Membrane electrode structure and pressure sensor

Abstract

To provide a film electrode structure in which separation of a detection target film can be efficiently confirmed.SOLUTION: The film electrode structure includes: a detection target film; a first electrode part in contact with the lower surface of the detection target film; and a second electrode part in contact with the upper surface of the detection target film, the second electrode part facing the first electrode part across the detection target film at least partially. The first electrode part includes: a first contact region in contact with the detection target film and including a first facing part facing the second electrode part; and a first exposure region exposed from the detection target film.SELECTED DRAWING: Figure 2

Description

Technical Field

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[0001] The present invention relates to a membrane electrode structure and a pressure sensor using the same.

Background Art

[0002] As a sensor such as a pressure sensor, a technique has been proposed in which an insulating film covering directly above the film formation surface, a functional film including electrodes and resistors, and a protective film covering the upper surfaces of the electrodes and resistors are formed on the film formation surface of a metal stem (see Patent Document 1, etc.).

[0003] In such a metal stem on which such a film is formed, for example, between the film formation surface and the film formed thereon, or between the films to be formed, peeling of the film may occur due to the difference in material or linear expansion coefficient. Further, in the manufacturing stage, it is necessary to confirm that no peeling has occurred on the film formed on the film formation surface of the metal stem, and only those without film peeling are sent to the next process.

Prior Art Documents

Patent Documents

[0004]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0005] However, in the conventional membrane electrode structure, since it is confirmed by visual inspection or image analysis that no peeling has occurred on the film, there is a problem that the inspection efficiency and inspection accuracy cannot be improved. Further, when the film is thin and easily transmits light, it is difficult to recognize the film itself by light, and thus such problems tend to become prominent.

[0006] In view of such a situation, the present invention provides a membrane electrode structure capable of efficiently confirming the presence or absence of peeling of a film to be detected, and a pressure sensor using the same.

Means for Solving the Problems

[0007] The membrane electrode structure according to the present invention comprises a film to be detected and A first electrode portion that contacts the lower surface of the film to be detected, It has a second electrode portion that is in contact with the upper surface of the film to be detected and at least a portion of which faces the first electrode portion across the film to be detected, The first electrode portion has a first contact region that is in contact with the film to be detected and includes a first opposing portion that faces the second electrode portion, and a first exposed region that is exposed from the film to be detected.

[0008] The membrane electrode structure according to the present invention has a first electrode portion and a second electrode portion facing each other with the film to be detected in between. By connecting these first and second electrode portions to a delamination detection unit that electrically detects the delamination of the film to be detected between the first and second electrode portions, the presence or absence of delamination of the film to be detected can be easily detected. In particular, since the first electrode portion located on the lower surface of the film to be detected has a first exposed region that is exposed from the film to be detected, electrical connection can also be made to the electrode portion located below the film to be detected.

[0009] Furthermore, for example, the second electrode portion may have a second contact region including a second opposing portion that is in contact with the film to be detected and faces the first electrode portion, and a second exposed region that is exposed from the film to be detected. The first electrode portion may be electrically connected to a peel detection unit that detects the peeling of the film to be detected between the first electrode portion and the second electrode portion via the first exposed region. The second electrode portion may be electrically connected to the peel detection portion via the second exposed region.

[0010] The second electrode portion located on the upper surface of the film to be detected may also have a second exposed region exposed from the film to be detected, similar to the first electrode portion. Such a film electrode structure can be electrically connected to the electrode portions on both the upper and lower surfaces of the film to be detected.

[0011] Furthermore, for example, the first electrode portion may be composed of a conductive film, and the first contact region and the first exposed region may be arranged on the same plane.

[0012] Even in cases where there are other components on the side of the first electrode facing the film to be detected, making it difficult to ensure electrical conductivity from the opposite side, an electrical connection for peel detection can be made from the side facing the film to be detected.

[0013] Furthermore, for example, the film to be detected may include an insulating film that insulates the upper surface from the lower surface.

[0014] Such a film electrode structure can detect the delamination of the insulating film, thereby preventing unexpected decreases in insulation performance due to delamination.

[0015] Furthermore, for example, the film to be detected may include a protective film that covers and protects the member formed on the lower side.

[0016] Such a membrane electrode structure can detect the peeling of the protective film, thereby preventing unexpected decreases in durability due to the peeling of the protective film.

[0017] Furthermore, for example, when viewed from a direction perpendicular to the film to be detected, the area of ​​at least one of the first electrode portion and the second electrode portion may be 1 / 50 or less of the area of ​​the film to be detected.

[0018] By making the area of ​​the first or second electrode portion 1 / 50 or less of the area of ​​the film to be detected, it is easy to secure a region on the underside or top surface of the film to be detected where other functional parts can be placed, while avoiding the electrode portion. Furthermore, because the area that needs to be checked to confirm that there is no delamination is limited, a clearer signal can be obtained when delamination occurs.

[0019] Further, for example, the first electrode portion may have a first electrode first portion and a first electrode second portion that are separated from each other. The second electrode portion may have a second electrode first portion and a second electrode second portion that are separated from each other. At least a part of the second electrode first portion may face the first electrode first portion with the detection film interposed therebetween. At least a part of the second electrode second portion may face the first electrode second portion with the detection film interposed therebetween.

[0020] By each electrode portion having a plurality of separated parts, it is possible to more reliably detect that there is no peeling of the entire detection film.

[0021] Further, for example, the detection film may include an insulating film that insulates the upper surface side and the lower surface side, and a protective film that covers and protects a member formed on the lower surface side. At least a part of the second electrode first portion may face the first electrode first portion with the insulating film interposed therebetween. At least a part of the second electrode second portion may face the first electrode second portion with the protective film interposed therebetween.

[0022] According to such a membrane electrode structure, it is possible to detect the presence or absence of peeling of the insulating film and the protective film by the first portion and the second portion of the electrode portion, respectively.

[0023] Further, for example, the second electrode first portion and the first electrode second portion may be a common electrode.

[0024] By making the second electrode first portion and the first electrode second portion a common electrode, it is possible to detect the presence or absence of peeling of the insulating film and the protective film with a simple electrode structure. [

[0025] Further, for example, at least one of the first electrode portion and the second electrode portion may be applied to the outer edge portion of the detection film.

[0026] Since delamination tends to occur more easily at the outer edge compared to the inner part, this type of film electrode structure allows for more reliable detection of the absence of delamination throughout the entire film being detected.

[0027] Furthermore, for example, the lower surface of the film to be detected is in contact with the first electrode portion and a film-forming surface made of a different material from the first electrode portion, and the adhesion force with the first electrode portion may be smaller than the adhesion force with the film-forming surface.

[0028] With this type of membrane electrode structure, by detecting the absence of delamination between the electrode portion and the film to be detected, it is possible to guarantee that there is no delamination between the film-forming surface and the film to be detected.

[0029] Furthermore, for example, the film to be detected may include an insulating film formed on the film-forming surface of the stainless steel stem. The insulating film may contain at least one of silicon oxide, silicon nitride, and silicon oxynitride.

[0030] This type of membrane electrode structure enables excellent durability even under high temperature and high pressure environments.

[0031] Furthermore, for example, the peel detection unit may detect the capacitance between the first electrode and the second electrode.

[0032] This type of film electrode structure is particularly suitable for detecting delamination when the film to be detected is an insulating film. However, in addition to detecting capacitance, the delamination detection unit can also be used to detect resistance between the first electrode and the second electrode when the film to be detected is conductive or a semiconductor.

[0033] The pressure sensor according to the present invention comprises one of the above-described membrane electrode structures and a deformation detection unit formed on the lower or upper side of the membrane to be detected, which detects the deformation of the membrane due to pressure.

[0034] Such pressure sensors can detect the absence of delamination in the film being detected, thus achieving good reliability.

[0035] Furthermore, for example, the membrane is part of a stainless steel stem, The first electrode portion may be electrically connected to the peel detection portion via the stem.

[0036] In this type of pressure sensor, the electrical connection between the first electrode and the delamination detection unit is ensured by utilizing the conductive material of the stem, which allows for a simpler design of the film shape and wiring structure. [Brief explanation of the drawing]

[0037] [Figure 1] Figure 1 is a schematic cross-sectional view of a pressure sensor according to the first embodiment. [Figure 2] Figure 2 is a top view of the pressure sensor shown in Figure 1, viewed from above. [Figure 3] Figure 3 is a conceptual diagram showing a cross-section of the membrane electrode structure of the pressure sensor shown in Figure 1. [Figure 4] Figure 4 is a conceptual diagram illustrating the peel detection method used by the membrane electrode structure of the pressure sensor shown in Figure 1. [Figure 5] Figure 5 is a conceptual diagram showing the membrane electrode structure of the pressure sensor according to the first modified example. [Figure 6] Figure 6 is a conceptual diagram illustrating the membrane electrode structure of the pressure sensor according to the second embodiment, using a top view and a cross-sectional view. [Figure 7] Figure 7 is a conceptual diagram illustrating the membrane electrode structure of the pressure sensor according to the third embodiment, using a top view and a cross-sectional view. [Figure 8] Figure 8 is a conceptual diagram illustrating the membrane electrode structure of the pressure sensor according to the fourth embodiment, using a top view and a cross-sectional view. [Figure 9] Figure 9 is a conceptual diagram illustrating the membrane electrode structure of the pressure sensor according to the fifth embodiment, using a top view and a cross-sectional view. [Figure 10]Figure 10 is a conceptual diagram illustrating the membrane electrode structure of the pressure sensor according to the sixth embodiment, using a top view and a cross-sectional view. [Figure 11] Figure 11 is a conceptual diagram illustrating the membrane electrode structure of the pressure sensor according to the seventh embodiment, using a top view and a cross-sectional view. [Figure 12] Figure 12 is a conceptual diagram illustrating the membrane electrode structure of the pressure sensor according to the eighth embodiment, using a top view. [Figure 13] Figure 13 is a conceptual diagram illustrating the membrane electrode structure of the pressure sensor according to the ninth embodiment, using a top view. [Figure 14] Figure 14 is a conceptual diagram illustrating the membrane electrode structure of the pressure sensor according to the 10th embodiment, using a top view. [Figure 15] Figure 15 is a schematic cross-sectional view of a pressure sensor according to the 11th embodiment. [Figure 16] Figure 16 is a schematic cross-sectional view of a pressure sensor according to the second modified example. [Figure 17] Figure 17 is a schematic cross-sectional view of a pressure sensor according to a third modified example. [Figure 18] Figure 18 is a graph showing an example of the change in capacitance between electrodes due to the delamination detection unit. [Modes for carrying out the invention]

[0038] The present invention will be described below based on the embodiments shown in the drawings.

[0039] First Embodiment Figure 1 is a schematic cross-sectional view of a pressure sensor 10 using a membrane electrode structure M1 according to a first embodiment of the present invention. As shown in Figure 1, the pressure sensor 10 has a deformation detection unit 30 that detects deformation of the membrane 22 due to pressure, and a membrane electrode structure M1 that can detect peeling of the film to be detected, including an insulating film 50 (see Figure 2). The pressure sensor 10 shown in Figure 1 has a metal stem 20, and the membrane 22 of the metal stem 20 undergoes deformation in response to the pressure received from the inner surface 23 of the membrane 22.

[0040] In this embodiment, the membrane 22 is composed of an end wall formed at one end of a hollow cylindrical metal stem 20. The other end of the metal stem 20 is an open end of the hollow portion, and the hollow portion of the metal stem 20 is in communication with the flow path 12b of the connecting member 12.

[0041] In this embodiment, the membrane electrode structure M1 is described as being used as part of a pressure sensor 10 by being combined with a deformation detection unit 30 (see Figure 2) on top of a membrane 22. However, the membrane electrode structure M1 is not limited to those used in a pressure sensor 10. For example, the membrane electrode structure M1 may also include composite structures of a membrane and electrodes capable of electrically detecting the peeling of the membrane to be detected, and may be used in applications other than the pressure sensor 10, such as strain gauges and other sensors.

[0042] As shown in Figure 1, in the pressure sensor 10, the fluid introduced into the flow path 12b is guided from the hollow portion of the metal stem 20 to the inner surface 23 of the membrane 22, so that the fluid pressure acts on the membrane 22. The metal stem 20 is made of a metal such as stainless steel. Examples of stainless steels that make up the metal stem 20 include austenitic SUS304 and SUS316, and precipitation-hardening SUS630 and SUS631, but are not limited to these.

[0043] A flange portion 21 is formed around the open end of the metal stem 20. The flange portion 21 is formed to protrude radially outward from the peripheral wall of the metal stem 20. The flange portion 21 is sandwiched and fixed between the connecting member 12 and the retaining member 14, thereby sealing the flow path 12b leading to the inner surface 23 of the membrane 22.

[0044] The connecting member 12 has a threaded groove 12a for connecting the pressure sensor 10 to a pipe or external flow path. The pressure sensor 10 is fixed to a pressure chamber containing the fluid to be measured via the threaded groove 12a. As a result, the flow path 12b formed inside the connecting member 12 and the inner surface 23 of the membrane 22 in the metal stem 20 are in airtight communication with the pressure chamber containing the fluid to be measured.

[0045] A circuit board 80 is attached to the upper surface of the retaining member 14. The circuit board 80 has a ring-shaped form that surrounds the metal stem 20, but the shape of the circuit board 80 is not limited to this. Detection signals from the deformation detection unit 30 (see Figure 2) located on the film-forming surface 24 side of the metal stem 20 and from the electrode portion of the film electrode structure M1 are transmitted to the circuit board 80.

[0046] The membrane 22 of the metal stem 20 has a film-forming surface 24. As shown in Figure 1, the film-forming surface 24 of the metal stem 20 is the surface (outer surface) opposite to the inner surface 23 of the membrane 22. Most of the film-forming surface 24 is covered with an insulating film 50, but in this embodiment, as shown in Figure 3, a part of the film-forming surface 24 is exposed from the insulating film 50. The insulating film 50 is the film to be detected, which is the target of peeling detection by the film electrode structure M1. A deformation detection unit 30 (see Figure 2) is formed on the insulating film 50 to detect deformation of the membrane 22 due to pressure.

[0047] The intermediate wiring 82 shown in Figure 1 connects the deformation detection unit 30, which is provided on the film-forming surface 24 side of the membrane 22, to the circuit board 80. The intermediate wiring 82 also connects the first electrode portion (film-forming surface 24 of the metal stem 20) and the second electrode portion 62 of the film electrode structure M1 to the circuit board 80 (see Figure 3). The intermediate wiring 82 shown in Figure 1 is composed of multiple bonding wires, but the intermediate wiring 82 may be a wiring structure other than wire bonding. In the description of the pressure sensor 10, the direction perpendicular to the film-forming surface 24 and toward the inner surface 23 (inside the metal stem 20) is considered downward, and the direction perpendicular to the film-forming surface 24 and toward the opposite side of the inner surface 23 (the direction away from the metal stem 20) is considered upward.

[0048] Figure 2 is a top view of the pressure sensor 10 shown in Figure 1, viewed from above the film-forming surface 24 of the membrane 22. Figure 3 is a cross-sectional view of the pressure sensor 10 shown in Figure 2 along the cross-sectional line A-A'. However, in Figures 2 and 3, the circuit board 80 and intermediate wiring 82 are not shown except in part. As shown in Figures 2 and 3, an insulating film 50 is formed on the film-forming surface 24, which is the upper surface of the membrane 22, and the deformation detection part 30 and the second electrode part 62 are formed on the upper surface 50a of the insulating film 50.

[0049] As shown in Figure 2, the insulating film 50 is formed over a wide area (70% or more, preferably 80% or more) of the film-forming surface 24 on the metal stem 20 shown in Figure 1, and most of the film-forming surface 24 is hidden beneath the insulating film 50. The deformation detection unit 30 includes resistors R1, R2, R3, and R4 connected by electrical wiring 34, and a detection electrode unit 32 which is electrically connected to resistors R1 to R4 and to which the intermediate wiring 82 shown in Figure 1 is connected.

[0050] The resistors R1 to R4 of the deformation detection unit 30 are formed at predetermined positions on the membrane 22, and generate strain in accordance with the deformation of the membrane 22, causing the resistance value to change. These resistors R1 to R4 are connected by electrical wiring 34 to form a Wheatstone bridge circuit. The resistors R1 to R4 of the deformation detection unit 30 are insulated from the film-forming surface 24 of the metal stem 20 by an insulating film 50, which is an insulating film.

[0051] The pressure sensor 10 shown in Figure 1 can detect the fluid pressure acting on the membrane 22 from the output of the deformation detection unit 30 shown in Figure 2. That is, the output of the Wheatstone bridge composed of resistors R1 to R4 is configured to change according to the amount of strain on the membrane 22 due to the fluid pressure. The circuit board 80 shown in Figure 1 can acquire the detection signal from the deformation detection unit 30 via the detection electrode unit 32 and the intermediate wiring 82.

[0052] The pressure sensor 10 shown in Figures 2 and 3 incorporates a membrane electrode structure M1 capable of detecting delamination occurring in the insulating film 50, which is the film to be detected. The membrane electrode structure M1 has an insulating film 50 as the film to be detected, a metal stem 20 as the first electrode portion (particularly the film-forming surface 24 of the membrane 22), and a second electrode portion 62.

[0053] As shown in Figure 3, the film-forming surface 24, which is the first electrode portion of the film electrode structure M1, is in contact with the lower surface 50b of the insulating film 50, which is the film to be detected. As shown in Figure 2, the film-forming surface 24 is approximately circular when viewed from above and has a larger area than the insulating film 50.

[0054] Furthermore, as shown in Figure 3, the second electrode portion 62 of the film electrode structure M1 is positioned on the upper surface 50a of the insulating film 50, which is the film to be detected, and does not overlap with the deformation detection portion 30. The lower surface of the second electrode portion 62 is in contact with the upper surface 50a of the insulating film 50, and at least a portion of it faces the film-forming surface 24, which is the first electrode portion, across the insulating film 50. The second electrode portion 62 is made of a conductive film, such as a thin film of metal. For example, the material of the second electrode portion 62 can be the same as the material of the detection electrode portion 32 in the deformation detection portion 30 shown in Figure 2, but the material of the second electrode portion 62 may be different from that of the detection electrode portion 32.

[0055] As shown in Figures 2 and 3, the film-forming surface 24 of the metal stem 20, which functions as the first electrode portion, has a first contact region 24a that contacts the insulating film 50, which is the film to be detected, and a first exposed region 24b that is exposed from the insulating film 50. The first contact region 24a includes a first opposing portion 24aa that faces the second electrode portion 62.

[0056] A connection portion 64 to which the intermediate wiring 82 is connected is formed in the first exposed region 24b. The metal stem 20, including the film-forming surface 24 of the membrane 22, is made of a conductive material, and the first opposing portion 24aa of the film-forming surface 24, which serves as the first electrode portion, is electrically connected to the circuit board 80 (see Figure 1) via the other portion of the first contact region 24a, the first exposed region 24b, and the intermediate wiring 82, etc. Also, as shown in Figure 3, both the first contact region 24a and the first exposed region 24b are parts of the film-forming surface 24 and are located on the same plane.

[0057] As shown in Figures 2 and 3, the second electrode portion 62 of the membrane electrode structure M1 has a second contact region 62a that contacts the insulating film 50 and a second exposed region 62b that is exposed from the insulating film 50. The second contact region 62a is the entire lower surface of the second electrode portion 62, and the second exposed region 62b is the entire upper surface of the second electrode portion 62. The second contact region 62a also includes a second opposing portion that faces the film-forming surface 24. However, since the entire second contact region 62a faces the film-forming surface 24 of the membrane 22, which is the first electrode portion, the entire second contact region 62a constitutes the second opposing portion.

[0058] As shown in Figure 3, the second exposed region 62b is connected to the intermediate wiring 82, similar to the first exposed region 24b. Since the second electrode portion 62 is a conductive film, the second opposing portion of the second electrode portion 62 (the entire second contact region 62a) is electrically connected to the circuit board 80 (see Figure 1) via the second exposed region 62b and the intermediate wiring 82, etc.

[0059] Figure 4 is a schematic diagram showing the mechanism of delamination detection by the film electrode structure M1 of the pressure sensor 10. Figure 4(a) shows a state in which no delamination has occurred in the insulating film 50, which is the film to be detected, and Figure 4(b) shows a state in which delamination has occurred in a part of the insulating film 50, which is the film to be detected.

[0060] The insulating film 50 shown in Figure 4(a) is an insulating film that insulates the upper surface 50a side from the lower surface 50b side of the insulating film 50. The material of the insulating film 50 is not particularly limited, but for example, it can be a silicon-based film, and it is preferable from the viewpoint of durability under high temperature and high pressure that the film contains at least one of silicon oxide, silicon nitride, and silicon oxynitride.

[0061] As shown in Figure 4(a), the film-forming surface 24, which serves as the first electrode portion, and the second electrode portion 62, which face each other across the insulating film 50, are electrically connected to the delamination detection unit 70. The delamination detection unit 70 may, for example, detect the capacitance between the film-forming surface 24 and the second electrode portion 62. The delamination detection unit 70 may be provided in the circuit board 80 shown in Figure 1, the control unit of the pressure sensor 10 connected via the circuit board 80, or the inspection unit of the metal stem 20 during manufacturing, but the installation location of the delamination detection unit 70 is not particularly limited.

[0062] As shown in Figure 4(b), when delamination occurs between the film-forming surface 24 and the insulating film 50, particularly between the first opposing portion 24aa of the first contact region 24a and the insulating film 50, the capacitance detected by the delamination detection unit 70 changes. Figure 18 is a graph showing the relationship between the amount of delamination between the first opposing portion 24aa and the insulating film 50 (horizontal axis) and the capacitance detected by the delamination detection unit 70 (vertical axis).

[0063] As shown in Figure 18, when the amount of delamination between the insulating film 50 and the first opposing portion 24aa increases, the capacitance detected by the delamination detection unit 70 decreases. Therefore, by detecting the change in capacitance, the delamination detection unit 70 can detect delamination between the insulating film 50 and the film-forming surface 24 as shown in Figure 4(b). Figure 18 is an example of the film electrode structure M1 shown in Figure 4, in which an insulating film 50 containing silicon oxide and with a thickness of 1 μm is formed on the film-forming surface 24 of a stainless steel metal stem 20, and a conductive film containing Au is formed on the upper surface 50a of the insulating film 50 to form the second electrode portion 62.

[0064] As shown in Figures 4(a) and 4(b), the film electrode structure M1 is capable of detecting delamination of the insulating film 50 between the film-forming surface 24, which serves as the first electrode portion, and the second electrode portion 62. The delamination detection unit 70 of the film electrode structure M1 detects not only delamination occurring between the first contact region 24a of the film-forming surface 24 and the insulating film 50, but also delamination occurring between the second contact region 62a of the second electrode portion 62 and the insulating film 50. When the delamination detection unit 70 detects capacitance, it detects delamination of the insulating film 50 in the portions where the film-forming surface 24 and the second electrode portion 62 face each other (first opposing portion 24aa and second opposing portion). Therefore, it is preferable that the second electrode portion 62 be formed in a position where the insulating film 50 is easily delaminated from the film-forming surface 24 (for example, near the outer edge of the insulating film 50) and so as to face the film-forming surface 24 at that position.

[0065] The insulating film 50 shown in Figures 1 to 4 can be formed on the film-forming surface 24, which is the outer surface of the membrane 22, by a vapor deposition method such as CVD. The thickness of the insulating film 50 is preferably 10 μm or less, and more preferably 1 to 5 μm.

[0066] The material of the second electrode portion 62 is not particularly limited, but examples include a conductive thin film containing Au, Al, Ni, or platinum group elements. The second electrode portion 62 can be formed by thin-film methods such as sputtering or vapor deposition, but the method of forming the second electrode portion 62 is not particularly limited. The thickness of the second electrode portion 62 is preferably 1 μm or less, and more preferably 0.1 to 0.5 μm.

[0067] The deformation detection unit 30 shown in Figure 2 can be manufactured by forming a strain resistance film and an electrode film in a predetermined shape on the upper surface 50a of the insulating film 50. Examples of strain resistance films that become resistors R1 to R4 and part of the electrical wiring 34 include conductive thin films containing Cr or Ar, but are not particularly limited. The resistors R1 to R4 of the deformation detection unit 30 are manufactured, for example, by patterning a strain resistance film formed by a thin-film method into a predetermined shape. The detection electrode unit 32 is also composed of a thin film, similar to the strain resistance film, and examples of materials for the detection electrode unit 32 include metals such as Au, Al, and Ni.

[0068] As described above, the pressure sensor 10 according to the first embodiment, as shown in Figures 1 to 4, is formed on the upper surface 50a side of the insulating film 50 and has a deformation detection unit 30 that detects deformation of the membrane 22 due to pressure. The pressure sensor 10 also has a film electrode structure M1 that can detect delamination of the insulating film 50. Therefore, the pressure sensor 10 can detect that no delamination has occurred between the insulating film 50 and the film-forming surface 24 using the film electrode structure M1, and then detect pressure using the deformation detection unit 30, thereby improving the accuracy of the detected value and preventing the detection of erroneous values ​​due to delamination.

[0069] Furthermore, the membrane electrode structure M1 detects delamination of the film being detected from changes in electrical detection values ​​such as changes in capacitance, thus efficiently confirming that no delamination has occurred in the film being detected. In addition, the membrane electrode structure M1 can improve inspection efficiency and accuracy compared to conventional methods such as visual inspection and image analysis. Moreover, because it is an electrical detection method, it can be relatively easily incorporated into a pressure sensor 10 as a product.

[0070] Furthermore, as shown in Figure 3, the film-forming surface 24 of the membrane 22, which serves as the first electrode portion located on the lower surface 50b of the insulating film 50, has a first exposed region 24b that is exposed from the insulating film 50, thereby enabling electrical connection to the electrode portion located beneath the insulating film 50.

[0071] Furthermore, if the stem 20 is made of stainless steel or a similar material with good conductivity, the entire metal stem 20, not just the film-forming surface 24 of the membrane 22, can be considered as the first electrode portion. In this case, the wiring structure connecting the peel detection unit 70 and the first electrode portion shown in Figure 4 is not limited to a structure that forms a first exposed region 24b on the film-forming surface 24 of the membrane 22. Figure 5 is a cross-sectional view of a pressure sensor 110 having a membrane electrode structure M12 according to the first modified example.

[0072] In the membrane electrode structure M12 of the pressure sensor 110 shown in Figure 5, the entire metal stem 20 constitutes the first electrode portion. The pressure sensor 110 and membrane electrode structure M12 differ from the pressure sensor 10 and membrane electrode structure M1 of the first embodiment in that the insulating film 150 covers the entire film-forming surface 24 of the membrane 22, and the first exposed region of the first electrode portion is the outer surface 26 of the stem. However, in other respects, they are the same as the pressure sensor 10 and membrane electrode structure M11. In describing the pressure sensor 110 and membrane electrode structure M12 shown in Figure 5, the differences from the pressure sensor 10 shown in Figure 3, etc., will be the focus, and commonalities with the pressure sensor 10 will be given the same reference numerals and their descriptions will be omitted.

[0073] As shown in Figure 5, in the film electrode structure M12, the lower surface 150b of the insulating film 150 is in contact with the entire film-forming surface 24, and the entire film-forming surface 24 corresponds to the first contact region of the first electrode portion. Such an insulating film 150 allows for a larger area of ​​the upper surface 150a on which the deformation detection unit 30 is placed compared to the insulating film 50 shown in Figures 2 and 3, and is easy to manufacture as it only requires forming the insulating film 150 over the entire film-forming surface 24.

[0074] The film electrode structure M12, like the film electrode structure M1 shown in Figure 3, has a second electrode portion 62 formed on the upper surface 150a of the insulating film 150. In addition, a first opposing portion 24aa is formed on the film forming surface 24 corresponding to the first contact region, in the portion of the second electrode portion 62 facing the second contact region 62a. Note that the second electrode portion 62 shown in Figure 5 is the same as the second electrode portion 62 shown in Figure 3, where the entire second contact region 62a is the second opposing portion, and the upper surface of the second electrode portion 62 is the second exposed region 62b.

[0075] As shown in Figure 5, in the film electrode structure M12, the entire metal stem 20 is the first electrode portion, and the outer surface 26 of the stem that is exposed from the insulating film 150 constitutes the first exposed region of the first electrode portion. The outer surface 26 of the stem is provided with a connection portion 164 to which the intermediate wiring 182 is connected, and the intermediate wiring 182 that electrically connects the delamination detection unit 70 (see Figure 4) and the first electrode portion is connected to the connection portion 164. As a result, the film electrode structure M12 can detect delamination occurring between the insulating film 150 and the film-forming surface 24 from changes in capacitance, similar to the film electrode structure M1 shown in Figure 4.

[0076] Furthermore, the pressure sensor 110 and membrane electrode structure M12 according to the first modified example have similarities with the pressure sensor 10 and membrane electrode structure M1, and provide the same effects as the pressure sensor 10 and membrane electrode structure M1.

[0077] Second Embodiment Figure 6 is a conceptual diagram illustrating the membrane electrode structure M2 of the pressure sensor 210 according to the second embodiment, using a top view (Figure 6(a)) and a cross-sectional view (Figure 6(b)). The membrane electrode structure M2 differs from the membrane electrode structure M1 of the pressure sensor 10 shown in Figure 3 in that it has a first electrode portion 261 provided on the film-forming surface 24 separately from the metal stem 20. However, the pressure sensor 210 and the membrane electrode structure M2 are similar to the pressure sensor 10 and membrane electrode structure M1 of the first embodiment shown in Figure 3, etc., except that the shape of the first electrode portion 261 and the insulating film 250 are different. In describing the membrane electrode structure M2 of the pressure sensor 210 according to the second embodiment, the differences from the pressure sensor 10 and membrane electrode structure M1 of the first embodiment will be explained, and the common points with the pressure sensor 10 and membrane electrode structure M1 will not be explained.

[0078] As shown in Figure 6, an insulating film 250 and a first electrode portion 261 are formed on the film-forming surface 24 of the metal stem 20 of the pressure sensor 210. Furthermore, the insulating film 250 is formed so that a portion of it overlaps the first electrode portion 261. Therefore, the lower surface 250b of the insulating film 250 has a portion that contacts the film-forming surface 24 of the metal stem 20 and the membrane 22, and a portion that contacts the upper surface of the first electrode portion 261 (particularly the first contact region 261a of the first electrode portion 261).

[0079] The first electrode portion 261 is composed of a conductive film, similar to the second electrode portion 62. The first electrode portion 261 can be formed in a predetermined area of ​​the film formation surface 24 by thin-film methods such as sputtering or vapor deposition. The material of the first electrode portion 261 is not particularly limited as long as it is a conductive material, but it is preferable that it be a different material from the film formation surface 24, as described below.

[0080] In other words, by making the material of the first electrode portion 261 different from that of the film-forming surface 24, the adhesion force between the lower surface 250b of the insulating film 250 and the first electrode portion 261 can be made smaller than the adhesion force between the lower surface 250b of the insulating film 250 and the film-forming surface 24. For example, if the material of the metal stem 20 including the membrane 22 is stainless steel, the adhesion force between the lower surface 250b and the first electrode portion 261 can be adjusted to a desired size by constructing the first electrode portion 261 with a thin film containing transition elements belonging to the 5th and 6th periods (specifically, Y, Zr, Nb, Mo, Tc, Ru, Rh, Pd, Ag, La, Ce, Pr, Nd, PM, SM, Eu, Gd, Tb, Dy, Ho, Er, TM, Yb, Lu, Hf, Ta, W, Re, Os, Ir, Pt) or platinum group elements (specifically, Ru, Rh, Pd, Os, Ir, Pt).

[0081] By making the adhesion force between the lower surface 250b of the insulating film 250 and the first electrode portion 261 smaller than the adhesion force between the lower surface 250b of the insulating film 250 and the film-forming surface 24, the absence of delamination can be detected by the film electrode structure M2, thereby suitably guaranteeing that there is no delamination between the insulating film 250, which has a greater adhesion force, and the film-forming surface 24.

[0082] As shown in Figures 6(a) and 6(b), the upper surface of the first electrode portion 261 has a first contact region 261a that contacts the lower surface 250b of the insulating film 250, and a first exposed region 261b that is exposed from the insulating film 250. The first contact region 261a and the first exposed region 261b are located on the same plane and are connected below the outer edge of the insulating film 250.

[0083] Furthermore, the first contact region 261a has a first opposing portion 261aa that faces the lower surface of the second electrode portion 62 across the insulating film 250. The second electrode portion 62 is provided on the upper surface 250a of the insulating film 250. The second contact region 62a, which is the lower surface of the second electrode portion 62, is in contact with the upper surface 250a of the insulating film 250, and at least a part of the second contact region 62a faces the first electrode portion 261 across the insulating film 250. That is, the first opposing portion 261aa formed on the upper surface of the first electrode portion 261 and the second opposing portion (the entirety of the second contact region 62a) formed on the lower surface of the second electrode portion 62 face each other.

[0084] In the film electrode structure M2 shown in Figure 6, the area of ​​the second contact region 62a of the second electrode portion 62 and the area of ​​the first contact region 261a of the first electrode portion 261 are approximately the same. However, the shape and size of the second contact region 62a and the first contact region 261a are not limited to the example shown in Figure 6, and one may have a larger area than the other.

[0085] Intermediate wiring 82 is connected to the first exposed region 261b of the first electrode portion 261 and the second exposed region 62b, which is the upper surface of the second electrode portion 62. As a result, the first electrode portion 261 and the second electrode portion 62 of the film electrode structure M2 are electrically connected to the peel detection unit 70 (see Figure 4), similar to the film electrode structure M1 shown in Figure 4.

[0086] The film electrode structure M2 shown in Figure 6, similar to the film electrode structure M1 described using Figures 4 and 18, can detect delamination occurring in the insulating film 250 between the first electrode portion 261 and the second electrode portion 62 by detecting a change in capacitance between the first electrode portion 261 and the second electrode portion 62. Furthermore, the film electrode structure M2 can suitably guarantee that there is no delamination between the insulating film 250 and the film-forming surface 24 by using the first electrode portion 261, whose adhesion force to the insulating film 250 is smaller than that of the film-forming surface 24 of the metal stem 20.

[0087] Furthermore, the pressure sensor 210 and membrane electrode structure M2 according to the second embodiment have the same effects as the pressure sensor 10 and membrane electrode structure M1 in terms of their common parts.

[0088] Third Embodiment Figure 7 is a conceptual diagram illustrating the membrane electrode structure M3 of the pressure sensor 310 according to the third embodiment, using a top view (Figure 7(a)) and a cross-sectional view (Figure 7(b)). The membrane electrode structure M3 differs from the membrane electrode structure M1 of the pressure sensor 10 shown in Figures 2 and 3 in that the detection electrode portion 332, which is one of the detection electrode portions 32 and 332 of the deformation detection unit 30, and the strain resistance film 334 beneath it also serve as the second electrode portion 362 of the membrane electrode structure M3. However, the pressure sensor 310 and membrane electrode structure M3 are similar to the pressure sensor 10 and membrane electrode structure M1 of the first embodiment shown in Figures 2 and 3, etc., except that the detection electrode portion 332 and the strain resistance film 334 also serve as the second electrode portion 362. In describing the pressure sensor 310 and membrane electrode structure M3 according to the third embodiment, the differences from the pressure sensor 10 and membrane electrode structure M1 of the first embodiment will be explained, and the commonalities with the pressure sensor 10 and membrane electrode structure M1 will not be explained.

[0089] The membrane electrode structure M3 shown in Figure 7, like the membrane electrode structures M1 shown in Figures 2 and 3, is capable of detecting the delamination between the insulating film 50 formed on the film-forming surface 24 of the membrane 22 and the film-forming surface 24, which also serves as the first electrode portion. The film-forming surface 24, which functions as the first electrode portion of the membrane electrode structure M1, has a first contact region 24a that contacts the lower surface 50b of the insulating film 50 and a first exposed region 24b that is exposed from the insulating film 50. The first contact region 24a includes a first opposing portion 324aa that faces the strain-resistant film 334, which functions as the second electrode portion, across the insulating film 40.

[0090] As shown in Figures 7(a) and 7(b), the second electrode portion 362 in the film electrode structure M3 is composed of a detection electrode portion 332, which is part of the deformation detection portion 30, and a strain resistance film 334, and has a two-layer structure. The strain resistance film 334 constitutes the lower layer portion of the second electrode portion 362 and is in contact with the upper surface 50a of the insulating film 50. The strain resistance film 334 is made of the same material as the resistors R1 to R4 and electrical wiring 34 of the deformation detection portion 30, and is formed on the upper surface 50a of the insulating film 50 using the same thin-film formation process as the resistors R1 to R4 and electrical wiring 34.

[0091] The detection electrode portion 332 constitutes the upper layer of the second electrode portion 362 in the membrane electrode structure M3 and is formed on the upper surface of the strain-resistant film 334. A film similar to the strain-resistant film 334 is also formed on the lower surface of the other detection electrode portions 32 in the deformation detection portion 30, in addition to the detection electrode portion 332.

[0092] As shown in Figure 7(b), in the second electrode section 362, which has a two-layer structure consisting of a detection electrode section 332 and a strain-resistance film 334, the lower surface of the strain-resistance film 334 forms a second contact region where it contacts the insulating film 50. In addition, the entire lower surface of the strain-resistance film 334 faces the film-forming surface 24 which serves as the first electrode section, and forms a second facing region.

[0093] Furthermore, in the second electrode portion 362, the upper surface of the upper detection electrode portion 332 constitutes a second exposed region that is exposed from the insulating film 50, which is the film to be detected. An intermediate wiring 82 is connected to the connection portion 64 provided in the first exposed region 24b and to the detection electrode portion 332 that constitutes the second exposed region. As a result, the film-forming surface 24 as the first electrode portion and the second electrode portion 362 are electrically connected to the peel detection portion 70 (see Figure 4) via the intermediate wiring 82, etc., similar to the film electrode structure M1 shown in Figure 4.

[0094] In this way, the film electrode structure M3 can detect delamination occurring between the film-forming surface 24 (particularly the first opposing portion 324aa) and the insulating film 50 by detecting a change in capacitance between the film-forming surface 24, which serves as the first electrode portion, and the second electrode portion 362. Furthermore, the film electrode structure M3 can also detect delamination occurring between the insulating film 50 and the strain-resistive film 334 by detecting a change in capacitance using the delamination detection unit 70.

[0095] In the membrane electrode structure M3, the film-forming surface 24 also serves as the first electrode portion, and the detection electrode portion 332, which is part of the deformation detection portion 30, and the strain resistance film 334 also serve as the second electrode portion. Therefore, it can be easily manufactured by adding only a few processes to a conventional pressure sensor that does not have the membrane electrode structure M3. Furthermore, because the membrane electrode structure M3 requires fewer additional structures compared to a conventional pressure sensor that does not have the membrane electrode structure M3, it can be incorporated into the small space of the pressure sensor 310, which is advantageous from the standpoint of miniaturization.

[0096] Furthermore, the pressure sensor 310 and membrane electrode structure M3 according to the third embodiment provide the same effects as the pressure sensor 10 and membrane electrode structure M1 in terms of their common parts.

[0097] Fourth Embodiment Figure 8 is a conceptual diagram illustrating the membrane electrode structure M4 of the pressure sensor 410 according to the fourth embodiment, using a top view (Figure 8(a)) and a cross-sectional view (Figure 8(b)). In the membrane electrode structure M4, the detected film is a protective film 490 instead of an insulating film 450, and the arrangement and shape of the first electrode portion 461 and the second electrode portion 462 differ from the membrane electrode structure M1 of the pressure sensor 10 shown in Figures 2 and 3. However, the pressure sensor 410 and membrane electrode structure M4 are similar to the pressure sensor 10 and membrane electrode structure M1 of the first embodiment shown in Figures 2 and 3 in that they have a metal stem 20 and a deformation detection portion 30. In describing the pressure sensor 410 and membrane electrode structure M4 according to the fourth embodiment, the differences from the pressure sensor 10 and membrane electrode structure M1 of the first embodiment will be explained, and common points with the pressure sensor 10 and membrane electrode structure M1 will be denoted by the same reference numerals and their explanation will be omitted.

[0098] As shown in Figures 8(a) and 8(b), the pressure sensor 410, like the pressure sensor 10 shown in Figures 2 and 3, has a metal stem 20 with a membrane 22 and a deformation detection unit 30 for detecting deformation of the membrane 22. An insulating film 450 is formed on the film-forming surface 24 of the membrane 22, insulating the film-forming surface 24 from the deformation detection unit 30. The insulating film 450 differs in shape from the insulating film 50 shown in Figures 2 and 3 in that it covers the entire film-forming surface 24, but in aspects other than shape, such as material and formation method, it is the same as the insulating film 50.

[0099] The pressure sensor 410 has a protective film 490. The protective film 490 covers and protects components such as resistors R1 to R4 of the deformation detection unit 30, which are formed on the lower surface 490b of the protective film 490. The material of the protective film 490 may be, for example, an insulating thin film containing silicon oxide, but the material of the protective film 490 is not particularly limited as long as it protects resistors R1 to R4, which are formed from strain resistance films or the like.

[0100] The film electrode structure M4 detects the peeling of the protective film 490. The film electrode structure M4 has a first electrode portion 461 that contacts the lower surface 490b of the protective film 490, and a second electrode portion 462 that contacts the upper surface 490a of the protective film 490 and faces the first electrode portion 461 across the protective film 490. The first electrode portion 461 and the second electrode portion 462 are composed of a conductive film similar to the detection electrode portion 32 and the second electrode portion 62 shown in Figure 3. The first electrode portion 461 and the second electrode portion 462 are formed on the upper surface of the insulating film 450 and the protective film 490 by a thin film formation process such as sputtering or CVD.

[0101] As shown in Figure 8(b), the first electrode portion 461 is formed on the upper surface 450a of the insulating film 450, and the lower surface of the first electrode portion 461 is in contact with the upper surface 450a of the insulating film 450. The upper surface of the first electrode portion 461 has a first contact region 461a that contacts the protective film 490 and a first exposed region 461b that is exposed from the protective film 490. The first contact region 461a and the first exposed region 461b are located on the same plane and are connected below the outer edge of the protective film 490.

[0102] The first contact area 461a includes a first opposing portion that faces the second electrode portion 462 across the protective film 490. Although not shown in Figure 8(b), an intermediate wiring 82 that electrically connects the peel detection unit 70 and the first electrode portion 461 is connected to the first exposed area 461b (see Figure 4).

[0103] The second electrode portion 462 is formed on the upper surface 490a of the protective film 490. The entire lower surface of the second electrode portion 462 is a second contact region 462a that contacts the protective film 490, and the upper surface of the second electrode portion 462 is a second exposed region 462b that is exposed from the protective film 490. Furthermore, the second contact region 462a, which is the lower surface of the second electrode portion 462, faces the upper surface of the first electrode portion 461 across the protective film 490, and the entire area is also a second facing region.

[0104] Furthermore, although not shown in Figure 8(b), an intermediate wiring 82 is connected to the second exposed region 462b, electrically connecting the peel detection unit 70 and the second electrode unit 462 (see Figure 4). This film electrode structure M4 detects the peeling of the protective film 490 between the first electrode unit 461 and the second electrode unit 462 by detecting a change in capacitance between the first electrode unit 461 and the second electrode unit 462, similar to the film electrode structure M1 shown in Figure 4.

[0105] For example, the film electrode structure M4 can detect delamination occurring on the lower surface 490b of the protective film 490, such as delamination between the first electrode portion 461 and the protective film 490. On the other hand, the lower surface 490b of the protective film 490 is also in contact with strain resistance films such as resistors R1 and R2, the detection electrode portion 32, and the upper surface of the insulating film 450. Therefore, by making the adhesion force between the protective film 490 and the first electrode portion 461 in the film electrode structure M4 smaller than the adhesion force of the protective film 490 to the strain resistance film and the detection electrode portion 32, the film electrode structure M4 can detect the absence of delamination and suitably guarantee that there is no delamination between the protective film 490 and the strain resistance film, etc., where the adhesion force is greater.

[0106] In the pressure sensor 410, the deformation detection unit 30 is positioned on the lower side of the protective film 490, which is the film to be detected in the film electrode structure M4. However, as in the pressure sensor 10, the deformation detection unit 30 may be positioned on the upper side of the insulating film 50, which is the film to be detected in the film electrode structure M1. How the film electrode structures M1 and M4 are incorporated into the pressure sensors 10 and 410 can be changed according to the application of the pressure sensors 10 and 40. Furthermore, the pressure sensor 410 and film electrode structure M4 according to the fourth embodiment have the same effects as the pressure sensor 10 and film electrode structure M1 in terms of their common parts.

[0107] Fifth Embodiment Figure 9 is a conceptual diagram illustrating the membrane electrode structure M5 of the pressure sensor 510 according to the fifth embodiment, using a top view (Figure 9(a)) and a cross-sectional view (Figure 9(b)). The membrane electrode structure M5 differs from the membrane electrode structure M4 of the pressure sensor 410 shown in Figure 8 in that the detected film includes an insulating film 250 and a protective film 490, and the first electrode portion 541 and the second electrode portion 542 each include a first portion and a second portion. However, the pressure sensor 510 and membrane electrode structure M5 are similar to the pressure sensor 410 and membrane electrode structure M4 of the fourth embodiment shown in Figure 8 in that they have a metal stem 20, a deformation detection portion 30, and a protective film 490. In describing the pressure sensor 510 and membrane electrode structure M5 according to the fifth embodiment, the differences from the pressure sensor 410 and membrane electrode structure M4 of the fifth embodiment will be explained, and common parts with the pressure sensor 410 and membrane electrode structure M4 will be denoted by the same reference numerals and their explanation will be omitted.

[0108] As shown in Figures 9(a) and 9(b), the membrane electrode structure M5 incorporated into the pressure sensor 510 includes an insulating film 250 and a protective film 490 as the film to be detected. The first electrode portion 541 of the membrane electrode structure M5 has a first electrode first portion 561 and a first electrode second portion 566 that are separated from each other. The second electrode portion 542 of the membrane electrode structure M5 has a second electrode first portion 562 and a second electrode second portion 567 that are separated from each other.

[0109] As shown in Figure 9(b), at least a portion of the second electrode's first portion 562 faces the first electrode's first portion 561 across the insulating film 250, and the peeling of the insulating film 250 is detected by these second electrode's first portion 562 and first electrode's first portion 561. In other words, the first electrode's first portion 561, the second electrode's first portion 562, and the insulating film 250 of the film electrode structure M5 have the same structure as the first electrode portion 261, the second electrode portion 62, and the insulating film 250 of the film electrode structure M2 shown in Figure 6.

[0110] Furthermore, at least a portion of the second electrode second portion 567 faces the first electrode second portion 566 across the protective film 490, and the peeling of the protective film 490 is detected by these second electrode second portion 567 and first electrode second portion 566. In other words, the first electrode second portion 566, the second electrode second portion 567 and the protective film 490 of the membrane electrode structure M5 have the same structure as the first electrode portion 461, the second electrode portion 462 and the protective film 490 of the membrane electrode structure M4 shown in Figure 8.

[0111] The delamination detection unit 70 (see Figure 3) of the film electrode structure M5 can detect delamination occurring in the insulating film 250 and the protective film 490 from the detection signals from the first electrode section 541 and the second electrode section 542, similar to the film electrode structure M2 shown in Figure 6 and the film electrode structure M4 shown in Figure 8. Furthermore, the delamination detection unit 70 (see Figure 3) of the film electrode structure M5 can separately and independently detect the delamination of the insulating film 250 by the first sections 561 and 562 and the delamination of the protective film 490 by the second sections 566 and 567. However, the film electrode structure M5 may also detect the delamination occurring in the insulating film 250 and the protective film 490 together.

[0112] Furthermore, the pressure sensor 510 and membrane electrode structure M5 according to the fifth embodiment have the same effects as the pressure sensor 410 and membrane electrode structure M4 in terms of the parts common to them.

[0113] Sixth Embodiment Figure 10 is a conceptual diagram illustrating the membrane electrode structure M6 of the pressure sensor 610 according to the sixth embodiment, using a top view (Figure 10(a)) and a cross-sectional view (Figure 10(b)). The membrane electrode structure M6 differs from the membrane electrode structure M5 of the pressure sensor 510 shown in Figure 9 in that the first portion of the first electrode is composed of a film-forming surface 24, and the first portion of the second electrode 662 is composed of a detection electrode portion 332 and a strain-resistance film 334. However, the pressure sensor 610 and membrane electrode structure M6 are similar to the pressure sensor 510 and membrane electrode structure M5 of the fifth embodiment shown in Figure 9, except that the configuration of the first portions 24 and 662 that detect the peeling of the insulating film 50 is different. In describing the pressure sensor 610 and membrane electrode structure M6 according to the sixth embodiment, the differences from the pressure sensor 510 and membrane electrode structure M5 of the fifth embodiment will be explained, and commonalities with the pressure sensor 510 and membrane electrode structure M5 will be denoted by the same reference numerals and their explanation will be omitted.

[0114] As shown in Figures 10(a) and 10(b), the membrane electrode structure M6 incorporated into the pressure sensor 610 includes an insulating film 50 and a protective film 490 as the film to be detected, similar to the membrane electrode structure M5 shown in Figure 9. The first electrode portion 641 of the membrane electrode structure M6 has a film-forming surface 24 (part of the metal stem 20) as the first part of the first electrode and a second part 566 of the first electrode. The second electrode portion 642 of the membrane electrode structure M6 has a first part 662 of the second electrode and a second part 567 of the second electrode.

[0115] As shown in Figure 10(b), in the film electrode structure M6, the film-forming surface 24 of the metal stem 20 constitutes the first part of the first electrode. The detection electrode portion 332 and strain resistance film 334 of the deformation detection unit 30 constitute the first part 662 of the second electrode. Thus, in the film electrode structure M6, the delamination of the insulating film 50 is detected by the film-forming surface 24 and the first part 662 of the second electrode. In other words, the film-forming surface 24, the first part 662 of the second electrode and the insulating film 50, which function as the first part of the first electrode in the film electrode structure M6, have the same structure as the film-forming surface 24, the second electrode portion 362 and the insulating film 50 in the film electrode structure M3 shown in Figure 7.

[0116] Furthermore, the second portion 566 of the first electrode, the second portion 567 of the second electrode, and the protective film 490 of the membrane electrode structure M6 have the same structure as the second portion 566 of the first electrode, the second portion 567 of the second electrode, and the protective film 490 of the membrane electrode structure M5 shown in Figure 9.

[0117] The delamination detection unit 70 (see Figure 4) of the film electrode structure M6 can also detect delamination occurring in the insulating film 50 and the protective film 490, similar to the film electrode structure M5 shown in Figure 9. In the film electrode structure M6, the second portion 566 of the first electrode faces the film-forming surface 24, which is the first portion of the first electrode, and may therefore also serve as the first portion of the second electrode for detecting the delamination of the insulating film 50. By using the first portion of the second electrode and the second portion 566 of the first electrode as a common electrode, the delamination of the insulating film 50 and the protective film 490 can be detected with a simple structure.

[0118] Furthermore, the pressure sensor 610 and membrane electrode structure M6 according to the sixth embodiment have the same effects as the pressure sensor 510 and membrane electrode structure M5 in terms of their common parts.

[0119] Seventh Embodiment Figure 11 is a conceptual diagram illustrating the membrane electrode structure M7 of the pressure sensor 710 according to the seventh embodiment, using a top view (Figure 11(a)) and a cross-sectional view (Figure 11(b)). The membrane electrode structure M7 differs from the membrane electrode structure M2 of the pressure sensor 210 shown in Figure 6 in that the second electrode portion 762 is located on the upper surface 490a of the protective film 490. However, the pressure sensor 710 and membrane electrode structure M7 are similar to the pressure sensor 210 and membrane electrode structure M2 of the second embodiment shown in Figure 6 in terms of the first electrode portion 261, metal stem 20, deformation detection portion 30, and insulating film 250, etc. In describing the membrane electrode structure M7 of the pressure sensor 710 according to the seventh embodiment, the differences from the pressure sensor 210 and membrane electrode structure M2 of the second embodiment will be explained, and the common points with the pressure sensor 210 and membrane electrode structure M2 will not be explained.

[0120] As shown in Figures 11(a) and 11(b), the film electrode structure M7 has a first electrode portion 261 similar to the film electrode structure M2 shown in Figure 6. That is, the first electrode portion 261 is formed on the film-forming surface 24 of the metal stem 20, and the insulating film 250 is formed on the first electrode portion 261, with a portion of it overlapping it.

[0121] On the other hand, the pressure sensor 210 has a protective film 490 formed to cover the insulating film 250 and the upper surface of the deformation detection unit 30, and the second electrode portion 762 of the film electrode structure M7 is provided on the upper surface 490a of the protective film 490. The second electrode portion 762 is made of a conductive film or the like, similar to the second electrode portion 62 shown in Figure 6.

[0122] The lower surface of the second electrode portion 762 constitutes a second contact region 762a that contacts the upper surface 490a of the protective film 490, and the upper surface of the second electrode portion 762 constitutes a second exposed region 762b that is exposed from the protective film 490. Although not shown in Figure 11(b), an intermediate wiring 82 is connected to the second exposed region 762b, similar to the second electrode portion 62 shown in Figure 3.

[0123] As shown in Figure 11(b), the first electrode portion 261 and the second electrode portion 762 face each other, with the insulating film 250 and the protective film 490 sandwiched between them. The delamination detection unit 70 (see Figure 4), which is electrically connected to the film electrode structure M7, detects the delamination of the insulating film 250 and the protective film 490 between the first and second electrode portions 762 by detecting a change in capacitance between the first electrode portion 261 and the second electrode portion 762. For example, the film electrode structure M7 can detect delamination occurring between the upper surface of the first electrode portion 261 and the lower surface 50b of the insulating film 250, or delamination occurring between the upper surface 250a of the insulating film 250 and the lower surface 490b of the protective film 490.

[0124] The membrane electrode structure M7 has multiple membranes sandwiched between the first electrode portion 261 and the second electrode portion 762, making it possible to simultaneously detect delamination occurring at three or more interfaces. Furthermore, the pressure sensor 710 and membrane electrode structure M7 according to the seventh embodiment have the same advantages as the pressure sensor 210 and membrane electrode structure M2 in terms of their common features.

[0125] Eighth Embodiment Figure 12 is a conceptual diagram illustrating the membrane electrode structure M8 of the pressure sensor 810 according to the eighth embodiment, using a top view. Figure 12(a) is a top view showing only the film-forming surface 24 of the metal stem 20 and the first electrode portion 841, and Figure 12(b) is a top view showing the entire pressure sensor 810. The arrangement and shape of the first electrode portion 841, the second electrode portion 842 and the insulating film 850 of the membrane electrode structure M8 differ from the membrane electrode structure M2 of the pressure sensor 210 shown in Figure 6. However, the basic structure of the pressure sensor 810 and the membrane electrode structure M8, in which the first electrode portion 841 and the second electrode portion 842 detect the peeling of the insulating film 850, is the same as that of the pressure sensor 210 and the membrane electrode structure M2 of the second embodiment shown in Figure 6, etc. In describing the membrane electrode structure M8 of the pressure sensor 810 according to the eighth embodiment, the explanation will focus on the differences from the pressure sensor 210 and membrane electrode structure M2 of the second embodiment, and the common points with the pressure sensor 210 and membrane electrode structure M2 will be omitted.

[0126] As shown in Figure 12(a), the first electrode portion 841 of the film electrode structure M8 has a first electrode first part 861 and a first electrode second part 866 that are separated from each other. Both the first electrode first part 861 and the first electrode second part 866 are formed on the film forming surface 24, and the upper surface of each part is in contact with the insulating film 850 shown in Figure 12(a).

[0127] As shown in Figure 12(b), a notch is formed in the insulating film 850, and a portion of the first electrode first portion 861 and the first electrode second portion 866 are exposed through the notch. That is, as shown in Figure 12(a), the upper surface of the first electrode first portion 861 has a first contact region 861a that contacts the lower surface of the insulating film 850 and a first exposed region 861b that is exposed from the insulating film 850. Similarly, the upper surface of the first electrode second portion 866 has a first contact region 866a that contacts the lower surface of the insulating film 850 and a first exposed region 866b that is exposed from the insulating film 850.

[0128] As shown in Figure 12(b), a deformation detection unit 30 for detecting deformation of the membrane 22 on the metal stem 20 and a second electrode portion 842 of the film electrode structure M8 are formed on the upper surface of the insulating film 850. The second electrode portion 842 of the film electrode structure M8 has a second electrode first portion 862 and a second electrode second portion 867 that are separated from each other.

[0129] As shown in Figure 12(b), at least a portion of the first portion 862 of the second electrode faces the first portion 861 of the first electrode across the insulating film 850, and at least a portion of the second portion 867 of the second electrode faces the second portion 866 of the first electrode across the insulating film 850. In the film electrode structure M8, delamination of the insulating film 850 is detected at two locations: the first portions 861 and 862, and the second portions 866 and 867.

[0130] Thus, the membrane electrode structure M8 of the pressure sensor 810 can detect delamination of the insulating film 850, which is a single film to be detected, at multiple locations spaced apart from each other. Therefore, for example, even when the insulating film 850 has multiple locations that are prone to delamination, the membrane electrode structure M8 can arrange the second electrode portion 842 in a manner that corresponds to the locations prone to delamination and does not overlap with the deformation detection portion 30.

[0131] Furthermore, it is preferable that the area of ​​at least one of the first electrode portion 841 and the second electrode portion 842 (the total area of ​​the first and second portions) is 1 / 50 or less of the area of ​​the insulating film 850 when viewed from a direction perpendicular to the insulating film 850. This makes it possible to appropriately arrange the first electrode portion 841 and the second electrode portion 842 without increasing the area of ​​the film-forming surface 24 and the insulating film 850, thereby realizing a compact pressure sensor 810 capable of detecting delamination.

[0132] Furthermore, the pressure sensor 810 and membrane electrode structure M8 according to the eighth embodiment have the same effects as the pressure sensor 210 and membrane electrode structure M2 in terms of their common features.

[0133] Ninth Embodiment Figure 13 is a top view of the membrane electrode structure M9 of the pressure sensor 910 according to the ninth embodiment. The membrane electrode structure M9 is the same as the membrane electrode structure M12 of the pressure sensor 110 according to the first modified example shown in Figure 5, except that the shape and arrangement of the second electrode portion 962 are different. In describing the membrane electrode structure M9 of the pressure sensor 910 according to the ninth embodiment, the differences from the pressure sensor 110 and membrane electrode structure M12 of the first modified example will be described, and the common points with the pressure sensor 110 and membrane electrode structure M12 will not be described.

[0134] As shown in Figure 13, the second electrode portion 962 of the film electrode structure M9 is formed on the upper surface of the insulating film 150 and faces the film-forming surface 24 of the metal stem 20, which functions as the first electrode portion, with the insulating film 150 in between. The second electrode portion 962 extends over the outer edge 150c of the insulating film 150, which is the film to be detected.

[0135] Since a portion of the outer edge 150c of the insulating film 150 is sandwiched between the film-forming surface 24c and the second electrode portion 962, the film electrode structure M9 can detect delamination occurring at the outer edge 150c of the insulating film 150. Furthermore, since the outer edge 150c can sometimes be the starting point of delamination in the insulating film 150, the film electrode structure M9 of the pressure sensor 910 can detect delamination of the insulating film 150 more quickly.

[0136] Furthermore, the pressure sensor 910 and membrane electrode structure M9 according to the ninth embodiment have the same effects as the pressure sensor 110 and membrane electrode structure M12 in terms of their common features.

[0137] Tenth Embodiment Figure 14 is a top view of the membrane electrode structure M10 of the pressure sensor 1010 according to the tenth embodiment. The membrane electrode structure M10 is the same as the membrane electrode structure M4 of the pressure sensor 410 according to the fourth embodiment shown in Figure 8, except that the shape and arrangement of the first electrode portion 1061, the second electrode portion 1062, and the protective film 1090 are different. In describing the membrane electrode structure M10 of the pressure sensor 1010 according to the tenth embodiment, the differences from the pressure sensor 410 and membrane electrode structure M4 of the fourth embodiment will be described, and the common points with the pressure sensor 410 and membrane electrode structure M4 will not be described.

[0138] As shown in Figure 14, the first electrode portion 1061 of the film electrode structure M10 is located on the upper surface of the insulating film 450, at a position corresponding to the notch 1090d of the protective film 1090. The upper surface of the first electrode portion 1061 has a first contact region 1061a that contacts the lower surface of the protective film 1090, and a first exposed region 1061b that is exposed from the protective film 1090. The first exposed region 1061b is exposed from the protective film 1090 through the outer edge 1090c of the notch 1090d, and the first electrode portion 1061 overlaps the outer edge 1090c of the protective film 1090.

[0139] The second electrode portion 1062 of the membrane electrode structure M10 is formed on the upper surface of the protective film 1090 and faces the first contact region 1061a of the first electrode portion 1061, with the protective film 1090 in between. The second electrode portion 1062, like the first electrode portion 1061, overlaps the outer edge portion 1090c of the protective film 1090, which is the film to be detected.

[0140] Since a portion of the outer edge 1090c of the protective film 1090 is sandwiched between the first electrode portion 1061 and the second electrode portion 1062, the membrane electrode structure M10 can detect delamination occurring at the outer edge 1090c of the protective film 1090. Furthermore, since delamination tends to occur more easily at the outer edge 1090c of the notch 1090d than at other parts of the protective film 1090, the membrane electrode structure M10 of the pressure sensor 1010 can more accurately detect whether or not delamination has occurred in the protective film 1090.

[0141] As shown in Figure 13 (membrane electrode structure M9) and Figure 14 (membrane electrode structure M10), if at least one of the first electrode portion 1061 and the second electrode portions 962, 1062 overlaps the outer edges 150c, 1090c of the film to be detected (insulating film 150 or protective film 1090), the peeling of the film to be detected can be detected more sensitively. Furthermore, the pressure sensor 1010 and membrane electrode structure M10 according to the 10th embodiment have the same effects as the pressure sensor 410 and membrane electrode structure M4 in terms of their common features.

[0142] Eleventh Embodiment Figure 15 is an external view of the pressure sensor 1110 according to the 11th embodiment. The membrane electrode structure M2 of the pressure sensor 1110 is the same as the membrane electrode structure M2 of the pressure sensor 210 shown in Figure 6. The pressure sensor 1110 is the same as the pressure sensor 210 according to the second embodiment shown in Figure 6, except that the wiring route of the first electrode portion 261 of the membrane electrode structure M2 to the circuit board 1180 is different. In describing the pressure sensor 1110 according to the 11th embodiment, the differences from the pressure sensor 210 of the second embodiment will be described, and the similarities with the pressure sensor 210 will not be described.

[0143] As shown in Figure 15, the metal stem 20 of the pressure sensor 1110 is attached to the connecting member 12 by a retaining member 14. The circuit board 1180 is also fixed to the retaining member 14 by a metal screw 1194.

[0144] Unlike the first electrode portion 261 of the pressure sensor 210, the first electrode portion 261 of the membrane electrode structure M2 of the pressure sensor 1110 (see Figure 6(b)) is electrically connected to the circuit board 1180 and the peel detection unit located outside the circuit board 1180 via a metal stem 20 or the like, rather than via an intermediate wiring 82.

[0145] In other words, the metal stem 20, retaining member 14, and screw 1194 of the pressure sensor 1110 are all made of conductive material and are in contact with each other. Also, the screw 1194 is in contact with the pad 1195 of the circuit board 1180. Therefore, the pad 1195 of the circuit board 1180 is electrically connected to the first electrode portion 261 (see Figure 6(b)) formed on the film-forming surface 24 of the metal stem 20 via the metal stem 20, retaining member 14, and screw 1194.

[0146] In the pressure sensor 1110, the first electrode portion 261 is electrically connected to the peel detection portion via a metal stem 20 or the like, which reduces the number of intermediate wirings 82 made by wire bonding and contributes to improved productivity.

[0147] Figure 16 is an external view of the pressure sensor 1210 according to a second modified example. Similar to the pressure sensor 1110 shown in Figure 15, the pressure sensor 1210 electrically connects the first electrode portion 261 to the peel detection portion via a metal stem 20, etc. In the pressure sensor 1210, the connector pin 1296 that contacts the retaining member 14 is electrically connected to the first electrode portion 261 (see Figure 6(b)) formed on the film-forming surface 24 of the metal stem 20 via the metal stem 20 and the retaining member 14.

[0148] The connector pin 1296 is further electrically connected to an external peel detection unit. The pressure sensor 1210 is the same as the pressure sensor 210 according to the second embodiment, except that the connector pin 1296 and the first electrode portion 261 are electrically connected.

[0149] Figure 17 is an external view of the pressure sensor 1310 according to the third modified example. Similar to the pressure sensor 1110 shown in Figure 15, the pressure sensor 1310 electrically connects the first electrode portion 261 to the peel detection portion via a metal stem 20, etc. In the pressure sensor 1310, a conductive wire 1397 that contacts the retaining member 14 is electrically connected to the first electrode portion 261 (see Figure 6(b)) formed on the film-forming surface 24 of the metal stem 20 via the metal stem 20 and the retaining member 14.

[0150] The wire 1397 is electrically connected to the external delamination detection unit, similar to the connector pin 1296 shown in Figure 16. The pressure sensor 1310 is the same as the pressure sensor 210 according to the second embodiment, except that the wire 1397 and the first electrode portion 261 are electrically connected.

[0151] Thus, the pressure sensors 1210 and 1310 according to the second and third modified examples also electrically connect the first electrode portion 261 to the peel detection portion via a metal stem 20 or the like, similar to the pressure sensor 1110, resulting in good productivity.

[0152] Although the film electrode structures M1 to M10, M12 and pressure sensors 10 to 1310 have been described above with reference to embodiments and modifications, it goes without saying that the present invention is not limited to these embodiments and includes many other embodiments and modifications. For example, the film to be detected for delamination is not limited to insulating films or protective films, but may also be a film that detects delamination of other insulating or conductive films. Furthermore, the delamination detection unit is not limited to one that detects changes in capacitance. For example, if the film to be detected is a conductive film or semiconductor film, a delamination detection unit that detects delamination by changing the resistance value between electrodes can be used. [Explanation of Symbols]

[0153] 10, 110, 210, 310, 410, 510, 610, 710, 810, 910, 1010, 1110, 1210, 1310… Pressure sensors M1, M2, M3, M4, M5, M6, M7, M8, M9, M10, M12...Membrane electrode structure 12…Connecting member 12a... Screw groove 12b...flow channel 14…Retaining member 20…Metal stem 21…Flange section 22...Membrane 23…Inner self 24...Film forming surface 24a...first contact area 24aa, 324aa...1st opposing part 24b…1st exposure area 30...Deformation detection unit R1, R2, R3, R4...Resistor 32, 332... Detection electrode section 34…Electrical wiring 334... Distortion Resistive Film 50, 150, 250, 450, 850… Insulating film 50a, 150a, 250a, 450a...Top surface 50b, 150b, 250b…bottom surface 150c... outer edge 261, 461, 541, 641, 841, 1061...first electrode part 561, 861...First electrode first part 566, 866...First electrode second part 261a, 461a, 1061a...first contact area 261aa...First opposing section 261b, 461b, 1061b...first exposure area 62, 362, 462, 542, 642, 762, 842, 1062...Second electrode part 562, 662, 862...Second electrode first part 567, 867...Second electrode second part 62a, 462a, 762a...Second contact area 62b, 462b, 762b…Second exposure area 64, 164... connection part 70... Peeling detection unit 80... Circuit board 82, 182...Intermediate wiring 490, 1090...Protective film 490a…Top surface 490b…Bottom surface 1090c... outer edge 1090d... Notch 1194... Screw 1195... pad 1296… Connector pins 1397... Wire

Claims

1. The insulating film that is the target of delamination detection, A first electrode portion that contacts the lower surface of the insulating film, It has a second electrode portion that is in contact with the upper surface of the insulating film and at least a portion of which faces the first electrode portion across the insulating film, The first electrode portion has a first contact region that is in contact with the insulating film and includes a first opposing portion that faces the second electrode portion, and a first exposed region that is exposed from the insulating film in a plan view as seen from the upper surface of the insulating film. The second electrode portion has a second contact region that is in contact with the insulating film and includes a second opposing portion that faces the first electrode portion, and a second exposed region that is exposed from the insulating film. The first electrode portion is electrically connected to a peel detection unit that detects the peeling of the insulating film between the first electrode portion and the second electrode portion via the first exposed region. The second electrode portion is electrically connected to the peel detection portion via the second exposed region, The insulating film is formed on the film-forming surface of the stainless steel stem. The insulating film is a film electrode structure comprising at least one of silicon oxide, silicon nitride, and silicon oxynitride.

2. The film electrode structure according to claim 1, wherein the first electrode portion is composed of a conductive film, and the first contact region and the first exposed region are arranged on the same plane.

3. The first electrode portion has a film-forming surface on which the insulating film is formed, and the film-forming surface is in contact with the lower surface of the insulating film. The film electrode structure according to claim 1, wherein both the first contact region and the first exposed region are part of the film-forming surface and are arranged on the same surface.

4. The film electrode structure according to claim 1 or claim 2, wherein the insulating film includes a protective film that covers and protects the member formed on the lower side.

5. The film electrode structure according to any one of claims 1 to 4, wherein, when viewed from a direction perpendicular to the insulating film, the area of ​​at least one of the first electrode portion and the second electrode portion is 1 / 50 or less of the area of ​​the insulating film.

6. The first electrode portion comprises a first electrode first portion and a first electrode second portion that are separated from each other. The second electrode portion has a first portion of the second electrode and a second portion of the second electrode that are separated from each other. At least a portion of the first portion of the second electrode faces the first portion of the first electrode across the insulating film, The film electrode structure according to any one of claims 1 to 5, wherein at least a portion of the second portion of the second electrode faces the second portion of the first electrode across the insulating film.

7. The film electrode structure according to any one of claims 1 to 6, wherein at least one of the first electrode portion and the second electrode portion extends over the outer edge of the insulating film.

8. The insulating film that is the target of delamination detection, A first electrode portion that contacts the lower surface of the insulating film, It has a second electrode portion that is in contact with the upper surface of the insulating film and at least a portion of which faces the first electrode portion across the insulating film, The first electrode portion has a first contact region that is in contact with the insulating film and includes a first opposing portion that faces the second electrode portion, and a first exposed region that is exposed from the insulating film. The lower surface of the insulating film is in contact with the first electrode portion and a film-forming surface made of a different material from the first electrode portion, and the adhesion force with the first electrode portion is smaller than the adhesion force with the film-forming surface. The second electrode portion has a second contact region that is in contact with the insulating film and includes a second opposing portion that faces the first electrode portion, and a second exposed region that is exposed from the insulating film. The first electrode portion is electrically connected to a peel detection unit that detects the peeling of the insulating film between the first electrode portion and the second electrode portion via the first exposed region. The second electrode portion is a film electrode structure that is electrically connected to the peel detection portion via the second exposed region.

9. The insulating film is formed on the film-forming surface of the stainless steel stem. The film electrode structure according to claim 8, wherein the insulating film comprises at least one of silicon oxide, silicon nitride, and silicon oxynitride.

10. The film electrode structure according to claim 1, wherein the peel detection unit detects the capacitance between the first electrode portion and the second electrode portion.

11. A membrane electrode structure according to any one of claims 1 to 10, A pressure sensor having a deformation detection unit formed on the lower or upper side of the insulating film for detecting deformation of the membrane due to pressure.

12. The aforementioned membrane is part of a stainless steel stem, The pressure sensor according to claim 11, wherein the first electrode portion is electrically connected via the stem to a delamination detection portion that detects the delamination of the insulating film between the first electrode portion and the second electrode portion.

13. An insulating film to be the target of peel detection, A first electrode portion that contacts the lower surface of the insulating film, It has a second electrode portion that is in contact with the upper surface of the insulating film and at least a portion of which faces the first electrode portion across the insulating film, The first electrode portion has a first contact region that is in contact with the insulating film and includes a first opposing portion that faces the second electrode portion, and a first exposed region that is exposed from the insulating film in a plan view as seen from the upper surface of the insulating film. The second electrode portion has a second contact region that is in contact with the insulating film and includes a second opposing portion that faces the first electrode portion, and a second exposed region that is exposed from the insulating film. The first electrode portion is electrically connected to a peel detection unit that detects the peeling of the insulating film between the first electrode portion and the second electrode portion via the first exposed region. The second electrode portion comprises a film electrode structure that is electrically connected to the peel detection portion via the second exposed region, A pressure sensor having a deformation detection unit formed on the lower or upper side of the insulating film for detecting deformation of the membrane due to pressure.

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