The portion where the extended surface of the end surface of the sealing glass 14 adjacent to the sensor chip 16 intersects the outer peripheral edge of the sensor chip 16 facing the end surface is formed of, for example, excess adhesive that overflows from the inside of the recess 48' R. The recess 48' R has a depth Dp such that the thickness of the adhesive layer is 5 μm or more, for example.

By setting the amount of adhesive applied to the recess 48 ' R to be equal to or greater than the internal volume of the recess 48 ' R, such as by flowing out of the recess 48 ' R, the adhesive layer 50 having a uniform film thickness is formed, and it is not necessary to precisely control the amount of adhesive applied.

In the above example, the sensor chip 16 of the sensor unit is supported by one end portion of the chip mounting member 48 held in the sealing glass 14, but the present invention is not limited to this example, and the sensor chip 16 may be directly fixed to a portion of the sealing glass 14' facing the bonded surface of the sensor chip 16 as shown in fig. 4C without using the chip mounting member 48. A recess 14 'Gb for forming the adhesive layer 50 is formed in a portion of the sealing glass 14' facing the surface to be bonded of the sensor chip 16. As partially enlarged in fig. 4C, the diameter of the inner peripheral surface forming the recess 14' Gb may be set larger than the length of the diagonal line of the sensor chip 16. For example, when the sealing glass 14 'is molded, the recess 14' Gb is formed by a carbon jig. The recess 14' Gb has a predetermined depth Dp where the thickness of the adhesive layer 50 is 5 μm or more, for example. The adhesive layer 50 is formed in the recess 14 'Gb and at a portion where an end surface of the seal glass 14' adjacent to the sensor chip 16 intersects with an outer peripheral edge of the sensor chip 16 facing the end surface. The portion where the end surface of the sealing glass 14 'adjacent to the sensor chip 16 intersects the outer peripheral edge of the sensor chip 16 facing the end surface is formed of, for example, excess adhesive that overflows from inside the recess 14' Gb.

Fig. 5A shows a main part of a sensor unit in another example of the pressure sensor of the present invention in a partially enlarged manner.

In fig. 5A, as shown in patent document 1, for example, the sensor unit includes, as main components: a diaphragm (not shown) sandwiched between the base 54 and a receiving member (not shown); a pressure receiving space (not shown) as a liquid seal chamber formed above the diaphragm and storing oil as a pressure transmission medium; a sensor chip 16 disposed in the pressure receiving space and detecting pressure fluctuations of the oil via a diaphragm; a metal base 54 for supporting the sensor chip 16; and a plurality of terminal pins 40' ai that send output signals from the sensor chip 16 and supply power to the sensor chip 16.

In the example shown in fig. 5A, and fig. 5B, 6A, and 6B described later, the same components as those in the example shown in fig. 1 are denoted by the same reference numerals, and redundant description thereof is omitted.

The sensor chip 16 is directly fixed to the surface of the base 54 facing the surface to be bonded of the sensor chip 16. A recess 54Ga for forming the adhesive layer 50 is formed in a portion of the base 54 facing the surface to be bonded of the sensor chip 16. One end of the recess 54Ga opens toward the bonded surface of the sensor chip 16. The recess 54Ga has a predetermined depth Dp such that the thickness of the adhesive layer 50 is 5 μm or more, for example. The diameter of the inner peripheral surface of the base 54 on which the concave portion 54Ga is formed is set to be slightly smaller than the length of the diagonal line of the sensor chip 16.

The adhesive layer 50 is formed in the recess 54Ga and in a portion of the base 54 where an end surface adjacent to the sensor chip 16 intersects with an outer peripheral edge of the sensor chip 16 facing the end surface. The portion of the base 54 where the end surface adjacent to the sensor chip 16 intersects the outer peripheral edge of the sensor chip 16 facing the end surface is formed of, for example, excess adhesive that overflows from the inside of the recess 54 Ga. By setting the coating amount of the adhesive to be equal to or larger than the internal volume of the recess 54Ga as it overflows from the recess 54Ga in this way, the adhesive layer 50 having a uniform film thickness is formed, and it is not necessary to control the coating amount of the adhesive with high accuracy.

The terminal pins 40' ai are supported by the through holes of the base 54 via the sealing glass 56. The terminal pins 40' ai are connected to the sensor chip 16 by bonding wires Wi.

In the example shown in fig. 5A, the base 54 is formed of a metal material, but the present invention is not limited to this example, and for example, as shown in fig. 5B, the base 54' may be formed of a resin material.

The sensor chip 16 is directly fixed to the surface of the base 54' facing the surface to be bonded of the sensor chip 16. A recess 54 'Gb for forming the adhesive layer 50 is formed in a portion of the base 54' facing the surface to be bonded of the sensor chip 16. One end of the recess 54' Gb opens toward the bonded surface of the sensor chip 16. The recess 54' Gb has a predetermined depth Dp such that the thickness of the adhesive layer 50 is 5 μm or more, for example. The diameter of the inner peripheral surface of the base 54 'where the recess 54' Gb is formed is set to be slightly smaller than the length of the diagonal line of the sensor chip 16.

the adhesive layer 50 is formed in the recess 54 'Gb and at a portion of the base 54' where an end surface adjacent to the sensor chip 16 intersects with an outer peripheral edge of the sensor chip 16 facing the end surface. The portion of the base 54 'where the end surface adjacent to the sensor chip 16 intersects the outer peripheral edge of the sensor chip 16 facing the end surface is formed of, for example, excess adhesive that overflows from inside the recess 54' Gb. By setting the amount of adhesive applied to the recess 54 ' Gb to be equal to or greater than the internal volume of the recess 54 ' Gb as if the adhesive were to overflow from the recess 54 ' Gb, the adhesive layer 50 having a uniform thickness is formed, and it is not necessary to accurately control the amount of adhesive applied.

Fig. 6A shows a main part of a sensor unit in another example of the pressure sensor of the present invention in a partially enlarged manner.

in fig. 6A, as shown in patent document 1, for example, the sensor unit includes, as main components: a diaphragm (not shown) sandwiched between the base 64 and a receiving member (not shown); a pressure receiving space (not shown) as a liquid seal chamber formed above the diaphragm and storing oil as a pressure transmission medium; a sensor chip 16 disposed in the pressure receiving space and detecting pressure fluctuations of the oil via a diaphragm; a metal base 64 for supporting the sensor chip 16; a plurality of terminal pins 40' ai that send output signals from the sensor chip 16 and provide power to the sensor chip 16.

the sensor chip 16 is directly fixed to the surface of the base 64 facing the surface to be bonded of the sensor chip 16. A recess 64Ga for forming the adhesive layer 50 is formed in a portion of the base 64 facing the surface to be bonded of the sensor chip 16. The diameter of the inner peripheral surface forming the recess 64Ga is set larger than the length of the diagonal line of the sensor chip 16. The recess 64Ga has a predetermined depth Dp such that the thickness of the adhesive layer 50 is 5 μm or more, for example.

The adhesive layer 50 is formed in the recess 64Ga and is formed in a portion where an extended surface of the base 64 adjacent to an end surface of the sensor chip 16 intersects with an outer peripheral edge of the sensor chip 16 facing the end surface. The portion of the base 64 where the extended surface of the end surface adjacent to the sensor chip 16 intersects the outer peripheral edge of the sensor chip 16 facing the end surface is formed of, for example, excess adhesive that has overflowed from the inside of the recess 64 Ga.

the terminal pins 40' ai are supported by the through holes of the base 64 via the sealing glass 56. The terminal pins 40' ai are connected to the sensor chip 16 by bonding wires Wi.

In the example shown in fig. 6A, the base 64 is formed of a metal material, but the present invention is not limited to this example, and for example, as shown in fig. 6B, the base 64' may be formed of a resin material.

The sensor chip 16 is directly fixed to the surface of the base 64' facing the surface to be bonded of the sensor chip 16. A recess 64 'Gb for forming the adhesive layer 50 is formed in a portion of the base 64' facing the surface to be bonded of the sensor chip 16. One end of the recess 64' Gb opens toward the bonded surface of the sensor chip 16. The recess 64' Gb has a predetermined depth Dp such that the thickness of the adhesive layer 50 is 5 μm or more, for example. The diameter of the inner peripheral surface of the base 64 'where the recess 64' Gb is formed is set slightly larger than the length of the diagonal line of the sensor chip 16.

The adhesive layer 50 is formed in the recess 64 'Gb and in a portion where the extended surface of the end surface of the base 64' adjacent to the sensor chip 16 intersects with the outer peripheral edge of the sensor chip 16 facing the end surface. The portion of the base 54 'where the extended surface of the end surface adjacent to the sensor chip 16 intersects the outer peripheral edge of the sensor chip 16 facing the end surface is formed of, for example, excess adhesive that overflows from the recess 64' Gb. By setting the amount of adhesive applied to the recess 64 ' Gb to be equal to or greater than the internal volume of the recess 64 ' Gb as if the adhesive were to overflow from the recess 64 ' Gb, the adhesive layer 50 having a uniform thickness is formed, and it is not necessary to accurately control the amount of adhesive applied.

In the above-described example of the pressure sensor of the present invention, the amount of adhesive applied is set to be equal to or greater than the internal volume of the recess 18R, such as to overflow from the inside of the recess 18R, but the present invention is not limited to this example, and the sensor chip 16 may be adhered by applying the adhesive to a portion of the substantially central portion in the cavity of the recess 18R so that the height of the applied adhesive from the bottom to the top of the recess is equal to or greater than the depth of the recess 18R. In this case, a cavity is formed in the concave portion around the adhesive applied to the central portion for bonding the sensor chip.