JP2022034155A - Pressure sensor - Google Patents

Abstract

To provide a pressure sensor that can reduce bolting shift without increasing the size of a base body.SOLUTION: A pressure sensor comprises: a base body that is overlapped on a mounting seat for a sensor with metal O-rings (seal members) therebetween and fastened by bolts for mounting; a sensor chip 42 that has a first semiconductor diaphragm 72 and is adhered to an outer end of the base body opposite to the mounting seat for a sensor; pressure receiving chambers that are provided on an inner end of the base body opposite to the mounting seat for a sensor and have barrier diaphragms that become parts of walls; and a primary-side pressure guide path, a secondary-side pressure guide path, a first passage hole 55, and a second passage hole (pressure guide paths) that are formed to extend from the pressure receiving chambers to the inside of the sensor chip 42 and filled with liquid for pressure transmission. Inlets for injecting the liquid for pressure transmission into the pressure guide paths are provided in the sensor chip 42.SELECTED DRAWING: Figure 4

Description

The present invention relates to a pressure sensor including a base body bolted to a sensor mounting seat and a sensor chip bonded to the base body.

Conventionally, when measuring the flow rate of the fluid to be measured, for example, as described in Patent Document 1, the pressure of the fluid to be measured may be detected by a pressure sensor. As the pressure sensor for detecting this pressure, for example, there is one configured as shown in FIG. The pressure sensor 1 shown in FIG. 6 includes a base body 4 fastened to a sensor mounting seat 2 by a plurality of mounting bolts 3, and a sensor chip 5 adhered to an outer end portion of the base body 4.

The sensor mounting seat 2 has a primary side pressure guiding port 2a and a secondary side pressure guiding port 2b to which the pressure of the fluid to be measured 6 is guided.
The base body 4 has a primary pressure receiving chamber 8 in which the primary pressure barrier diaphragm 7 facing the primary pressure guiding port 2a is a part of the wall, and a secondary pressure barrier diaphragm 9 facing the secondary pressure guiding port 2b. The secondary pressure receiving chamber 10 that is a part of the wall, the primary pressure guiding path 11 extending from the primary pressure receiving chamber 8 to the sensor chip 5, and the secondary pressure guiding path 11 extending from the secondary pressure receiving chamber 10 to the sensor chip 5. It has a road 12 and the like. The primary side pressure receiving chamber 8, the secondary side pressure receiving chamber 10, the primary side pressure guiding passage 11, and the secondary side pressure guiding passage 12 are filled with the liquid 13 for pressure transmission.

The base body 4 is fastened to the sensor mounting seat 2 by a plurality of mounting bolts 3 with the metal O-rings 14 and 15 sandwiched between the sensor mounting seat 2 and the sensor mounting seat 2. The metal O-rings 14 and 15 exhibit a high degree of sealing property even under harsh conditions such as high temperature and high pressure, and maintain the sealing property even in an ultra-high vacuum. Further, since it is easier to install and remove as compared with a connecting means such as welding, maintenance and replacement of the pressure sensor 1 can be easily performed.

The base body 4 is provided with a first sealing hole 16 for injecting the liquid 13 for pressure transmission into the primary side pressure guiding path 11, and the secondary side pressure guiding path 12 for pressure transmission. A second sealing hole 17 is formed for injecting the liquid 13 of the above.

Japanese Unexamined Patent Publication No. 2019-128168

In the conventional pressure sensor 1 shown in FIG. 6, the mounting bolt 3 is tightened so that the metal O-rings 14 and 15 are sandwiched between the sensor mounting seat 2 and the base body 4 and plastically deformed. When the base body 4 is fastened to the sensor mounting seat 2 with the mounting bolts 3 in this way, a large stress is generated around the metal O-rings 14 and 15, and the base body 4 is deformed. In particular, in the liquid-filled pressure sensor 1 as shown in FIG. 6, since the first and second sealing holes 16 and 17 are formed in the base body 4, the rigidity of the base body 4 tends to decrease. ..

The deformation of the base body 4 extends to the adhesive portion 18 to which the sensor chip 5 is adhered. When the sensor chip 5 has high sensitivity, it is affected by the distortion of the adhesive portion 18, so that the sensor output shifts to the high voltage side or the low voltage side depending on the tightening force of the mounting bolt 3. In the following, such a shift of the sensor output is simply referred to as a “bolting shift”.

To reduce the bolting shift, it is effective to increase the thickness of the base body 4. However, if the base body 4 is formed thick, the pressure sensor 1 becomes large and may interfere with peripheral devices.
In recent years, there is an increasing need for high precision and miniaturization of differential pressure type mass flow controllers for the semiconductor market, and further high precision and miniaturization are required for the pressure sensor, which is one of its components. There is.

An object of the present invention is to provide a pressure sensor capable of reducing bolting shift without increasing the size of the base body.

In order to achieve this object, the pressure sensor according to the present invention is a base body that is superposed on a sensor mounting seat having a pressure guiding port through which the pressure of the fluid to be measured is transmitted via a seal member and fastened by a fastening member. A sensor chip having a semiconductor diaphragm and bonded to an outer end portion of the base body opposite to the sensor mounting seat, and an inner end portion of the base body facing the sensor mounting seat. The barrier diaphragm that receives the pressure of the fluid to be measured is formed so as to be a part of the wall so as to extend from the pressure receiving chamber to the inside of the sensor chip and the pressure receiving chamber separated from the fluid to be measured. A pressure guiding path formed and filled with a liquid for pressure transmission is provided, and an injection port for injecting the liquid into the pressure guiding path is provided in the sensor chip.

In the present invention, in the pressure sensor, the sensor chip has a first pressure chamber and a second pressure chamber partitioned by the semiconductor diaphragm, and a first passage hole and a first passage hole extending in the thickness direction of the semiconductor diaphragm. The second passage hole, the first communication passage that communicates the first passage hole and the first pressure chamber, and the second passage that communicates the second passage hole and the second pressure chamber. The barrier diaphragm, the pressure receiving chamber, and the pressure guiding path are provided so as to be paired with each other, and the barrier diaphragm, the pressure receiving chamber, and the pressure guiding path are provided from one of the barrier diaphragms, the pressure receiving chamber, and the pressure guiding path. A first pressure transmission unit is connected to one end of the first passage hole, and a second pressure transmission unit including the other barrier diaphragm, the pressure receiving chamber, and the pressure guiding path is the second passage. Connected to one end of the hole, the inlet is composed of the other end of the first passage hole and the other end of the second passage hole, and the liquid transmits the first and second pressures. It may be closed by a plug member while being injected into the portion and the inside of the sensor chip.

According to the present invention, since it is not necessary to provide a sealing hole for injecting a liquid for pressure transmission into the base body, it is possible to suppress a decrease in rigidity of the base body caused by the provision of the sealing hole. It will be possible. Therefore, it is possible to suppress the deformation of the sensor chip due to the deformation of the base body when the base body is fastened to the sensor mounting seat with the fastening member. In order to suppress the distortion of the base body in this way, it is not necessary to form the base body thick.
Therefore, it is possible to provide a pressure sensor that can reduce the bolting shift without increasing the size of the base body.

FIG. 1 is a cross-sectional view of a mass flow controller provided with a pressure sensor according to the present invention. FIG. 2 is a cross-sectional view of a part of the pressure sensor. FIG. 3 is a plan view of the sensor chip. FIG. 4 is a sectional view taken along line IV-IV in FIG. FIG. 5 is a sectional view taken along line VV in FIG. FIG. 6 is a cross-sectional view of a part of the conventional pressure sensor.

Hereinafter, an embodiment of the pressure sensor according to the present invention will be described in detail with reference to FIGS. 1 to 5. In this embodiment, an example of applying the present invention to a pressure sensor used for measuring the flow rate of the fluid to be measured is shown.

The pressure sensor 21 shown in FIG. 1 is attached to the laminar flow element 23 of the differential pressure type mass flow controller 22. The differential pressure type mass flow controller 22 includes a passage forming member 25 that forms a fluid passage 24, a valve 26 that adjusts the flow rate of the fluid, and a laminar flow element 23 in which the fluid flows as a laminar flow. A pressure sensor 21 according to the present invention is attached to the laminar flow element 23 in order to detect the pressure of the fluid on the upstream side and the pressure of the fluid on the downstream side in the laminar flow element.

As shown in FIG. 2, the pressure sensor 21 is attached to the sensor mounting seat 31 of the laminar flow element 23. The sensor mounting seat 31 has an opening of a primary side pressure guiding port 32 communicated with the upstream side in the laminar flow element 23 and a secondary side pressure guiding port 33 communicating with the downstream side of the laminar flow element 23. ing. The pressure of the fluid to be measured 34 flowing on the upstream side in the laminar flow element 23 is transmitted to the primary side pressure guiding port 32. The pressure of the fluid to be measured 34 flowing on the downstream side in the laminar flow element 23 is transmitted to the secondary pressure guiding port 33.

Two metal O-rings 35 and 36 and a spacer 37 are provided between the sensor mounting seat 31 and the pressure sensor 21. The metal O-rings 35 and 36 are composed of pipes made of an annular metal material, and are arranged so as to be concentrically located with respect to the primary side pressure guiding port 32 and the secondary side pressure guiding port 33, respectively. ing. In this embodiment, the metal O-rings 35 and 36 correspond to the "sealing member" in the present invention. The spacer 37 is provided so as to close the gap formed on the outside of the metal O-rings 35 and 36.

The pressure sensor 21 is adhered to a base body 41 that is superposed on the sensor mounting seat 31 via metal O-rings 35 and 36, and to an outer end portion 41a of the base body 41 opposite to the sensor mounting seat 31. It is equipped with a sensor chip 42.
The base body 41 is fastened to the sensor mounting seat 31 by a plurality of mounting bolts 43. The mounting bolt 43 is tightened in a state where the head 43a presses the outer end portion 41a of the base body 41 toward the sensor mounting seat 31.

A primary side pressure receiving chamber 45 in which the barrier diaphragm 44 is a part of the wall is formed at a position corresponding to the primary side pressure guiding port 32 at the inner end portion 41b facing the sensor mounting seat 31 of the base body 41. Has been done. Further, at the inner end portion 41b of the base body 41 facing the sensor mounting seat 31 and at a position corresponding to the secondary side pressure guiding port 33, the barrier diaphragm 46 is a part of the wall to receive the secondary side pressure. A chamber 47 is formed. The two barrier diaphragms 44, 46, the primary side pressure receiving chamber 45, and the secondary side pressure receiving chamber 47 are provided so as to form a pair in the direction in which the primary side pressure guiding port 32 and the secondary side pressure guiding port 33 are lined up, respectively. ing.

The barrier diaphragms 44 and 46 are formed in a disk shape by a metal material, and are fixed to the inner end portion 41b of the base body 41 so that the outer peripheral portion becomes liquid-tight in a state of being exposed toward the sensor mounting seat 31. There is. Therefore, the barrier diaphragms 44 and 46 receive the pressure of the fluid to be measured 34, and partition the inside of the primary side pressure receiving chamber 45 and the inside of the secondary side pressure receiving chamber 47 with respect to the measured fluid 34.

The primary side pressure receiving chamber 45 is connected to a primary side pressure guiding path 51 formed inside the base body 41. The secondary side pressure receiving chamber 47 is connected to the secondary side pressure guiding path 52 formed inside the base body 41. The primary side pressure guiding path 51 and the secondary side pressure guiding path 52 are provided so as to form a pair in the direction in which the primary side pressure guiding port 32 and the secondary side pressure guiding port 33 are lined up, and each of them is a base body. The 41 is formed so as to penetrate from the inner end portion 41b to the outer end portion 41a. Further, the primary side pressure guiding path 51 and the secondary side pressure guiding path 52 are filled with the liquid 53 for pressure transmission. The liquid 53 is also filled in the primary side pressure receiving chamber 45 and the secondary side pressure receiving chamber 47. The base body 41 according to this embodiment is not provided with a sealing hole for injecting the liquid 53 into the primary side pressure guiding path 51 and the secondary side pressure guiding path 52.

One of the barrier diaphragms 44 and 46 provided so as to form a pair, the primary side pressure receiving chamber 45 and the secondary side pressure receiving chamber 47, and the primary side pressure guiding passage 51 and the secondary side pressure guiding passage 52, respectively. The first pressure transmission unit 54 including the barrier diaphragm 44, the primary side pressure receiving chamber 45, and the primary side pressure guiding path 51 is one end (see FIG. 4) of the first passage hole 55 (see FIG. 4) of the sensor chip 42 described later. In FIG. 4, it is connected to the lower end).

Further, the second pressure transmission portion 56 including the other barrier diaphragm 46, the secondary side pressure receiving chamber 47, and the secondary side pressure guiding path 52 is a second passage hole 57 (FIG. 5) of the sensor chip 42 described later. (See) is connected to one end (lower end in FIG. 5).
The outer end portion 41a of the base body 41 is provided with a relay board 58 and a connector 59 for electrically connecting the sensor chip 42 and an external detection circuit (not shown).

The sensor chip 42 is formed in a rectangular shape in a plan view as shown in FIG. 3, and is formed by stacking a plurality of plate-shaped members as shown in FIGS. 4 and 5. In the following, when the thickness direction is shown in explaining each member of the sensor chip 42, the upper side of FIGS. 4 and 5 is referred to as the upper side of the plate-shaped member for convenience.

The sensor chip 42 has a base 61 drawn at the bottom in FIGS. 4 and 5, a flow path member 62 joined to the upper surface of the base 61, and a pressure-sensitive member joined to the upper surface of the flow path member 62. It is composed of a member 63, a lid member 64 joined to the upper surface of the pressure sensitive member 63, and a symmetry adjusting member 65 joined to the upper surface of the lid member 64. The base 61 is made of glass, and the flow path member 62, the pressure sensitive member 63, the lid member 64, and the symmetry adjusting member 65 are each made of silicon. At the center of the sensor chip 42 in the width direction (horizontal direction in FIGS. 3 to 5), a first passage hole 55 and a second passage hole 57 that vertically penetrate the plurality of plate-shaped members described above are provided. Has been drilled.

One end of the first passage hole 55 (on the base 61 side, the lower end in FIG. 4) is connected to the primary side pressure guiding path 51 by adhering the sensor chip 42 to the base body 41. The other end of the first passage hole 55 is closed by the plug member 66 after the liquid 53 for pressure transmission is injected. As the plug member 66, for example, a member that is melted by heat, cooled, and solidified to be fixed to the symmetry adjusting member 65 can be used. By filling the first passage hole 55 with the liquid 53 for pressure transmission, the pressure of the fluid to be measured 34 in the primary side pressure guiding port 32 is transmitted into the sensor chip 42 via the first pressure transmitting portion 54. Will be done.

One end of the second passage hole 57 (on the base 61 side, the lower end in FIG. 5) is connected to the secondary side pressure guiding path 52 by adhering the sensor chip 42 to the base body 41. The other end of the second passage hole 57 is closed by the plug member 67 after the liquid 53 for pressure transmission is injected. The stopper member 67 is the same as the stopper member 66 described above. When the second passage hole 57 is filled with the liquid 53 for pressure transmission, the pressure of the fluid to be measured 34 in the secondary pressure guiding port 33 enters the sensor chip 42 via the second pressure transmitting portion 56. It will be transmitted. In this embodiment, the primary side pressure guiding path 51 and the secondary side pressure guiding path 52, and the first passage hole 55 and the second passage hole 57 correspond to the "pressure guiding path" in the present invention. ..

The sensor chip 42 according to this embodiment has first to fourth functional units.
The first functional unit is a differential pressure measuring unit 71 configured by using the pressure sensitive member 63 and the lid member 64 on the left side of the sensor chip 42 in FIGS. 4 and 5. The differential pressure measuring unit 71 has a first semiconductor diaphragm 72 formed in the pressure sensitive member 63, and a first pressure chamber 73 and a second pressure chamber 74 partitioned by the first semiconductor diaphragm 72. ing. The first semiconductor diaphragm 72 is configured by the bottom of a first recessed portion 75 formed so as to open downward into the pressure sensitive member 63. The first and second passage holes 55 and 57 described above extend in the thickness direction of the first semiconductor diaphragm 72.

In this embodiment, the first semiconductor diaphragm 72 corresponds to the "semiconductor diaphragm" in the present invention. As shown in FIG. 3, a plurality of strain gauges 76 are provided on the upper surface of the first semiconductor diaphragm 72. As the strain gauge 76, for example, a piezo resistance element formed by an impurity diffusion or ion implantation technique can be used. The strain gauge 76 is electrically connected to the relay board 58 by a wiring (not shown).

The first pressure chamber 73 is formed by closing the opening of the first recessed portion 75 by the flow path member 62. The first pressure chamber 73 is connected to the first passage hole 55 via a first communication passage 77 formed of a groove formed in the pressure sensitive member 63, and is used for pressure transmission together with the first passage hole 55. Filled with liquid 53 of.
The second pressure chamber 74 is formed by closing the opening of the second recessed portion 78 formed so as to open downward in the lid member 64 by the pressure sensitive member 63. The second pressure chamber 74 is connected to the second passage hole 57 via a second communication passage 79 formed of a groove formed in the lid member 64, and is connected to the second passage hole 57 together with the second passage hole 57 for pressure transmission. Filled with liquid 53. Therefore, the differential pressure measuring unit 71 measures the differential pressure between the pressure of the fluid to be measured 34 in the primary pressure guiding port 32 and the pressure of the fluid to be measured 34 in the secondary pressure guiding port 33. Can be done.

The second functional unit is an absolute pressure measuring unit 81 configured by using the pressure sensitive member 63 and the lid member 64 on the right side of the sensor chip 42 in FIGS. 4 and 5. The absolute pressure measuring unit 81 has a second semiconductor diaphragm 82 formed in the pressure sensitive member 63, and a first vacuum chamber 83 and a third pressure chamber 84 partitioned by the second semiconductor diaphragm 82. ing. The second semiconductor diaphragm 82 is configured by the bottom of a third recess 85 formed so as to open downward into the pressure sensitive member 63. As shown in FIG. 3, a plurality of strain gauges 86 are provided on the upper surface of the second semiconductor diaphragm 82. These strain gauges 86 are formed in the same manner as the strain gauges 76 provided on the first semiconductor diaphragm 72, and are electrically connected to the relay board 58 via wiring (not shown).

The first vacuum chamber 83 is formed by closing the opening of the third recessed portion 85 by the flow path member 62. The first vacuum chamber 83 is sealed in a vacuum state.
The third pressure chamber 84 is formed by closing the opening of the fourth recessed portion 87 formed so as to open downward in the lid member 64 by the pressure sensitive member 63. The third pressure chamber 84 is connected to the first passage hole 55 via a third communication passage 88 formed of a groove formed in the lid member 64. By filling the third pressure chamber 84 and the third communication passage 88 with the liquid 53 for pressure transmission, the absolute pressure of the fluid to be measured 34 in the primary side pressure guiding port 32 can be measured.

The third functional unit is a dummy diaphragm unit 91 provided above the differential pressure measuring unit 71. The dummy diaphragm portion 91 is composed of a dummy diaphragm 92 formed of the bottom of the second recessed portion 78 and a second vacuum chamber 93 provided in the symmetry adjusting member 65. The second vacuum chamber 93 is formed by closing the opening of the fifth recessed portion 94 formed so as to open downward in the symmetry adjusting member 65 by the lid member 64. The inside of the second vacuum chamber 93 is sealed in a vacuum state.
Since the dummy diaphragm portion 91 is provided in the sensor chip 42, the pressure transmission path including the first passage hole 55 and the pressure transmission path including the second passage hole 57 have a symmetrical structure, so that the differential pressure is differential. And absolute pressure can be measured simultaneously and with high sensitivity.

The fourth functional unit is a liquid amount adjusting unit 95 provided above the absolute pressure measuring unit 81. The liquid amount adjusting unit 95 is composed of a liquid chamber 96 having a predetermined size provided in the symmetry adjusting member 65. The liquid chamber 96 is formed by closing the opening of the sixth recess 97 formed so as to open downward in the symmetry adjusting member 65 by the lid member 64.
The liquid chamber 96 is connected to the second passage hole 57 via a fourth communication passage 98 formed of a groove formed in the symmetry adjusting member 65. The volume of the liquid chamber 96 is equal to the amount of the liquid 53 filled in the pressure transmission path including the first passage hole 55 and the amount of the liquid 53 filled in the pressure transmission path including the second passage hole 57. It is a volume that becomes. By making the amount of the liquid 53 in these two pressure transmission paths the same or making the difference in the amount of the liquid 53 smaller than a predetermined value, the characteristic change due to the expansion / contraction of the liquid 53 due to the temperature change (zero point of the differential pressure). Shift) can be reduced.

The work of injecting the liquid 53 for pressure transmission into the first passage hole 55 and the second passage hole 57 is performed before the plug members 66 and 67 are fixed to the symmetry adjusting member 65. This injection operation is performed by injecting the liquid 53 into the openings 101 and 102 at the upper ends of the first passage hole 55 and the second passage hole 57, respectively. The openings 101 and 102 at the upper ends of the first and second passage holes 55 and 57 correspond to the "injection port" in the present invention. The pressure transfer liquid 53 injected into the openings 101 and 102 of the first and second passage holes 55 and 57 is the primary side pressure passage 51 and the secondary side from the first and second passage holes 55 and 57. It reaches the primary side pressure receiving chamber 45 and the secondary side pressure receiving chamber 47 via the pressure guiding path 52. After the injection operation is completed, the openings 101 and 102 of the first and second passage holes 55 and 57 are closed by the plug members 66 and 67. That is, the openings 101 and 102 are closed by the plug members 66 and 67 with the pressure transmission liquid 53 injected into the first and second pressure transmission portions 54 and 56 and the inside of the sensor chip 42. ..

Therefore, in the pressure sensor 21 according to this embodiment, it is not necessary to provide the base body 41 with a sealing hole for injecting the liquid 53 for pressure transmission, so that the sealing hole is provided. It is possible to suppress a decrease in rigidity of the base body 41. Therefore, it is possible to suppress the deformation of the sensor chip 42 due to the deformation of the base body 41 when the base body 41 is fastened to the sensor mounting seat 31 with the mounting bolt 43. In order to suppress the distortion of the base body 41 in this way, it is not necessary to form the base body 41 to be thick.
Therefore, it is possible to provide a pressure sensor capable of reducing the bolting shift without increasing the size of the base body 41.

In each of the above-described embodiments, an example of applying the present invention to the pressure sensor used in the differential pressure type mass flow controller 22 is shown. However, the present invention is not limited to such a limitation, and can be applied to any pressure sensor as long as it is fastened to the sensor mounting seat with a fastening member.

21 ... Pressure sensor, 31 ... Sensor mounting seat, 32 ... Primary side pressure guiding port, 33 ... Secondary side pressure guiding port, 34 ... Measured fluid, 35, 36 ... Metal O-ring (seal member), 41 ... Base Body 41, 41a ... Outer end, 41b ... Inner end, 42 ... Sensor chip 42, 43 ... Mounting bolt (fastening member), 44, 46 ... Barrier diaphragm, 45 ... Primary side pressure receiving chamber, 47 ... Secondary side Pressure receiving chamber, 51 ... Primary side pressure guiding path, 52 ... Secondary side pressure guiding path, 53 ... Liquid for pressure transmission, 54 ... First pressure transmitting section, 55 ... First passage hole, 56 ... Second Pressure transmission unit, 57 ... second passage hole, 66, 67 ... plug member, 72 ... first semiconductor diaphragm (semiconductor diaphragm), 73 ... first pressure chamber, 74 ... second pressure chamber, 77 ... second 1 communication passage, 79 ... second communication passage, 101, 102 ... opening (injection port).

Claims (2)

A base body that is overlapped with a sealing member and fastened by a fastening member on a sensor mounting seat having a pressure guiding port through which the pressure of the fluid to be measured is transmitted.
A sensor chip having a semiconductor diaphragm and bonded to an outer end portion of the base body opposite to the sensor mounting seat.
A barrier diaphragm provided at the inner end of the base body facing the sensor mounting seat and receiving the pressure of the fluid to be measured is formed so as to be a part of the wall and separated from the fluid to be measured. The pressure receiving chamber and
It is provided with a pressure guiding path formed so as to extend from the pressure receiving chamber to the inside of the sensor chip and filled with a liquid for pressure transmission.
A pressure sensor characterized in that an injection port for injecting the liquid into the pressure guiding path is provided in the sensor chip. In the pressure sensor according to claim 1,
The sensor chip is
A first pressure chamber and a second pressure chamber partitioned by the semiconductor diaphragm,
A first passage hole and a second passage hole extending in the thickness direction of the semiconductor diaphragm,
A first communication passage connecting the first passage hole and the first pressure chamber,
It has a second communication passage that communicates the second passage hole and the second pressure chamber.
The barrier diaphragm, the pressure receiving chamber, and the pressure guiding path are provided so as to form a pair.
A first pressure transmitting portion including one of the barrier diaphragm, the pressure receiving chamber, and the pressure guiding path is connected to one end of the first passage hole.
A second pressure transmitting portion including the other barrier diaphragm, the pressure receiving chamber, and the pressure guiding path is connected to one end of the second passage hole.
The injection port is composed of the other end of the first passage hole and the other end of the second passage hole, and the liquid is supplied to the first and second pressure transmission portions and the sensor chip. A pressure sensor characterized in that it is closed by a plug member while being injected into and inside.

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