CN116086685A - Pressure sensor - Google Patents

Abstract

The invention reduces deformation of a sensor diaphragm caused by heat transfer from a fluid to be measured, and miniaturizes a supporting structure of a sensor element. A sensor element (40) of a pressure sensor is provided with: a sensor diaphragm (41) deformed by the pressure of the fluid to be measured flowing into the inflow space (R2), and an annular support portion (42) for supporting the sensor diaphragm. A support structure (70) for supporting the sensor element (40) is provided with a plate-like member (72) that covers the sensor diaphragm from the inflow space (R2) side, and a spacer (73) that is disposed between the sensor element and the plate-like member. The plate-like member (72) is provided with an introduction hole (72A) for introducing the fluid to be measured to the sensor diaphragm side, and the spacer is provided with an annular part (73A) fixed to the support part; an opposing portion (73B) extending from the annular portion and opposing the introduction hole; and a through hole (73C) overlapping the sensor diaphragm on the inner side of the annular part (73A) in a plan view.

Description

Pressure sensor

Technical Field

The present invention relates to a pressure sensor.

Background

Pressure sensors are known which measure the pressure of a fluid to be measured using a sensor diaphragm. As disclosed in patent document 1 (in particular, fig. 14 of patent document 1), such a pressure sensor includes: a sensor package; a sensor diaphragm type sensor element disposed in the sensor package; and a base member (plate-like member) that covers the sensor diaphragm and has a through hole in the center. In the pressure sensor disclosed in patent document 1, a spacer that surrounds the sensor diaphragm in a plan view is provided between the sensor element and the base member. The base member and the spacer are part of a support structure that supports the sensor element.

Prior art literature

Patent literature

Patent document 1: japanese patent laid-open No. 2020-30203

Disclosure of Invention

Problems to be solved by the invention

In the pressure sensor disclosed in patent document 1, in order to prevent deformation of the sensor diaphragm due to heat transfer from the fluid to be measured, the spacer is thickened, and the distance between the sensor diaphragm and the base member is increased. However, the support structure of the sensor element including the spacers is correspondingly enlarged with the thickened spacers.

The present invention has been made in view of the above-described problems, and an object of the present invention is to reduce deformation of a sensor diaphragm due to heat transfer from a fluid to be measured and to miniaturize a support structure of a sensor element.

Technical means for solving the problems

The pressure sensor according to the present invention for solving the above problems includes: a package forming an inflow space into which a fluid to be measured flows; a sensor element disposed in the package, the sensor element including a sensor diaphragm deformed by a pressure of the fluid to be measured flowing into the inflow space, and an annular support portion surrounding the sensor diaphragm and supporting the sensor diaphragm; and a support structure that supports the sensor element in a direction of the sensor diaphragm toward the inflow space side, the support structure including: a plate-like member that covers the sensor diaphragm from the inflow space side; and a spacer disposed between the sensor element and the plate-like member, the plate-like member having an introduction hole provided at a position overlapping the sensor diaphragm in a plan view, the spacer including: an annular portion fixed to the support portion; an opposing portion that protrudes from the annular portion and faces the introduction hole, and that comes into contact with the fluid to be measured from the introduction hole; and a through hole that overlaps the sensor diaphragm inside the annular portion in a plan view, and guides the fluid to be measured that contacts the opposing portion to the sensor diaphragm.

The support structure may include a support membrane fixed to the package and supporting the sensor element with the spacer interposed therebetween, the support membrane including: an opening; a 1 st surface of the plate-like member which faces the inflow space side and is fixed in a state of covering the opening; and a 2 nd surface opposite to the 1 st surface, to which the annular portion of the spacer is fixed.

The plate-like member may include a plurality of introduction holes provided at positions overlapping with an outer edge portion of the sensor diaphragm in a plan view, and the spacer may include a plurality of opposing portions extending from the annular portion and opposing the plurality of introduction holes, respectively, as the opposing portions, and the through hole may extend from a center of an area inside the annular portion across between the plurality of opposing portions, respectively.

The facing portion may include a central portion and a plurality of connection portions extending from the central portion and connected to the annular portion, and the spacer may include a plurality of through holes overlapping the sensor diaphragm on an inner side of the annular portion as the through holes, the plurality of through holes being arranged between the plurality of connection portions, respectively.

The introduction hole may be opposed to the central portion.

The introduction hole may be opposite to the connection portion.

The thermal expansion coefficient of the spacer may be the same as that of the sensor element.

ADVANTAGEOUS EFFECTS OF INVENTION

According to the present invention, deformation of the sensor membrane due to heat transfer from the fluid to be measured can be reduced, and the support structure of the sensor element can be miniaturized.

Drawings

Fig. 1 is a longitudinal sectional view of a pressure sensor according to embodiment 1 of the present invention.

Fig. 2 is a perspective cross-sectional view of a sensor element and a support structure of the pressure sensor of fig. 1.

Fig. 3 is an exploded perspective view of the support structure of fig. 1.

Fig. 4 is an exploded perspective view of the support structure of fig. 1.

Fig. 5 is a perspective cross-sectional view of a sensor element and a support structure of the pressure sensor of embodiment 2.

Fig. 6 is an exploded perspective view of the support structure of fig. 5.

Fig. 7 is a perspective cross-sectional view of a sensor element and a support structure of the pressure sensor of embodiment 3.

Fig. 8 is an exploded perspective view of the support structure of fig. 7.

Detailed Description

< embodiment 1 >

A pressure sensor 10 according to embodiment 1 of the present invention will be described with reference to fig. 1 to 4. In fig. 1, the thicknesses of the sensor membrane 41, the support portion 42, the movable electrode 45, and the fixed electrode 46 constituting the sensor element 40 described later, and the thicknesses of the support membrane 71 of the support structure 70 described later are exaggerated as compared with fig. 2. The plan view described below refers to a state in which the pressure sensor 10 (in particular, a sensor diaphragm 41 described below) is viewed along the central axis direction of the pressure sensor 10, and here refers to a state viewed from above in fig. 1. In fig. 2, the cross section is indicated by dots, not by hatching as in fig. 1 (the same applies to fig. 5 and 7). In addition, a plurality of elements having the same function or the like may be given symbols only in a part thereof. The vertical direction shown in the drawings is for convenience and does not indicate the actual use state of the pressure sensor 10. The pressure sensor 10 may be disposed with the upper side in fig. 1 as the ground side.

As shown in fig. 1, the pressure sensor 10 is provided with a package 20, a baffle 30, a sensor element 40, a contact pad 50, an electrode member 60, and a support structure 70. The pressure sensor 10 is configured as a vacuum gauge for measuring the pressure of the fluid L to be measured including the residual gas in the vacuum chamber.

The package 20 includes the 1 st package member 21, the 2 nd package member 22, and the 3 rd package member 23, and houses the sensor element 40, the contact pad 50, the support structure 70, and the like. The package 20 forms an introduction path R1 through which the fluid L to be measured is introduced, an inflow space R2 through which the fluid L to be measured flows from the introduction path R1, and a vacuum chamber R3 in which a vacuum pressure that is a pressure of the fluid L to be measured and that is a pressure of the inflow space R2 is sealed. The package 20 is formed of a metal such as inconel.

The 1 st packing member 21 has a funnel shape that divides the introduction path R1 by a cylindrical small diameter portion and divides the inflow space R2 by a cup-shaped large diameter portion together with the support structure 70. A cylindrical 2 nd sealing member 22 is joined to the lower end of the 1 st sealing member 21 by welding or the like with a peripheral edge portion of a support film 71 described later of the support structure 70 interposed therebetween. A 3 rd sealing member 23 having a disk shape is bonded to the lower end of the 2 nd sealing member 22 by welding or the like. The 3 rd package member 23, together with the 2 nd package member 22, the sensor element 40 and the support structure 70, divide the vacuum chamber R3.

The barrier 30 is fixed to the 1 st sealing member 21 by a fixing member or the like not shown. The baffle 30 changes the flow of the fluid L to be measured flowing into the inflow space R2 through the introduction path R1 to the outer circumferential direction of the package 20.

The sensor element 40 detects the pressure of the fluid L to be measured by converting the pressure into an electrical signal. The sensor element 40 is disposed within the package 20 and supported by the support structure 70. As shown in fig. 1 and 2, the sensor element 40 includes a circular sensor diaphragm 41 and an annular support portion 42 surrounding the sensor diaphragm 41 and supporting the sensor diaphragm 41. The upper surface of the sensor diaphragm 41 facing the inflow space R2 is a pressure receiving surface that receives the pressure of the fluid L to be measured. The fluid L to be measured flowing into the inflow space R2 passes through the support structure 70 as will be described later, and the pressure thereof presses the pressure receiving surface of the sensor diaphragm 41, thereby deforming the sensor diaphragm 41.

The sensor diaphragm 41 and the support portion 42 are integrally formed as one member. The sensor element 40 further has a plate 43 fixed to the support portion 42 by welding or the like. The plate 43 forms a capacity chamber C together with the sensor diaphragm 41 and the support portion 42. The capacity chamber C is connected to the vacuum chamber R3 through a through hole (not shown) formed in the plate 43, and is evacuated. The sensor diaphragm 41, the support portion 42, and the plate 43 are made of sapphire or the like.

The sensor element 40 includes a movable electrode 45 formed on a measurement surface opposite to the pressure receiving surface of the sensor diaphragm 41, and a fixed electrode 46 formed on the plate 43. The movable electrode 45 is opposite to the fixed electrode 46. The shape and number of the movable electrodes 45 and the fixed electrodes 46 are arbitrary.

By the deformation of the sensor diaphragm 41, the movable electrode 45 is displaced, and the distance between the movable electrode 45 and the fixed electrode 46 is changed. That is, the capacitance of the capacitor formed by the movable electrode 45 and the fixed electrode 46 changes. The sensor element 40 outputs an electrical signal indicating a change in the capacitance. In this way, the sensor element 40 converts the deformation of the sensor diaphragm 41, i.e., the pressure of the fluid L to be measured, into an electrical signal. The electric signal is, for example, a voltage signal having a voltage value corresponding to the pressure of the fluid L to be measured.

As shown in fig. 1, a plurality of contact pads 50 are formed on the surface of the plate 43 opposite to the surface on which the fixed electrode 46 is formed. The plurality of contact pads 50 are electrically connected to the movable electrode 45 or the fixed electrode 46 through various wiring not shown. The plurality of contact pads 50 are used for extracting an electrical signal indicating the pressure of the fluid L to be measured, which is outputted from the sensor element 40.

A plurality of electrode members 60 are connected to each of the plurality of contact pads 50, and the plurality of electrode members 60 are configured to take out an electric signal indicating the pressure of the fluid L to be measured to the outside of the package 20. Each electrode member 60 penetrates the 3 rd package member 23 in the package 20, and is fixed to the 3 rd package member 23 by a not-shown seal. Each electrode member 60 includes: the conductive pin 61 for transmitting the electric signal, a cylindrical shielding portion 62 surrounding the conductive pin 61, and a contact spring 63 connecting the conductive pin 61 and the contact pad 50. The conductive pin 61 is fixed to the shield 62 by a seal or the like in a state of passing through the inside of the shield 62. The electric signal is transmitted through the contact pad 50, the contact spring 63, and the conductive pin 61, and as a result, is output to the outside of the pressure sensor 10.

As shown in fig. 1 and 2, the support structure 70 supports the sensor element 40 in the package 20 in a direction of the sensor diaphragm 41 toward the inflow space R2 side. As shown in fig. 1 to 4, the support structure 70 includes a support membrane 71, a plate-like member 72, and a spacer 73. The support diaphragm 71, the plate-like member 72, and the spacers 73 are formed of sapphire or the like. The central axes of the support diaphragm 71, the plate-like member 72, the spacer 73, the sensor element 40, and the pressure sensor 10 coincide.

The support diaphragm 71 supports the sensor element 40 via the spacer 73. As shown in fig. 1, the peripheral edge portion of the support film 71 is sandwiched by the 1 st and 2 nd package members 21 and 22 of the package 20, and is thereby fixed in the package 20.

As shown in fig. 1 to 4, a plate-like member 72 is fixed to a 1 st surface 71A of the support diaphragm 71 facing the inflow space R2 side by welding or the like. A spacer 73 is fixed to a 2 nd surface 71B of the support film 71 opposite to the 1 st surface 71A by welding or the like. The sensor element 40 is fixed to the spacer 73 by welding or the like. The spacer 73 is disposed between the plate-like member 72 and the sensor element 40, more specifically, between the support diaphragm 71 and the sensor element 40. An opening 71C is provided in the center of the support diaphragm 71. The opening 71C is larger than the sensor diaphragm 41 in plan view, and overlaps the sensor diaphragm 41 so as to include the entire sensor diaphragm 41 inside. The opening 71C may have a shape corresponding to the sensor diaphragm 41 in plan view.

The plate-like member 72 is formed in a flat plate shape, facing the inflow space R2. By fixing the outer edge portion of the plate-like member 72 to the peripheral portion of the opening 71C of the support diaphragm 71, the plate-like member 72 covers the opening 71C of the support diaphragm 71.

The plate-like member 72 includes four introduction holes 72A, and these introduction holes 72A communicate the opening 71C with the inflow space R2, and introduce the fluid L to be measured flowing into the inflow space R2 to the sensor diaphragm 41 side. The four introduction holes 72A are through holes extending in the thickness direction of the plate-like member 72. As shown in fig. 2, the introduction hole 72A is provided at a position overlapping the outer edge of the sensor diaphragm 41 in a plan view.

As shown in fig. 1 to 4, the spacer 73 ensures the interval between the plate-like member 72 and the sensor element 40. The spacer 73 includes an annular portion 73A fixed to the sensor element 40 and a plurality of (4 in this case) opposing portions 73B opposing the plurality of introduction holes 72A. The plurality of opposing portions 73B protrude inward of the annular portion 73A from the inner peripheral wall of the annular portion 73A. The spacer 73 further includes a through hole 73C provided inside the annular portion 73A and adjacent to the opposing portion 73B. The through hole 73C is formed in a substantially cross shape, and has a shape that spans between the plurality of opposing portions 73B from the center of the region inside the annular portion 73A, that is, the region surrounded by the annular portion 73A.

An end surface (upper end surface) of the annular portion 73A on the support diaphragm 71 side is fixed to a peripheral portion of the opening 71C of the support diaphragm 71. The end surface (lower end surface) of the annular portion 73A on the sensor element 40 side is fixed to the support portion 42 of the sensor element 40. The spacer 73 and the plate-like member 72 sandwich the support diaphragm 71 and also function as a support base for supporting the sensor element 40. The spacer 73 covers the opening 71C together with the sensor element 40 from the vacuum chamber R3 side.

The opposing portion 73B and the through hole 73C overlap the sensor membrane 41 of the sensor element 40 in a plan view. The through hole 73C exposes a part of the sensor diaphragm 41, that is, a part of the sensor diaphragm 41 not covered by the opposing portion 73B of the spacer 73, to the inflow space R2 side together with the opening 71C. The plate-like member 72 covering the opening 71C covers the opposing portion 73B, the through hole 73C, and the sensor diaphragm 41 from the inflow space R2 side.

As shown by the thick line arrow in fig. 2, the fluid L to be measured flowing into the inflow space R2 passes through the introduction hole 72A of the plate-like member 72, and then passes through the opening 71C of the support diaphragm 71 to come into contact with the opposing portion 73B of the spacer 73. The opposing portion 73B guides the fluid L to be measured that contacts the opposing portion 73B to the adjacent through hole 73C. The through hole 73C guides the fluid L to be measured to the sensor membrane 41 of the sensor element 40. The sensor diaphragm 41 deforms due to the pressure of the guided fluid L to be measured.

In this embodiment, the fluid L to be measured passing through the introduction hole 72A of the plate-like member 72 contacts the opposing portion 73B, and thereby heat exchange is performed between the fluid L to be measured and the opposing portion 73B. This reduces the temperature drop (when the measured fluid L is at a high temperature) or rise (when the measured fluid L is at a low temperature) of the measured fluid L, and reduces the deformation of the sensor diaphragm 41 due to the heat transfer from the measured fluid L. This can reduce the occurrence of errors in the output signal due to hysteresis, displacement, or the like of the sensor diaphragm 41. Further, if the spacer 73 does not include the opposing portion 73B, the spacer 73 needs to be thickened so that the temperature of the fluid L to be measured when reaching the sensor diaphragm 41 is sufficiently lowered. In this embodiment, the fluid L to be measured contacts the opposing portion 73B, and therefore the thickness of the spacer 73 can be reduced as compared with the case where the opposing portion 73B is not provided. Thus, the support structure 70 and thus the pressure sensor 10 as a whole are miniaturized. As described above, according to the present embodiment, the deformation of the sensor diaphragm 41 due to the heat transfer from the fluid L to be measured can be reduced, and the support structure 70 for supporting the sensor element 40 can be miniaturized.

In this embodiment, the through hole 73C has a shape that spans between the plurality of opposing portions 73B from the center of the region inside the annular portion 73A, and is formed large. Therefore, in the cleaning in the manufacturing process of the pressure sensor 10 or the like, the cleaning liquid is easily separated from the support structure 70. The number of the introduction holes 72A and the opposing portions 73B may be arbitrary or may be one.

In this embodiment, the through hole 73C of the spacer 73 overlaps the sensor membrane 41 in a plan view. On the other hand, it is also conceivable to reduce the through hole 73C to be provided at a position outside the sensor diaphragm 41 of the spacer 73. In this case, it is necessary to provide a guide hole for guiding the fluid L to be measured from the through hole 73C to the sensor diaphragm 41 in the support portion 42 of the sensor element 40. However, when the sensor element 40 is bonded to the spacer 73, alignment of the guide hole and the through hole 73C becomes difficult. In this embodiment, since the through hole 73C overlaps the sensor diaphragm 41 in a plan view, it is not necessary to provide a guide hole or the like in the support portion 42, and the trouble of the alignment is eliminated, and the manufacturing cost of the pressure sensor 10 can be suppressed accordingly. In addition, since the opposing portion 73B of the spacer 73 is larger than the introduction hole 72A of the plate-like member 72 in plan view and the introduction hole 72A is located in the opposing portion 73B, some positional displacement between the spacer 73 and the plate-like member 72 is also absorbed.

In this embodiment, the end surface 72B (see fig. 4) of the plate-like member 72 fixed to the support diaphragm 71 protrudes from the other surface of the plate-like member 72, particularly the surface of the lower end peripheral portion of the introduction hole 72A. Further, an end surface 73D (see fig. 3) of the annular portion 73A of the spacer 73 fixed to the support film 71 protrudes from a surface (upper end surface) of the opposing portion 73B on the support film 71 side. Therefore, even if the support film 71 is thinned, the interval between the introduction hole 72A and the opposing portion 73B can be ensured. This ensures a flow rate when the fluid L to be measured flowing from the introduction hole 72A of the plate member 72 to the through hole 73C contacts the opposing portion 73B of the spacer 73, flows between the plate member 72 and the opposing portion 73B. The plate-like member 72 and the spacer 73 may protrude from one end surface.

The materials of the sensor element 40 (in particular, the sensor diaphragm 41, the support portion 42, and the plate 43), the support diaphragm 71, the plate-like member 72, and the spacer 73 are arbitrary, but the same materials or the like may be used so that the thermal expansion coefficients of the respective members are substantially equal. This is to prevent the following: if the thermal expansion coefficients are different, the degree of expansion of the respective members is different at the time of self-heating at the time of use of the pressure sensor 10, thereby causing deformation of the sensor diaphragm 41. In particular, by making the respective thermal expansion coefficients of the sensor element 40 and the spacer 73 to which the sensor element 40 is directly fixed substantially equal, the deformation of the sensor diaphragm 41 can be reduced.

< embodiment 2 >

In embodiment 2, as shown in fig. 5 and 6, the support structure 70 is modified to a support structure 170. More specifically, the plate-like member 72 is changed to the plate-like member 172, and the spacer 73 is changed to the spacer 173. The other parts are the same as those of embodiment 1, and therefore the same reference numerals are given thereto, and detailed description thereof will be omitted.

The plate member 172 includes one introduction hole 172A for introducing the fluid L to be measured flowing into the inflow space R2 to the sensor diaphragm 41 side instead of the plurality of introduction holes 72A. The introduction hole 172A is formed in the center of the plate-like member 72.

The spacer 173 includes: an annular portion 173A having the same function and shape as the annular portion 73A of embodiment 1; and an opposing portion 173B having the same function as the opposing portion 73B of embodiment 1 but a different shape. The opposing portion 173B includes: a central portion 173BA located at the center of the region inside the annular portion 173A in plan view; and a plurality of connection portions 173BB radially extending from the central portion 173BA and connected to the annular portion 173A. In the present embodiment, four connection portions 173BB are provided, and the opposing portions 173B are formed in a substantially cross shape, but the number of connection portions 173BB is arbitrary. The center portion 173BA faces the introduction hole 172A of the plate member 172.

The spacer 173 includes a plurality of through holes 173C having the same function as the through holes 73C of embodiment 1. The plurality of through holes 173C overlap the sensor diaphragm 41 on the inner side of the annular portion 173A in a plan view, and guide the fluid L to be measured, which contacts the opposing portion 173B, more specifically, the center portion 173BA, to the sensor diaphragm 41. The plurality of through holes 173C are disposed between the plurality of connection portions 173BB, respectively. In other words, the through holes 173C and the connection portions 173BB are alternately arranged along the circumferential direction of the spacer.

In this embodiment, the fluid L to be measured passing through the introduction hole 172A of the plate member 172 contacts the center portion 173BA of the opposing portion 173B, and heat exchange is performed between the fluid L to be measured and the opposing portion 173B. Therefore, in the present embodiment as well, as in embodiment 1, deformation of the sensor diaphragm 41 due to heat transfer from the fluid L to be measured can be reduced, and the support structure 170 for supporting the sensor element 40 can be miniaturized.

In this embodiment, the opposing portion 173B includes a central portion 173BA and a plurality of connection portions 173BB extending from the central portion 173BA and connected to the annular portion 173A. Therefore, the opening area of the through hole 173C of the spacer 173 is smaller than that of embodiment 1, and rigidity is added to the spacer 173 accordingly. The shape of the opposing portion 173B, that is, the shape, position, and number of the through holes 173C can be derived by topology analysis or the like. The shape of the optimal opposing portion 173B that can ensure the rigidity of the spacer 173 is derived by topology analysis or the like.

< embodiment 3 >

In embodiment 3, as shown in fig. 7 and 8, the support structure 70 is changed to a support structure 270. The support structure 270 is a structure in which the spacer 73 of the support structure 70 of embodiment 1 is changed to the spacer 173 of embodiment 2. In the present embodiment, the four introduction holes 72A of the plate-like member 72 are respectively opposed to the four connection portions 173BB of the opposed portions 173B of the spacers 173. The fluid L to be measured is in contact with the connection portion 173BB to exchange heat, and reaches the sensor membrane 41 of the sensor element 40 through the through hole 173C of the spacer 173. Even in this embodiment, the same effects as those of embodiment 1 and embodiment 2 can be obtained appropriately.

< modification >

Various modifications may be made to the above embodiments. For example, the shape of each member, particularly the shape of the spacer, may be changed as appropriate. For example, the number of connecting portions of the opposing portions of the spacer is arbitrary. The plate-like member may be provided with an introduction hole with respect to at least a part of the plurality of connection portions. The position of the introduction hole may be a position facing the facing portion. The guide holes may be provided so as to face the central portion and the connecting portion, respectively. The sensing system of the pressure sensor in the above embodiment is a capacitance type, but the present invention is not limited to this sensing system. The present invention can be applied to a pressure sensor using a strain gauge formed by bonding or sputtering a resistance gauge or a semiconductor piezoresistive system, for example. That is, the present invention is applicable to all pressure sensors provided with a sensing system for converting deformation of a sensor diaphragm into an electrical signal. The pressure sensor may be used in various places other than the film forming apparatus.

< scope of the invention >

The present invention has been described above with reference to the embodiments and modifications, but the present invention is not limited to the embodiments and modifications. For example, the present invention includes various modifications to the above-described embodiments and modifications within the scope of the technical idea of the present invention as will be understood by those skilled in the art. The respective configurations listed in the above embodiments and modifications may be appropriately combined within a range where no contradiction exists.

Symbol description

10 … pressure sensor, 20 … package, 21 … package 1, 22 … package 2, 23 … package 3, 30 … baffle, 40 … sensor element, 41 … sensor diaphragm, 42 … support, 43 … plate, 45 … movable electrode, 46 … fixed electrode, 50 … contact pad, 60 … electrode member, 61 … conductive pin, 62 … shield, 63 … contact spring, 70 … support structure, 71 … support diaphragm, 71A … side 1, 71B … side 2, 71C … opening the device comprises a 72- … plate-shaped member, a 72-A … introduction hole, a 72-B … end surface, a 73- … spacer, a 73-A … annular portion, a 73-B … opposite portion, a 73-C … through hole, a 73-D … end surface, a 170- … supporting structure, a 172- … plate-shaped member, a 172-A … introduction hole, a 173-A … spacer, a 173-A … annular portion, a 173-B … opposite portion, a 173-BA … central portion, a 173-BB … connecting portion, a 173-C … through hole, a 270- … supporting structure, a C … capacity chamber, a L … measured fluid, a R1 … introduction path, a R2 … inflow space and a R3 … vacuum chamber.

Claims (10)

1. A pressure sensor, comprising:

a package forming an inflow space into which a fluid to be measured flows;

a sensor element disposed in the package, the sensor element including a sensor diaphragm deformed by a pressure of the fluid to be measured flowing into the inflow space, and an annular support portion surrounding the sensor diaphragm and supporting the sensor diaphragm; and

a support structure for supporting the sensor element in a direction of the sensor diaphragm toward the inflow space side,

the support structure is provided with: a plate-like member that covers the sensor diaphragm from the inflow space side; and a spacer arranged between the sensor element and the plate-like member,

the plate-like member includes an introduction hole provided at a position overlapping the sensor diaphragm in a plan view, for introducing the fluid to be measured to the sensor diaphragm side,

the spacer is provided with: an annular portion fixed to the support portion; an opposing portion that protrudes from the annular portion and faces the introduction hole, and that comes into contact with the fluid to be measured from the introduction hole; and a through hole overlapping the sensor diaphragm on the inner side of the annular portion in a plan view, and guiding the fluid to be measured in contact with the opposing portion to the sensor diaphragm.

2. The pressure sensor of claim 1, wherein the pressure sensor is configured to,

the support structure includes a support membrane fixed to the package and supporting the sensor element via the spacer,

the support membrane is provided with: an opening; a 1 st surface facing the inflow space side, to which the plate-like member is fixed in a state of covering the opening; and a 2 nd surface to which the annular portion of the spacer is fixed, the annular portion being opposite to the 1 st surface.

3. A pressure sensor according to claim 1 or 2, characterized in that,

the plate-like member includes a plurality of introduction holes as the introduction holes provided at positions overlapping with an outer edge portion of the sensor diaphragm in a plan view,

the spacer includes a plurality of opposing portions extending from the annular portion and opposing the plurality of introduction holes, respectively, as the opposing portions,

the through hole spans between each of the plurality of opposing portions from a center of an area inside the annular portion.

4. A pressure sensor according to claim 1 or 2, characterized in that,

the opposite portion includes a central portion and a plurality of connection portions extending from the central portion and connected to the annular portion,

the spacer includes a plurality of through holes overlapping the sensor diaphragm on the inner side of the annular portion in a plan view,

the plurality of through holes are arranged between the plurality of connection portions.

5. The pressure sensor of claim 4, wherein the pressure sensor is configured to,

the introduction hole is opposed to the central portion.

6. The pressure sensor of claim 4, wherein the pressure sensor is configured to,

the introduction hole is opposite to the connection portion.

7. A pressure sensor according to claim 1 or 2, characterized in that,

the spacer has a thermal expansion coefficient identical to that of the sensor element.

8. A pressure sensor according to claim 3, wherein,

the spacer has a thermal expansion coefficient identical to that of the sensor element.

9. The pressure sensor of claim 4, wherein the pressure sensor is configured to,

the spacer has a thermal expansion coefficient identical to that of the sensor element.

10. A pressure sensor according to claim 5 or 6, characterized in that,

the spacer has a thermal expansion coefficient identical to that of the sensor element.

Images