JP2018054457A - Mechanical quantity sensor and method of manufacturing dynamic quantity sensor - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a mechanical quantity sensor that hardly gets out of order.SOLUTION: There is provided a mechanical quantity sensor comprising: a thin film which has conductivity on a first surface and changes its shape with external force; a first structure arranged on the first surface of the thin film; a second structure covering an upper surface and a side face of the first structure and including a region in which a surface shape of a part covering a corner part connecting the upper surface and side face to each other is rounder than the corner part; and an electrode provided opposite the first surface of the thin film and forming a capacity part with the thin film. In the mechanical quantity sensor, one of the first structure and second structure has compressive stress and the other has tensile stress.SELECTED DRAWING: Figure 1

Description

  The present disclosure relates to a mechanical quantity sensor and a method for manufacturing a mechanical quantity sensor.

  A mechanical quantity sensor that detects an absolute value of an external force (hydraulic pressure, atmospheric pressure, vacuum degree) that changes from moment to moment is widely used in many industrial fields in order to precisely control an apparatus. In particular, as a mechanical quantity sensor using a diaphragm, a small mechanical quantity sensor has been developed. For example, Patent Document 1 discloses a technique for measuring pressure from a capacitance value formed by a diaphragm and a detection electrode provided to face the diaphragm. In the mechanical quantity sensor disclosed in Patent Document 1, when a large pressure is applied, the diaphragm may collide with the detection electrode and may not come off (this phenomenon may be referred to as a sticking phenomenon). Therefore, an anti-sticking film (hereinafter sometimes referred to as a stopper) is disposed on the diaphragm so that the diaphragm and the detection electrode do not directly contact each other, and the diaphragm and the detection electrode sandwich the stopper. Attempts have been made to reduce the contact area.

JP 2009-258088 A

  However, depending on the shape of the stopper, problems such as dust generation due to the breakage of the stopper and short-circuit between electrodes may occur, and there is a concern that the mechanical quantity sensor may break down.

  In view of such a problem, an object of the embodiment of the present disclosure is to provide a mechanical quantity sensor that is less likely to fail.

  According to an embodiment of the present disclosure, a thin film having conductivity on at least a first surface and changing a shape according to an external force, a first structure disposed on a first surface of the thin film, and a first structure A second structure including a region covering the upper surface and the side surface and covering the corner portion connecting the upper surface and the side surface and having a region that is rounder than the corner portion, and the first surface of the thin film A mechanical quantity sensor is provided that includes a thin film and an electrode that forms a capacitor.

  In the mechanical quantity sensor, one of the first structure and the second structure may have a compressive stress, and the other may have a tensile stress.

  In the mechanical quantity sensor, the second structure body may have an inorganic insulating layer on the surface.

  In the mechanical quantity sensor, the second structure may have a flat portion on a surface surrounded by a rounded region.

  In the mechanical quantity sensor, the first structure may include at least a first layer disposed on the first surface and a second layer disposed on a part of the upper surface on the first layer.

  In the mechanical quantity sensor, a plurality of first structures may be provided, a plurality of second structures may be provided, and one second structure may cover only one first structure.

  In the mechanical quantity sensor, there may be a plurality of first structures and a single second structure, and the plurality of first structures may be covered.

  In the mechanical quantity sensor, there are a plurality of first structures, a plurality of second structures, and the number of first structures covered by the second structures arranged at the first position on the first surface. The number of the first structures covered by the second structures arranged at the second position on the first surface may be different.

  According to an embodiment of the present disclosure, a first region of a second layer of a stacked body including a substrate, a first layer disposed on the substrate, and a conductive second layer disposed on the first layer. The first structure is formed in the first region of the second layer, the second structure is formed so as to cover the upper surface and the side surface of the first structure, and the electrode is formed. The first substrate and the second substrate are joined so as to form a space between the electrode of the second substrate on which is formed and the first region of the second layer, and the first layer is used as an etching stopper. A method for manufacturing a mechanical quantity sensor is provided, in which a second region of a substrate corresponding to at least a part of the region is etched, and the second region of the first layer is etched using the second layer as an etching stopper.

  In the manufacturing method of the mechanical quantity sensor, the second structure may be formed by a CVD method.

  In the manufacturing method of the mechanical quantity sensor, the second structure may be formed by a PVD method.

  According to an embodiment of the present disclosure, it is possible to provide a mechanical quantity sensor that is unlikely to fail.

It is sectional drawing explaining the mechanical quantity sensor which concerns on one Embodiment of this indication, and the enlarged view of a one part area | region. It is a top view explaining a physical quantity sensor concerning one embodiment of this indication. It is a bottom view explaining a physical quantity sensor concerning one embodiment of this indication. It is sectional drawing explaining the mechanical quantity sensor which concerns on one Embodiment of this indication. It is sectional drawing explaining the mechanical quantity sensor which concerns on one Embodiment of this indication. It is sectional drawing explaining the manufacturing method of the mechanical quantity sensor which concerns on one Embodiment of this indication. It is sectional drawing explaining the manufacturing method of the mechanical quantity sensor which concerns on one Embodiment of this indication. It is sectional drawing explaining the manufacturing method of the mechanical quantity sensor which concerns on one Embodiment of this indication. It is sectional drawing explaining the manufacturing method of the mechanical quantity sensor which concerns on one Embodiment of this indication. It is sectional drawing explaining the manufacturing method of the mechanical quantity sensor which concerns on one Embodiment of this indication. It is sectional drawing explaining the manufacturing method of the mechanical quantity sensor which concerns on one Embodiment of this indication. It is sectional drawing explaining the manufacturing method of the mechanical quantity sensor which concerns on one Embodiment of this indication. It is sectional drawing explaining the manufacturing method of the mechanical quantity sensor which concerns on one Embodiment of this indication. It is sectional drawing explaining the manufacturing method of the mechanical quantity sensor which concerns on one Embodiment of this indication. It is sectional drawing explaining the manufacturing method of the mechanical quantity sensor which concerns on one Embodiment of this indication. It is sectional drawing explaining the manufacturing method of the mechanical quantity sensor which concerns on one Embodiment of this indication. It is sectional drawing explaining the manufacturing method of the mechanical quantity sensor which concerns on one Embodiment of this indication. It is sectional drawing explaining the manufacturing method of the mechanical quantity sensor which concerns on one Embodiment of this indication. It is sectional drawing explaining the manufacturing method of the mechanical quantity sensor which concerns on one Embodiment of this indication. It is sectional drawing explaining the mechanical quantity sensor which concerns on one Embodiment of this indication, and the enlarged view of a one part area | region. It is a top view explaining a physical quantity sensor concerning one embodiment of this indication. It is sectional drawing explaining the mechanical quantity sensor which concerns on one Embodiment of this indication, and the enlarged view of a one part area | region. It is a top view explaining a physical quantity sensor concerning one embodiment of this indication. It is a top view explaining a physical quantity sensor concerning one embodiment of this indication. It is sectional drawing explaining the mechanical quantity sensor which concerns on one Embodiment of this indication, and the enlarged view of a one part area | region. It is sectional drawing explaining the mechanical quantity sensor which concerns on one Embodiment of this indication, and the enlarged view of a one part area | region. It is sectional drawing explaining the mechanical quantity sensor which concerns on one Embodiment of this indication, and the enlarged view of a one part area | region. It is sectional drawing explaining the mechanical quantity sensor which concerns on one Embodiment of this indication, and the enlarged view of a one part area | region. It is a top view explaining a physical quantity sensor concerning one embodiment of this indication. It is a top view explaining a physical quantity sensor concerning one embodiment of this indication.

  Hereinafter, a mechanical quantity sensor and a manufacturing method of the mechanical quantity sensor according to each embodiment of the present disclosure will be described in detail with reference to the drawings. In addition, each embodiment shown below is an example of embodiment of this indication, Comprising: This indication is limited to these embodiment and is not interpreted. Note that in the drawings referred to in the present embodiment, the same portion or a portion having a similar function is denoted by the same reference symbol or a similar reference symbol (a reference symbol simply including A, B, etc. after a number) and repeated. The description of may be omitted. In addition, the dimensional ratio in the drawing may be different from the actual ratio for convenience of explanation, or a part of the configuration may be omitted from the drawing.

<First Embodiment>
(1-1. Configuration of mechanical quantity sensor)
A cross-sectional view of the mechanical quantity sensor 100 is shown in FIG. As shown in FIG. 1A, the mechanical quantity sensor 100 includes a substrate 110, an insulating layer 120, a conductive layer 130, a thin film 135, a first structure 140, a second structure 150, a substrate 200, an electrode 210, and an electrode 220. , Electrode 230, electrode 240, electrode 250, and electrode 260.

A silicon substrate is used as the substrate 110. For the insulating layer 120, silicon oxide, silicon nitride, hafnium oxide, aluminum oxide, or the like is used. A semiconductor material is used for the conductive layer 130, but a metal material or the like may be used. For example, when silicon (Si) is used for the conductive layer 130, boron (B), aluminum (Al), phosphorus (P), arsenic (As), or the like is large in the silicon (for example, 10 ¹⁸ atoms / cm ³ to 10 ^{by 20} atoms / cm ³ or so) including, it may have conductivity. The substrate 110 and the insulating layer 120 have an opening in the region 180.

  The thin film 135 is provided as a portion corresponding to the region 180 of the conductive layer 130. The thin film 135 has a thickness of about 1 μm to 100 μm and has flexibility. The thin film 135 has conductivity on at least the first surface 135A (upper surface).

  A plurality of first structures 140 are provided on the first surface 135 </ b> A of the thin film 135. The first structure 140 may be a conductor material (metal or the like), a semiconductor material, or an insulator material. The insulator material may be an organic insulator material or an inorganic insulator material.

  A plurality of second structures 150 are provided on the thin film 135 and the first structure 140. FIG. 1B shows an enlarged view of the region 105. As shown in FIG. 1B, the second structure 150 is provided so as to cover the upper surface 140A and the side surface 140B of the first structure 140. Note that one second structure 150 may be provided so as to cover only one first structure 140. The second structure 150 includes a region 150C that is rounder than the corner portion 140C in the surface shape of the portion covering the corner portion 140C that connects the upper surface 140A and the side surface 140B. The second structure 150 may have a flat portion on the surface surrounded by the rounded region 150C. The second structure 150 may have an inorganic insulating layer on the surface. For example, a silicon oxide film may be used for the second structure 150, or an oxide film may be provided by oxidizing the surface of a copper (Cu) film. Note that one of the first structure 140 and the second structure 150 may have a compressive stress, and the other may have a tensile stress. For example, the first structure 140 may have a compressive stress, and the second structure 150 may have a tensile stress. Thereby, the stress generated by the first structure 140 and the second structure 150 is canceled out, and an excessive force is prevented from being applied to the thin film 135. The first structure 140 and the second structure 150 have a function as a stopper 160 for preventing sticking with the electrode 210.

  The electrode 210 is provided on the substrate 200. The electrode 210 is provided to face the first surface 135A of the thin film 135. A space 300 is provided between the thin film 135 and the electrode 210. The thin film 135, the electrode 210, and the space 300 form a capacitance part.

  The electrode 220 is provided on the same surface as the electrode 210 of the substrate 200. The electrode 250 is provided on the substrate 200 so as to face the electrode 210. The electrode 260 is provided on the substrate 200 so as to face the electrode 220. The electrode 230 is provided through the substrate 200 so as to connect the electrode 210 and the electrode 250. The electrode 240 is provided through the substrate 200 so as to connect the electrode 220 and the electrode 260.

  FIG. 2 is a view of the substrate 110 as viewed from the upper surface (substrate 200 side). FIG. 3 is a view of the substrate 200 as viewed from the lower surface (substrate 110 side). As shown in FIGS. 2 and 3, the thin film 135 and the electrode 210 have a circular shape. The first structure 140 and the second structure 150 have a circular shape and are arranged in a lattice shape.

(1-2. Description of operation of mechanical quantity sensor)
The mechanical quantity sensor 100 has a closed space 300, and the shape of the thin film 135 changes according to an external force (for example, pressure) 350. For example, as shown in FIG. 4, when the external force 350 is large, the thin film 135 bends upward (on the first surface 135A side). Further, as shown in FIG. 5, when the external force 350 is small, the thin film 135 is less bent upward (on the first surface 135A side). Due to the difference in the shape change of the thin film 135, the distance between the thin film 135 and the electrode 210 changes. Thereby, since the electrostatic capacitance between the thin film 135 and the electrode 210 changes, this is regarded as an electric signal, and an electric signal corresponding to an external force is obtained.

  Note that the thin film 135 has a circular shape. Thus, when an external force is applied evenly to the thin film 135, the thin film 135 is bent concentrically and the center portion is bent most greatly. In addition, when the thin film 135 is greatly bent upward due to a large external force, even if the second structure 150 collides with the electrode 210, the second structure 150 has the rounded region 150C. It is prevented that the two structures 150 are lost. Further, the second structure 150 is prevented from piercing the electrode 210. In addition, since the second structure 150 has a flat portion on the surface surrounded by the rounded region 150C, the second structure 150 comes into contact with the surface when the second structure 150 and the electrode 210 collide. Thereby, the impact at the time of a collision is disperse | distributed and an impact is relieved. In addition, since the second structure 150 has the inorganic insulating layer on the surface, the second structure 150 can be hardly fixed to the electrode 210. In addition, since the second structure 150 has the inorganic insulating layer on the surface, an electrical short circuit due to the contact between the thin film 135 and the electrode 210 is prevented. Thereby, the mechanical quantity sensor which is hard to break down can be provided.

(1-3. Manufacturing method of mechanical quantity sensor)
Next, a method for manufacturing the mechanical quantity sensor 100 shown in FIG. 1 will be described with reference to FIGS.

As shown in FIG. 6, the substrate 110, the insulating layer 120, and the conductive layer 130 have an SOI (Silicon on Insulator) structure. As a method for manufacturing an SOI substrate, for example, the substrate 110, the insulating layer 120, and the conductive layer 130 may be formed by a SIMOX (Separated by Implanted Oxygen) method in which a buried oxide film is formed by adding oxygen to a silicon substrate and performing high-temperature heat treatment. May be used. In addition, a smart oxide film is formed on one silicon substrate (sometimes called a bond wafer), hydrogen is added, it is bonded to the other silicon substrate (sometimes called a base wafer), and then peeled off after heat treatment. A cut method may be used. Alternatively, a bonding method may be used in which two silicon substrates with thermal oxide films are bonded together and adjusted to a specified thickness by polishing. Further, boron (B), aluminum (Al), phosphorus (P), arsenic (As), or the like is added to the conductive layer 130 as impurities. For example, arsenic (As) may be added to the conductive layer 130 at about 10 ¹⁸ atoms / cm ³ to 10 ²⁰ atoms / cm ³ . Accordingly, the conductive layer 130 can have conductivity.

  Further, the insulating layer 120 and the conductive layer 130 may be formed separately. For the insulating layer 120, silicon oxide, silicon nitride, hafnium oxide, aluminum oxide, or the like may be used. The insulating layer 120 may be formed by a thermal oxidation method, a CVD method, a PVD method, a coating method, or the like.

  For the conductive layer 130, silicon, germanium, silicon-germanium, silicon carbide, or the like may be used. The conductive layer 130 may be formed by a CVD method (such as a low pressure CVD method, an atmospheric pressure CVD method, a plasma CVD method) or a sputtering method.

  Next, as illustrated in FIG. 7, the region of the conductive layer 130 in the stacked body including the insulating layer 120 disposed on the substrate 110 and the conductive layer 130 having conductivity disposed on the insulating layer 120. The thin film 135 is formed by etching 170 until a predetermined film thickness is obtained. At this time, a hard mask using an insulating material such as silicon oxide may be used. A wet etching method is used for the etching. For example, when a single crystal silicon film having a plane orientation {100} is used for the conductive layer 130, the single crystal silicon film is crystal anisotropically etched with an alkaline solution. For example, TMAH (tetramethylammonium hydroxide) is used for the alkaline solution. The thin film 135 can have flexibility by being, for example, 1 μm to 100 μm.

  Next, as illustrated in FIG. 8, a film 139 to be the first structure 140 is formed over the conductive layer 130 and the thin film 135. The film 139 may be a conductor material (metal or the like), an organic insulator material, or an inorganic insulator material. The film 139 is formed by a CVD method, a PVD method (such as a sputtering method or a vacuum evaporation method), a printing method, or the like.

  Next, the first structure 140 is formed in the first region 170 of the thin film 135 by using a photolithography method and an etching method for the film 139 as shown in FIG.

  Next, as illustrated in FIG. 10, a film 149 to be the structure 150 is formed so as to cover the upper surface 140 </ b> A and the side surface 140 </ b> B of the first structure 140. The film 149 may be formed by a CVD method, a PVD method, a plating method, or the like. Next, the second structure 150 is formed as shown in FIG. 11 by etching the film 149 according to the pattern shape.

  For example, in the case where an aluminum film is formed as the film 139 by a sputtering method and then etched by a wet etching method to form the first structure 140, the corner portion 140C of the first structure 140 is sharp as shown in FIG. Have a different shape. However, by forming the film 149 so as to cover the first structure 140 by, for example, the CVD method, the second structure 150 can have a round region 150C as shown in FIG.

  Next, a through hole is formed in the substrate 200. As the substrate 200, alkali glass (soda glass substrate, borosilicate glass substrate, etc.) or non-alkali glass (quartz glass substrate, etc.) is used.

  The through hole can be formed by using, for example, a laser irradiation method (which can be referred to as a laser ablation method) for the substrate 200.

  Next, as shown in FIG. 14, the electrode 230 and the electrode 240 are formed in the through hole provided in the substrate 200. For the electrode 230 and the electrode 240, copper (Cu), silver (Ag), gold (Au), nickel (Ni), or the like is used. The electrode 230 and the electrode 240 may be formed by a combination of a sputtering method and a plating method, or may be formed by embedding a conductive resin. For example, for the electrode 230 and the electrode 240, a copper (Cu) film formed using a sputtering method and a plating method is used.

  Next, as shown in FIG. 15, the electrode 210 is formed on the substrate 200 so as to be in contact with the electrode 230. An electrode 220 is formed on the substrate 200 so as to be in contact with the electrode 240. For the electrode 210 and the electrode 220, gold (Au), nickel (Ni), copper (Cu), aluminum (Al), tungsten (W), or the like is used. Further, titanium (Ti), chromium (Cr), or the like is used as an adhesion layer with the substrate 200. The electrode 210 and the electrode 220 may be a single layer or a stacked layer. The electrodes 210 and 220 are formed by a PVD method (such as a sputtering method), a CVD method, a plating method, or a printing method. The electrodes 210 and 220 are processed into a predetermined shape by a photolithography method and an etching method.

  Next, as shown in FIG. 16, the first substrate 110 and the second substrate 200 are bonded so as to form a space 300 between the electrode 210 of the substrate 200 and the region 170 of the thin film 135. When the substrate 110 is a silicon substrate and the substrate 200 is an alkali glass substrate, the substrate 110 and the substrate 200 are bonded by using an anodic bonding method.

  Next, as shown in FIG. 17, the region 180 corresponding to at least a part of the region 170 of the substrate 110 is etched using the insulating layer 120 as an etching stopper. For example, when the substrate 110 is a silicon substrate and the insulating layer 120 is a silicon oxide film, the substrate 110 may be etched with an alkaline solution after a mask is formed on the lower surface of the substrate 110.

  Next, as shown in FIG. 18, the region 180 of the insulating layer 120 is etched using the thin film 135 as an etching stopper. For example, when the insulating layer 120 is a silicon substrate and the thin film 135 is a silicon film, the insulating layer 120 may be etched with a hydrofluoric acid solution.

  Next, as illustrated in FIG. 19, the electrode 250 is formed so as to be connected to the electrode 230 on the surface of the substrate 200 that faces the surface having the electrode 210. Similarly, an electrode 260 is formed so as to be connected to the electrode 240. The electrode 250 and the electrode 260 can be formed by a method similar to that of the electrode 210 and the electrode 220. The mechanical quantity sensor 100 can be manufactured by the above manufacturing method.

Second Embodiment
(2-1. Configuration of mechanical quantity sensor)
Next, mechanical quantity sensors having different structures will be described. In addition, about the structure, material, and method which were shown in 1st Embodiment, the description is used.

  20A is a cross-sectional view of the mechanical quantity sensor 1100, FIG. 20B is an enlarged view of the region 105, and FIG. 21 is a view of the substrate 110 of the mechanical quantity sensor 1100 viewed from the upper surface (substrate 200 side). As shown in FIGS. 20A, 20B, and 21, a plurality of first structures 140 are provided. One second structure 150 may be provided so as to cover the plurality of first structures 140. The second structure 150 may be used as it is after being formed without being processed by the photolithography method and the etching method. By having the said structure, it can have the same effect as the mechanical quantity sensor 100, shortening the manufacturing process of a mechanical quantity sensor.

<Third Embodiment>
(3-1. Configuration of mechanical quantity sensor)
Next, mechanical quantity sensors having different structures will be described. In addition, about the structure, material, and method which were shown in 1st Embodiment and 2nd Embodiment, the description is used.

  22A is a cross-sectional view of the mechanical quantity sensor 2100, FIG. 22B is an enlarged view of the region 105, and FIG. 23 is a top view of the mechanical quantity sensor 2100. The substrate 110 is viewed from the upper surface (substrate 200 side). The figure is shown. In the mechanical quantity sensor 2100, a plurality of first structures 140 and second structures 150 are provided. The number of first structures 140 covered by the second structure 150 may be different depending on the position. For example, as illustrated in FIG. 23, a second structure 150-1 that covers only the first structure 140-1 may be provided at the position 410, and the first structure 140-1 and the first structure 140-1 are provided at the position 420. A second structure 150-2 that covers the first structure 140-2, the first structure 140-3, and the first structure 140-4 may be provided.

  In addition, as illustrated in FIG. 24, a second structure 150-3 that covers the first structure 140-1 may be provided at a position 430. In the position 440, a second structure 150-4 that covers the first structure 140-1, the first structure 140-2, and the first structure 140-3 may be provided. At the position 450, a second structure 150-5 that covers the first structure 140-1, the first structure 140-2, the first structure 140-3, and the first structure 140-4 may be provided. . At the position 460, the second structure 150 covering the first structure 140-1, the first structure 140-2, the first structure 140-3, the first structure 140-4, and the first structure 140-5. -6 may be provided.

<Fourth embodiment>
(4-1. Configuration of mechanical quantity sensor)
Next, mechanical quantity sensors having different structures of the first structure 140 will be described. In addition, about the structure, material, and method which were shown in 1st Embodiment, 2nd Embodiment, and 3rd Embodiment, the description is used.

  FIG. 25A shows a cross-sectional view of the mechanical quantity sensor 3100 and FIG. 25B shows an enlarged view of the region 105. As shown in FIGS. 25A and 25B, the first structure 140 is disposed at least on the first layer 141 disposed on the first surface 135A and a part of the upper surface on the first layer 141. A second layer 143 may be included. The first layer 141 and the second layer 143 are covered with the second structure 150. The same material may be used for the first layer 141 and the second layer 143, or different materials may be used. By having the structure shown in FIGS. 25A and 25B, the region 150 of the second structure 150 is more easily rounded. Therefore, even when the second structure 150 collides with the electrode 210, the second structure 150, Both of the electrodes 210 are less likely to be damaged.

  FIG. 26A is a cross-sectional view of the mechanical quantity sensor 3101, and FIG. 26B is an enlarged view of the region 105. As shown in FIGS. 26A and 26B, the second structure 150 may include a structure 151 and a structure 153. The same material may be used for the structure 151 and the structure 153, or different materials may be used. The structure body 151 and the structure body 153 may each be provided by etching after film formation. Alternatively, the structure body 151 and the structure body 153 may be provided by forming two films to be the structure body 151 and the structure body 153 and then simultaneously etching the two films. By having the structure shown in FIGS. 26A and 26B, the region 150C of the second structure 150 is more likely to be rounded. Therefore, even when it collides with the electrode 210, the second structure 150, Both of the electrodes 210 are less likely to be damaged.

  27A and 27B are cross-sectional views of the mechanical quantity sensor 3102. FIG. As shown in FIGS. 27A and 27B, the first structure 140 may be a single layer or a stacked layer including the first layer 141 and the second layer 143 depending on the position. But you can.

  28A and 28B are cross-sectional views of the mechanical quantity sensor 3102. FIG. As shown in FIGS. 28A and 28B, the first structure 140 may be a single layer or a stacked layer including the first layer 141 and the second layer 143 depending on the position. Alternatively, the second structure 150 may cover only one first structure 140, or may cover a plurality of first structures 140. For example, the first structure 140 is a single layer in the central portion of the thin film 135, and the first structure 140 is a stacked layer including the first layer 141 and the second layer 143 in a region near the end of the thin film 135. In this case, the second structure 150 is more difficult to adhere to the electrode 210 because the height of the second structure 150 varies depending on the position. Thereby, it is possible to provide a mechanical quantity sensor that is more resistant to failure.

(Modification)
In the embodiment of the present disclosure, the example in which the first structures 140 are arranged in a lattice shape has been described, but the first structures 140 may be arranged concentrically as shown in FIG. Further, they may be arranged in a lattice or checkered pattern, may have a circular shape, may have a square shape as shown in FIG. 30, or may have a polygonal shape.

  105 ... region, 110 ... substrate, 120 ... insulating layer, 130 ... conductive layer, 135 ... thin film, 135A ... upper surface, 139 ... film, 140 ... first Structure, 140A ... upper surface, 140B ... side surface, 140C ... corner, 141 ... first layer, 143 ... second layer, 149 ... film, 150 ... structure , 150C ... region, 151 ... structure, 153 ... structure, 160 ... stopper, 170 ... region, 180 ... region, 200 ... substrate, 210 ... electrode 220 ... Electrode, 230 ... Electrode, 240 ... Electrode, 250 ... Electrode, 260 ... Electrode, 300 ... Space, 350 ... External force, 410 ... Position, 420 ... Position, 430 ... Position, 440 ... Position, 450 ... Position, 110 ... mechanical quantity sensor, 2100 ... mechanical quantity sensor, 3100 ... mechanical quantity sensor, 3101 ... mechanical quantity sensor, 3102 ... mechanical sensor

Claims (11)

A thin film having conductivity on at least the first surface and changing its shape in accordance with an external force;
A first structure disposed on the first surface of the thin film;
A second structure that covers an upper surface and a side surface of the first structure, and includes a region that is rounder than the corner in a surface shape of a portion that covers the corner connecting the upper surface and the side;
An electrode that is provided facing the first surface of the thin film and forms a capacitance portion with the thin film;
A mechanical quantity sensor. One of the first structure and the second structure has a compressive stress,
The other has tensile stress,
The mechanical quantity sensor according to claim 1. The second structure has an inorganic insulating layer on the surface,
The mechanical quantity sensor according to claim 1 or 2. The second structure has a flat portion on a surface surrounded by the rounded region.
The mechanical quantity sensor as described in any one of Claims 1 thru | or 3. The first structure includes at least a first layer disposed on the first surface and a second layer disposed on a part of an upper surface on the first layer.
The mechanical quantity sensor as described in any one of Claims 1 thru | or 4. The first structure is plural,
The second structure is plural,
One second structure covers only one first structure,
The mechanical quantity sensor according to any one of claims 1 to 5. A plurality of the first structures;
The number of the second structures is one, and a plurality of the first structures are covered.
The mechanical quantity sensor according to any one of claims 1 to 5. The first structure is plural,
The second structure is plural,
The number of the first structures covered by the second structures arranged at the first position on the first surface and the first structures covered by the second structures arranged at the second position on the first surface. Different from the number of structures,
The mechanical quantity sensor according to any one of claims 1 to 5. Of the laminate having a substrate, a first layer disposed on the substrate, and a conductive second layer disposed on the first layer, the first region of the second layer has a predetermined thickness. Etch until
Forming a first structure in the first region of the second layer;
Forming a second structure so as to cover an upper surface and a side surface of the first structure;
Bonding the first substrate and the second substrate so as to form a space between the electrode of the second substrate on which the electrode is formed and the first region of the second layer;
Etching a second region of the substrate corresponding to at least a portion of the first region using the first layer as an etching stopper,
Etching the second region of the first layer using the second layer as an etching stopper;
Manufacturing method of mechanical quantity sensor. The second structure is formed by a CVD method.
The manufacturing method of the mechanical quantity sensor of Claim 9. The second structure is formed by a PVD method.
The manufacturing method of the mechanical quantity sensor of Claim 9.

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