WO2023238520A1

WO2023238520A1 - Pressure switch

Info

Publication number: WO2023238520A1
Application number: PCT/JP2023/015595
Authority: WO
Inventors: 賢周森本
Original assignee: 株式会社大真空
Priority date: 2022-06-07
Filing date: 2023-04-19
Publication date: 2023-12-14

Abstract

Provided is a high-quality pressure switch.　The present invention comprises: a base substrate 2; a lid substrate 3 that, by being bonded to the base substrate 2, forms an airtight space between the lid substrate 3 and the base substrate 2; a deformable diaphragm 5 that is formed at a position corresponding to the airtight-space of the lid substrate 3; a lid-side movable contact electrode 8 that is disposed on the diaphragm 5 and serves as a movable contact; and a base-side fixed contact electrode 11 that faces the lid-side movable contact electrode 8 with a prescribed gap therebetween and serves as a fixed contact. An electrical connection is toggled by the lid-side movable contact electrode 8 and the base-side fixed contact electrode 11 coming into contact or separating due to deformation of the diaphragm 5. The base substrate 2, the lid substrate, and the diaphragm 5 are each formed from quartz or glass.

Description

pressure switch

The present invention relates to a pressure switch in which a movable contact and a fixed contact or other movable contact come into contact with or separate from each other due to deformation of a diaphragm due to external pressure changes.

BACKGROUND ART Conventionally, there have been pressure switches in which a movable contact and a fixed contact are brought into contact with each other or separated from each other by deformation of a diaphragm due to external pressure changes; for example, there is a pressure switch disclosed in Patent Document 1.

In the pressure switch disclosed in Patent Document 1, a first substrate having a diaphragm that can be deformed by an external force and a second substrate are overlapped, and a gap between the first substrate and the second substrate is formed. A closed space is formed in the closed space, and a contact mechanism arranged within the closed space is opened and closed based on the deformation of the diaphragm. In the contact mechanism, a movable contact is provided on the surface of the first substrate facing the second substrate at a position corresponding to the diaphragm, and a movable contact is provided on the surface of the second substrate facing the first substrate. A fixed contact is provided opposite to the diaphragm and comes into contact with the movable contact based on the deformation of the diaphragm. Silicon is used as a material constituting the first substrate having the diaphragm, and gold is used as a material constituting the movable contact provided on the surface of the first substrate facing the second substrate.

Japanese Patent Application Publication No. 2001-176365

In the pressure switch disclosed in Patent Document 1, a diaphragm is formed by thinning a part of the silicon substrate, but there is a risk of damage due to repeated on/off operations of the switch, making it difficult to obtain a high-quality pressure switch. requested.

In view of the above problems, the present invention aims to provide a high quality pressure switch.

In order to achieve the above object, the pressure switch according to the present invention includes a first substrate and a second substrate that is bonded to the first substrate to form an airtight space between the first substrate and the second substrate. a diaphragm formed at a position corresponding to the airtight space and deformed by external pressure changes; and a diaphragm disposed on the diaphragm and movable. a first contact forming a contact; and a second contact facing the first contact at a predetermined distance and forming a fixed contact or another movable contact; The electrical connection is switched by the first contact and the second contact coming into contact with each other or being separated from each other, and the diaphragm is made of crystal.

According to this configuration, the diaphragm is formed of crystal. When the diaphragm is made thinner, the sensitivity as a pressure switch is improved, but the diaphragm lacks strength and becomes easily damaged. On the other hand, if the thickness of the diaphragm is increased, the strength can be ensured, but the sensitivity as a pressure switch will decrease. Therefore, in order to satisfy sensitivity and strength, it is necessary to keep the thickness of the diaphragm within a predetermined range. It is known that the thickness of crystal depends on the resonant frequency, and by controlling the resonant frequency of the diaphragm to a value corresponding to the desired thickness, a diaphragm with a desired thickness can be easily formed. Therefore, a high quality pressure switch with an optimized balance between strength and sensitivity can be formed. Further, by using crystal as the material for forming the diaphragm, a large number of pressure switches can be manufactured at once using, for example, wet etching or photolithography technology, and an inexpensive pressure switch can be provided.

Further, in order to achieve the above object, another pressure switch according to the present invention provides an airtight space between a first substrate and the first substrate by being joined to the first substrate. a second substrate to be formed, a diaphragm formed at a position corresponding to the airtight space and deformed by external pressure changes, and at least one of the first substrate and the second substrate; a first contact that is arranged to form a movable contact; and a second contact that faces the first contact at a predetermined distance and serves as a fixed contact or another movable contact, and the diaphragm is deformed. The electrical connection is switched by the first contact and the second contact coming into contact with each other or being separated from each other, and the diaphragm is made of glass.

According to this configuration, the diaphragm is made of glass. Since glass is an amorphous and isotropic material, for example, when a diaphragm is formed by etching a glass substrate, the amount of etching can be made uniform regardless of the direction, resulting in a diaphragm with excellent shape symmetry. A diaphragm can be formed. Furthermore, since glass has a smaller Young's modulus than quartz, it is relatively easier to deform than quartz, making it easier to ensure strength.

Furthermore, the first substrate and the second substrate may be made of the same material.

According to this configuration, when the first substrate and the second substrate are bonded, it is possible to prevent stress caused by the difference in linear expansion coefficients of both substrates.

Further, the diaphragm is formed by making a part of the first substrate and/or the second substrate on which the diaphragm is formed thinner than other parts, and the diaphragm is formed by The part and the other part may be integrally formed.

According to this configuration, even if the diaphragm is made thinner, the mechanical strength of the diaphragm can be maintained.

Furthermore, the first substrate and the second substrate may have the same thickness.

According to this configuration, when the first substrate and the second substrate are bonded, warping of the bonded body of the first substrate and the second substrate due to the stress difference between the two substrates can be suppressed. I can do it.

Furthermore, the first substrate and the second substrate may be bonded via a metal film.

According to this configuration, gas is not generated during bonding as in the case where the first substrate and the second substrate are bonded using a conductive adhesive, so that the first substrate can be bonded in an environment with little unintended gas. An airtight space can be formed between the first substrate and the second substrate. Furthermore, since the pressure within the airtight space can be easily controlled, the operating pressure of the pressure switch can be precisely controlled.

According to the invention, the diaphragm is formed of quartz. It is known that the thickness of crystal depends on the resonant frequency, and by controlling the resonant frequency of the diaphragm to a value corresponding to the desired thickness, a diaphragm with a desired thickness can be easily formed. Therefore, a high quality pressure switch with an optimized balance between strength and sensitivity can be formed.
Further, by using crystal as the material for forming the diaphragm, a large number of pressure switches can be manufactured at once using, for example, wet etching or photolithography technology, and an inexpensive pressure switch can be provided.

(a) is a sectional view of the pressure switch according to the first embodiment of the present invention under vacuum, and (b) is a sectional view of the pressure switch under atmospheric pressure. FIG. 2 is a plan view of the pressure switch according to the first embodiment, in which (a) is a view when viewed directly from the lower surface of the lid board, and (b) is a view when viewed from directly against the upper surface of the base board. , (c) are views when viewed directly from the bottom surface of the base substrate. (a) is a cross-sectional view of a pressure switch according to a second embodiment of the present invention under vacuum, and (b) is a cross-sectional view of the pressure switch under atmospheric pressure. (a) is a sectional view of a pressure switch according to a third embodiment of the present invention under vacuum, and (b) is a sectional view of the pressure switch under atmospheric pressure. (a) is a cross-sectional view of a pressure switch according to a fourth embodiment of the present invention under vacuum, and (b) is a cross-sectional view of the pressure switch under atmospheric pressure. (a) is a cross-sectional view of a pressure switch according to a fifth embodiment of the present invention under vacuum, and (b) is a cross-sectional view of the pressure switch under atmospheric pressure. (a) is a cross-sectional view of a pressure switch according to a sixth embodiment of the present invention under vacuum, and (b) is a cross-sectional view of the pressure switch under atmospheric pressure. (a) is a cross-sectional view of a pressure switch according to a seventh embodiment of the present invention under vacuum, and (b) is a cross-sectional view of the pressure switch under atmospheric pressure. (a) is a sectional view of a pressure switch according to an eighth embodiment of the present invention under vacuum, and (b) is a sectional view of the pressure switch under atmospheric pressure. It is a figure for explaining the ratio (D/t) of the diameter D of a diaphragm to the thickness t of the said diaphragm. FIG. 2 is a diagram showing the shape of a recess when the base substrate and lid substrate of FIG. 1 are formed of glass. (a) is a cross-sectional view of a pressure switch according to a ninth embodiment of the present invention under vacuum, and (b) is a cross-sectional view of the pressure switch under atmospheric pressure. It is a top view of the pressure switch according to the ninth embodiment, (a) is a view when viewed directly from the lower surface of the lid board, and (b) is a view when viewed from directly against the upper surface of the base board. , (c) are views when viewed directly from the bottom surface of the base substrate. (a) is a cross-sectional view of a pressure switch according to a tenth embodiment of the present invention under vacuum, and (b) is a cross-sectional view of the pressure switch under atmospheric pressure. (a) is a cross-sectional view of a pressure switch according to an eleventh embodiment of the present invention under vacuum, and (b) is a cross-sectional view of the pressure switch under atmospheric pressure. (a) is a cross-sectional view of a pressure switch according to a twelfth embodiment of the present invention under vacuum, and (b) is a cross-sectional view of the pressure switch under atmospheric pressure. (a) is a sectional view of a pressure switch according to a thirteenth embodiment of the present invention under vacuum, and (b) is a sectional view of the pressure switch under atmospheric pressure. (a) is a cross-sectional view of a pressure switch according to a fourteenth embodiment of the present invention under vacuum, and (b) is a cross-sectional view of the pressure switch under atmospheric pressure. (a) is a sectional view of a pressure switch according to a fifteenth embodiment of the present invention under vacuum, and (b) is a sectional view of the pressure switch under atmospheric pressure. (a) is a cross-sectional view of a pressure switch according to a sixteenth embodiment of the present invention under vacuum, and (b) is a cross-sectional view of the pressure switch under atmospheric pressure. It is a figure for explaining the ratio (D/t) of the diameter D of a diaphragm to the thickness t of the said diaphragm. FIG. 13 is a diagram showing the shape of a recess when the base substrate and lid substrate of FIG. 12 are formed of glass.

Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings. In the description of the first embodiment and each embodiment described later, the top, bottom, left, and right of the paper surface of FIG. 1 will be referred to as "top," "bottom," "left," and "right," respectively.

<<First embodiment>>
A pressure switch 1 according to a first embodiment of the present invention will be described with reference to FIGS. 1 and 2.

A pressure switch 1 according to a first embodiment of the present invention is a switch whose electrical connection is switched according to a change in external pressure, and has a base substrate 2 and a lid substrate 3, as shown in FIG. The pressure switch 1 is placed, for example, in a closed space and used as a switch that detects whether airtightness within the closed space is ensured. The pressure switch 1 is connected to an IC having a determination function, and by determining the on/off state of the pressure switch 1, the IC determines whether airtightness in the closed space is ensured.

The lid substrate 3 is made of AT-cut crystal. The upper surface 30a and lower surface 30b of the lid substrate 3 are mirror-finished (polished), and their flatness (TTV) is, for example, 0.15 μm or less. It is assumed that AT-cut crystal is used as the material for the lid substrate 3, but the material is not limited to this, and cut crystals whose resonance frequency depends on the thickness, such as BT-cut crystal and SC-cut crystal, may be used. You may also use Note that in each of the first to eighth embodiments, crystal is used as the material for each substrate, but the material is not limited to this, and for example, glass may be used. . When glass is used, a diaphragm with excellent shape symmetry can be formed.

The lid board 3 has a substantially rectangular shape in plan view when viewed from the upper side to the lower side in FIG. A depression 4 (recess) having a substantially circular shape in plan view is formed in the center of the surface (opposite surface), and a thin diaphragm 5 is formed at the bottom of the depression 4. ing. The recess 4 can be formed, for example, by wet etching the formation region of the recess 4 on the upper surface 30a of the lid substrate 3 using photolithography technology.

The thickness of the diaphragm 5 (the thickness in the vertical direction in the drawing) is such that it can be relatively easily deformed in the thickness direction (in the vertical direction in the drawing) by external force, and the diaphragm 5 is easily damaged. The thickness is preferably 5 μm or more and 15 μm or less, and more preferably 8 μm or more and 10 μm or less.

In the lid substrate 3, the peripheral portion of the thin diaphragm 5 formed on the upper surface 30a of the lid substrate 3 in plan view is thicker than the diaphragm 5, and is thicker than the diaphragm 5 and the diaphragm 5. A thick wall portion 6 (hereinafter appropriately referred to as a “base portion”) is integrally molded from the same material.

For example, in this embodiment, the thickness of the lid substrate 3 (thickness of the base portion 6) is approximately 40 μm, while the thickness of the diaphragm 5 is approximately 10 μm. Note that there is a correlation between the thickness of the crystal substrate and its resonant frequency; for example, when the thickness of the substrate is t [mm] and the resonant frequency is F [kHz], the relationship F=1670/t holds true. Therefore, after forming the diaphragm 5, the thickness of the manufactured diaphragm can be estimated by measuring the resonance frequency.

The base substrate 2 is made of AT-cut crystal. Although AT-cut crystal is used as the material for the base substrate 2, the present invention is not limited to this, and BT-cut crystal, SC-cut crystal, or the like may also be used. Note that in each of the first to eighth embodiments, crystal is used as the material for each substrate, but the material is not limited to this, and for example, glass may be used. . Note that it is preferable that the lid substrate 3 and the base substrate 2 be formed of the same material.

The base substrate 2 has a substantially rectangular shape in plan view when viewed from the upper side to the lower side in FIG. A depression 7 (concave portion) having a substantially circular shape in plan view is formed in the substantially center portion in plan view. This depression 7 is located at a position facing the diaphragm 5 formed on the lid substrate 3 when the pressure switch 1 is assembled, and when the lid substrate 3 and the base substrate 2 are joined as described later, A lid-side movable contact electrode 8 forming a movable contact to be described later and a base-side fixed contact electrode 11 forming a fixed contact to be described later are arranged to form an airtight space in which the diaphragm 5 can be deformed. Note that the depression 7 can also be formed by, for example, wet etching the formation region of the depression 7 on the upper surface 20a of the base substrate 2 using photolithography technology.

In the base substrate 2, the surrounding portion of the recess 7 formed on the upper surface 20a of the base substrate 2 in plan view is thicker than the portion of the recess 7, and the portion of the recess 7 and the thick portion are thicker than the portion of the recess 7. are integrally formed from the same material.

In this embodiment, the thickness of the base substrate 2 (thickness of the thick portion of the base substrate 2) is approximately 40 μm, which is the same as the thickness of the lid substrate 3 (thickness of the base portion 6). The depth of the depression 7 (concave portion) of the base substrate 2 is 0.5 μm. As a result, if the diaphragm 5 is not deformed in a state where the lid substrate 3 and the base substrate 2 are joined, the lid side movable contact electrode 8 formed on the diaphragm 5 side and the base substrate The base side fixed contact electrode 11 formed on the second side is separated from the base side fixed contact electrode 11 formed on the second side.

Next, each electrode formed on the lid substrate 3 and the base substrate 2 will be explained with reference to FIG. 2. 2A and 2B are diagrams for explaining various electrodes, in which (a) is a diagram when viewed directly from the bottom surface of the lid substrate 3, and (b) is a diagram when viewed from the top surface of the base substrate 2. (c) shows a view when viewed directly from the bottom surface of the base substrate 2.

On the lower surface 30b of the lid substrate 3, a lid-side movable contact electrode 8 forming a movable contact of the pressure switch 1, and a lid-side first bonding electrode 9 integrally formed with the lid-side movable contact electrode 8 are provided. , a lid-side second bonding electrode 10 that is not in contact with either the lid-side movable contact electrode 8 or the lid-side first bonding electrode 9 is formed.

As shown in FIG. 2(a), in this embodiment, the lid-side second bonding electrode 10 has a shape in which the right side of a vertically long rectangle is cut out in an arc shape, and the lower surface 30b of the lid substrate 3 , it is formed in a region corresponding to the thick portion 6 and on the left side of the region where the circular diaphragm 5 is formed.

The lid-side first bonding electrode 9 is formed to cover substantially all of the area on the lower surface 30b of the lid substrate 3 corresponding to the thick portion 6 where the lid-side second bonding electrode 10 is not formed. They are formed at predetermined intervals so as not to contact the lid-side second bonding electrode 10.

As shown in FIG. 2(a), the lid-side movable contact electrode 8 is formed to extend toward the center of the diaphragm 5 from the end of the lid-side first bonding electrode 9 on the side closer to the diaphragm 5. By doing so, it is arranged in the formation region (thin wall portion) of the diaphragm 5.

The lid-side first bonding electrode 9, the lid-side second bonding electrode 10, and the lid-side movable contact electrode 8 are connected to the first Ti film laminated on the lower surface 30b of the lid substrate 3, and the first Ti film laminated on the lower surface 30b of the lid substrate 3, respectively. a first Au film laminated on the Ti film, a second Ti film laminated on the first Au film, and a second Au film laminated on the second Ti film. It consists of However, regarding the lid-side movable contact electrode 8, the uppermost second Au film is removed by etching, and the uppermost layer is made of a second Ti film. For example, the thickness of the first Ti film laminated on the lower surface 30b of the lid substrate 3 is 300 Å, the thickness of the first Au film one layer above it is 2000 Å, and the thickness of the second Ti film one layer above it is 300 Å. The film thickness is 300 Å, and the thickness of the second Au film one layer above it is 1000 Å. Note that in this embodiment, each metal film is formed by a sputtering method at a high temperature (for example, 150° C. to 200° C.), but other film forming methods such as a vapor deposition method can be employed.

Note that among the metal films, the main conductive film is the Au film, but the Au film has relatively low adhesion strength to the lid substrate 3 made of crystal. Therefore, a Ti film having relatively high adhesion strength to the lid substrate 3 is formed on the lower surface 30b of the lid substrate 3 as a base metal film. Since Au films tend to come into close contact with each other, if the top layer of the lid-side movable contact electrode 8 and the top layer of the base-side fixed contact electrode 11 are both Au films, for example, When they come into contact, there is a risk that they will come into close contact with each other and be unable to separate. In order to prevent this, the metals constituting the top layers of the lid side movable contact electrode 8 and the base side fixed contact electrode 11 are made of Au on one side and Ti on the other side. Note that the metal forming the film corresponding to each Ti film is not limited to Ti, and may be, for example, Cr, Ni, W, Mo, or an alloy thereof.

On the upper surface 20a of the base substrate 2, a base-side fixed contact electrode 11 forming a fixed contact of the pressure switch 1, a base-side second bonding electrode 12 formed integrally with the fixed contact electrode 11, and a base A base-side first bonding electrode 13 that is not in contact with either the side fixed contact electrode 11 or the base-side second bonding electrode 12 is formed.

As shown in FIG. 2(b), in this embodiment, the base-side second bonding electrode 12 has a shape in which the right side of a vertically long rectangle is cut out in an arc shape, and the upper surface 20a of the base substrate 2 , it is formed adjacent to the region on the left side of the region where the circular depression 7 (concave portion) is formed.

The base-side first bonding electrode 13 is formed on the upper surface 20a of the base substrate 2 so as to cover substantially all of the region where the recess 7 (concave portion) is formed and the portion where the base-side second bonding electrode 12 is not formed. They are formed at predetermined intervals so as not to contact the base-side second bonding electrode 12.

As shown in FIG. 2(b), the base-side fixed contact electrode 11 extends from the end of the base-side second bonding electrode 12 closer to the recess 7 (recess) toward the center of the recess 7 (recess). formed to extend. Specifically, the base-side fixed contact electrode 11 extends from the end of the base-side second bonding electrode 12 to the side wall of the recess 7 (recess) and further to the center of the bottom of the recess 7 (recess). exists and is formed. Since the recess 7 (concave portion) is provided at a position facing the diaphragm 5, when the diaphragm 5 is not deformed, the base side fixed contact electrode 11 and the lid side movable contact electrode 8 are separated by a predetermined distance. They face each other, and the deformation of the diaphragm 5 switches the contact/separation between the base-side fixed contact electrode 11 and the lid-side movable contact electrode 8.

The base-side first bonding electrode 13, the base-side second bonding electrode 12, and the base-side fixed contact electrode 11 all have a first Ti film laminated on the upper surface 20a of the base substrate 2, and a first Ti film laminated on the upper surface 20a of the base substrate 2. a first Au film laminated on the Ti film, a second Ti film laminated on the first Au film, and a second Au film laminated on the second Ti film. It consists of However, in the base side fixed contact electrode 11, unlike the lid side movable contact electrode 8, the second Au film of the uppermost layer is not removed by etching, and the uppermost layer is composed of the second Au film. . For example, the thickness of the first Ti film laminated on the upper surface 20a of the base substrate 2 is 300 Å, the thickness of the first Au film one layer above it is 2000 Å, and the thickness of the second Ti film one layer above it is 300 Å. The film thickness is 300 Å, and the thickness of the second Au film one layer above it is 1000 Å. In this embodiment, each metal film is formed by sputtering, but other film forming methods such as vapor deposition can be used. Note that the metal forming the film corresponding to each Ti film is not limited to Ti, and may be, for example, Cr, Ni, W, Mo, or an alloy thereof. Further, the base side fixed contact electrode 11 is composed of a first Ti film laminated on the upper surface 20a of the base substrate 2 and a first Au film laminated on the first Ti film. (It is composed of a base metal layer (first Ti film) and a single metal layer (first Au film) on the base metal layer (first Ti film)). In addition, the film structure of the lid side movable contact electrode 8 is replaced with the film structure of the base side fixed contact electrode 11 described above, and the film structure of the base side fixed contact electrode 11 is replaced with the film structure of the lid side movable contact electrode 8 described above. It may be replaced with the configuration.

As shown in FIG. 2(c), on the lower surface 20b of the base substrate 2, there is a first external connection electrode 14a for external connection in a vertically long rectangular shape at the right end and a first external connection electrode 14a for external connection in a vertically long rectangular shape at the left end. A second external connection electrode 14b is formed. The first external connection electrode 14a and the second external connection electrode 14b are each connected to a predetermined land electrode formed on the mounting surface of another substrate on which the pressure switch 1 is mounted. The predetermined land electrode and a predetermined terminal of an IC mounted on the other board are connected via a wiring electrode formed on the other board.

Note that the first external connection electrode 14a and the second external connection electrode 14b and the land electrode of the other substrate can be bonded, for example, with a conductive adhesive. Alternatively, metal bumps such as Au bumps may be formed on the first external connection electrode 14a and the second external connection electrode 14b, and they may be joined by ultrasonic bonding. Further, the top surface 30a of the lid substrate 3 and the mounting surface of another substrate are arranged so as to face each other and fixed with a non-conductive adhesive or the like, and the first external connection electrode 14a and the second external connection electrode 14b are connected to each other. It may also be connected to a predetermined land electrode by wire bonding.

The first external connection electrode 14a and the second external connection electrode 14b are, for example, a Ti film/ A multilayer structure of Au film/Ti film/Au film may be used. Thereby, the base-side first bonding electrode 13, the base-side second bonding electrode 12, and the base-side fixed contact electrode 11 can be formed simultaneously.

The base substrate 2 includes a first interlayer connection conductor 15a that connects the first external connection electrode 14a formed on the bottom surface 20b and the base-side first bonding electrode 13 formed on the top surface 20a, and a first interlayer connection conductor 15a formed on the bottom surface 20b. A second interlayer connection conductor 15b is formed to connect the second external connection electrode 14b and the base-side second bonding electrode 12 formed on the upper surface 20a. The first and second interlayer connection conductors 15a and 15b are each formed of, for example, a through hole whose inner wall surface is coated with a metal film. As a manufacturing method, for example, a through hole is formed at a predetermined location of the base substrate 2, and then the first external connection electrode 14a, the second external connection electrode 14b, the base side first bonding electrode 13, and the base side second bonding electrode are formed. When forming the electrode 12 for the base side and the electrode 11 for the base side fixed contact, a metal film having the same structure can be formed on the inner wall surface of the through hole as well. Note that the first and second interlayer connection conductors 15a and 15b may be formed using vias whose through holes are separately filled with a conductive material such as metal paste.

The base substrate 2 and the lid substrate 3 are bonded to each other by connecting the lid-side first bonding electrode 9 and the lid-side second bonding electrode 10 formed on the bottom surface 30b of the lid substrate 3 and the top surface 20a of the base substrate 2. The bonding is performed by joining the base-side first bonding electrode 13 and the base-side second bonding electrode 12. Specifically, the lid substrate 3 is laminated on the base substrate 2 under vacuum. At this time, the lid-side first bonding electrode 9 and the base-side first bonding electrode 13 are in contact with each other, and the lid-side second bonding electrode 10 and the base-side second bonding electrode 12 are in contact with each other. Become. In this state, a predetermined temperature and a predetermined pressure are applied. Then, since the uppermost Au layers located at the boundaries of the

electrodes

9, 10, 12, and 13 that are in contact with each other diffuse into each other, the base substrate 2 and the lid substrate 3 are bonded. As a result, the space formed between the base substrate 2 and the lid substrate 3 is hermetically sealed while remaining in a vacuum state (formation of an airtight space). Finally, in this embodiment, the uppermost Au films of the lid-side first bonding electrode 9 and the base-side first bonding electrode 13 are diffusion-bonded to each other, thereby making it possible to obtain an airtight space.

When the pressure switch 1 in FIG. 1(a) is placed in a vacuum, the external pressure of the pressure switch 1 and the pressure of the airtight space formed between the base substrate 2 and the lid substrate 3 are the same, or the pressure switch 1 is placed under a vacuum. If the external pressure of 1 is negative pressure with respect to the air pressure of the airtight space formed between the base substrate 2 and the lid substrate 3, the diaphragm 5 expands outward (toward the recess 4 side), so that the lid substrate The lid-side movable contact electrode 8 on the diaphragm 5 side of No. 3 and the base-side fixed contact electrode 11 on the recess 7 (recess) side of the base substrate 2 are separated from each other and do not come into contact with each other. This results in an open loop (broken wire) and no current flows.

When the degree of vacuum in the space in which the pressure switch 1 in FIG. The pressure becomes higher than the atmospheric pressure, and the diaphragm 5 bends (warps) toward the recess 7 (recess) of the base substrate 2, causing the lid-side movable contact electrode 8 on the diaphragm 5 side of the lid substrate 3 and the recess 7 (recess) of the base substrate 2 to ) side makes contact with the base side fixed contact electrode 11. This creates a closed loop (short circuit) and allows current to flow.

Therefore, according to the first embodiment described above, since the diaphragm 5 is formed of crystal, the thickness can be controlled by measuring its resonance frequency. Thereby, it is possible to stably control the thickness of the diaphragm 5 with a balance between the strength of the diaphragm 5 and the sensitivity of the pressure switch 1, and it is possible to provide a high-quality pressure switch 1.

Furthermore, by using quartz as the diaphragm, a large number of pressure switches 1 can be manufactured at once using, for example, wet etching or photolithography techniques, and an inexpensive pressure switch 1 can be provided.

Furthermore, since the base substrate 2 and the lid substrate 3 are made of the same material (for example, crystal), it is possible to prevent stress caused by the difference in linear expansion coefficients when the two

substrates

2 and 3 are bonded. can.

Furthermore, if the base substrate 2 and the lid substrate 3 are formed to have the same thickness, when the base substrate 2 and the lid substrate 3 are bonded together, warping (the base substrate 2 (warping of the joined body of the lid substrate 3 and the lid substrate 3) can be suppressed.

In the lid substrate 3, the diaphragm 5 and the thick portion 6 around it are integrally formed, so even if the diaphragm 5 is formed thin, the mechanical strength of the diaphragm 5 can be maintained.

In addition, since the lid substrate 3 and the base substrate 2 are bonded by mutual diffusion of metal films, unintended gas may be released during the bonding process, for example, when both

substrates

2 and 3 are bonded with a conductive adhesive. can be prevented from occurring. Thereby, the pressure in the airtight space formed between the base substrate 2 and the lid substrate 3 can be easily controlled, and in turn, the operating pressure of the pressure switch 1 can be precisely controlled.

Furthermore, while the top layer of the lid-side movable contact electrode 8 of the pressure switch 1 is formed of Ti, the top layer of the base-side fixed contact electrode 11 is formed of Au. Since Au is a softer metal (metal with lower hardness) than Ti, for example, if the top layers of both

electrodes

8 and 11 are both made of Au, if the pressure switch 1 remains on for a long time, , the

electrodes

8 and 11 may come into close contact with each other and become difficult to separate. Therefore, by forming the top layer of the lid-side movable contact electrode 8 with a Ti film that has higher hardness than an Au film and is less likely to cause interdiffusion, both

electrodes

8 and 11 can be maintained even if the on state lasts for a long time. Since it is possible to make it difficult for the pressure switch to come into close contact with each other, it is possible to provide a pressure switch 1 that can be stably switched on and off.

Furthermore, diffusion bonding between metal films makes it easier to control the thickness of the bonded portion after bonding, compared to bonding using a metal brazing material. For example, in the case of joining using a metal brazing material, the thickness of the metal brazing material tends to vary, and the distance between the electrodes between both contacts tends to vary. However, in this diffusion bonding, it is difficult to cause variations in the distance between the electrodes between the two contacts, so that pressure detection accuracy can be improved. Furthermore, in this embodiment, the formation of the recess 4 of the lid substrate 3 and the recess 7 of the base substrate made of quartz is limited to one main surface side of each of the

substrates

2 and 3.

Contact electrodes

9 and 10 are formed on the main surface of the lid substrate 3 on the side where the recess 4 is not formed, that is, the side that is not thinned by wet etching. The surface of crystal tends to become rough due to wet etching, but in this embodiment, the

contact electrodes

9 and 10 are formed on the main surface that has not been wet-etched from one side. The distance between them becomes stable.

In addition, it is possible to adjust the air pressure inside the airtight space by the outside air pressure when airtightly sealing. For example, if the outside air pressure at the time of airtight sealing is 1000 Pascal, the air pressure inside the airtight space will be 1000 Pascal, With 1000 Pa as the threshold, if the external pressure is greater than 1000 Pa, the state shown in Figure 1(b) will occur and electricity will flow, and if the external pressure is less than 1000 Pa, the state shown in Figure 1(c) will occur and electricity will flow. will not flow. Therefore, it is possible to more appropriately test devices whose normal operation is guaranteed at an atmospheric pressure of 1000 Pascal or less.

<<Second embodiment>>
A pressure switch 1A according to a second embodiment of the present invention will be described with reference to FIG. 3. In the first embodiment, the fixed contact (base-side fixed contact electrode 11) is composed of one electrode film, whereas in the second embodiment, the fixed contact is composed of two divided electrode films. It consists of In addition, in the second embodiment, the same reference numerals as in the first embodiment are given to the parts having the same configuration as in the first embodiment, and the description thereof will be omitted.

The pressure switch 1A is configured to include a base substrate 2A and a lid substrate 3A disposed opposite to the base substrate 2A. For example, the same material as the base substrate 2 and lid substrate 3 of the first embodiment can be used as the material of the base substrate 2A and the lid substrate 3A.

The lid board 3A has a substantially rectangular shape in plan view when viewed from the upper side to the lower side in FIG. A recess 4A having a substantially circular shape in plan view is formed at approximately the center on the bottom surface of the lid substrate 3A (the surface opposite to the base substrate 2A when the pressure switch 1A is assembled). ), a depression 4B having a substantially circular shape in plan view is formed at substantially the center in plan view. The depression 4A and the depression 4B substantially overlap each other in a plan view (at substantially the same position in a plan view) and have substantially the same area in a plan view. A thin diaphragm 5A is formed in a portion that constitutes the bottom surface of this depression 4A and the bottom surface of the depression 4B. For example, the same thickness as the diaphragm 5 of the first embodiment can be used as the thickness of the diaphragm 5A (thickness in the vertical direction of the drawing).

In the lid substrate 3A, the peripheral portion of the thin diaphragm 5A formed on the lid substrate 3A in a plan view is thicker than the diaphragm 5A, and the thickness of the diaphragm 5A is thicker than that of the diaphragm 5A. The flesh portion (base portion) 6A is integrally molded from the same material.

A first bonding electrode 9A and a second bonding electrode 10A are formed in the thick portion 6A on the lower surface of the lid substrate 3A.

The base substrate 2A has a substantially rectangular shape in a plan view viewed from the upper side to the lower side in FIG. By joining the lid substrate 3A and the base substrate 2A, a movable contact electrode 8A forming a movable contact, which will be described later, and first and second electrodes forming a fixed contact, which will be described later, are placed in the recess 4B forming the lower surface of the diaphragm 5A. Two fixed contact electrodes 11A and 11B are arranged to form an airtight space in which the diaphragm 5A can be deformed.

On the lower surface of the diaphragm 5A formed on the lid substrate 3A (the surface facing the base substrate 2A when the pressure switch 1A is assembled), a movable contact electrode having a substantially circular shape in a plan view is provided approximately at the center in a plan view. 8A is provided. In the vacuum of FIG. 3(a), the movable contact electrode 8A is separated from other electrodes such as first and second fixed contact electrodes 11A and 11B on the base substrate 2A side, which will be described later, and does not come into contact with them. Under the atmospheric pressure of b), it comes into contact with each of a first fixed contact electrode 11A and a second fixed contact electrode 11B on the base substrate 2A side, which will be described later. The movable contact electrode 8A has the same film configuration as the lid side movable contact electrode 8 of the first embodiment, and includes a first Ti film, a first Au film, and a second Ti film in order from the diaphragm 5A side. The membranes are laminated. Further, the thickness of each metal film constituting the movable contact electrode 8A is the same as the thickness of each metal film constituting the lid-side movable contact electrode 8 of the first embodiment. The thickness of the first Ti film is 300 Å, the thickness of the first Au film one layer above it is 2000 Å, and the thickness of the second Ti film one layer above it is 300 Å.

As shown in FIG. 3(a), the upper surface of the base substrate 2A (the surface facing the lid substrate 3A when the pressure switch 1A is assembled) has a first fixed contact electrode which is a divided fixed contact electrode. An electrode 11A, a second fixed contact electrode 11B, a first bonding electrode 13A, and a second bonding electrode 12A are formed. The first fixed contact electrode 11A and the second fixed contact electrode 11B are both formed on the upper surface of the base substrate 2A in a region facing the diaphragm 5A formed on the lid substrate 3A. When the diaphragm 5A is not deformed, the first fixed contact electrode 11A, the second fixed contact electrode 11B, and the movable contact electrode 8A are opposed to each other with a predetermined interval apart. The contact/separation between the first fixed contact electrode 11A and the second fixed contact electrode 11B and the movable contact electrode 8A is switched.

For example, the first fixed contact electrode 11A and the second fixed contact electrode 11B are each formed in a semicircular shape, and are arranged at a predetermined interval. The first bonding electrode 13A is formed integrally with the first fixed contact electrode 11A, and is formed on the upper surface of the base substrate 2A in a region facing the thick portion 6A (base portion) of the lid substrate 3A. The second bonding electrode 12A is integrally formed with the second fixed contact electrode 11B, and is formed on the upper surface of the base substrate 2A in a region facing the thick portion 6A (base portion) of the lid substrate 3A. Note that the first fixed contact electrode 11A and the first bonding electrode 13A are not in contact with the second fixed contact electrode 11B and the second bonding electrode 12A.

The first bonding electrode 9A, the second bonding electrode 10A on the lid board 3A side, the first bonding electrode 13A, the second bonding electrode 12A, the first fixed contact electrode 11A, the second fixed contact on the base substrate 2A side The electrode 11B has the same film configuration as the base-side fixed contact electrode 11, the base-side first bonding electrode 13, and the base-side second bonding electrode 12 of the first embodiment, and is located on the upper surface of the base substrate 2A. A first Ti film, a first Au film, a second Ti film, and a second Au film are laminated in this order. The thickness of each metal film constituting the first fixed contact electrode 11A, the second fixed contact electrode 11B, the first bonding electrode 13A, and the second bonding electrode 12A is the same as that of the base side fixed contact of the first embodiment. The film thickness is the same as that of each metal film constituting the base electrode 11, the base-side first bonding electrode 13, and the base-side second bonding electrode 12. For example, the thickness of the first Ti film is 300 Å, The thickness of the first Au film one layer above it is 2000 Å, the thickness of the second Ti film one layer above it is 300 Å, and the thickness of the second Au film one layer above it is 1000 Å.

Note that in this embodiment, as in the first embodiment, the first bonding electrode 9A and the second bonding electrode 10A on the lid substrate 3A side and the first bonding electrode on the base substrate 2A side are finally connected. An airtight space is formed by diffusion bonding the uppermost Au films of each of the second bonding electrode 13A and the second bonding electrode 12A.

When the pressure switch 1A in FIG. 3(a) is placed in a vacuum, the external pressure of the pressure switch 1A and the pressure inside the airtight space formed between the base substrate 2A and the lid substrate 3A are almost the same. Yes, the diaphragm 5A does not deform, and the movable contact electrode 8A on the lid substrate 3A side and the first fixed contact electrode 11A and the second fixed contact electrode 11B on the base substrate 2A side are isolated and do not contact each other. . This results in an open loop (broken wire) and no current flows.

When the degree of vacuum in the space where the pressure switch 1A in FIG. The pressure becomes higher than the atmospheric pressure, and the diaphragm 5A bends (warps) toward the upper surface of the base substrate 2A, causing the movable contact electrode 8A on the diaphragm 5A side of the lid substrate 3A, and the first fixed contact electrode 11A and the first fixed contact electrode 11A on the base substrate 2A side. The two fixed contact electrodes 11B are in contact with each other. This creates a closed loop (short circuit) and allows current to flow.

According to this embodiment, the same effects as the first embodiment described above are achieved. Furthermore, compared to the first embodiment, the electrode film follows the diaphragm 5A more closely, and unexpected deformation of the diaphragm 5A due to film stress can be suppressed. In addition, the movable contact electrode 8A plays the role of electrically connecting the first fixed contact electrode 11A and the second fixed contact electrode 11B when the diaphragm 5A is bent due to a pressure change. There is no need to form an extraction electrode for electrical connection with. This solves the problem of electrode breakage (disconnection) and unstable connection when forming extraction electrodes in regions of different thicknesses of the lid substrate 3A (at the boundary between the recess and the thick part 6A). .

<<Third embodiment>>
A pressure switch 1B according to a third embodiment of the present invention will be described with reference to FIG. 4. In the second embodiment, the first fixed contact electrode 11A and the second fixed contact electrode 11B are formed on the base substrate 2A, whereas in the third embodiment, a diaphragm is also formed on the base substrate 2A side. 5B is formed, and a base-side first movable contact electrode 11C and a base-side second movable contact electrode 11D are arranged in place of the first fixed contact electrode 11A and the second fixed contact electrode 11B. There is. In addition, in the third embodiment, parts having the same configuration as those in the first embodiment or the second embodiment are given the same reference numerals as in the first embodiment or the second embodiment. omitted.

The base substrate 2B has a substantially rectangular shape in plan view when viewed from the upper side to the lower side in FIG. On the opposite surface), a depression 7A having a substantially circular shape in plan view is formed at substantially the center in plan view. The depression 7A and the depressions 4A and 4B on the lid substrate 3A side substantially overlap each other in plan view (located in substantially the same position in plan view) and have substantially the same area in plan view. A thin diaphragm 5B is formed in a portion constituting the bottom surface of this depression 7A.

The diaphragm 5B substantially overlaps the diaphragm 5A on the lid substrate 3A side (located at substantially the same position in the plan view) when viewed from the top to the bottom in FIG. 4, and has substantially the same area in the plan view. Diaphragms 5A and 5B are arranged facing each other. For example, the same thickness as the diaphragm 5 of the first embodiment can be used as the thickness of the diaphragm 5B (thickness in the vertical direction of the drawing).

In the base substrate 2B, the peripheral portion of the thin diaphragm 5B formed on the base substrate 2B in a plan view is thicker than the diaphragm 5B, and the thickness of the diaphragm 5B is thicker than that of the diaphragm 5B. The meat part (base part) 6B is integrally molded.

The upper surface of the diaphragm 5B formed on the base substrate 2B (the surface facing the lid substrate 3A when the pressure switch 1B is assembled) has a semicircular shape and a base-side first movable portion located a predetermined distance apart. A contact electrode 11C and a base-side second movable contact electrode 11D are provided. Under the vacuum of FIG. 4(a), the movable contact electrode 8A does not contact other electrodes such as the base-side first movable contact electrode 11C and the base-side second movable contact electrode 11D formed on the base substrate 2B. , comes into contact with each of the base-side first movable contact electrode 11C and the base-side second movable contact electrode 11D under atmospheric pressure as shown in FIG. 4(b). The base-side first movable contact electrode 11C and the base-side second movable contact electrode 11D have the same membrane configuration as the first fixed contact electrode 11A and the second fixed contact electrode 11B of the second embodiment. A first Ti film, a first Au film, a second Ti film, and a second Au film are laminated in this order from the upper surface side of the diaphragm 5A. The thickness of each metal film constituting the base-side first movable contact electrode 11C and the base-side second movable contact electrode 11D is the same as that of the first fixed contact electrode 11A and the second fixed contact electrode of the second embodiment. For example, the thickness of the first Ti film is 300 Å, the thickness of the first Au film one layer above it is 200 Å, and the thickness of the first Au film one layer above it is the same as that of each metal film constituting 11B. The thickness of the second Ti film is 300 Å, and the thickness of the second Au film one layer above it is 1000 Å.

The first bonding electrode 13B is integrally formed with the base-side first movable contact electrode 11C, and is an area (base portion) on the upper surface of the base substrate 2A that faces the thick portion 6A (base portion) of the lid substrate 3A. 6B). The second bonding electrode 12B is integrally formed with the base-side second movable contact electrode 11D, and is an area (base portion) on the upper surface of the base substrate 2A that faces the thick portion 6A (base portion) of the lid substrate 3A. 6B). Note that the first bonding electrode 13B and the base-side first movable contact electrode 11C are not in contact with the second bonding electrode 12B and the base-side second movable contact electrode 11D.

The first bonding electrode 13B and the second bonding electrode 12B both have the same film configuration as the first bonding electrode 13A and the second bonding electrode 12A of the second embodiment, and are located on the upper surface of the base substrate 2B. A first Ti film, a first Au film, a second Ti film, and a second Au film are laminated in order from the side. The film thickness of each metal film constituting the first bonding electrode 13B and the second bonding electrode 12B is the same as that of each metal film constituting the first bonding electrode 13A and the second bonding electrode 12A of the second embodiment. For example, the thickness of the first Ti film is 300 Å, the thickness of the first Au film one layer above it is 2000 Å, and the thickness of the second Ti film one layer above it is the same as the film thickness. The thickness is 300 Å, and the thickness of the second Au film one layer above it is 1000 Å.

The lid substrate 3A and the various electrodes 8A formed on the lid substrate 3A are the same as those in the second embodiment, so the description thereof will be omitted by giving them the same reference numerals.

Note that in this embodiment, as in the first embodiment, the first bonding electrode 9A and the second bonding electrode 10A on the lid substrate 3A side and the first bonding electrode on the base substrate 2B side are finally connected. An airtight space is formed by diffusion bonding the uppermost Au films of each of the second bonding electrode 13B and the second bonding electrode 12B.

When the pressure switch 1B in FIG. 4(a) is placed in a vacuum, the external pressure of the pressure switch 1B and the pressure in the airtight space formed between the base substrate 2B and the lid substrate 3A are almost the same. Yes, the diaphragm 5A on the lid substrate 3A side and the diaphragm 5B on the base substrate 2B side are not deformed, and the movable contact electrode 8A on the lid substrate 3A side and the base-side first movable contact electrode 11C on the base substrate 2B side. and the base-side second movable contact electrode 11D are isolated and do not contact each other. This results in an open loop (broken wire) and no current flows.

When the degree of vacuum in the space where the pressure switch 1B shown in FIG. The pressure becomes higher than the atmospheric pressure, and the diaphragm 5A on the lid substrate 3A side bends (warps) toward the diaphragm 5B on the base substrate 2B side, and the diaphragm 5B on the base substrate 2B side also bends (warps) toward the diaphragm 5A side on the lid substrate 3A. . Thereby, the movable contact electrode 8A on the diaphragm 5A side of the lid substrate 3A comes into contact with each of the base side first movable contact electrode 11C and the base side second movable contact electrode 11D on the base substrate 2B side. This creates a closed loop (short circuit) and allows current to flow.

According to this embodiment, the same effects as the first embodiment described above are achieved. Furthermore, the two diaphragms 5A, 5B can be deformed, and the two diaphragms 5A, 5B can come into contact with each other with a smaller amount of displacement, so that pressure can be detected more sensitively.

≪Fourth embodiment≫
A pressure switch 1C according to a fourth embodiment of the present invention will be described with reference to FIG. 5. In the second embodiment, divided fixed contacts (first and second fixed contact electrodes 11A, 11B) are arranged on the upper surface of the base substrate 2A, whereas in the fourth embodiment, the lid A cover substrate 30 is bonded to the upper surface of the substrate 3B, and divided fixed contact electrodes (first fixed contact electrode 11E, second fixed contact electrode 11F) are arranged on the lower surface of the cover substrate 30. Further, when the outside is in a vacuum state, the fixed contact electrodes 11E, 11F and the movable contact electrode 8B arranged on the diaphragm 5C come into contact, forming a closed loop (short circuit) and allowing current to flow. . In addition, in the fourth embodiment, parts having the same configuration as those in the first to third embodiments are designated by the same reference numerals as in the first to third embodiments. omitted.

The pressure switch 1C is configured to include a base substrate 2C, a lid substrate 3B disposed facing the base substrate 2C, and a cover substrate 30 disposed opposite the lid substrate 3B. For example, the same material as the base substrate 2 and lid substrate 3 of the first embodiment can be used as the material of the base substrate 2C and the lid substrate 3B. Similarly, the cover substrate 30 can be made of the same material (eg, crystal, glass) as the base substrate 2 of the first embodiment.

The lid board 3B has a substantially rectangular shape in plan view when viewed from the upper side to the lower side in FIG. ) is formed with a depression 4C (concavity) having a substantially circular shape in plan view, and a thin diaphragm 5C is formed at the bottom of the depression 4C.

In the lid substrate 3B, the peripheral portion of the thin diaphragm 5C formed on the lower surface of the lid substrate 3B in plan view is thicker than the diaphragm 5C, and is thicker than the diaphragm 5C and the diaphragm 5C. The thick wall portion 6C (hereinafter referred to as the "base portion" as appropriate) is integrally molded of the same material.

On the upper surface of the diaphragm 5C formed on the lid substrate 3B (the surface facing the cover substrate 30 when the pressure switch 1C is assembled), a movable contact electrode having a substantially circular shape in a plan view is provided approximately at the center in a plan view. 8B is provided. The movable contact electrode 8B contacts other electrodes such as first and second fixed contact electrodes 11E and 11F on the cover substrate 30 side, which will be described later, under the vacuum of FIG. Under atmospheric pressure, it does not come into contact with each of the first fixed contact electrode 11E and the second fixed contact electrode 11F on the cover substrate 30 side, which will be described later. The movable contact electrode 8B has the same film configuration as the lid side movable contact electrode 8 of the first embodiment, and includes a first Ti film, a first Au film, and a second Ti film in order from the diaphragm 5C side. The membranes are laminated. The thickness of each metal film constituting the movable contact electrode 8B is the same as the thickness of each metal film constituting the lid-side movable contact electrode 8 of the first embodiment. The thickness of the Ti film is 300 Å, the thickness of the first Au film one layer above it is 2000 Å, and the thickness of the second Ti film one layer above it is 300 Å.

In addition, as shown in FIG. 5(a), on the upper surface of the lid substrate 3B, a portion excluding the region where the diaphragm 5C is formed (a portion corresponding to the thick portion 6c) is provided with a lid-side first bonding electrode 9B. A lid-side second bonding electrode 10B is formed. The lid-side first bonding electrode 9B does not contact either the movable contact electrode 8B or the lid-side second bonding electrode 10B. Further, the lid-side second bonding electrode 10B does not contact either the movable contact electrode 8B or the lid-side first bonding electrode 9B. The first bonding electrode 9B on the lid side and the second bonding electrode 10B on the lid side include a first Ti film, a first Au film, a second Ti film, and a second Au film in order from the top surface of the lid substrate 3B. For example, the thickness of the first Ti film is 300 Å, the thickness of the first Au film one layer above it is 2000 Å, the thickness of the second Ti film one layer above it is 300 Å, The thickness of the second Au film, which is one layer above it, is 1000 Å.

On the lower surface of the lid substrate 3B (the surface facing the base substrate 2C when the pressure switch 1C is assembled), there is a lid-side third A bonding electrode 18 is formed. The lid-side third bonding electrode 18 includes a first Ti film, a first Au film, a second Ti film, and a second Au film stacked in this order from the bottom surface of the lid substrate 3B.

As shown in FIG. 5(a), the cover substrate 30 has a through-hole 21 that passes through the lid substrate 3B in a region that overlaps with the approximate center of the diaphragm 5C formed in the lid substrate 3B when the pressure switch 1C is assembled. It is formed. Thereby, the configuration is such that the air pressure outside the pressure switch 1C is applied to the diaphragm 5C.

On the lower surface of the cover substrate 30 (the surface facing the lid substrate 3B when the pressure switch 1C is assembled) are a first fixed contact electrode 11E and a second fixed contact electrode 11F, which are divided fixed contact electrodes. Then, a cover-side first bonding electrode 13C and a cover-side second bonding electrode 12C are formed. The first fixed contact electrode 11E and the second fixed contact electrode 11F are both located in a region on the lower surface of the cover substrate 30 that faces the diaphragm 5C formed on the lid substrate 3B, and are opposed to each other with the through hole 21 as a boundary. will be placed. For example, the first fixed contact electrode 11E and the second fixed contact electrode 11F are each formed in a semicircular shape.

The cover side first bonding electrode 13C is formed integrally with the first fixed contact electrode 11E, and is formed in a region on the lower surface of the cover substrate 30 facing the thick portion 6C of the lid substrate 3B. The cover-side second bonding electrode 12C is integrally formed with the second fixed contact electrode 11F, and is formed on the lower surface of the cover substrate 30 in a region facing the thick portion 6C of the lid substrate 3B. Note that the first fixed contact electrode 11E and the cover side first bonding electrode 13C are not in contact with and are not electrically connected to the second fixed contact electrode 11F and the cover side second bonding electrode 12C. . In addition, each of the first fixed contact electrode 11E and the second fixed contact electrode 11F is in contact with the movable contact electrode 8B arranged on the diaphragm 5C in a state where the diaphragm 5C is not deformed.

The first fixed contact electrode 11E, the second fixed contact electrode 11F, the cover side first bonding electrode 13C, and the cover side second bonding electrode 12C are all made of a first Ti film in order from the bottom surface of the cover substrate 30. , a first Au film, a second Ti film, and a second Au film are stacked. Also, for example, the thickness of the first Ti film is 300 Å, the thickness of the first Au film one layer above it is 2000 Å, the thickness of the second Ti film one layer above it is 300 Å, and one of the The thickness of the upper second Au film is 1000 Å.

On the upper surface of the cover substrate 30, a vertically long rectangular first external connection electrode 14c for external connection is formed at the right end, and a second vertically rectangular external connection electrode 14d is formed at the left end. Ru.

The cover substrate 30 includes a first interlayer connection conductor 15c that connects the first external connection electrode 14c formed on the top surface and the cover-side first bonding electrode 13C formed on the bottom surface, and a first interlayer connection conductor 15c formed on the top surface. A second interlayer connection conductor 15d is formed to connect the second external connection electrode 14d and the cover side second bonding electrode 12C formed on the lower surface.

The base substrate 2C has a substantially rectangular shape in a plan view viewed from the upper side to the lower side in FIG. By joining the lid substrate 3B and the base substrate 2C, an airtight space is formed that allows the diaphragm 5C formed on the lid substrate 3B to be deformed.

On the upper surface of the base substrate 2C (the surface facing the lid substrate 3B when the pressure switch 1C is assembled), a base-side bonding electrode 17 is formed at a location that comes into contact with the thick portion 6C of the lid substrate 3B. . The base-side bonding electrode 17 includes a first Ti film, a first Au film, a second Ti film, and a second Au film stacked in this order from the top surface of the base substrate 2C.

Note that in this embodiment, as in the first embodiment, the Au films of the uppermost layers of the lid-side third bonding electrode 18 and the base-side bonding electrode 17 are ultimately diffusion-bonded to each other. As a result, an airtight space is formed. In addition, the Au films of the uppermost layers of the first bonding electrode 9B on the lid side, the second bonding electrode 10B on the lid side, the first bonding electrode 13C on the cover side, and the second bonding electrode 12C on the cover side are diffusion bonded to each other. By doing so, the cover substrate 30 and the lid substrate 3B are joined.

When the pressure switch 1C in FIG. 5(a) is placed in a vacuum, the external pressure of the pressure switch 1C and the pressure in the airtight space formed between the base substrate 2C and the lid substrate 3B are almost the same. Yes, the diaphragm 5C on the lid substrate 3B side is not deformed, and the movable contact electrode 8B on the lid substrate 3B side and the first fixed contact electrode 11E and the second fixed contact electrode 11F on the cover substrate 30 side are Contact. This creates a closed loop (short circuit) and allows current to flow.

When the degree of vacuum in the space where the pressure switch 1C shown in FIG. The pressure becomes higher than the atmospheric pressure, and the diaphragm 5C on the lid substrate 3B side bends (warps) toward the base substrate 2C side. As a result, the movable contact electrode 8B on the diaphragm 5C side and the first fixed contact electrode 11E and second fixed contact electrode 11F on the cover substrate 30 side are separated from each other, resulting in an open loop (broken wire) and a current flow. will not flow.

According to this embodiment, the same effects as the first embodiment described above are achieved. Further, contrary to the first to third embodiments, it is possible to provide a pressure switch 1C that becomes a closed loop when placed under vacuum.

≪Fifth embodiment≫
A pressure switch 1D according to a fifth embodiment of the present invention will be described with reference to FIG. 6. The pressure switch 1D of the fifth embodiment is different from the pressure switch 1 of the first embodiment in that an upper substrate 40 is disposed on the upper surface 30a of the lid substrate 3. Note that, in the fifth embodiment, parts having the same configuration as those in the first embodiment are given the same reference numerals as in the first embodiment, and description thereof will be omitted.

The pressure switch 1D includes a base substrate 2, a lid substrate 3 whose lower surface 30b is arranged opposite to the upper surface 20a of the base substrate 2, and a top substrate whose lower surface 40b is arranged opposite to the upper surface 30a of the lid substrate 3. It is configured to include a plate substrate 40.

The upper substrate 40 has a substantially rectangular shape when viewed in plan from the upper side to the lower side in FIG. The upper substrate 40 is provided with a penetrating portion 40c in a region that overlaps with the recess 4 of the lid substrate 3 in a plan view of the upper substrate 40. By providing the penetration portion 40c in the region of the upper substrate 40, the air pressure in the space formed between the upper substrate 40 and the lid substrate 3 (the part of the recess 4 of the lid substrate 3) is maintained outside the pressure switch 1D. It will be the same as the atmospheric pressure.

On the upper surface of the thick part 6 constituting the lid substrate 3 (the surface facing the upper substrate 40 when the pressure switch 1D is assembled), almost the entire area that comes into contact with the upper substrate 40 is provided for lid side bonding. An electrode 41 is formed. In this embodiment, the lid-side bonding electrode 41 includes a first Ti film laminated on the upper surface of the thick portion 6, a first Au film laminated on the first Ti film, and a first Ti film laminated on the top surface of the thick portion 6. It is composed of a second Ti film laminated on the first Au film, and a second Au film laminated on the second Ti film. For example, the thickness of the first Ti film laminated on the upper surface 30a of the lid substrate 3 is 300 Å, the thickness of the first Au film one layer above it is 2000 Å, and the thickness of the second Ti film one layer above it is 300 Å. The film thickness is 300 Å, and the thickness of the second Au film one layer above it is 1000 Å. In this embodiment, each metal film is formed by sputtering, but other film forming methods such as vapor deposition can be used. Note that the metal forming the film corresponding to each Ti film is not limited to Ti, and may be, for example, Cr, Ni, W, Mo, or an alloy thereof.

On the lower surface 40b of the upper substrate 40 (the surface facing the lid substrate 3 when the pressure switch 1D is assembled), there is a bonding plate for upper plate side bonding over almost the entire area that contacts the thick part 6 of the lid substrate 3. An electrode 42 is formed. In this embodiment, the upper plate-side bonding electrode 42 includes a first Ti film laminated on the lower surface 40b of the upper substrate 40 and a first Au film laminated on the first Ti film. , a second Ti film laminated on the first Au film, and a second Au film laminated on the second Ti film. For example, the thickness of the first Ti film laminated on the lower surface 40b of the upper substrate 40 is 300 Å, the thickness of the first Au film one layer above it is 2000 Å, and the thickness of the second Ti film one layer above it is 300 Å. The thickness of the second Au film is 300 Å, and the thickness of the second Au film one layer above it is 1000 Å. In this embodiment, each metal film is formed by sputtering, but other film forming methods such as vapor deposition can be used. Note that the metal forming the film corresponding to each Ti film is not limited to Ti, and may be, for example, Cr, Ni, W, Mo, or an alloy thereof.

By diffusion bonding the top layer Au film configuring the lid side bonding electrode 41 and the top layer Au film configuring the top plate side bonding electrode 42 (Au-Au bonding), the top substrate 40 and The lid substrate 3 is joined. When bonding the lid substrate 3 and the upper substrate 40 using adhesive, there is a risk that the upper substrate 40 may be tilted with respect to the lid substrate 3, but in diffusion bonding, the upper substrate 40 may be tilted with respect to the lid substrate 3. 40 can be suppressed. It goes without saying that if the upper substrate 40 is allowed to tilt with respect to the lid substrate 3, the lid substrate 3 and the upper substrate 40 may be joined using an adhesive.

As the material of the upper substrate 40, it is preferable to use, for example, the same material as the lid substrate 3 (for example, crystal, glass). By making the upper substrate 40 and the lid substrate 3 of the same material, it is possible to eliminate the difference in thermal conductivity between the two, and to reduce the stress applied to the joint between the upper substrate 40 and the lid substrate 3. can.

When the pressure switch 1D in FIG. 6(a) is placed in a vacuum, the external pressure of the pressure switch 1D and the space formed between the upper substrate 40 and the lid substrate 3 (in the recess 4 of the lid substrate 3) The atmospheric pressure of the part) is the same. The air pressure in the recess 4 of the lid substrate 3 is the same as the air pressure in the airtight space formed between the base substrate 2 and the lid substrate 3, or the air pressure in the recess 4 of the lid substrate 3 is the same as that of the base substrate 2. If the pressure is negative with respect to the air pressure in the airtight space formed between the lid board 3 and the diaphragm 5, the diaphragm 5 expands outward (towards the recess 4), so the lid-side movable contact on the diaphragm 5 side of the lid board 3 The base-side fixed contact electrode 8 and the base-side fixed contact electrode 11 on the recess 7 (recessed portion) side of the base substrate 2 are separated from each other and do not come into contact with each other. This results in an open loop (broken wire) and no current flows.

When the degree of vacuum in the space in which the pressure switch 1D in FIG. 2 and the lid substrate 3, the diaphragm 5 bends (warps) toward the recess 7 of the base substrate 2, and the lid side movable contact on the diaphragm 5 side of the lid substrate 3 The electrode 8 and the base-side fixed contact electrode 11 on the recess 7 side of the base substrate 2 are in contact with each other. This creates a closed loop (short circuit) and allows current to flow.

According to this embodiment, the same effects as the first embodiment described above are achieved. Furthermore, the upper substrate 40 can protect the diaphragm 5 that constitutes the lid substrate 3, thereby preventing, for example, a situation in which the diaphragm 5 is damaged and the function of the pressure switch 1D as a switch is deteriorated. can.

Note that the arrangement of the upper substrate on the upper surface side of the lid substrate is applicable to, for example, the second embodiment, the third embodiment, the seventh embodiment, the eighth embodiment, etc.

≪Sixth embodiment≫
A pressure switch 1E according to a sixth embodiment of the present invention will be described with reference to FIG. 7. In the pressure switches 1 and 1D of the first and fifth embodiments, first and second external connection electrodes 14a and 14b for external connection are formed on the lower surface 20b of the base substrate 2. On the other hand, in the pressure switch 1E of the sixth embodiment, first and second external connection electrodes 46Ea and 46Eb for external connection are formed on the upper surface 40Ea of the upper substrate 40E. Note that, in the sixth embodiment, parts having the same configuration as those in the first or fifth embodiment are given the same reference numerals as in the first or fifth embodiment, and description thereof will be omitted.

The pressure switch 1E includes a base substrate 2E, a lid substrate 3E having a lower surface 30Eb facing the upper surface 20Ea of the base substrate 2E, and an upper substrate having a lower surface 40Eb facing the upper surface 30Ea of the lid substrate 3E. 40E. The same material as the base substrate 2 and the lid substrate 3 of the first and fifth embodiments can be used as the material of the base substrate 2E and the lid substrate 3E, and the upper substrate of the fifth embodiment can be used as the upper substrate 40E. The same material as 40 can be used.

The lid board 3E has a substantially rectangular shape in plan view when viewed from the top to the bottom in FIG. A depression 4 (concave portion) having a substantially circular shape in plan view is formed on the surface (opposite to the surface opposite to the surface opposite to the surface opposite to the surface) at substantially the center in plan view. As a result, the lid substrate 3E has a thin diaphragm 5 and a thick portion (base portion) 6E that is thicker than the thin diaphragm 5 around the thin diaphragm 5 in a plan view. In the lid substrate 3E, the diaphragm 5 and the thick portion 6E are integrally molded from the same material.

On the lower surface 30Eb of the lid substrate 3E, an electrode 8 for a lid-side movable contact forming a movable contact of the pressure switch 1E, which has the same shape and the same membrane structure as the first embodiment, and the lid-side movable contact electrode 8 are provided. The lid-side first bonding electrode 9 that is integrally formed and the lid-side second bonding electrode 10 that is not in contact with either the lid-side movable contact electrode 8 or the lid-side first bonding electrode 9 are integrated. It is formed.

On the upper surface of the thick wall portion 6E constituting the lid substrate 3E (the surface facing the upper substrate 40E when the pressure switch 1E is assembled), a lid-side first bonding An electrode 42Ea and a lid-side second bonding electrode 42Eb that is not in contact with the lid-side first bonding electrode 42Ea are formed. In this embodiment, the lid-side first bonding electrode 42Ea and the lid-side second bonding electrode 42Eb are formed by forming a first Ti film laminated on the upper surface of the thick portion 6E and a first Ti film, respectively. It is composed of a first Au film stacked on top, a second Ti film stacked on the first Au film, and a second Au film stacked on the second Ti film. ing. For example, the thickness of the first Ti film laminated on the upper surface of the thick portion 6E is 300 Å, the thickness of the first Au film one layer above it is 2000 Å, and the thickness of the second Ti film one layer above it is 300 Å. The film thickness is 300 Å, and the thickness of the second Au film one layer above it is 1000 Å. In this embodiment, each metal film is formed by sputtering, but other film forming methods such as vapor deposition can be used. Note that the metal forming the film corresponding to each Ti film is not limited to Ti, and may be, for example, Cr, Ni, W, Mo, or an alloy thereof.

The lid substrate 3E includes a lid-side first bonding electrode 42Ea formed on the upper surface of the thick portion 6E constituting the lid substrate 3E, and a lid-side first bonding electrode 9 formed on the bottom surface 30Eb of the lid substrate 3E. A first interlayer connection conductor 45Ea is formed to connect the two. The lid substrate 3E also includes a lid-side second bonding electrode 42Eb formed on the upper surface of the thick portion 6E constituting the lid substrate 3E, and a lid-side second bonding electrode 42Eb formed on the bottom surface 30Eb of the lid substrate 3E. A second interlayer connection conductor 45Eb that connects to the electrode 10 is formed. The first and second interlayer connection conductors 45Ea and 45Eb are each formed of, for example, a through hole whose inner wall surface is coated with a metal film. Note that the first and second interlayer connection conductors 45Ea and 45Eb may be formed using vias whose through holes are separately filled with a conductive material such as a metal paste.

The base substrate 2E has a substantially rectangular shape when viewed from the upper side to the lower side in FIG. A depression 7 (concave portion) having a substantially circular shape in plan view is formed in the substantially center portion in plan view.

On the upper surface 20Ea of the base substrate 2E, there are provided an electrode 11 for a base-side fixed contact that forms a fixed contact of the pressure switch 1E, which has the same shape and the same membrane structure as the first embodiment, and the base-side fixed contact electrode 11. The base-side second bonding electrode 12 integrally formed and the base-side first bonding electrode 13 that is not in contact with either the base-side fixed contact electrode 11 or the base-side second bonding electrode 12 are integrated. It is formed.

The lower surface 20Eb of the base substrate 2E has first and second external connection electrodes 14a and 14b for external connection formed on the lower surface 20b of the base substrate 2 of the first embodiment and the fifth embodiment. Corresponding first and second external connection electrodes for external connection are not formed. The base substrate 2E also has first and second interlayer connection conductors corresponding to the first and second interlayer connection conductors 15a and 15b formed on the base substrate 2 of the first embodiment and the fifth embodiment. No connecting conductor is formed.

The upper substrate 40E has a substantially rectangular shape in a plan view when viewed from the upper side to the lower side in FIG. 40c is provided.

On the lower surface 40Eb of the upper substrate 40E (the surface facing the lid substrate 3E when the pressure switch 1E is assembled), there is a first upper-plate-side joint at a location that abuts the upper surface of the thick portion 6E of the lid substrate 3E. and an upper plate side second bonding electrode 41Eb that does not contact the upper plate side first bonding electrode 41Ea. In this embodiment, the upper plate-side first bonding electrode 41Ea and the upper plate-side second bonding electrode 41Eb are connected to the first Ti film laminated on the lower surface 40Eb of the upper substrate 40E, and the first a first Au film laminated on the Ti film, a second Ti film laminated on the first Au film, and a second Au film laminated on the second Ti film. It consists of For example, the thickness of the first Ti film laminated on the lower surface 40Eb of the upper substrate 40E is 300 Å, the thickness of the first Au film one layer above it is 2000 Å, and the thickness of the second Ti film one layer above it is 300 Å. The thickness of the second Au film is 300 Å, and the thickness of the second Au film one layer above it is 1000 Å. In this embodiment, each metal film is formed by sputtering, but other film forming methods such as vapor deposition can be used. Note that the metal forming the film corresponding to each Ti film is not limited to Ti, and may be, for example, Cr, Ni, W, Mo, or an alloy thereof.

When the pressure switch 1E is assembled, in a plan view, the first bonding electrode 41Ea on the upper plate side and the first bonding electrode 42Ea on the lid side are in an overlapping position, and the second bonding electrode 41Eb on the upper plate side and the lid side are in an overlapping position. It is located in an overlapping position with the side second bonding electrode 42Eb. The uppermost Au film constituting the lid side first bonding electrode 42Ea and the uppermost Au film constituting the upper plate side first bonding electrode 41Ea are diffusion bonded (Au-Au bonding). By diffusion bonding (Au-Au bonding) the uppermost Au film constituting the second bonding electrode 42Eb and the uppermost Au film constituting the upper plate side second bonding electrode 41Eb, the upper substrate 40E and the lid substrate 3E are joined.

On the upper surface 40Ea of the upper substrate 40E, there is a first external connection electrode 46Ea for external connection that is vertically rectangular in plan view at the right end in plan view, and a left side in plan view that does not contact the first external connection electrode 46Ea. A second external connection electrode 46Eb having a vertically long rectangular shape in plan view is formed at the end. The first external connection electrode 46Ea and the second external connection electrode 46Eb are, for example, Ti film/Au film/Ti film/ A multilayer structure of Au films may also be used. Thereby, the first external connection electrode 46Ea and the second external connection electrode 46Eb can be formed simultaneously with the upper plate side first bonding electrode 41Ea and the upper plate side second bonding electrode 41Eb.

A first interlayer connection conductor 47Ea is formed on the upper substrate 40E to connect the first external connection electrode 46Ea formed on the upper surface 40Ea and the upper plate side first bonding electrode 41Ea formed on the lower surface 40Eb. There is. Further, a second interlayer connection conductor 47Eb is formed on the upper substrate 40E to connect the second external connection electrode 46Eb formed on the upper surface 40Ea and the upper plate side second bonding electrode 41Eb formed on the lower surface 40Eb. has been done. The first and second interlayer connection conductors 47Ea and 47Eb are each formed of, for example, a through hole whose inner wall surface is coated with a metal film. Note that the first and second interlayer connection conductors 47Ea and 47Eb may be formed using vias whose through holes are separately filled with a conductive material such as a metal paste.

The pressure switch 1E is fixed to a substrate S using an adhesive G such as a non-conductive adhesive, and a first external connection electrode 46Ea is connected to a first electrode 48a formed on the substrate S by a wire Wa. , a second external connection electrode 46Eb is connected to a second electrode 48b formed on the substrate S by a wire Wb.

When the pressure switch 1E in FIG. 7(a) is placed in a vacuum, the external pressure of the pressure switch 1E and the space formed between the upper substrate 40E and the lid substrate 3E (in the recess 4 of the lid substrate 3E) The atmospheric pressure of the part) is the same. The air pressure in the recess 4 of the lid board 3E is the same as the air pressure in the airtight space formed between the base board 2E and the lid board 3E, or the air pressure in the recess 4 of the lid board 3E is the same as that of the base board 2E. If the pressure is negative with respect to the air pressure in the airtight space formed between the lid board 3E and the diaphragm 5, the diaphragm 5 expands outward (towards the recess 4), so the lid-side movable contact on the diaphragm 5 side of the lid board 3E The base-side fixed contact electrode 8 and the base-side fixed contact electrode 11 on the side of the depression 7 (recessed portion) of the base substrate 2E are separated from each other and do not come into contact with each other. This results in an open loop (broken wire) and no current flows.

When the degree of vacuum in the space in which the pressure switch 1E in FIG. The pressure becomes higher than the air pressure in the airtight space formed between the lid board 3E and the lid board 3E, and the diaphragm 5 bends (warps) toward the recess 7 of the base board 2E, causing the lid side movable contact on the diaphragm 5 side of the lid board 3E to The electrode 8 and the base-side fixed contact electrode 11 on the recess 7 side of the base substrate 2 are in contact with each other. This creates a closed loop (short circuit) and allows current to flow.

According to this embodiment, the same effects as the above-described first embodiment and the same effects as the above-described fifth embodiment are achieved. Further, by mounting the pressure switch 1E on the substrate S by wire bonding, there is no need to use flux (soldering accelerator), and the fear of contaminating the surrounding area can be suppressed. Further, since the possibility of adhesive or the like interfering with the diaphragm 5 is reduced, malfunction of the pressure switch 1E can be avoided. Furthermore, by mounting the pressure switch 1E by wire bonding, even if the pressure switch 1E is a minute component, the first and second external connection electrodes 46Ea and 46Eb are reliably connected to the first and second electrodes 48a and 48b, respectively. can do. In addition, in the case of flip-chip mounting, there is a risk that large package distortion will occur because the pressure switch is fixed to the board at two or more different points. Wire bonding mounting is preferable to mounting.

Note that instead of arranging the first and second external connection electrodes for external connection on the lower surface of the base substrate, the first and second external connection electrodes for external connection are arranged on the upper surface of the upper substrate. , the second embodiment, the third embodiment, the seventh embodiment, the eighth embodiment, etc. can be applied after providing an upper substrate.

≪Seventh embodiment≫
A pressure switch 1F according to a seventh embodiment of the present invention will be described with reference to FIG. 8. The seventh embodiment relates to the details of the shapes of the base substrate 2F and lid substrate 3F of the pressure switch 1F. Note that in the seventh embodiment, the same reference numerals as in the first embodiment are given to parts having the same configuration as in the first embodiment, and the description thereof will be omitted.

The pressure switch 1F is configured to include a base substrate 2F and a lid substrate 3F whose lower surface 30Fb is arranged to face the upper surface 20Fa of the base substrate 2F. The same material as the base substrate 2 and lid substrate 3 of the first embodiment can be used as the material of the base substrate 2F and the lid substrate 3F, and in this embodiment, the base substrate 2F and the lid substrate 3F are AT Composed of cut crystals. The coordinate axes in FIG. 8 represent the crystal axes of AT-cut crystal, the X-axis is the electrical axis, the Y-axis is the mechanical axis, and the Z'-axis is the optical axis.

The lid board 3F has a substantially rectangular shape in plan view when viewed from the upper side to the lower side in FIG. A depression 4F (concave portion) having a substantially circular shape in plan view is formed on the surface opposite to the surface opposite to the surface opposite to the surface. As a result, the lid substrate 3F includes a thin diaphragm 5F and a thick portion (base portion) 6F that is thicker than the thin diaphragm 5F in a surrounding area of the thin diaphragm 5F in plan view. configured. In the lid substrate 3F, the diaphragm 5F and the thick portion 6F are integrally molded from the same material.

The depression 4F (concave portion) can be formed, for example, by wet etching the formation region of the depression 4F on the upper surface 30Fa of the lid substrate 3F using photolithography technology.

In the thick portion 6F related to the recess 4F formed by wet etching the formation region of the recess 4F on the upper surface 30Fa of the lid substrate 3F using photolithography technology, in the cross-sectional portion shown in the cross-sectional view in FIG. The outer side surface of the thick portion 6F is inclined so as to be located on the negative side of the Z' axis (to the right in FIG. 8) as it moves away from the upper surface of the thick portion 6F (angle of inclination≠90°). Further, in the cross-sectional area shown in FIG. 8, the inner side surface of the thick wall portion 6F is located on the negative direction side of the Z' axis (to the right side in FIG. 8) as it moves away from the top surface of the thick wall portion 6F. (angle of inclination ≠ 90°).

On the lower surface 30Fb of the lid substrate 3F, there are a lid-side movable contact electrode 8F that forms a movable contact of the pressure switch 1F, and a lid-side first bonding electrode 9F that is integrally formed with the lid-side movable contact electrode 8F. , a lid-side second bonding electrode 10F that is not in contact with either the lid-side movable contact electrode 8F or the lid-side first bonding electrode 9F is formed. For example, the lid side movable contact electrode 8F, the lid side first bonding electrode 9F, and the lid side second bonding electrode 10F are respectively the lid side movable contact electrode 8 and the lid side movable contact electrode 8F of the first embodiment. It has the same shape and the same membrane structure as the first bonding electrode 9 and the lid-side second bonding electrode 10.

The base substrate 2F has a substantially rectangular shape when viewed from the upper side to the lower side in FIG. A depression 7F (concave portion) having a substantially circular shape in plan view is formed in the substantially center portion of the surface (surface). In the base substrate 2F, a portion around the depression 7F formed on the upper surface 20Fa of the base substrate 2F in a plan view is thicker than a portion of the depression 7F. In the base substrate 2F, a portion (thin wall portion) 2Fa of the recess 7F and a portion (thick wall portion) 2Fb that is thicker than the thin wall portion 2Fa are integrally formed of the same material.

The depression 7F (concave portion) can be formed, for example, by wet etching the formation region of the depression 7F on the upper surface 20Fa of the base substrate 2F using photolithography technology.

In the recess 7F formed by wet etching the formation region of the recess 7F on the upper surface 20Fa of the base substrate 2F using photolithography technology, in the cross-sectional part shown in the cross-sectional view in FIG. The side surface is inclined (angle of inclination≠90°) so as to be located on the negative direction side of the Z' axis (right side in FIG. 8) as it moves away from the upper surface of the thick portion 2Fb. In addition, in the cross-sectional area shown in FIG. 8, the inner side surface of the thick wall portion 2Fb is located on the negative direction side of the Z' axis (to the right side in FIG. 8) as it moves away from the top surface of the thick wall portion 2Fb. (angle of inclination ≠ 90°).

On the upper surface 20Fa of the base substrate 2F, there are a base-side fixed contact electrode 11F that forms a fixed contact of the pressure switch 1F, and a base-side second bonding electrode 12F that is integrally formed with the base-side fixed contact electrode 11F. , a base-side first bonding electrode 13F that is not in contact with either the base-side fixed contact electrode 11F or the base-side second bonding electrode 12F is formed. In the cross section shown in FIG. 8, the electrode formed by integrally forming the base side fixed contact electrode 11F and the base side second bonding electrode 12F is connected to the upper surface of the thick part 2Fb of the base substrate 2F. It is bent at an obtuse angle at the boundary between the inner side surface of the base substrate 2Fb (the area surrounded by the dotted line RF1 in FIG. 8) is bent at an obtuse angle. For example, the shape of the base-side fixed contact electrode 11F, the base-side second bonding electrode 12F, and the base-side first bonding electrode 13F at the upper surface of the thick portion 2Fb and the upper surface of the thin portion 2Fa of the base substrate 2F is , the shapes of the base-side fixed contact electrode 11, the base-side second bonding electrode 12, and the base-side first bonding electrode 13 at the upper surface of the thick portion and the upper surface of the thin portion of the base substrate 2 are approximately the same. be. Further, for example, the base-side fixed contact electrode 11F has the same membrane configuration as the base-side fixed contact electrode 11 of the first embodiment, and the base-side second bonding electrode 12F has the same film configuration as the base-side fixed contact electrode 11 of the first embodiment. The base-side first bonding electrode 13F has the same film configuration as the base-side first bonding electrode 13 of the first embodiment.

In this embodiment, the first interlayer connection conductor 15a formed on the base substrate 2F connects the first external connection electrode 14a formed on the lower surface 20Fb and the base-side first bonding electrode 13F formed on the upper surface 20Fa. Connecting. Further, the second interlayer connection conductor 15b formed on the base substrate 2F connects the second external connection electrode 14b formed on the lower surface 20Fb and the base-side second bonding electrode 12F formed on the upper surface 20Fa.

In addition, in this embodiment, as in the first embodiment, the top layer of the Au film of the first bonding electrode 9F on the lid substrate 3F side and the first bonding electrode 13F on the base substrate 2F side are finally separated. The top layer Au film is diffusion bonded (Au-Au bond), and the top layer Au film of the second bonding electrode 10F on the lid substrate 3F side and the top layer of the second bonding electrode 12F on the base substrate 2F side are bonded. By diffusion bonding with the Au film (Au--Au bond), an airtight space is formed.

When the pressure switch 1F in FIG. 8(a) is placed in a vacuum, it becomes an open loop (broken wire) and no current flows, similar to the pressure switch 1 of the first embodiment. On the other hand, if the degree of vacuum in the space in which the pressure switch 1F in FIG. state.

According to this embodiment, the same effects as the first embodiment described above are achieved. Further, stress acting on the boundary between the diaphragm 5F and the thick portion 6F in the lid substrate 2F can be alleviated. Further, since the electrode formed by integrally forming the base-side fixed contact electrode 11F and the base-side second bonding electrode 12F has a gentle bend, it is difficult to break.

Note that the inclinations (tilt angle≠90°) of the outer and inner side surfaces of each substrate (base substrate, lid substrate) are different from those of each substrate (base substrate, lid substrate) in the second to sixth embodiments. (substrate, cover substrate, upper substrate, etc.).

≪Eighth embodiment≫
A pressure switch 1G according to an eighth embodiment of the present invention will be described with reference to FIG. 9. The lid substrate 3G of the pressure switch 1G of the eighth embodiment has a different shape from the lid substrate 3F of the pressure switch 1F of the seventh embodiment. Note that, in the eighth embodiment, parts having the same configuration as those in the first or seventh embodiment are given the same reference numerals as in the first or seventh embodiment, and description thereof will be omitted.

The pressure switch 1G is configured to include a base substrate 2F and a lid substrate 3G whose lower surface 30Gb is arranged to face the upper surface 20Fa of the base substrate 2F. The same material as the base substrate 2 and the lid substrate 3 of the first embodiment can be used as the material of the base substrate 2F and the lid substrate 3G, and in this embodiment, the base substrate 2F and the lid substrate 3G are made of AT Composed of cut crystals. The coordinate axes in FIG. 9 represent the crystal axes of AT-cut crystal, the X-axis is the electrical axis, the Y-axis is the mechanical axis, and the Z'-axis is the optical axis.

The lid board 3G has a substantially rectangular shape in plan view when viewed from the upper side to the lower side in FIG. A recess 4G (concave portion) is formed approximately at the center in a plan view on the surface opposite to the surface opposite to the surface. The recesses 4G are, in order from the upper surface 30Ga side of the lid substrate 3G, a second recess 4G2 formed on the upper surface 30Ga of the lid substrate 3G and having a substantially circular shape in plan view, and a second recess 4G2 formed on the bottom surface of the second recess 4G2 in plan view. The first depression 4G1 has a substantially circular shape and is smaller in size in plan view than the second depression 4G2.

Thereby, the lid substrate 3G is configured to include a thin diaphragm 5G and a thick portion 6G that is thicker than the thin diaphragm 5G around the thin diaphragm 5G in plan view. The thick wall portion 6G includes, in order from the outer side surface of the lid substrate 3G, a second thick wall portion 6G2 and a first thick wall portion 6G1 that is thinner than the second thick wall portion 6G2 and thicker than the diaphragm 5G. configured to include. In this way, the thickness of the thick portion 6G increases in two steps from the center side of the lid substrate 3G in plan view toward the outer side surface of the lid substrate 3G.

The depression 4G (concave portion) can be formed, for example, by wet etching the formation region of the depression 4G on the upper surface 30Ga of the lid substrate 3G using photolithography technology.

In the thick portion 6G related to the depression 4G formed by wet etching the formation region of the depression 4G on the upper surface 30Ga of the lid substrate 3G using photolithography technology, the thickness is The outer side surface of the second thick wall portion 6G2 constituting the wall portion 6G is inclined so as to be located on the negative direction side of the Z′ axis (to the right side in FIG. 9) as it moves away from the upper surface of the second thick wall portion 6G2. There is. In addition, in the cross section shown in FIG. 9, the inner side surface of the second thick part 6G2 constituting the thick part 6G moves in the negative direction of the Z' axis as it moves away from the upper surface of the second thick part 6G2. It is inclined so as to be located on the side (right side in FIG. 9). In addition, in the cross section shown in FIG. 9, the inner side surface of the first thick part 6G1 constituting the thick part 6G moves in the negative direction of the Z' axis as it moves away from the upper surface of the first thick part 6G1. It is inclined so as to be located on the side (right side in FIG. 9).

In the lid substrate 3G, the diaphragm 5G and the thick portion 6G including the first thick portion 6G1 and the second thick portion 6G2 are integrally molded from the same material.

On the lower surface 30Gb of the lid substrate 3G, a lid-side movable contact electrode 8G forming a movable contact of the pressure switch 1G, and a lid-side first bonding electrode 9G integrally formed with the lid-side movable contact electrode 8G. , a lid-side second bonding electrode 10G that is not in contact with either the lid-side movable contact electrode 8G or the lid-side first bonding electrode 9G is formed. For example, the lid-side movable contact electrode 8G has the same shape and the same membrane structure as the lid-side movable contact electrode 8 of the first embodiment, and the lid-side first bonding electrode 9G has the same shape and membrane structure as the lid-side movable contact electrode 8 of the first embodiment. It has the same shape and the same film structure as the first bonding electrode 9, and the lid-side second bonding electrode 10G has the same shape and the same film structure as the lid-side second bonding electrode 10 of the first embodiment. .

In addition, in this embodiment, as in the first embodiment, the top layer of the Au film of the first bonding electrode 9G on the lid substrate 3G side and the first bonding electrode 13F on the base substrate 2F side are finally separated. The top layer Au film is diffusion bonded (Au-Au bond), and the top layer Au film of the second bonding electrode 10G on the lid substrate 3G side and the top layer of the second bonding electrode 12F on the base substrate 2F side are bonded. By diffusion bonding with the Au film (Au--Au bond), an airtight space is formed.

When the pressure switch 1G in FIG. 9(a) is placed in a vacuum, it becomes an open loop (broken wire) and no current flows, similar to the pressure switch 1 of the first embodiment. On the other hand, when the degree of vacuum in the space in which the pressure switch 1G shown in FIG. state.

According to this embodiment, the same effects as the above-described first embodiment and the same effects as the above-described seventh embodiment are achieved. Further, the thick portion 6G may be configured to be a first thick portion 6G1 and a second thick portion 6G2 thicker than the first thick portion 6G1 in order from the diaphragm 5G side. The thickness of the lid substrate 3G is prevented from changing rapidly at the boundary portion where the 1-thick portion 6G1 and the diaphragm 5G are adjacent to each other. By doing so, stress on the boundary portion where the diaphragm 5G and the first thick portion 6G1 of the thick portion 6G are adjacent to each other can be alleviated.

Note that in the eighth embodiment, the thick portion 6G has a structure in which the thickness increases in two steps from the diaphragm 5G side toward the outer side surface of the lid substrate 3G, but the thick portion 6G is not limited to this. Alternatively, the thick portion may have a structure in which the thickness increases in three or more steps from the diaphragm side toward the outer side surface of the lid substrate.

Note that the content of increasing the thickness in multiple stages from the diaphragm side toward the outer side of the substrate (lid substrate) applies to substrates with diaphragms such as the second to sixth embodiments. It is possible.

(ratio of diaphragm diameter to thickness)
Next, a particularly preferable ratio of the diameter to the thickness of the diaphragm 5 of the pressure switch 1 will be explained with reference to FIG. Note that the particularly preferable ratio of the diameter to the thickness of the diaphragm 5 described below is applicable to the second to eighth embodiments and their modifications.

The diameter of the diaphragm 5, which is approximately circular in plan view from the top to the bottom of FIG. 10, which is a cross-sectional view of the diaphragm 5, is D, and the thickness of the diaphragm 5 (height in the vertical direction in the cross-sectional view shown in FIG. 10) is Let s) be t. In this example, the diameter D of the diaphragm 5 is set to 0.7 mm or more and 0.9 mm or less (0.7 mm≦D≦0.9 mm), and the thickness t is set to 5 μm or more and 10 μm or less (5 μm≦t≦10 μm). Set the diameter D and thickness t. Therefore, if the minimum value of the diameter D is written as Dmin and the maximum value as Dmax, and the minimum value of the thickness t is written as tmin and the maximum value as tmax, then D/t should be greater than or equal to Dmin/tmax and less than or equal to Dmax/tmin. The diameter D and thickness t of the diaphragm 5 are set as follows. In this example, Dmin/tmax=0.7/0.01=70 and Dmax/tmin=0.9/0.005=180, so D/t should be 70 or more and 180 or less ( 70≦D/t≦180), and the diameter D and thickness t of the diaphragm 5 are set.

If D/t is less than the lower limit value "70" (D/t<70), there is a possibility that the strength of the diaphragm 5 may become insufficient. Further, if D/t exceeds the upper limit value "180" (D/t>180), there is a possibility that the deformation of the diaphragm 5 in response to pressure becomes small and the pressure switch 1 will no longer function as a switch. On the other hand, if the diameter D and thickness t of the diaphragm 5 are set so that D/t is greater than or equal to the lower limit value "70" and less than or equal to the upper limit value "180" (70≦D/t≦180), as described above, It is possible to suppress the occurrence of problems.

(Concave shape when each substrate is made of glass)
Next, with reference to FIG. 11, the shapes of the

recesses

4 and 7 will be described when the base substrate 2 and lid substrate 3 of the pressure switch 1 according to the first embodiment are glass substrates. Note that each configuration is the same as in the first embodiment, so the explanation will be omitted by giving the same reference numerals.

If the crystal of the substrate is anisotropic, the amount of etching may be large in a particular direction, and if the substrate is formed of such a material, the shape of the diaphragm 5 will become unstable. On the other hand, since glass is an amorphous and isotropic material, when the base substrate 2 and lid substrate 3 are glass substrates and the

depressions

4 and 7 are formed by etching, the amount of etching (removal amount) becomes uniform regardless of direction. As a result, the

depressions

4 and 7 become approximately bowl-shaped as shown in FIG. 11, and the shape symmetry of the diaphragm 5 is improved.

In addition, since the

depressions

4 and 7 are bowl-shaped, the stress acting on the boundary between the thick part 6 and the diaphragm 5 is evenly distributed when the diaphragm 5 is deformed, so the pressure switch 1 has high durability. can be provided.

In addition, various design changes can be made to the configurations described in the first to eighth embodiments within the scope of the claims.

For example, each of the above-mentioned substrates may be made of a material containing Si and O as main components, such as crystal or glass, which is resistant to oxidation and has excellent environmental resistance.

Furthermore, the contents described in the first to eighth embodiments and the modifications of the first to eighth embodiments may be combined as appropriate.

≪Additional note 1≫
Supplementary Note 1, according to the first to eighth embodiments and the modifications of the first to eighth embodiments, is that the movable contact and the fixed contact or other The present invention relates to a pressure switch in which a movable contact contacts or separates.

Conventionally, there has been a pressure switch in which a movable contact and a fixed contact come into contact with or separate from each other by deforming a diaphragm due to external pressure changes, and for example, there is a pressure switch disclosed in Japanese Patent Application Laid-open No. 2001-176365.

In the pressure switch disclosed in Japanese Unexamined Patent Publication No. 2001-176365, a first substrate having a diaphragm that can be deformed by an external force and a second substrate are overlapped, and the first substrate and the second substrate are stacked on top of each other. A sealed space is formed between the device and the substrate, and a contact mechanism arranged within the sealed space is opened and closed based on the deformation of the diaphragm. In the contact mechanism, a movable contact is provided on the surface of the first substrate facing the second substrate at a position corresponding to the diaphragm, and a movable contact is provided on the surface of the second substrate facing the first substrate. A fixed contact is provided opposite to the diaphragm and comes into contact with the movable contact based on the deformation of the diaphragm. Silicon is used as a material constituting the first substrate having the diaphragm, and gold is used as a material constituting the movable contact provided on the surface of the first substrate facing the second substrate.

The pressure switch disclosed in Japanese Patent Application Laid-open No. 2001-176365 has a diaphragm formed by thinning a part of the silicon substrate, but there is a risk of damage due to repeated on/off switching, resulting in poor quality. A high pressure switch is required.

In view of the above-mentioned problems, the purpose of appendix 1 is to provide a high-quality pressure switch.

In order to achieve the above object, the pressure switch according to Supplementary Note 1 includes a first substrate and a second substrate that is bonded to the first substrate to form an airtight space between the first substrate and the second substrate. a diaphragm formed at a position corresponding to the airtight space and deformed by external pressure changes; and a diaphragm disposed on the diaphragm and movable. a first contact forming a contact; and a second contact facing the first contact at a predetermined distance and forming a fixed contact or another movable contact; The electrical connection is switched by the first contact and the second contact coming into contact with each other or being separated from each other, and the diaphragm is made of crystal.

According to this configuration, the diaphragm is formed of crystal. When the diaphragm is made thinner, the sensitivity as a pressure switch is improved, but the diaphragm lacks strength and is easily damaged. On the other hand, if the thickness of the diaphragm is increased, the strength can be ensured, but the sensitivity as a pressure switch will decrease. Therefore, in order to satisfy sensitivity and strength, it is necessary to keep the thickness of the diaphragm within a predetermined range. It is known that the thickness of crystal depends on the resonant frequency, and by controlling the resonant frequency of the diaphragm to a value corresponding to the desired thickness, a diaphragm with a desired thickness can be easily formed. Therefore, a high quality pressure switch with an optimized balance between strength and sensitivity can be formed. Further, by using crystal as the material for forming the diaphragm, a large number of pressure switches can be manufactured at once using, for example, wet etching or photolithography technology, and an inexpensive pressure switch can be provided.

Further, in order to achieve the above object, another pressure switch according to Supplementary Note 1 provides an airtight space between a first substrate and the first substrate by being joined to the first substrate. a second substrate to be formed, a diaphragm formed at a position corresponding to the airtight space and deformed by external pressure changes, and at least one of the first substrate and the second substrate; a first contact that is arranged to form a movable contact; and a second contact that faces the first contact at a predetermined distance and serves as a fixed contact or another movable contact, and the diaphragm is deformed. The electrical connection is switched by the first contact and the second contact coming into contact with each other or being separated from each other, and the diaphragm is made of glass.

According to Appendix 1, the diaphragm is formed of quartz. It is known that the thickness of crystal depends on the resonant frequency, and by controlling the resonant frequency of the diaphragm to a value corresponding to the desired thickness, a diaphragm with a desired thickness can be easily formed. Therefore, a high quality pressure switch with an optimized balance between strength and sensitivity can be formed.
Further, by using crystal as the material for forming the diaphragm, a large number of pressure switches can be manufactured at once using, for example, wet etching or photolithography technology, and an inexpensive pressure switch can be provided.

Supplementary Note 1 is widely applicable to various pressure switches that utilize deformation of a diaphragm.

≪Ninth embodiment≫
A pressure switch 1H according to a ninth embodiment of the present invention will be described with reference to FIGS. 12 and 13.

A pressure switch 1H according to a ninth embodiment of the present invention is a switch whose electrical connection is switched depending on a change in external pressure, and has a base substrate 2H and a lid substrate 3H, as shown in FIG. 12. The pressure switch 1H is placed, for example, in a closed space, and is used as a switch that detects whether airtightness within the closed space is ensured. The pressure switch 1H is connected to an IC having a determination function, and by determining the on/off state of the pressure switch 1H, the IC determines whether airtightness in the closed space is ensured.

The lid substrate 3H is made of AT-cut crystal. The upper surface 30Ha and lower surface 30Hb of the lid substrate 3H are mirror-finished (polished), and their flatness (TTV) is, for example, 0.15 μm or less. Note that AT-cut crystal is used as the material for the lid substrate 3H, but the material is not limited to this, and cut crystals whose resonance frequency depends on the thickness, such as BT-cut crystal and SC-cut crystal, may be used. You may also use Note that in each of the ninth to sixteenth embodiments, crystal is used as the material for each substrate, but the material is not limited to this, and for example, glass may be used. . When glass is used, a diaphragm with excellent shape symmetry can be formed.

The lid substrate 3H has a substantially rectangular shape in a plan view when viewed from the upper side to the lower side in FIG. A depression 4H (recess) having a substantially circular shape in plan view is formed in the center of the surface (opposite surface), and a thin diaphragm 5H is formed in a portion constituting the bottom of the depression 4H. ing. The depression 4H can be formed, for example, by wet etching the formation region of the depression 4H on the upper surface 30Ha of the lid substrate 3H using a photolithography technique.

The thickness of the diaphragm 5H (the thickness in the vertical direction in the drawing) is such that it can be relatively easily deformed in the thickness direction (in the vertical direction in the drawing) by external pressure, and the diaphragm 5H is not easily damaged. If yes, it is preferably 5 μm or more and 15 μm or less, more preferably 8 μm or more and 10 μm or less.

In the lid substrate 3H, the peripheral portion of the thin diaphragm 5H formed on the lid substrate 3H in a plan view is thicker than the diaphragm 5H, and the thickness of the diaphragm 5H is thicker than that of the diaphragm 5H. The flesh portion 6H (hereinafter appropriately referred to as "base portion") is integrally molded from the same material.

For example, in this embodiment, the thickness of the lid substrate 3H (thickness of the base portion 6H) is approximately 40 μm, whereas the thickness of the diaphragm 5H is approximately 10 μm. Note that there is a correlation between the thickness of the crystal substrate and its resonant frequency; for example, when the thickness of the substrate is t [mm] and the resonant frequency is F [kHz], the relationship F=1670/t holds true. Therefore, after forming the diaphragm 5H, the thickness of the manufactured diaphragm 5H can be estimated by measuring the resonance frequency.

The base substrate 2H is made of AT-cut crystal. Note that although AT-cut crystal is used as the material for the base substrate 2H, it is not limited to this, and BT-cut crystal, SC-cut crystal, etc. may also be used. Note that in each of the ninth to sixteenth embodiments, crystal is used as the material for each substrate, but the material is not limited to this, and for example, glass may be used. . Note that it is preferable that the lid substrate 3H and the base substrate 2H be formed of the same material.

The base substrate 2H has a substantially rectangular shape in plan view when viewed from the upper side to the lower side in FIG. A depression 7H (concave portion) having a substantially circular shape in plan view is formed in the substantially center portion of the surface. This depression 7H is located at a position facing the diaphragm 5H formed on the lid substrate 3H when the pressure switch 1H is assembled, and by joining the lid substrate 3H and the base substrate 2H as described later, A lid-side movable contact electrode 8H forming a movable contact to be described later and a base-side fixed contact electrode 11H forming a fixed contact to be described later are arranged to form an airtight space in which the diaphragm 5H can be deformed. Note that the depression 7H can also be formed by, for example, wet etching the formation region of the depression 7H on the upper surface 20Ha of the base substrate 2H using photolithography technology.

In the base substrate 2H, the surrounding area of the depression 7H formed on the upper surface of the base substrate 2H in plan view is thicker than the area of the depression 7H, and the area of the depression 7H and the area of the depression 7H are thicker than the area of the depression 7H. The thick wall portion is integrally molded from the same material.

In this embodiment, the thickness of the base substrate 2H (thickness of the thick portion of the base substrate 2H) is approximately 40 μm, which is the same as the thickness of the lid substrate 3H (thickness of the base portion 6H). The depth of the depression 7H (concave portion) of the base substrate 2H is 0.5 μm. As a result, if the diaphragm 5H is not deformed in a state where the lid substrate 3H and the base substrate 2H are joined, the lid side movable contact electrode 8H formed on the diaphragm 5H side and the base substrate The base side fixed contact electrode 11H formed on the 2H side is separated from the base side fixed contact electrode 11H.

Next, each electrode formed on the lid substrate 3H and the base substrate 2H will be explained with reference to FIG. 13. FIG. 13 is a diagram for explaining various electrodes, (a) is a diagram when viewed directly from the bottom surface of the lid substrate 3H, and (b) is a diagram when viewed from directly against the top surface of the base substrate 2H. (c) shows a view when viewed directly from the bottom surface of the base substrate 2H.

On the lower surface 30Hb of the lid substrate 3H, there are lid-side movable contact electrodes 8H, each of which is an electrode film, forming a movable contact of the pressure switch 1H, and a lid-side movable contact electrode 8H formed integrally with the lid-side movable contact electrode 8H. A first bonding electrode 9H and a lid-side second bonding electrode 10H that is not in contact with either the lid-side movable contact electrode 8H or the lid-side first bonding electrode 9H are formed.

As shown in FIG. 13(a), in this embodiment, the lid-side second bonding electrode 10H has a shape in which the right side of a vertically long rectangle is cut out in an arc shape, and the lower surface 30H of the lid substrate 3H , it is formed in a region corresponding to the thick portion 6H and on the left side of the region where the circular diaphragm 5H is formed.

The lid-side first bonding electrode 9H is formed to cover substantially all of the portion of the lower surface 30Hb of the lid substrate 3H where the lid-side second bonding electrode 10H is not formed in the area corresponding to the thick portion 6H. They are formed at predetermined intervals so as not to contact the lid-side second bonding electrode 10H.

As shown in FIG. 13(a), the lid-side movable contact electrode 8H is formed to extend from the end of the lid-side first bonding electrode 9H on the side closer to the diaphragm 5H toward the center of the diaphragm 5H. By doing so, it is arranged in the formation region (thin wall portion) of the diaphragm 5H.

The lid side first bonding electrode 9H, the lid side second bonding electrode 10H, and the lid side movable contact electrode 8H are connected to the first Ti film laminated on the lower surface 30Hb of the lid substrate 3H, and the first Ti film laminated on the lower surface 30Hb of the lid substrate 3H, respectively. a first Au film laminated on the Ti film, a second Ti film laminated on the first Au film, and a second Au film laminated on the second Ti film. It consists of However, regarding the lid-side movable contact electrode 8H, the uppermost second Au film is removed by etching, and the uppermost layer is made of a second Ti film. For example, the thickness of the first Ti film laminated on the lower surface 30Hb of the lid substrate 3H is 300 Å, the thickness of the first Au film one layer above it is 2000 Å, and the thickness of the second Ti film one layer above it is 300 Å. The film thickness is 300 Å, and the thickness of the second Au film one layer above it is 1000 Å. Note that in this embodiment, each metal film is formed by sputtering at a high temperature (for example, 150 to 200 degrees), but other film forming methods such as vapor deposition can be used.

Note that among the metal films, the main conductive film is the Au film, but the Au film has relatively low adhesion strength to the lid substrate 3H made of crystal. Therefore, a Ti film having relatively high adhesion strength to the lid substrate 3H is formed as a base metal film on the lower surface 30Hb of the lid substrate 3H. Since Au films tend to come into close contact with each other, if the top layer of the lid-side movable contact electrode 8H and the top layer of the base-side fixed contact electrode 11H are both Au films, for example, When they come into contact, there is a risk that they will come into close contact with each other and be unable to separate. In order to prevent this, the metals constituting the top layers of the lid side movable contact electrode 8H and the base side fixed contact electrode 11H are made of Au on one side and Ti on the other side. Note that the metal forming the film corresponding to each Ti film is not limited to Ti, and may be, for example, Cr, Ni, W, Mo, or an alloy thereof.

As shown in FIG. 12, on the upper surface 5Ha of the diaphragm 5H of the lid substrate 3H, a facing metal film 8aH that pairs with the lid-side movable contact electrode 8H is formed. The opposing metal film 8aH has the same structure and the same thickness as the lid-side movable contact electrode 8H (the thickness in the vertical direction in FIG. 12(a) is the same). They have the same film configuration, and the film thickness of each metal film is the same as the film thickness of the corresponding metal film of the lid side movable contact electrode 8H. In this embodiment, the opposing metal film 8aH includes a first Ti film stacked on the upper surface 5Ha of the diaphragm 5H, a first Au film stacked on the first Ti film, and a first Au film stacked on the first Ti film. The first Ti film is 300 Å thick, and the first Au film that is one layer above it is 2000 Å thick. The thickness of the upper second Ti film is 300 Å. However, the opposing metal film 8aH includes a first Ti film on the upper surface 5Ha of the diaphragm 5H, a first Au film on the first Ti film, a second Ti film on the first Au film, and a second Ti film on the first Au film. After laminating the second Au film on the second Ti film, the uppermost second Au film is removed by etching. Note that in this embodiment, each metal film is formed by sputtering at a high temperature (for example, 150 to 200 degrees), but other film forming methods such as vapor deposition can be used.

In addition, the opposing metal film 8aH substantially overlaps the lid-side movable contact electrode 8H (at approximately the same position as the lid-side movable contact electrode 8H) in a plan view from the upper side to the lower side in FIG. 12(a). ), and is formed to have approximately the same area as the lid-side movable contact electrode 8H.

Further, the opposing metal film 8aH is not in contact with other metal films and is electrically independent.

On the upper surface 20Ha of the base substrate 2, there are a base-side fixed contact electrode 11H, each of which is an electrode film, forming a fixed contact of the pressure switch 1H, and a base-side second electrode formed integrally with the fixed contact electrode 11H. A bonding electrode 12H and a base-side first bonding electrode 13H that is not in contact with either the base-side fixed contact electrode 11H or the base-side second bonding electrode 12H are formed.

As shown in FIG. 13(b), in this embodiment, the base-side second bonding electrode 12H has a shape like a vertically long rectangle with the right side cut out in an arc shape, and the upper surface 20Ha of the base substrate 2H , it is formed adjacent to the region on the left side of the region where the circular depression 7H (concave portion) is formed.

The base-side first bonding electrode 13H is formed to cover substantially all of the area where the depression 7H (recess) is formed and the portion where the base-side second bonding electrode 12H is not formed on the upper surface 20Ha of the base substrate 2H. They are formed at predetermined intervals so as not to contact the base-side second bonding electrode 12H.

As shown in FIG. 13(b), the base-side fixed contact electrode 11H extends from the end of the base-side second bonding electrode 12H closer to the recess 7H (recess) toward the center of the recess 7H (recess). formed to extend. Specifically, the base-side fixed contact electrode 11H extends from the end of the base-side second bonding electrode 12H to the side wall of the recess 7H (recess) and further to the center of the bottom of the recess 7H (recess). exists and is formed. Since the recess 7H (concave portion) is provided at a position facing the diaphragm 5H, when the diaphragm 5H is not deformed, the base side fixed contact electrode 11H and the lid side movable contact electrode 8H are separated by a predetermined interval. They face each other, and the contact/separation between the base-side fixed contact electrode 11H and the lid-side movable contact electrode 8H is switched by deformation of the diaphragm 5H.

The base-side first bonding electrode 13H, the base-side second bonding electrode 12H, and the base-side fixed contact electrode 11H are all made of a first Ti film laminated on the upper surface 20Ha of the base substrate 2H, a first Au film laminated on the Ti film, a second Ti film laminated on the first Au film, and a second Au film laminated on the second Ti film. It consists of However, in the base side fixed contact electrode 11H, unlike the lid side movable contact electrode 8H, the second Au film at the top layer is not removed by etching, and the top layer is composed of the second Au film. . For example, the thickness of the first Ti film stacked on the upper surface 20Ha of the base substrate 2H is 300 Å, the thickness of the first Au film one layer above it is 2000 Å, and the thickness of the second Ti film one layer above it is 300 Å. The film thickness is 300 Å, and the thickness of the second Au film one layer above it is 1000 Å. In this embodiment, each metal film is formed by sputtering at a high temperature (for example, 150 to 200 degrees), but other film forming methods such as vapor deposition can be used. Note that the metal forming the film corresponding to each Ti film is not limited to Ti, and may be, for example, Cr, Ni, W, Mo, or an alloy thereof. Further, the base side fixed contact electrode 11H is composed of a first Ti film laminated on the upper surface 20Ha of the base substrate 2H, and a first Au film laminated on the first Ti film. (It is composed of a base metal layer (first Ti film) and a single metal layer (first Au film) on the base metal layer (first Ti film)). In addition, the film structure of the lid side movable contact electrode 8H is replaced with the film structure of the base side fixed contact electrode 11H, and the film structure of the base side fixed contact electrode 11H is replaced with the film structure of the lid side movable contact electrode 8H. It may be replaced with the configuration.

As shown in FIG. 13(c), on the lower surface 20Hb of the base substrate 2H, there is a first external connection electrode 14Ha having a vertically long rectangular shape for external connection at the right end, and a first external connection electrode 14Ha having a vertically long rectangular shape for external connection at the left end. A second external connection electrode 14Hb is formed. The first external connection electrode 14Ha and the second external connection electrode 14Hb are each connected to a predetermined land electrode formed on the mounting surface of another substrate on which the pressure switch 1H is mounted. The predetermined land electrode and a predetermined terminal of an IC mounted on the other board are connected via a wiring electrode formed on the other board.

Note that the first external connection electrode 14Ha and the second external connection electrode 14Hb and the land electrode of the other substrate can be bonded, for example, with a conductive adhesive. Alternatively, metal bumps such as Au bumps may be formed on the first external connection electrode 14Ha and the second external connection electrode 14Hb, and they may be joined by ultrasonic bonding. Further, the top surface 30Ha of the lid substrate 3H and the mounting surface of another substrate are arranged so as to face each other and fixed with a non-conductive adhesive or the like, and the first external connection electrode 14Ha and the second external connection electrode 14Hb are connected to each other. It may also be connected to a predetermined land electrode by wire bonding.

The first external connection electrode 14Ha and the second external connection electrode 14Hb are, for example, Ti film/ A multilayer structure of Au film/Ti film/Au film may be used. Thereby, the base-side first bonding electrode 13H, the base-side second bonding electrode 12H, and the base-side fixed contact electrode 11H can be formed simultaneously.

The base substrate 2H includes a first interlayer connection conductor 15Ha that connects the first external connection electrode 14Ha formed on the bottom surface 20Hb and the base-side first bonding electrode 13H formed on the top surface 20Ha, and a first interlayer connection conductor 15Ha formed on the bottom surface 20Hb. A second interlayer connection conductor 15Hb is formed to connect the second external connection electrode 14Hb and the base-side second bonding electrode 12H formed on the upper surface 20Ha. The first and second interlayer connection conductors 15Ha and 15Hb are each formed of, for example, a through hole whose inner wall surface is coated with a metal film. As a manufacturing method, for example, a through hole is formed at a predetermined location of the base substrate 2H, and then the first external connection electrode 14Ha, the second external connection electrode 14Hb, the base side first bonding electrode 13H, and the base side second bonding are formed. When forming the electrode 12H for the base side and the electrode 11H for the base side fixed contact, a metal film having the same structure can be formed on the inner wall surface of the through hole as well. Note that the first and second interlayer connection conductors 15Ha and 15Hb may be formed using vias whose through holes are separately filled with a conductive material such as metal paste.

The base substrate 2H and the lid substrate 3H are bonded to each other by a lid-side first bonding electrode 9H and a lid-side second bonding electrode 10H formed on the bottom surface 30Hb of the lid substrate 3H and the top surface 20a of the base substrate 2. The bonding is performed by joining the base-side first bonding electrode 13H and the base-side second bonding electrode 12H. Specifically, the lid substrate 3H is laminated on the base substrate 2H under vacuum. At this time, the lid side first bonding electrode 9H and the base side first bonding electrode 13H are in contact with each other, and the lid side second bonding electrode 10H and the base side second bonding electrode 12H are in contact with each other. Become. In this state, a predetermined temperature and a predetermined pressure are applied. Then, since the Au in the uppermost layer located at the boundaries of the

electrodes

9H, 10H, 12H, and 13H that are in contact with each other is interdiffused, the base substrate 2H and the lid substrate 3H are bonded. Thereby, the space formed between the base substrate 2H and the lid substrate 3H is hermetically sealed while remaining in a vacuum state (formation of an airtight space). Finally, in this embodiment, the uppermost Au films of the lid-side first bonding electrode 9H and the base-side first bonding electrode 13H are diffusion-bonded to each other, thereby making it possible to obtain an airtight space.

When the pressure switch 1H in FIG. 12(a) is placed in a vacuum, the external pressure of the pressure switch 1H and the air pressure of the airtight space formed between the base substrate 2H and the lid substrate 3H are the same, or the pressure switch 1H is placed under a vacuum. If the external pressure at 1H is negative with respect to the air pressure in the airtight space formed between the base substrate 2H and the lid substrate 3H, the diaphragm 5H expands outward (toward the recess 4H), so the lid substrate The lid-side movable contact electrode 8H on the diaphragm 5H side of 3H and the base-side fixed contact electrode 11H on the recess 7H (recess) side of the base substrate 2 are separated and do not contact. This results in an open loop (broken wire) and no current flows.

When the degree of vacuum in the space in which the pressure switch 1H shown in FIG. The pressure becomes higher than the atmospheric pressure, and the diaphragm 5H bends (warps) toward the recess 7H (recess) of the base substrate 2H, causing the lid-side movable contact electrode 8H on the diaphragm 5H side of the lid substrate 3H to ) side makes contact with the base side fixed contact electrode 11H. This creates a closed loop (short circuit) and allows current to flow.

Therefore, according to the ninth embodiment described above, since the diaphragm 5H is formed of crystal, the thickness can be controlled by measuring its resonance frequency. Thereby, the thickness of the diaphragm 5H and the sensitivity of the pressure switch 1H can be stably controlled in a well-balanced manner, and a high-quality pressure switch 1H can be provided.

Furthermore, by using quartz as the diaphragm 5H, a large number of pressure switches 1H can be manufactured at once using, for example, wet etching or photolithography techniques, and an inexpensive pressure switch 1H can be provided.

Furthermore, since the base substrate 2H and the lid substrate 3H are made of the same material (for example, crystal), it is possible to prevent stress caused by the difference in linear expansion coefficients when the two substrates 2H and 3H are bonded. can.

In addition, when the base substrate 2H and the lid substrate 3H are formed to have the same thickness, when the base substrate 2H and the lid substrate 3H are bonded together, warpage (base substrate 2H (warping of the joined body between the lid substrate 3H and the lid substrate 3H) can be suppressed.

Furthermore, in the lid substrate 3H, the diaphragm 5H and the surrounding thick wall portion 6H are integrally formed, so even if the diaphragm 5H is formed thin, the mechanical strength of the diaphragm 5H can be maintained. .

In addition, since the lid substrate 3H and the base substrate 2H are bonded by mutual diffusion of metal films, unintended gas may be released during the bonding process, for example, when both substrates 2H and 3H are bonded with a conductive adhesive. can be prevented from occurring. Thereby, the pressure in the airtight space formed between the base substrate 2H and the lid substrate 3H can be easily controlled, and in turn, the operating pressure of the pressure switch 1H can be precisely controlled.

Furthermore, the top layer of the lid side movable contact electrode 8H of the pressure switch 1H is formed of Ti, whereas the top layer of the base side fixed contact electrode 11H is formed of Au. Since Au is a softer metal (metal with lower hardness) than Ti, for example, if the top layers of both electrodes 8H and 11H are both made of Au, if the pressure switch 1H remains on for a long time, , the electrodes 8H and 11H may come into close contact with each other and become difficult to separate. Therefore, by forming the top layer of the lid-side movable contact electrode 8H with a Ti film that has higher hardness than an Au film and is less likely to cause interdiffusion, both electrodes 8H and 11H are Since it is possible to make it difficult to make close contact, it is possible to provide a pressure switch 1H that can be stably switched between on and off.

Furthermore, diffusion bonding between metal films makes it easier to control the thickness of the bonded portion after bonding, compared to bonding using a metal brazing material. For example, in the case of joining using a metal brazing material, the thickness of the metal brazing material tends to vary, and the distance between the electrodes between both contacts tends to vary. However, in this diffusion bonding, it is difficult to cause variations in the distance between the electrodes between the two contacts, so that pressure detection accuracy can be improved. Furthermore, in this embodiment, the formation of the recess 4H of the lid substrate 3H made of crystal and the recess 7H of the base substrate 2H is limited to one main surface side of each substrate 2H, 3H. Contact electrodes 9H and 10H are formed on the main surface of the lid substrate 3H on the side where the recess 4H is not formed, that is, the side that has not been thinned by wet etching. The surface of crystal tends to become rough due to wet etching, but in this embodiment, the contact electrodes 9H and 10H are formed on the main surface that has not been wet etched from one side. The distance between them becomes stable.

In addition, by forming the lid-side movable contact electrode 8H on the lower surface of the diaphragm 5H and forming the opposing metal film 8aH on the upper surface of the diaphragm 5H, the thermal expansion coefficient of the diaphragm 5H and the thermal expansion of the lid-side movable contact electrode 8H are changed. The stress generated between the diaphragm 5H and the lid-side movable contact electrode 8H based on the difference in coefficient of thermal expansion between the diaphragm 5H and the opposing metal film based on the difference between the thermal expansion coefficient of the diaphragm 5H and the opposing metal film 8aH. This can be offset by the stress generated between the film 8aH and the film 8aH. This makes it possible to suppress warping (bending) of the diaphragm 5H in a state where no external pressure is applied to the pressure switch 1H at room temperature.

In addition, by making the lid-side movable contact electrode 8H and the opposing metal film 8aH have the same film configuration, the difference between the thermal expansion coefficient of the diaphragm 5H and that of the lid-side movable contact electrode 8H, and the thermal expansion of the diaphragm 5H. By making the difference between the thermal expansion coefficient and the thermal expansion coefficient of the opposing metal film 8aH the same, it is possible to improve the balance between the stress generated on the lower surface side of the diaphragm 5H and the stress generated on the upper surface side of the diaphragm 5H. In a state where no external pressure is applied to the pressure switch 1H, warpage (bending) of the diaphragm 5H can be more effectively suppressed.

In addition, by increasing the symmetry between the lid side movable contact electrode 8H and the opposing metal film 8aH by making the lid side movable contact electrode 8H and the opposing metal film 8aH have the same thickness and the same area in plan view, It is possible to improve the balance between the stress generated on the lower surface side of the diaphragm 5H and the stress generated on the upper surface side of the diaphragm 5H, and to prevent warping (bending) of the diaphragm 5H when no external pressure is applied to the pressure switch 1H at room temperature. can be suppressed more effectively.

Furthermore, by making the opposing metal film 8aH electrically independent, there is no need to form a lead wiring extending from the opposing metal film 8aH to the diaphragm 5H, so that the lid-side movable contact electrode 8H and the opposing metal film 8aH are arranged in a plane. As a result, by increasing the symmetry between the lid side movable contact electrode 8H and the opposing metal film 8aH, the stress generated on the lower surface side of the diaphragm 5H and the stress generated on the upper surface side of the diaphragm 5H can be reduced. It is possible to improve the balance with the stress generated in the diaphragm 5H, and it is possible to more effectively suppress warping (deflection) of the diaphragm 5H in a state where no external pressure is applied to the pressure switch 1H at room temperature.

In addition, it is possible to adjust the air pressure inside the airtight space by the outside air pressure when airtightly sealing. For example, if the outside air pressure at the time of airtight sealing is 1000 Pascal, the air pressure inside the airtight space will be 1000 Pascal, Using 1000 Pa as a threshold, if the external pressure is greater than 1000 Pa, the state shown in Figure 12(b) will occur and electricity will flow, and if the external pressure is less than 1000 Pa, the state shown in Figure 11(a) will occur and electricity will flow. will not flow. Therefore, it is possible to more appropriately test devices whose normal operation is guaranteed at an atmospheric pressure of 1000 Pascal or less.

≪Tenth embodiment≫
A pressure switch 1I according to a tenth embodiment of the present invention will be described with reference to FIG. 14. In the ninth embodiment, the fixed contact (base-side fixed contact electrode 11H) is composed of one multilayer electrode film, whereas in the tenth embodiment, the fixed contact is divided into two multilayer electrodes. It is composed of a membrane. Note that, in the tenth embodiment, parts having the same configuration as those in the ninth embodiment are given the same reference numerals as in the ninth embodiment, and a description thereof will be omitted.

The pressure switch 1I is configured to include a base substrate 2I and a lid substrate 3I arranged opposite to the base substrate 2I. For example, the same material as the base substrate 2H and lid substrate 3H of the ninth embodiment can be used as the material of the base substrate 2I and the lid substrate 3I.

The lid board 3I has a substantially rectangular shape in plan view when viewed from the upper side to the lower side in FIG. A recess 4AI having a substantially circular shape in a plan view is formed at approximately the center on the lower surface of the lid substrate 3I (the surface facing the base substrate 2I when the pressure switch 1I is assembled). ), a depression 4BI having a substantially circular shape in plan view is formed at substantially the center in plan view. The depression 4AI and the depression 4BI substantially overlap each other in plan view (at substantially the same position in plan view) and have substantially the same area in plan view. A thin diaphragm 5I is formed in a portion that constitutes the bottom surface of the depression 4AI and the bottom surface of the depression 4BI. As the thickness of the diaphragm 5I (thickness in the vertical direction of the drawing), for example, the same thickness as the diaphragm 5H of the ninth embodiment can be used.

In the lid substrate 3I, the peripheral portion of the thin diaphragm 5I formed on the lid substrate 3I in plan view is thicker than the diaphragm 5I, and the thickness of the diaphragm 5I is thicker than the diaphragm 5I. The meat part (base part) 6I is integrally molded.

The base substrate 2I has a substantially rectangular shape in a plan view viewed from the upper side to the lower side in FIG. By joining the lid substrate 3I and the base substrate 2I, a lid side movable contact electrode 8I forming a movable contact to be described later and a first electrode to form a fixed contact to be described later are placed in the recess 4BI portion forming the lower surface portion of the diaphragm 5I. , second fixed contact electrodes 11AI and 11BI are arranged, and an airtight space in which the diaphragm 5I can be deformed is formed.

On the lower surface of the diaphragm 5I formed on the lid substrate 3I (the surface facing the base substrate 2I when the pressure switch 1I is assembled), there is an electrode film having a substantially circular shape in plan view, located approximately at the center in plan view. A lid-side movable contact electrode 8I is provided. Under the vacuum of FIG. 14(a), the lid-side movable contact electrode 8I is separated from and does not come into contact with other electrodes such as first and second fixed contact electrodes 11AI and 11BI on the base substrate 2I side, which will be described later. 14(b), it comes into contact with each of a first fixed contact electrode 11AI and a second fixed contact electrode 11BI on the base substrate 2I side, which will be described later. The lid-side movable contact electrode 8I has the same film configuration as the lid-side movable contact electrode 8H of the ninth embodiment, and includes a first Ti film, a first Au film, and a second Au film in order from the diaphragm 5I side. Ti films are laminated. Further, the thickness of each metal film constituting the lid-side movable contact electrode 8I is the same as the thickness of each metal film constituting the lid-side movable contact electrode 8H of the ninth embodiment, for example. The thickness of the first Ti film is 300 Å, the thickness of the first Au film one layer above it is 2000 Å, and the thickness of the second Ti film one layer above it is 300 Å.

On the upper surface 5Ia of the diaphragm 5I of the lid substrate 3I, as shown in FIG. 14, a facing metal film 8aI that pairs with the lid-side movable contact electrode 8I is formed. The opposing metal film 8aI has the same structure and the same thickness as the lid-side movable contact electrode 8I (the thickness in the vertical direction in FIG. 14(a) is the same). They have the same film configuration, and the film thickness of each metal film is the same as the film thickness of the corresponding metal film of the lid side movable contact electrode 8I. In this embodiment, the opposing metal film 8aI includes a first Ti film stacked on the upper surface 5Ia of the diaphragm 5I, a first Au film stacked on the first Ti film, and a first Au film stacked on the first Ti film. It consists of a second Ti film laminated on an Au film, and for example, the thickness of the first Ti film is 300 Å, the thickness of the first Au film one layer above it is 200 Å, and the thickness of the first Ti film is 200 Å. The thickness of the second Ti film, which is the upper layer, is 300 Å. In addition, the opposing metal film 8aI substantially overlaps with the lid-side movable contact electrode 8I (at substantially the same position as the lid-side movable contact electrode 8I) in a plan view from the upper side to the lower side in FIG. 14(a). ), and is formed to have approximately the same area as the lid-side movable contact electrode 8I. Further, the opposing metal film 8aI is not in contact with other metal films and is electrically independent.

A first lid-side bonding electrode 9I and a second lid-side bonding electrode 10I, each of which is an electrode film, are provided on the surface of the thick portion 6I (base portion) of the lid substrate 3I facing the base substrate 2I. It is formed. The lid-side first bonding electrode 9I and the lid-side second bonding electrode 10I have the same film configuration as the lid-side first bonding electrode 9H and the lid-side second bonding electrode 10H of the ninth embodiment. A first Ti film, a first Au film, a second Ti film, and a second Au film are laminated in order from the side facing the base substrate 2I of the thick portion 6I (base portion) of the substrate 3I. . The thickness of each metal film constituting the lid-side first bonding electrode 9I and the lid-side second bonding electrode 10I is the same as that of the lid-side first bonding electrode 9H and the lid-side second bonding electrode 9H of the ninth embodiment. For example, the thickness of the first Ti film is 300 Å, the thickness of the first Au film one layer above it is 200 Å, and the thickness of the first Ti film is 200 Å. The thickness of the second Ti film, which is the upper layer, is 300 Å, and the thickness of the second Au film, which is one layer above it, is 1000 Å. The lid-side movable contact electrode 8I, the lid-side first bonding electrode 9I, and the lid-side second bonding electrode 10I are arranged at a predetermined distance from each other and do not contact each other.

As shown in FIG. 14(a), on the upper surface of the base substrate 2I (the surface facing the lid substrate 3I when the pressure switch 1I is assembled), there are divided fixed contact electrodes, each of which is an electrode film. A first fixed contact electrode 11AI and a second fixed contact electrode 11BI, a first bonding electrode 13I, and a second bonding electrode 12I are formed. The first fixed contact electrode 11AI and the second fixed contact electrode 11BI are both formed on the upper surface of the base substrate 2I in a region facing the diaphragm 5I formed on the lid substrate 3I. When the diaphragm 5I is not deformed, the first fixed contact electrode 11AI, the second fixed contact electrode 11BI, and the lid-side movable contact electrode 8I are opposed to each other with a predetermined distance apart, and due to the deformation of the diaphragm 5I, , the contact/separation between the first fixed contact electrode 11AI and the second fixed contact electrode 11BI and the lid side movable contact electrode 8I is switched.

For example, the first fixed contact electrode 11AI and the second fixed contact electrode 11BI are each formed in a semicircular shape, and are arranged at a predetermined interval. The first bonding electrode 13AI is formed integrally with the first fixed contact electrode 11AI, and is formed on the upper surface of the base substrate 2I in a region facing the thick portion 6I (base portion) of the lid substrate 3I. The second bonding electrode 12I is formed integrally with the second fixed contact electrode 11BI, and is formed on the upper surface of the base substrate 2I in a region facing the thick portion 6I (base portion) of the lid substrate 3I. Note that the first fixed contact electrode 11AI and the first bonding electrode 13I are not in contact with the second fixed contact electrode 11BI and the second bonding electrode 12I.

The first fixed contact electrode 11AI, the second fixed contact electrode 11BI, the first bonding electrode 13I, and the second bonding electrode 12I are the base side fixed contact electrode 11H and the base side first bonding electrode of the ninth embodiment. It has the same film structure as the base-side second bonding electrode 13H and the base-side second bonding electrode 12H, and in order from the upper surface side of the base substrate 2I, a first Ti film, a first Au film, a second Ti film, and a second Au film. are layered. The thickness of each metal film constituting the first fixed contact electrode 11AI, the second fixed contact electrode 11BI, the first bonding electrode 13I, and the second bonding electrode 12I is the same as that of the base side fixed contact of the ninth embodiment. The film thickness is the same as that of each metal film constituting the base-side first bonding electrode 11H, the base-side first bonding electrode 13H, and the base-side second bonding electrode 12H. For example, the thickness of the first Ti film is 300 Å, The thickness of the first Au film one layer above it is 2000 Å, the thickness of the second Ti film one layer above it is 300 Å, and the thickness of the second Au film one layer above it is 1000 Å.

Note that in this embodiment, as in the ninth embodiment, the first bonding electrode 9I and the second bonding electrode 10I on the lid substrate 3I side and the first bonding electrode on the base substrate 2A side are finally connected. An airtight space is formed by diffusion bonding the uppermost Au films of each of the electrodes 13I and 12I.

When the pressure switch 1I in FIG. 14(a) is placed in a vacuum, the external pressure of the pressure switch 1I and the pressure in the airtight space formed between the base substrate 2I and the lid substrate 3I are approximately the same. Alternatively, if the external pressure of the pressure switch 1I is negative with respect to the air pressure of the airtight space formed between the base board 2I and the lid board 3I, the diaphragm 5I expands outward, so the lid board 3I side The lid side movable contact electrode 8I and each of the first fixed contact electrode 11AI and the second fixed contact electrode 11BI on the base substrate 2I side are separated from each other and do not contact each other. This results in an open loop (broken wire) and no current flows.

When the degree of vacuum in the space in which the pressure switch 1I in FIG. The pressure becomes higher than the atmospheric pressure, and the diaphragm 5I bends (warps) toward the upper surface of the base substrate 2I, causing the lid-side movable contact electrode 8I on the diaphragm 5I side of the lid substrate 3I and the first fixed contact electrode 11AI on the base substrate 2I side. and the second fixed contact electrode 11BI are in contact with each other. This creates a closed loop (short circuit) and allows current to flow.

According to this embodiment, the same effects as the above-described ninth embodiment are achieved. Furthermore, compared to the ninth embodiment, the electrode film follows the diaphragm 5I more closely, and unexpected deformation of the diaphragm 5I due to film stress can be suppressed. Moreover, the movable contact electrode 8I plays a role of electrically connecting the first fixed contact electrode 11AI and the second fixed contact electrode 11BI when the diaphragm 5I is bent due to a pressure change, There is no need to form an extraction electrode for electrical connection with. This solves the problem of electrode breakage (disconnection) and unstable connection when forming extraction electrodes in areas with different thicknesses of the lid substrate 3I (at the boundary between the recess and the thick part 6I). .

<<Eleventh embodiment>>
A pressure switch 1J according to an eleventh embodiment of the present invention will be described with reference to FIG. 15. In the tenth embodiment, the first fixed contact electrode 11AI and the second fixed contact electrode 11BI are formed on the base substrate 2I, whereas in the eleventh embodiment, a diaphragm is also formed on the base substrate 2J side. 5J is formed, and a base-side first movable contact electrode 11AJ and a base-side second movable contact electrode 11BJ are arranged in place of the first fixed contact electrode 11AI and the second fixed contact electrode 11BI. There is. Further, in the eleventh embodiment, an opposing metal film 11aAJ that pairs with the base-side first movable contact electrode 11AJ and an opposing metal film 11aBJ that pairs with the base-side second movable contact electrode 11BJ are provided. There is. Note that in the eleventh embodiment, parts having the same configuration as those in the ninth embodiment or the tenth embodiment are given the same reference numerals as in the ninth embodiment or the tenth embodiment. The explanation will be omitted.

The base substrate 2J has a substantially rectangular shape in plan view when viewed from the upper side to the lower side in FIG. A depression 7J having a substantially circular shape in plan view is formed on the opposite surface) at substantially the center in plan view. The depression 7J and the depressions 4AI and 4BI on the lid substrate 3I side substantially overlap each other in plan view (located in substantially the same position in plan view), and have substantially the same area in plan view. A thin diaphragm 5J is formed in a portion constituting the bottom surface of the recess 7J.

The diaphragm 5J substantially overlaps the diaphragm 5I on the lid substrate 3I side (located at substantially the same position in the plan view) in a plan view from the top to the bottom in FIG. Diaphragms 5I and 5J are arranged facing each other. For example, the same thickness as the diaphragm 5H of the ninth embodiment can be used as the thickness of the diaphragm 5J (thickness in the vertical direction of the drawing).

In the base substrate 2J, the peripheral portion of the thin diaphragm 5J formed on the base substrate 2J in plan view is thicker than the diaphragm 5J, and the thickness of the diaphragm 5J is thicker than that of the diaphragm 5J. The meat part (base part) 6J is integrally molded.

On the upper surface of the diaphragm 5J formed on the base substrate 2J (the surface facing the lid substrate 3I when the pressure switch 1J is assembled), there are electrode films each having a semicircular shape and separated by a predetermined distance. , a base-side first movable contact electrode 11AJ and a base-side second movable contact electrode 11BJ are provided. Under vacuum in FIG. 15(a), the lid-side movable contact electrode 8I contacts other electrodes such as the base-side first movable contact electrode 11AJ and the base-side second movable contact electrode 11BJ formed on the base substrate 2J. Instead, it comes into contact with each of the base-side first movable contact electrode 11AJ and the base-side second movable contact electrode 11BJ under atmospheric pressure as shown in FIG. 15(b). The base-side first movable contact electrode 11AJ and the base-side second movable contact electrode 11BJ have the same membrane configuration as the first fixed contact electrode 11AI and the second fixed contact electrode 11BI of the tenth embodiment. , a first Ti film, a first Au film, a second Ti film, and a second Au film are laminated in order from the upper surface side of the diaphragm 5J. The thickness of each metal film constituting the base-side first movable contact electrode 11AJ and the base-side second movable contact electrode 11BJ is the same as that of the first fixed contact electrode 11AI and the second fixed contact electrode of the tenth embodiment. The thickness is the same as that of each metal film constituting 11BI, for example, the thickness of the first Ti film is 300 Å, the thickness of the first Au film one layer above it is 200 Å, and the thickness of the first Au film one layer above it is 300 Å. The thickness of the second Ti film is 300 Å, and the thickness of the second Au film one layer above it is 1000 Å.

The first bonding electrode 13J is integrally formed with the base-side first movable contact electrode 11AJ, and is an area (base portion) on the upper surface of the base substrate 2J that faces the thick portion 6I (base portion) of the lid substrate 3I. 6J). The second bonding electrode 12J is integrally formed with the base-side second movable contact electrode 11BJ, and is an area (base portion) on the upper surface of the base substrate 2J that faces the thick portion 6I (base portion) of the lid substrate 3I. 6J). Note that the first bonding electrode 13J and the base-side first movable contact electrode 11AJ are not in contact with the second bonding electrode 12J and the base-side second movable contact electrode 11BJ.

The first bonding electrode 13J and the second bonding electrode 12J both have the same film configuration as the first bonding electrode 13I and the second bonding electrode 12I of the tenth embodiment, and are located on the upper surface of the base substrate 2J. A first Ti film, a first Au film, a second Ti film, and a second Au film are laminated in order from the side. The film thickness of each metal film constituting the first bonding electrode 13J and the second bonding electrode 12J is the same as that of each metal film constituting the first bonding electrode 13I and the second bonding electrode 12I of the tenth embodiment. For example, the thickness of the first Ti film is 300 Å, the thickness of the first Au film one layer above it is 2000 Å, and the thickness of the second Ti film one layer above it is the same as the film thickness. The thickness is 300 Å, and the thickness of the second Au film one layer above it is 1000 Å.

As shown in FIG. 15, on the lower surface 5aJ of the diaphragm 5J (the surface opposite to the surface facing the diaphragm 5I), a first opposing metal film 11aAJ that pairs with the base-side first movable contact electrode 11AJ is formed. At the same time, a second opposing metal film 11aBJ that pairs with the base-side second movable contact electrode 11BJ is formed. The first opposing metal film 11aAJ has the same structure and the same thickness as the base-side first movable contact electrode 11AJ (the thickness in the vertical direction in FIG. 15(a) is the same). It has the same film configuration as the contact electrode 11AJ, and the thickness of each metal film is the same as the thickness of the corresponding metal film of the base-side first movable contact electrode 11AJ. Further, the second opposing metal film 11aBJ has the same structure and the same thickness as the base-side second movable contact electrode 11BJ (the thickness in the vertical direction in FIG. 15(a) is the same). It has the same film configuration as the second movable contact electrode 11BJ, and the thickness of each metal film is the same as the corresponding metal film thickness of the base-side second movable contact electrode 11BJ. In this embodiment, the first opposing metal film 11aAJ and the second opposing metal film 11aBJ include a first Ti film laminated on the lower surface 5aJ of the diaphragm 5J, and a first Ti film laminated on the first Ti film. It is composed of an Au film, a second Ti film laminated on the first Au film, and a second Au film laminated on the second Ti film. The thickness of the Ti film is 300 Å, the thickness of the first Au film one layer above it is 2000 Å, the thickness of the second Ti film one layer above it is 300 Å, and the thickness of the second Au film one layer above it is 300 Å. The thickness of the film is 1000 Å. Further, the first opposing metal film 11aAJ and the second opposing metal film 11aBJ are respectively. In a plan view seen from the upper side to the lower side in FIG. 11AJ and the base-side second movable contact electrode 11BJ), and in approximately the same area as the base-side first movable contact electrode 11AJ and the base-side second movable contact electrode 11BJ. Further, the first opposing metal film 11aAJ and the second opposing metal film 11aBJ are respectively. It is not in contact with other metal films and is electrically independent.

The lid substrate 3I, the various electrodes 8I, 9I, 10I formed on the lid substrate 3I, and the opposing metal film 8aI are the same as in the tenth embodiment, so the same reference numerals are given and the explanation will be omitted.

Note that in this embodiment, as in the first embodiment, the first bonding electrode 9I and the second bonding electrode 10I on the lid substrate 3I side and the first bonding electrode on the base substrate 2J side are finally connected. An airtight space is formed by diffusion bonding the uppermost Au films of each of the second bonding electrode 13J and the second bonding electrode 12J.

When the pressure switch 1J in FIG. 15(a) is placed in a vacuum, the external pressure of the pressure switch 1J and the pressure in the airtight space formed between the base substrate 2J and the lid substrate 3I are approximately the same. Alternatively, if the external pressure of the pressure switch 1J is a negative pressure with respect to the air pressure of the airtight space formed between the base board 2J and the lid board 3I, the diaphragm 5I on the lid board 3I side and the diaphragm on the base board 2J side Since 5J expands outward, it is connected to each of the lid-side movable contact electrode 8I on the lid board 3I side, the base-side first movable contact electrode 11AJ and the base-side second movable contact electrode 11BJ on the base board 2J side. are separated and do not touch. This results in an open loop (broken wire) and no current flows.

When the degree of vacuum in the space in which the pressure switch 1J in FIG. The pressure becomes higher than the atmospheric pressure, and the diaphragm 5I on the lid board 3I side bends (warps) toward the diaphragm 5J on the base board 2J side, and the diaphragm 5J on the base board 2J side also bends (warps) toward the diaphragm 5I side on the lid board 3I. . As a result, the lid-side movable contact electrode 8I on the diaphragm 5I side of the lid substrate 3I comes into contact with each of the base-side first movable contact electrode 11AJ and the base-side second movable contact electrode 11BJ on the base substrate 2J side. . This creates a closed loop (short circuit) and allows current to flow.

According to this embodiment, the same effects as the above-described ninth embodiment are achieved. In addition, the two diaphragms 5I, 5J can be deformed, and the two diaphragms 5I, 5J can come into contact with each other with a smaller amount of displacement, so pressure can be detected more sensitively.

≪Twelfth embodiment≫
A pressure switch 1K according to a twelfth embodiment of the present invention will be described with reference to FIG. 16. In the tenth embodiment, divided fixed contacts (first and second fixed contact electrodes 11AI, 11BI) are arranged on the upper surface of the base substrate 2I, whereas in the twelfth embodiment, the lid A cover substrate 30K is bonded to the upper surface of the substrate 3K, and divided fixed contact electrodes (first fixed contact electrode 11EK, second fixed contact electrode 11FK) are arranged on the lower surface of the cover substrate 30K. In addition, when the outside is in a vacuum state, the first and second fixed contact electrodes 11EK and 11FK and the movable contact electrode 8K arranged on the diaphragm 5K come into contact, forming a closed loop (short circuit) and causing current to flow. It has become. Note that in the twelfth embodiment, parts having the same configuration as those in the ninth to eleventh embodiments are given the same reference numerals as in the ninth to eleventh embodiments. The explanation will be omitted.

The pressure switch 1K is configured to include a base substrate 2K, a lid substrate 3K placed opposite to the base substrate 2K, and a cover substrate 30K placed opposite to the lid substrate 3K. For example, the same material as the base substrate 2H and lid substrate 3H of the ninth embodiment can be used as the material of the base substrate 2K and the lid substrate 3K. Similarly, the cover substrate 30K can be made of the same material (eg, crystal, glass) as the base substrate 2H of the ninth embodiment.

The lid board 3K has a substantially rectangular shape in plan view when viewed from the top to the bottom in FIG. ), a recess 4K (concave portion) having a substantially circular shape in plan view is formed at approximately the center in plan view, and a thin diaphragm 5K is formed at the bottom of the recess 4K.

In the lid substrate 3K, the peripheral portion of the thin diaphragm 5K formed on the lower surface of the lid substrate 3K in plan view is thicker than the diaphragm 5K, and is thicker than the diaphragm 5K and the diaphragm 5K. The thick wall portion 6K (hereinafter referred to as the "base portion" as appropriate) is integrally molded from the same material.

On the upper surface of the diaphragm 5K formed on the lid substrate 3K (the surface facing the cover substrate 30K when the pressure switch 1K is assembled), there is an electrode for a movable contact that is approximately circular in plan view and located approximately in the center. 8K is provided. The movable contact electrode 8K contacts other electrodes such as the first and second fixed contact electrodes 11EK and 11FK on the cover substrate 30K side, which will be described later, under the vacuum shown in FIG. Under atmospheric pressure, it does not come into contact with each of the first fixed contact electrode 11EK and the second fixed contact electrode 11FK on the cover substrate 30K side, which will be described later. The movable contact electrode 8K has the same film configuration as the lid side movable contact electrode 8H of the ninth embodiment, and includes a first Ti film, a first Au film, and a second Ti film in order from the diaphragm 5K side. The membranes are laminated. The thickness of each metal film constituting the movable contact electrode 8K is the same as the thickness of each metal film constituting the lid-side movable contact electrode 8H of the ninth embodiment. The thickness of the Ti film is 300 Å, the thickness of the first Au film one layer above it is 2000 Å, and the thickness of the second Ti film one layer above it is 300 Å.

In addition, as shown in FIG. 16(a), on the upper surface of the lid substrate 3K, a portion excluding the region where the diaphragm 5K is formed (a portion corresponding to the thick portion 6K) is provided with a lid-side first bonding electrode 9K. A lid-side second bonding electrode 10K is formed. The lid-side first bonding electrode 9K does not contact either the movable contact electrode 8K or the lid-side second bonding electrode 10K. Moreover, the lid-side second bonding electrode 10K does not contact either the movable contact electrode 8K or the lid-side first bonding electrode 9K. The first bonding electrode 9K on the lid side and the second bonding electrode 10K on the lid side include a first Ti film, a first Au film, a second Ti film, and a second Au film in order from the top surface of the lid substrate 3K. For example, the thickness of the first Ti film is 300 Å, the thickness of the first Au film one layer above it is 2000 Å, the thickness of the second Ti film one layer above it is 300 Å, The thickness of the second Au film, which is one layer above it, is 1000 Å.

On the lower surface of the lid substrate 3K (the surface facing the base substrate 2K when the pressure switch 1K is assembled), there is a lid-side third A bonding electrode 18K is formed. The lid-side third bonding electrode 18K includes a first Ti film, a first Au film, a second Ti film, and a second Au film stacked in order from the bottom surface of the lid substrate 3K.

On the lower surface 5aK of the diaphragm 5K of the lid substrate 3K, as shown in FIG. 16, a counter metal film 8aK that pairs with the movable contact electrode 8K is formed. The opposing metal film 8aK has the same structure and the same thickness as the movable contact electrode 8K (the thickness in the vertical direction in FIG. 16(a) is the same). In addition, the thickness of each metal film is the same as the thickness of the corresponding metal film of the movable contact electrode 8K. In this embodiment, the opposing metal film 8aK includes a first Ti film stacked on the lower surface 5aK of the diaphragm 5K, a first Au film stacked on the first Ti film, and a first Au film stacked on the first Ti film. It consists of a second Ti film laminated on an Au film, and for example, the thickness of the first Ti film is 300 Å, the thickness of the first Au film one layer above it is 200 Å, and the thickness of the first Ti film is 200 Å. The thickness of the second Ti film, which is the upper layer, is 300 Å. In addition, the opposing metal film 8aK substantially overlaps the movable contact electrode 8K (at substantially the same position as the movable contact electrode 8K) in a plan view when looking from the upper side to the lower side in FIG. It is formed with approximately the same area as the electrode 8K. Further, the opposing metal film 8aK is not in contact with other metal films and is electrically independent.

As shown in FIG. 16(a), a through hole 21K is formed in the cover substrate 30K in a region overlapping the approximate center of the diaphragm 5K formed in the lid substrate 3K when the pressure switch 1K is assembled. It is formed. Thereby, the pressure switch 1K is configured so that the external atmospheric pressure is applied to the diaphragm 5K.

On the lower surface of the cover substrate 30K (the surface facing the lid substrate 3K when the pressure switch 1K is assembled), there are divided fixed contact electrodes, a first fixed contact electrode 11EK and a second fixed contact electrode 11FK. , a cover-side first bonding electrode 13K, and a cover-side second bonding electrode 12K are formed. The first fixed contact electrode 11EK and the second fixed contact electrode 11FK are both located in a region on the lower surface of the cover substrate 30K that faces the diaphragm 5K formed on the lid substrate 3K, and are opposed to each other with the through hole 21K as a boundary. will be placed. For example, the first fixed contact electrode 11EK and the second fixed contact electrode 11FK are each formed in a semicircular shape.

The cover side first bonding electrode 13K is formed integrally with the first fixed contact electrode 11EK, and is formed in a region facing the thick portion 6K of the lid substrate 3K on the lower surface of the cover substrate 30K. The cover-side second bonding electrode 12K is formed integrally with the second fixed contact electrode 11FK, and is formed on the lower surface of the cover substrate 30K in a region facing the thick portion 6K of the lid substrate 3K. Note that the first fixed contact electrode 11EK and the cover side first bonding electrode 13K are not in contact with and are not electrically connected to the second fixed contact electrode 11FK and the cover side second bonding electrode 12K. . In addition, each of the first fixed contact electrode 11EK and the second fixed contact electrode 11FK is in contact with the movable contact electrode 8K arranged on the diaphragm 5K in a state where the diaphragm 5K is not deformed.

The first fixed contact electrode 11EK, the second fixed contact electrode 11FK, the cover side first bonding electrode 13K, and the cover side second bonding electrode 12K are all made of a first Ti film in order from the bottom surface of the cover substrate 30K. , a first Au film, a second Ti film, and a second Au film are stacked. Also, for example, the thickness of the first Ti film is 300 Å, the thickness of the first Au film one layer above it is 2000 Å, the thickness of the second Ti film one layer above it is 300 Å, and one of the The thickness of the upper second Au film is 1000 Å.

On the upper surface of the cover substrate 30K, a first external connection electrode 14Kc for external connection having a vertically long rectangular shape is formed at the right end, and a second external connection electrode 14Kd for external connection having a vertically long rectangular shape at the left end. Ru.

The cover substrate 30K includes a first interlayer connection conductor 15Kc that connects the first external connection electrode 14Kc formed on the top surface and the cover side first bonding electrode 13K formed on the bottom surface, and a first interlayer connection conductor 15Kc formed on the top surface. A second interlayer connection conductor 15Kd is formed to connect the second external connection electrode 14Kd and the cover-side second bonding electrode 12K formed on the lower surface.

The base substrate 2K has a substantially rectangular shape in a plan view viewed from the upper side to the lower side in FIG. By joining the lid substrate 3K and the base substrate 2K, an airtight space is formed that allows the diaphragm 5K formed on the lid substrate 3K to be deformed.

On the upper surface of the base substrate 2K (the surface facing the lid substrate 3K when the pressure switch 1K is assembled), a base-side bonding electrode 17K is formed at a location that comes into contact with the thick portion 6K of the lid substrate 3K. . The base-side bonding electrode 17K includes a first Ti film, a first Au film, a second Ti film, and a second Au film stacked in this order from the top surface of the base substrate 2K.

Note that in this embodiment, as in the ninth embodiment, the Au films of the uppermost layers of the third bonding electrode 18K on the lid side and the bonding electrode 17K on the base side are finally diffusion bonded to each other. As a result, an airtight space is formed. In addition, the Au films of the top layer of each of the first bonding electrode 9K on the lid side, the second bonding electrode 10K on the lid side, the first bonding electrode 13K on the cover side, and the second bonding electrode 12K on the cover side are diffusion bonded to each other. By doing so, the cover substrate 30K and the lid substrate 3K are joined.

When the pressure switch 1K in FIG. 16(a) is placed in a vacuum, the external pressure of the pressure switch 1K and the pressure in the airtight space formed between the base substrate 2K and the lid substrate 3K are approximately the same. Alternatively, if the external pressure of the pressure switch 1K is negative with respect to the air pressure of the airtight space formed between the base board 2K and the lid board 3K, the diaphragm 5K on the lid board 3K side expands outward. , the movable contact electrode 8K on the lid substrate 3K side contacts each of the first fixed contact electrode 11EK and the second fixed contact electrode 11FK on the cover substrate 30K side. This creates a closed loop (short circuit) and allows current to flow.

When the degree of vacuum in the space in which the pressure switch 1K in FIG. The pressure becomes higher than the atmospheric pressure, and the diaphragm 5K on the lid substrate 3K side bends (warps) toward the base substrate 2K side. As a result, the movable contact electrode 8K on the diaphragm 5K side and the first fixed contact electrode 11EK and the second fixed contact electrode 11FK on the cover substrate 30K side are separated, resulting in an open loop (broken wire) and a current flow. will not flow.

According to this embodiment, the same effects as the above-described ninth embodiment are achieved. Moreover, contrary to the ninth to eleventh embodiments, it is possible to provide a pressure switch 1K that becomes a closed loop when placed under vacuum.

≪Thirteenth embodiment≫
A pressure switch 1L according to a sixth embodiment of the present invention will be described with reference to FIG. 17. The pressure switch 1L of the thirteenth embodiment is different from the pressure switch 1H of the ninth embodiment in that an upper substrate 40L is disposed on the upper surface 30Ha of the lid substrate 3H. Note that, in the thirteenth embodiment, parts having the same configuration as those in the ninth embodiment are given the same reference numerals as those in the ninth embodiment, and a description thereof will be omitted.

The pressure switch 1L includes a base substrate 2H, a lid substrate 3H whose lower surface 30Hb is arranged opposite to the upper surface 20Ha of the base substrate 2H, and a lid substrate 3H whose lower surface 40Lb is arranged opposite to the upper surface 30Ha of the lid substrate 3H. It is configured to include a plate substrate 40L.

The upper substrate 40L has a substantially rectangular shape when viewed from above in a direction from the top to the bottom in FIG. The upper substrate 40L is provided with a penetrating portion 40Lc in a region that overlaps with the recess 4H of the lid substrate 3H in a plan view of the upper substrate 40L. By providing the penetration portion 40Lc in the area of the upper substrate 40L, the air pressure in the space formed between the upper substrate 40L and the lid substrate 3H (the portion of the recess 4H of the lid substrate 3H) can be adjusted to the outside of the pressure switch 1L. It will be the same as the atmospheric pressure.

On the upper surface of the thick portion 6H of the lid substrate 3H (the surface facing the upper substrate 40L when the pressure switch 1L is assembled), there is a lid-side joint on almost the entire area that contacts the upper substrate 40L. An electrode 41L is formed. In this embodiment, the lid side bonding electrode 41L includes a first Ti film laminated on the upper surface of the thick portion 6H, a first Au film laminated on the first Ti film, and a first Ti film laminated on the upper surface of the thick portion 6H. It is composed of a second Ti film laminated on the first Au film, and a second Au film laminated on the second Ti film. For example, the thickness of the first Ti film laminated on the upper surface 30Ha of the lid substrate 3H is 300 Å, the thickness of the first Au film one layer above it is 2000 Å, and the thickness of the second Ti film one layer above it is 300 Å. The film thickness is 300 Å, and the thickness of the second Au film one layer above it is 1000 Å. Note that in this embodiment, each metal film is formed by sputtering at a high temperature (for example, 150 to 200 degrees), but other film forming methods such as vapor deposition can be used. Note that the metal forming the film corresponding to each Ti film is not limited to Ti, and may be, for example, Cr, Ni, W, Mo, or an alloy thereof.

On the lower surface 40Lb of the upper substrate 40L (the surface facing the lid substrate 3H when the pressure switch 1L is assembled), there is a bonding plate for upper plate side bonding over almost the entire area that contacts the thick part 6H of the lid substrate 3H. An electrode 42L is formed. In this embodiment, the upper plate side bonding electrode 42L includes a first Ti film laminated on the lower surface 40Lb of the upper substrate 40L, and a first Au film laminated on the first Ti film. , a second Ti film laminated on the first Au film, and a second Au film laminated on the second Ti film. For example, the thickness of the first Ti film laminated on the lower surface 40Lb of the upper substrate 40L is 300 Å, the thickness of the first Au film one layer above it is 2000 Å, and the thickness of the second Ti film one layer above it is 300 Å. The thickness of the second Au film is 300 Å, and the thickness of the second Au film one layer above it is 1000 Å. Note that in this embodiment, each metal film is formed by sputtering at a high temperature (for example, 150 to 200 degrees), but other film forming methods such as vapor deposition can be used. Note that the metal forming the film corresponding to each Ti film is not limited to Ti, and may be, for example, Cr, Ni, W, Mo, or an alloy thereof.

By diffusion bonding (Au-Au bonding) the uppermost Au film that constitutes the lid side bonding electrode 41L and the uppermost Au film that constitutes the upper plate side bonding electrode 42L, the upper substrate 40L and The lid substrate 3H is joined. When bonding the lid substrate 3H and the upper substrate 40L using adhesive, there is a risk that the upper substrate 40L may be tilted with respect to the lid substrate 3H, but in diffusion bonding, the upper substrate 40L may be tilted with respect to the lid substrate 3H. The tilt of 40L can be suppressed. It goes without saying that if the upper substrate 40L is allowed to tilt with respect to the lid substrate 3H, the lid substrate 3H and the upper substrate 40L may be joined using an adhesive.

It is preferable to use, for example, the same material as the lid substrate 3H (eg, crystal, glass) as the material of the upper substrate 40L. By making the upper substrate 40L and the lid substrate 3H of the same material, it is possible to eliminate the difference in thermal conductivity between the two, and to reduce the stress applied to the joint between the upper substrate 40L and the lid substrate 3H. can.

When the pressure switch 1L in FIG. 17(a) is placed in a vacuum, the external pressure of the pressure switch 1L and the space formed between the upper substrate 40L and the lid substrate 3H (the depression 4H of the lid substrate 3H) The atmospheric pressure of the part) is the same. The air pressure in the recess 4H of the lid substrate 3H is the same as the air pressure in the airtight space formed between the base substrate 2H and the lid substrate 3H, or the air pressure in the recess 4H of the lid substrate 3H is the same as that of the base substrate 2H. If the pressure is negative with respect to the air pressure in the airtight space formed between the lid board 3H and the diaphragm 5H, the diaphragm 5H expands outward (towards the recess 4H), so the lid-side movable contact on the diaphragm 5H side of the lid board 3H The base-side fixed contact electrode 8H and the base-side fixed contact electrode 11H on the side of the depression 7H (recessed portion) of the base substrate 2H are separated from each other and do not come into contact with each other. This results in an open loop (broken wire) and no current flows.

When the degree of vacuum in the space in which the pressure switch 1L in FIG. The pressure becomes higher than the air pressure in the airtight space formed between 2H and the lid board 3H, and the diaphragm 5H bends (warps) toward the recess 7H of the base board 2H, causing the lid side movable contact on the diaphragm 5H side of the lid board 3H to The electrode 8H and the base-side fixed contact electrode 11H on the side of the recess 7H of the base substrate 2H are in contact with each other. This creates a closed loop (short circuit) and allows current to flow.

According to this embodiment, the same effects as the above-described ninth embodiment are achieved. Furthermore, the upper substrate 40L can protect the diaphragm 5H that constitutes the lid substrate 3H, thereby preventing, for example, a situation in which the diaphragm 5H is damaged and the function of the pressure switch 1L as a switch is deteriorated. can.

Note that the arrangement of the upper substrate on the upper surface side of the lid substrate is applicable to, for example, the tenth embodiment, the eleventh embodiment, the fifteenth embodiment, the sixteenth embodiment, and the like.

≪Fourteenth embodiment≫
A pressure switch 1M according to a fourteenth embodiment of the present invention will be described with reference to FIG. 18. In the pressure switches 1H and 1L of the ninth and thirteenth embodiments, first and second external connection electrodes 14Ha and 14Hb for external connection are formed on the lower surface 20Hb of the base substrate 2H. On the other hand, in the pressure switch 1M of the fourteenth embodiment, first and second external connection electrodes 46Ma and 46Mb for external connection are formed on the upper surface 40Ma of the upper substrate 40M. In addition, in the 14th embodiment, parts having the same configuration as the 9th or 13th embodiment are given the same reference numerals as in the 9th or 13th embodiment, and the description thereof will be omitted.

The pressure switch 1M includes a base substrate 2M, a lid substrate 3M whose lower surface 30Mb is arranged to face the upper surface 20Ma of the base substrate 2M, and an upper board whose lower surface 40Mb is arranged to face the upper surface 30Ma of the lid substrate 3M. 40M. The same material as the base substrate 2H and lid substrate 3H of the ninth and thirteenth embodiments can be used as the material of the base substrate 2M and the lid substrate 3M, and the upper substrate of the thirteenth embodiment can be used as the upper substrate 40M. The same material as 40L can be used.

The lid board 3M has a substantially rectangular shape in plan view when viewed from the top to the bottom in FIG. A depression 4H (concavity) having a substantially circular shape in plan view is formed on the surface (opposite to the surface opposite to the surface opposite to the surface opposite to the surface) at substantially the center in plan view. As a result, the lid substrate 3M includes a thin diaphragm 5H and a thick portion (base portion) 6M that is thicker than the thin diaphragm 5H around the thin diaphragm 5H in a plan view. In the lid substrate 3M, the diaphragm 5H and the thick portion 6M are integrally molded from the same material.

On the lower surface 30Mb of the lid substrate 3M, an electrode 8H for a lid-side movable contact, which forms a movable contact of the pressure switch 1M, and an electrode 8H for a lid-side movable contact, which has the same shape and the same membrane structure as the ninth embodiment, are provided. The lid-side first bonding electrode 9H integrally formed, and the lid-side second bonding electrode 10H that is not in contact with either the lid-side movable contact electrode 8H or the lid-side first bonding electrode 9H. It is formed.

On the upper surface 5Ha of the diaphragm 5H of the lid substrate 3M, there is formed a counter metal film 8aH that pairs with the lid-side movable contact electrode 8H, which has the same shape and the same film structure as the ninth embodiment. The opposing metal film 8aH substantially overlaps the lid-side movable contact electrode 8H (at substantially the same position as the lid-side movable contact electrode 8H) in a plan view from the upper side to the lower side in FIG. 18(a), It is formed to have approximately the same area as the lid-side movable contact electrode 8H. Further, the opposing metal film 8aH is not in contact with other metal films and is electrically independent.

On the upper surface of the thick part 6M constituting the lid substrate 3M (the surface facing the upper substrate 40M when the pressure switch 1M is assembled), there is a lid-side first bonding plate at the place where it comes into contact with the upper substrate 40M. An electrode 42Ma and a lid-side second bonding electrode 42Mb not in contact with the lid-side first bonding electrode 42Ma are formed. In this embodiment, the lid-side first bonding electrode 42Ma and the lid-side second bonding electrode 42Mb are connected to the first Ti film laminated on the upper surface of the thick portion 6M, and the first Ti film, respectively. It is composed of a first Au film stacked on top, a second Ti film stacked on the first Au film, and a second Au film stacked on the second Ti film. ing. For example, the thickness of the first Ti film laminated on the upper surface of the thick portion 6M is 300 Å, the thickness of the first Au film one layer above it is 2000 Å, and the thickness of the second Ti film one layer above it is 300 Å. The film thickness is 300 Å, and the thickness of the second Au film one layer above it is 1000 Å. Note that in this embodiment, each metal film is formed by sputtering at a high temperature (for example, 150 to 200 degrees), but other film forming methods such as vapor deposition can be used. Note that the metal forming the film corresponding to each Ti film is not limited to Ti, and may be, for example, Cr, Ni, W, Mo, or an alloy thereof.

The lid substrate 3M includes a lid-side first bonding electrode 42Ma formed on the upper surface of the thick portion 6M constituting the lid substrate 3M, and a lid-side first bonding electrode 9H formed on the bottom surface 30Mb of the lid substrate 3M. A first interlayer connection conductor 45Ma is formed to connect the two. The lid substrate 3M also includes a lid-side second bonding electrode 42Mb formed on the upper surface of the thick portion 6M constituting the lid substrate 3M, and a lid-side second bonding electrode 42Mb formed on the bottom surface 30Mb of the lid substrate 3M. A second interlayer connection conductor 45Mb is formed to connect to the electrode 10H. The first and second interlayer connection conductors 45Ma and 45Mb are each formed of, for example, a through hole whose inner wall surface is coated with a metal film. Note that the first and second interlayer connection conductors 45Ma and 45Mb may be formed using vias whose through holes are separately filled with a conductive material such as metal paste.

The base substrate 2M has a substantially rectangular shape in plan view when viewed from the upper side to the lower side in FIG. A depression 7H (concave portion) having a substantially circular shape in plan view is formed in the substantially center portion of the surface.

On the upper surface 20Ma of the base substrate 2M, there is a base-side fixed contact electrode 11H that forms a fixed contact of the pressure switch 1M, which has the same shape and the same membrane structure as the ninth embodiment, and the base-side fixed contact electrode 11H. The integrally formed base-side second bonding electrode 12H and the base-side first bonding electrode 13H, which is not in contact with either the base-side fixed contact electrode 11H or the base-side second bonding electrode 12H, are integrated. It is formed.

The lower surface 20Mb of the base substrate 2M has first and second external connection electrodes 14Ha and 14Hb for external connection formed on the lower surface 20Hb of the base substrate 2H of the ninth embodiment and the thirteenth embodiment. Corresponding first and second external connection electrodes for external connection are not formed. The base substrate 2M also has first and second interlayer connection conductors corresponding to the first and second interlayer connection conductors 15Ha and 15Hb formed on the base substrate 2H of the ninth embodiment and the thirteenth embodiment. No connecting conductor is formed.

The upper substrate 40M has a substantially rectangular shape in plan view when viewed from the upper side to the lower side in FIG. 40Lc is provided.

On the lower surface 40Mb of the upper substrate 40M (the surface facing the lid substrate 3M when the pressure switch 1M is assembled), there is a first upper-plate-side joint at a location that abuts the upper surface of the thick portion 6M of the lid substrate 3M. and an upper plate side second bonding electrode 41Mb that does not contact the upper plate side first bonding electrode 41Ma. In this embodiment, the upper plate side first bonding electrode 41Ma and the upper plate side second bonding electrode 41Mb are connected to the first Ti film laminated on the lower surface 40Mb of the upper substrate 40M, and the first a first Au film laminated on the Ti film, a second Ti film laminated on the first Au film, and a second Au film laminated on the second Ti film. It consists of For example, the thickness of the first Ti film laminated on the lower surface 40Mb of the upper substrate 40M is 300 Å, the thickness of the first Au film one layer above it is 2000 Å, and the thickness of the second Ti film one layer above it is 300 Å. The thickness of the second Au film is 300 Å, and the thickness of the second Au film one layer above it is 1000 Å. Note that in this embodiment, each metal film is formed by sputtering at a high temperature (for example, 150 to 200 degrees), but other film forming methods such as vapor deposition can be used. Note that the metal forming the film corresponding to each Ti film is not limited to Ti, and may be, for example, Cr, Ni, W, Mo, or an alloy thereof.

When the pressure switch 1M is assembled, in plan view, the upper plate side first bonding electrode 41Ma and the lid side first bonding electrode 42Ma are in an overlapping position, and the upper plate side second bonding electrode 41Mb and the lid side It is located in an overlapping position with the side second bonding electrode 42Mb. The uppermost Au film constituting the lid side first bonding electrode 42Ma and the uppermost Au film constituting the upper plate side first bonding electrode 41Ma are diffusion bonded (Au-Au bonding), and the lid side By diffusion bonding (Au-Au bonding) the uppermost Au film constituting the second bonding electrode 42Mb and the uppermost Au film constituting the upper plate side second bonding electrode 41Mb, the upper substrate 40M and the lid substrate 3M are joined.

On the upper surface 40Ma of the upper substrate 40M, there is a first external connection electrode 46Ma for external connection, which has a vertically long rectangular shape in plan view at the right end in plan view, and a vertically long rectangular shape in plan view at the left end in plan view. A second external connection electrode 46Mb that does not contact the first external connection electrode 46Ma is formed. The first external connection electrode 46Ma and the second external connection electrode 46Mb are, for example, Ti film/Au film/Ti film/ A multilayer structure of Au films may also be used. Thereby, the first external connection electrode 46Ma and the second external connection electrode 46Mb can be formed simultaneously with the upper plate side first bonding electrode 41Ma and the upper plate side second bonding electrode 41Mb.

A first interlayer connection conductor 47Ma is formed on the upper substrate 40M to connect the first external connection electrode 46Ma formed on the upper surface 40Ma and the upper plate side first bonding electrode 41Ma formed on the lower surface 40Mb. There is. Further, a second interlayer connection conductor 47Mb is formed on the upper substrate 40M to connect the second external connection electrode 46Mb formed on the upper surface 40Ma and the upper plate side second bonding electrode 41Mb formed on the lower surface 40Mb. has been done. The first and second interlayer connection conductors 47Ma and 47Mb are each formed of, for example, a through hole whose inner wall surface is coated with a metal film. Note that the first and second interlayer connection conductors 47Ma and 47Mb may be formed using vias whose through holes are separately filled with a conductive material such as metal paste.

The pressure switch 1M is fixed to the substrate SM using, for example, an adhesive GM such as a non-conductive adhesive, and the first external connection electrode 46Ma is connected to the first electrode 48Ma formed on the substrate SM by a wire WMa. , a second external connection electrode 46Mb is connected to a second electrode 48Mb formed on the substrate SM by a wire WMb.

When the pressure switch 1M in FIG. 18(a) is placed in a vacuum, the external pressure of the pressure switch 1M and the space formed between the upper substrate 40M and the lid substrate 3M (in the depression 4H of the lid substrate 3M) The atmospheric pressure of the part) is the same. The air pressure in the recess 4H of the lid substrate 3M is the same as the air pressure in the airtight space formed between the base substrate 2M and the lid substrate 3M, or the air pressure in the recess 4H of the lid substrate 3M is the same as that of the base substrate 2M. If the pressure is negative with respect to the air pressure in the airtight space formed between the lid board 3M and the diaphragm 5H, the diaphragm 5H expands outward (toward the recess 4H), so the lid side movable contact on the diaphragm 5H side of the lid board 3M The base-side fixed contact electrode 8H and the base-side fixed contact electrode 11H on the side of the recess 7H (concave portion) of the base substrate 2M are separated from each other and do not come into contact with each other. This results in an open loop (broken wire) and no current flows.

When the degree of vacuum in the space in which the pressure switch 1M in FIG. The pressure becomes higher than the air pressure in the airtight space formed between 2M and the lid board 3M, and the diaphragm 5H bends (warps) toward the recess 7H of the base board 2M, causing the lid side movable contact on the diaphragm 5H side of the lid board 3M to The electrode 8H and the base-side fixed contact electrode 11H on the side of the recess 7H of the base substrate 2M are in contact with each other. This creates a closed loop (short circuit) and allows current to flow.

According to this embodiment, the same effects as the above-described ninth embodiment and the same effects as the above-described thirteenth embodiment are achieved. Further, by mounting the pressure switch 1M on the substrate SM by wire bonding, there is no need to use flux (soldering accelerator), and the fear of contaminating the surrounding area can be suppressed. Moreover, since the possibility that adhesive or the like will interfere with the diaphragm 5H is reduced, malfunction of the pressure switch 1M can be avoided. In addition, by mounting the pressure switch 1M by wire bonding, even if the pressure switch 1M is a minute component, the first and second external connection electrodes 46Ma and 46Mb are reliably connected to the first and second electrodes 48Ma and 48Mb, respectively. can do. In addition, in the case of flip-chip mounting, there is a risk that large package distortion will occur because the pressure switch is fixed to the board at two or more different points. Wire bonding mounting is preferable to mounting.

Note that instead of arranging the first and second external connection electrodes for external connection on the lower surface of the base substrate, the first and second external connection electrodes for external connection are arranged on the upper surface of the upper substrate. , the 10th embodiment, the 11th embodiment, the 15th embodiment, the 16th embodiment, etc., after providing an upper substrate.

<<Fifteenth embodiment>>
A pressure switch 1N according to a fifteenth embodiment of the present invention will be described with reference to FIG. 19. The fifteenth embodiment relates to details of the shapes of the base substrate 2N and lid substrate 3N of the pressure switch 1N. Note that, in the fifteenth embodiment, parts having the same configuration as those in the ninth embodiment are given the same reference numerals as those in the ninth embodiment, and a description thereof will be omitted.

The pressure switch 1N is configured to include a base substrate 2N and a lid substrate 3N whose lower surface 30Nb is arranged to face the upper surface 20Na of the base substrate 2N. The same material as the base substrate 2H and lid substrate 3H of the ninth embodiment can be used as the material of the base substrate 2N and the lid substrate 3N, and in this embodiment, the base substrate 2N and the lid substrate 3N are AT Composed of cut crystals. The coordinate axes in FIG. 19 represent the crystal axes of AT-cut crystal, the X-axis is the electrical axis, the Y-axis is the mechanical axis, and the Z'-axis is the optical axis.

The lid board 3N has a substantially rectangular shape in plan view when viewed from the top to the bottom in FIG. A depression 4N (concave portion) having a substantially circular shape in plan view is formed on the surface opposite to the surface opposite to the surface in plan view. Thereby, the lid substrate 3N includes a thin diaphragm 5N and a thick portion (base portion) 6N that is thicker than the thin diaphragm 5N in a surrounding area of the thin diaphragm 5N in plan view. configured. In the lid substrate 3N, the diaphragm 5N and the thick portion 6N are integrally molded from the same material.

The depression 4N (concave portion) can be formed, for example, by wet etching the formation region of the depression 4N on the upper surface 30Na of the lid substrate 3N using photolithography technology.

In the thick portion 6N related to the depression 4N formed by wet etching the formation region of the depression 4N on the upper surface 30Na of the lid substrate 3N using photolithography technology, in the cross-sectional portion shown in the cross-sectional view in FIG. The outer side surface of the thick portion 6N is inclined so as to be located on the negative direction side of the Z' axis (to the right in FIG. 19) as it moves away from the upper surface of the thick portion 6N (angle of inclination≠90°). Further, in the cross-sectional area shown in FIG. 19, the inner side surface of the thick wall portion 6N is located on the negative direction side of the Z' axis (to the right side in FIG. 19) as it moves away from the top surface of the thick wall portion 6N. (angle of inclination ≠ 90°).

On the lower surface 30Nb of the lid substrate 3N, a lid-side movable contact electrode 8N forming a movable contact of the pressure switch 1N, and a lid-side first bonding electrode 9N integrally formed with the lid-side movable contact electrode 8N. , a lid-side second bonding electrode 10N that is not in contact with either the lid-side movable contact electrode 8N or the lid-side first bonding electrode 9N is formed. For example, the lid side movable contact electrode 8N, the lid side first bonding electrode 9N, and the lid side second bonding electrode 10N are respectively the lid side movable contact electrode 8H and the lid side movable contact electrode 8H of the ninth embodiment. It has the same shape and the same film structure as the first bonding electrode 9H and the lid-side second bonding electrode 10H.

A counter metal film 8aN that pairs with the movable contact electrode 8N is formed on the upper surface 5Na of the diaphragm 5N of the lid substrate 3N. The opposing metal film 8aN has the same structure and the same thickness as the movable contact electrode 8N (the thickness in the vertical direction in FIG. 19(a) is the same). In addition, the thickness of each metal film is the same as the thickness of the corresponding metal film of the movable contact electrode 8N. In addition, the opposing metal film 8aN substantially overlaps the movable contact electrode 8N (at substantially the same position as the movable contact electrode 8N) in a plan view from the upper side to the lower side in FIG. It is formed to have approximately the same area as the electrode 8N. Further, the opposing metal film 8aN is not in contact with other metal films and is electrically independent.

The base substrate 2N has a substantially rectangular shape in plan view when viewed from the upper side to the lower side in FIG. A depression 7N (concave portion) having a substantially circular shape in plan view is formed in the substantially center portion in plan view. In the base substrate 2N, a portion around the depression 7N formed on the upper surface 20Na of the base substrate 2N in plan view is thicker than a portion of the depression 7N. In the base substrate 2N, a portion (thin wall portion) 2Na of the recess 7N and a portion (thick wall portion) 2Nb that is thicker than the thin wall portion 2Na are integrally formed of the same material.

The depression 7N (concave portion) can be formed, for example, by wet etching the formation region of the depression 7N on the upper surface 20Na of the base substrate 2N using photolithography technology.

In the recess 7N formed by wet etching the formation region of the recess 7N on the upper surface 20Na of the base substrate 2N using photolithography, in the cross-sectional part shown in the cross-sectional view in FIG. The side surface is inclined (angle of inclination≠90°) so as to be located on the negative direction side of the Z' axis (right side in FIG. 19) as it moves away from the upper surface of the thick portion 2Nb. In addition, in the cross-sectional area shown in FIG. 19, the inner side surface of the thick wall portion 2Nb is located on the negative direction side of the Z' axis (to the right side in FIG. 19) as it moves away from the upper surface of the thick wall portion 2Nb. (angle of inclination ≠ 90°).

On the upper surface 20Na of the base substrate 2N, there are a base-side fixed contact electrode 11N forming a fixed contact of the pressure switch 1N, and a base-side second bonding electrode 12N integrally formed with the base-side fixed contact electrode 11N. , a base-side first bonding electrode 13N that is not in contact with either the base-side fixed contact electrode 11N or the base-side second bonding electrode 12N is formed. In the cross section shown in FIG. 19, the electrode formed by integrally forming the base side fixed contact electrode 11N and the base side second bonding electrode 12N is connected to the upper surface of the thick part 2Nb of the base substrate 2N. It is bent at an obtuse angle at the boundary between the inner side surface of the base substrate 2Nb and the upper surface of the thin section 2Na (the portion surrounded by the dotted line RN1 in FIG. 19). 19) is bent at an obtuse angle. For example, the shape of the base-side fixed contact electrode 11N, the base-side second bonding electrode 12N, and the base-side first bonding electrode 13N at the upper surface of the thick portion 2Nb and the upper surface of the thin portion 2Na of the base substrate 2N is , the shapes of the base-side fixed contact electrode 11H, the base-side second bonding electrode 12H, and the base-side first bonding electrode 13H at the upper surface of the thick portion and the upper surface of the thin portion of the base substrate 2H are approximately the same. be. Further, for example, the base side fixed contact electrode 11N has the same film configuration as the base side fixed contact electrode 11H of the ninth embodiment, and the base side second bonding electrode 12N has the same film configuration as the base side fixed contact electrode 11H of the ninth embodiment. The base-side first bonding electrode 13N has the same film configuration as the base-side first bonding electrode 13H of the ninth embodiment.

In this embodiment, the first interlayer connection conductor 15Ha formed on the base substrate 2N connects the first external connection electrode 14Ha formed on the lower surface 20Nb and the base-side first bonding electrode 13N formed on the upper surface 20Na. Connecting. Further, the second interlayer connection conductor 15Hb formed on the base substrate 2N connects the second external connection electrode 14Hb formed on the lower surface 20Nb and the base-side second bonding electrode 12N formed on the upper surface 20Na.

Note that in this embodiment, as in the ninth embodiment, the top layer of the Au film of the first bonding electrode 9N on the lid substrate 3N side and the first bonding electrode 13N on the base substrate 2N side are finally separated. The top layer Au film is diffusion bonded (Au-Au bond), and the top layer Au film of the second bonding electrode 10F on the lid substrate 3N side and the top layer of the second bonding electrode 12N on the base substrate 2N side are bonded. By diffusion bonding with the Au film (Au--Au bond), an airtight space is formed.

When the pressure switch 1N in FIG. 19(a) is placed in a vacuum, it becomes an open loop (broken wire) and no current flows, similar to the pressure switch 1H in the ninth embodiment. On the other hand, when the degree of vacuum in the space in which the pressure switch 1N shown in FIG. state.

According to this embodiment, the same effects as the above-described ninth embodiment are achieved. Further, stress acting on the boundary between the diaphragm 5N and the thick portion 6N in the lid substrate 2N can be alleviated. Further, since the electrode formed by integrally forming the base-side fixed contact electrode 11N and the base-side second bonding electrode 12N has a gentle bend, it is difficult to break the wire.

Incidentally, the inclination (inclination angle≠90°) of the outer side surface and inner side surface of each substrate (base substrate, lid substrate) is different from that of each substrate (base substrate, lid substrate) in the tenth to fourteenth embodiments. (substrate, cover substrate, upper substrate, etc.).

≪Sixteenth embodiment≫
A pressure switch 1P according to a sixteenth embodiment of the present invention will be described with reference to FIG. 20. The lid substrate 3P of the pressure switch 1P of the sixteenth embodiment has a different shape from the lid substrate 3N of the pressure switch 1N of the fifteenth embodiment. In the 16th embodiment, parts having the same configuration as in the 9th or 15th embodiment are given the same reference numerals as in the 9th or 15th embodiment, and the description thereof will be omitted.

The pressure switch 1P is configured to include a base substrate 2N and a lid substrate 3P whose lower surface 30Pb is arranged to face the upper surface 20Na of the base substrate 2N. The same material as the base substrate 2H and lid substrate 3H of the ninth embodiment can be used as the material of the base substrate 2N and the lid substrate 3P, and in this embodiment, the base substrate 2N and the lid substrate 3P are made of AT Composed of cut crystals. The coordinate axes in FIG. 20 represent the crystal axes of AT-cut crystal, the X-axis is the electrical axis, the Y-axis is the mechanical axis, and the Z'-axis is the optical axis.

The lid board 3P has a substantially rectangular shape when viewed from the top to the bottom in FIG. A recess 4P (concave portion) is formed at approximately the center in plan view. The recesses 4P are, in order from the upper surface 30Pa side of the lid substrate 3P, a second recess 4P2 formed on the upper surface 30Pa of the lid substrate 3P and having a substantially circular shape in plan view, and a second recess 4P2 formed on the bottom surface of the second recess 4P2 in plan view. The first depression 4P1 has a substantially circular shape and is smaller in size in plan view than the second depression 4P2.

Thereby, the lid substrate 3P is configured to include a thin diaphragm 5P and a thick portion 6P that is thicker than the thin diaphragm 5P around the thin diaphragm 5P in plan view. The thick part 6P includes, in order from the outer side surface of the lid substrate 3P, a second thick part 6P2 and a first thick part 6P1, which is thinner than the second thick part 6P2 and thicker than the diaphragm 5P. configured to include. In this way, the thick portion 6P increases in thickness in two steps from the center side of the lid substrate 3P toward the outer side surface of the lid substrate 3P in plan view.

The depression 4P (concave portion) can be formed, for example, by wet etching the formation region of the depression 4P on the upper surface 30Pa of the lid substrate 3P using photolithography technology.

In the thick portion 6G related to the depression 4G formed by wet etching the formation region of the depression 4G on the upper surface 30Pa of the lid substrate 3P using photolithography technology, the thickness is The outer side surface of the second thick wall portion 6P2 constituting the wall portion 6P is inclined so as to be located on the negative direction side of the Z′ axis (to the right side in FIG. 20) as it moves away from the upper surface of the second thick wall portion 6P2. There is. Further, in the cross-sectional area shown in FIG. 20, the inner side surface of the second thick part 6P2 constituting the thick part 6P moves in the negative direction of the Z' axis as it moves away from the upper surface of the second thick part 6P2. 20 (right side in FIG. 20). In addition, in the cross-sectional area shown in FIG. 20, the inner side surface of the first thick part 6P1 constituting the thick part 6P moves in the negative direction of the Z' axis as it moves away from the upper surface of the first thick part 6P1. 20 (right side in FIG. 20).

In the lid substrate 3P, the diaphragm 5P and the thick portion 6P including the first thick portion 6P1 and the second thick portion 6P2 are integrally molded from the same material.

On the lower surface 30Pb of the lid substrate 3P, a lid-side movable contact electrode 8P forming a movable contact of the pressure switch 1N, and a lid-side first bonding electrode 9P integrally formed with the lid-side movable contact electrode 8P are provided. , a lid-side second bonding electrode 10P that is not in contact with either the lid-side movable contact electrode 8P or the lid-side first bonding electrode 9P is formed. For example, the lid-side movable contact electrode 8P has the same shape and the same membrane structure as the lid-side movable contact electrode 8H of the ninth embodiment, and the lid-side first bonding electrode 9P has the same shape and the same film configuration as the lid-side movable contact electrode 8H of the ninth embodiment. It has the same shape and the same film structure as the first bonding electrode 9H, and the lid-side second bonding electrode 10P has the same shape and the same film structure as the lid-side second bonding electrode 10H of the ninth embodiment. .

A counter metal film 8aP that pairs with the movable contact electrode 8P is formed on the upper surface 5Pa of the diaphragm 5P of the lid substrate 3P. The opposing metal film 8aP has the same structure and the same thickness as the movable contact electrode 8P (the thickness in the vertical direction in FIG. 20(a) is the same). In addition, the thickness of each metal film is the same as the thickness of the corresponding metal film of the movable contact electrode 8P. In addition, the opposing metal film 8aP substantially overlaps the movable contact electrode 8P (at substantially the same position as the movable contact electrode 8N) in a plan view from the upper side to the lower side in FIG. It is formed to have approximately the same area as the electrode 8N. Further, the opposing metal film 8aP is not in contact with other metal films and is electrically independent.

Note that, in this embodiment, as in the ninth embodiment, the top layer of the Au film of the first bonding electrode 9P on the lid substrate 3P side and the first bonding electrode 13N on the base substrate 2N side are ultimately separated. The top layer Au film is diffusion bonded (Au-Au bond), and the top layer Au film of the second bonding electrode 10P on the lid substrate 3P side and the top layer of the second bonding electrode 12N on the base substrate 2N side are bonded. By diffusion bonding with the Au film (Au--Au bond), an airtight space is formed.

When the pressure switch 1P in FIG. 20(a) is placed in a vacuum, it becomes an open loop (broken wire) and no current flows, similar to the pressure switch 1H in the ninth embodiment. On the other hand, when the degree of vacuum in the space in which the pressure switch 1P shown in FIG. state.

According to this embodiment, the same effects as the above-described ninth embodiment and the same effects as the above-described fifteenth embodiment are achieved. Further, the thick portion 6P is configured to be a first thick portion 6P1 and a second thick portion 6P2 thicker than the first thick portion 6P1 in order from the diaphragm 5P side. The thickness of the lid substrate 3P is prevented from changing rapidly at the boundary portion where the 1-thick portion 6G1 and the diaphragm 5P are adjacent to each other. By doing so, it is possible to relieve stress on the boundary portion where the diaphragm 5P and the first thick portion 6P1 of the thick portion 6P adjoin.

Note that in the sixteenth embodiment, the thick portion 6P has a structure in which the thickness increases in two steps from the diaphragm 5P side toward the outer side surface of the lid substrate 3P, but the thick portion 6P is not limited to this. Alternatively, the thick portion may have a structure in which the thickness increases in three or more steps from the diaphragm side toward the outer side surface of the lid substrate.

Note that the content of increasing the thickness in multiple stages from the diaphragm side toward the outer side of the substrate (lid substrate) applies to substrates having a diaphragm such as the tenth to fourteenth embodiments. It is possible.

(ratio of diaphragm diameter to thickness)
Next, a particularly preferable ratio of the diameter to the thickness of the diaphragm 5H of the pressure switch 1H will be described with reference to FIG. 21. Note that the particularly preferable ratio of the diameter to the thickness of the diaphragm 5H described below is applicable to the tenth to sixteenth embodiments and their modifications.

The diameter of the diaphragm 5H, which is approximately circular in plan view when viewed from the top to the bottom of FIG. 22, which is a cross-sectional view of the diaphragm 5H, is D, and the thickness of the diaphragm 5H (vertical height in the cross-sectional view shown in FIG. 22) is Let s) be t. In this example, the diameter D is 0.7 mm or more and 0.9 mm or less (0.7 mm≦D≦0.9 mm), the thickness t is 5 μm or more and 10 μm or less (5 μm≦t≦10 μm), and the diaphragm 5H is Set the diameter D and thickness t. Therefore, if the minimum value of the diameter D is written as Dmin and the maximum value as Dmax, and the minimum value of the thickness t is written as tmin and the maximum value as tmax, then D/t should be greater than or equal to Dmin/tmax and less than or equal to Dmax/tmin. The diameter D and thickness t of the diaphragm 5H are set as follows. In this example, Dmin/tmax=0.7/0.01=70 and Dmax/tmin=0.9/0.005=180, so D/t should be 70 or more and 180 or less ( 70≦D/t≦180), and the diameter D and thickness t of the diaphragm 5H are set.

If D/t is less than the lower limit value "70" (D/t<70), there is a risk that the strength of the diaphragm 5H may become insufficient. Further, if D/t exceeds the upper limit value "180" (D/t>180), there is a possibility that the deformation of the diaphragm 5H in response to pressure becomes small and the pressure switch 1H will no longer function as a switch. On the other hand, if the diameter D and thickness t of the diaphragm 5H are set so that D/t is greater than or equal to the lower limit value "70" and less than or equal to the upper limit value "180" (70≦D/t≦180), as described above, It is possible to suppress the occurrence of problems.

(Concave shape when each substrate is made of glass)
Next, with reference to FIG. 22, the shapes of the

recesses

4H and 7H will be described when the base substrate 2H and lid substrate 3H of the pressure switch 1H according to the ninth embodiment are glass substrates. Note that each configuration is the same as in the ninth embodiment, so the explanation will be omitted by giving the same reference numerals.

If the crystal structure of the substrate is anisotropic, the amount of etching may increase in a particular direction, and if the substrate is formed of such a material, the shape of the diaphragm 5H will become unstable. On the other hand, since glass is an amorphous and isotropic material, when the base substrate 2H and lid substrate 3H are glass substrates and the

recesses

4H and 7H are formed by etching, the amount of etching (removal amount) becomes uniform regardless of direction. As a result, the

depressions

4H and 7H become approximately bowl-shaped as shown in FIG. 22, and the shape symmetry of the diaphragm 5H is improved.

In addition, since the

depressions

4H and 7H are bowl-shaped, when the diaphragm 5H is deformed, the stress acting on the boundary between the thick part 6H and the diaphragm 5H is evenly distributed, so that the highly durable pressure switch 1H can be provided.

In addition, various design changes can be made to the configurations described above in the ninth to sixteenth embodiments.

Furthermore, the contents described in the ninth to sixteenth embodiments and the modifications of the ninth to sixteenth embodiments may be combined as appropriate.

≪Additional note 2≫
Supplementary note 2 according to the ninth to sixteenth embodiments and modifications of the ninth to sixteenth embodiments is that the movable contact and the fixed contact or other The present invention relates to a pressure switch in which a movable contact contacts or separates.

Conventionally, there have been pressure switches in which a movable contact and a fixed contact come into contact with or separate from each other by deformation of a diaphragm due to changes in external pressure. For example, there is a pressure switch disclosed in Japanese Patent Laid-Open No. 2001-176365.

In the pressure switch disclosed in Japanese Unexamined Patent Publication No. 2001-176365, a first substrate having a diaphragm that can be deformed by an external force and a second substrate are overlapped, and the first substrate and the second substrate are stacked on top of each other. An airtight space is formed between the device and the substrate, and a contact mechanism arranged within the airtight space is opened and closed based on the deformation of the diaphragm. In the contact mechanism, a movable contact is provided on the surface of the first substrate facing the second substrate at a position corresponding to the diaphragm, and a movable contact is provided on the surface of the second substrate facing the first substrate. A fixed contact is provided opposite to the diaphragm and comes into contact with the movable contact based on the deformation of the diaphragm. Silicon is used as a material constituting the first substrate having the diaphragm, and gold is used as a material constituting the movable contact provided on the surface of the first substrate facing the second substrate.

By the way, the electrode film constituting the movable contact is formed on the first substrate at high temperature, and the pressure switch is used at room temperature. At room temperature, the coefficient of thermal expansion of silicon used as the material constituting the first substrate with the diaphragm is different from that of gold used as the material constituting the movable contact. Stress is generated and the diaphragm and movable contact become warped (deflected). Therefore, due to changes in the external pressure of the pressure switch, the movable contact and the fixed contact cannot be switched between the contact state and the non-contact state, resulting in a problem that the desired function of the pressure switch cannot be realized. It can happen.

In view of the above-mentioned problems, the objective of appendix 2 is to provide a pressure switch that can suppress warpage (deflection) of the diaphragm when no external pressure is applied to the pressure switch at room temperature.

In order to achieve the above object, the pressure switch according to Supplementary Note 2 includes a first substrate and a second substrate that forms an airtight space between the first substrate and the first substrate by being joined to the first substrate. a diaphragm formed at a position corresponding to the airtight space and deformed by external pressure changes; and a diaphragm disposed on the diaphragm and movable. a first contact forming a contact; and a second contact facing the first contact at a predetermined distance and forming a fixed contact or another movable contact; The electrical connection is switched by the first contact and the second contact coming into contact or separating, and the diaphragm has one main surface and the other main surface facing each other, and the one main surface A contact electrode film, which is an electrode film constituting the first contact, is formed on one surface, and a counter metal film, which is a metal film paired with the contact electrode film, is formed on the other main surface. It is characterized by

According to this configuration, by forming a contact electrode film constituting the first contact on one main surface of the diaphragm and forming a counter electrode film on the other main surface, the coefficient of thermal expansion of the diaphragm and the contact electrode film are formed on the other main surface. The stress generated between the diaphragm and the contact electrode film based on the difference in the thermal expansion coefficient of the diaphragm and the opposing metal film is This can be offset by the stress generated between This makes it possible to suppress warpage (deflection) of the diaphragm when no external pressure is applied to the pressure switch at room temperature.

Furthermore, the contact electrode film may be a metal film, and the opposing metal film may have the same configuration as the contact electrode film.

According to this configuration, the difference between the thermal expansion coefficient of the diaphragm on one main surface side of the diaphragm and the thermal expansion coefficient of the contact electrode film, and the difference between the thermal expansion coefficient of the diaphragm and the opposing metal on the other main surface side of the diaphragm. By making the difference with the coefficient of thermal expansion of the membranes the same, it is possible to improve the balance between the stress generated on one main surface side of the diaphragm and the stress generated on the other main surface side of the diaphragm. Thereby, warping (deflection) of the diaphragm can be more effectively suppressed when no external pressure is applied to the pressure switch at room temperature.

Furthermore, the contact electrode film and the opposing metal film may have the same thickness and the same area in plan view.

According to this configuration, by increasing the symmetry between the contact electrode film on one main surface side of the diaphragm and the opposing metal film on the other main surface side of the diaphragm, stress generated on one main surface side of the diaphragm is increased. It is possible to improve the balance between the stress generated on the other main surface side of the diaphragm and the stress generated on the other main surface side of the diaphragm. Thereby, warping (deflection) of the diaphragm can be more effectively suppressed when no external pressure is applied to the pressure switch at room temperature.

Furthermore, the opposing metal film may be electrically independent.

According to this configuration, there is no need to form a lead wiring extending from the opposing metal film on the diaphragm, so that the contact electrode film on one main surface side of the diaphragm and the opposing metal film on the other main surface side of the diaphragm are flat. As a result, the symmetry between the contact electrode film on one main surface side of the diaphragm and the opposing metal film on the other main surface side of the diaphragm can be improved, and the area of the diaphragm It is possible to improve the balance between the stress generated on one main surface side and the stress generated on the other main surface side of the diaphragm. Thereby, warping (deflection) of the diaphragm can be more effectively suppressed when no external pressure is applied to the pressure switch at room temperature.

Furthermore, the diaphragm may be made of crystal or glass.

According to this configuration, when the diaphragm is made of crystal, when the diaphragm is made thin, the sensitivity as a pressure switch is improved, but the diaphragm lacks strength and is easily damaged. On the other hand, when the thickness of the diaphragm is increased, the strength can be ensured, but the sensitivity as a pressure switch decreases. Therefore, in order to satisfy sensitivity and strength, it is necessary to keep the thickness of the diaphragm within a predetermined range. It is known that the thickness of crystal depends on the resonant frequency, and by controlling the resonant frequency of the diaphragm to a value corresponding to the desired thickness, a diaphragm with a desired thickness can be easily formed. Therefore, a high quality pressure switch with an optimized balance between strength and sensitivity can be formed. Further, by using crystal as the material for forming the diaphragm, a large number of pressure switches can be manufactured at once using, for example, wet etching or photolithography technology, and an inexpensive pressure switch can be provided.

Furthermore, when the diaphragm is made of glass, glass is an amorphous and isotropic material, so for example, when the diaphragm is formed by etching a glass substrate, the amount of etching is uniform regardless of direction. It is possible to form a diaphragm with excellent shape symmetry. Furthermore, since glass has a smaller Young's modulus than quartz, it is relatively easier to deform than quartz, making it easier to ensure strength.

According to Appendix 2, by forming a contact electrode film constituting the first contact on one main surface of the diaphragm and forming a counter electrode film on the other main surface, the coefficient of thermal expansion of the diaphragm and the contact point can be adjusted. The stress generated between the diaphragm and the contact electrode film based on the difference in the thermal expansion coefficient of the diaphragm and the opposing metal film is This can be offset by the stress generated between This makes it possible to suppress warpage (deflection) of the diaphragm when no external pressure is applied to the pressure switch at room temperature.

Supplementary note 2 is widely applicable to pressure switches in which a movable contact and a fixed contact or other movable contacts come into contact with each other or separate from each other due to deformation of the diaphragm due to external pressure changes.

The present invention is widely applicable to various pressure switches that utilize deformation of a diaphragm.

1: Pressure switch 2: Base board 3: Lid board 5: Diaphragm 8: Lid side movable contact electrode 11: Base side fixed contact electrode

Claims

a first substrate;
a second substrate that forms an airtight space between the first substrate and the first substrate;
a diaphragm formed in at least one of the first substrate and the second substrate at a position corresponding to the airtight space and deformed by external pressure changes;
a first contact disposed on the diaphragm and forming a movable contact;
a second contact that faces the first contact at a predetermined distance and serves as a fixed contact or another movable contact;
Due to the deformation of the diaphragm, the first contact and the second contact contact or separate, thereby switching the electrical connection,
A pressure switch characterized in that the diaphragm is made of crystal.
a first substrate;
a second substrate that forms an airtight space between the first substrate and the first substrate;
a diaphragm formed in at least one of the first substrate and the second substrate at a position corresponding to the airtight space and deformed by external pressure changes;
a first contact disposed on the diaphragm and forming a movable contact;
a second contact that faces the first contact at a predetermined distance and serves as a fixed contact or another movable contact;
Due to the deformation of the diaphragm, the first contact and the second contact contact or separate, thereby switching the electrical connection,
A pressure switch, wherein the diaphragm is made of glass.
The pressure switch according to claim 1 or 2, wherein the first substrate and the second substrate are made of the same material.
The diaphragm is formed by making a part of the first substrate and/or the second substrate on which the diaphragm is formed thinner than other parts, and The pressure switch according to claim 1 or 2, wherein one part and the other part are integrally formed.
The pressure switch according to claim 1 or 2, wherein the first substrate and the second substrate have the same thickness.
3. The pressure switch according to claim 1, wherein the first substrate and the second substrate are joined via a metal film.