Sensor

Abstract

To provide a sensor that is capable of performing stable detection.SOLUTION: According to an embodiment, a sensor includes a structure. The structure includes a base layer, a first film, and a first layer. The first film includes at least one element selected from a group consisting of silicon and aluminum, and oxygen. Either cubic volume of the first layer or electric resistance of the first layer is changeable in accordance with a detection object around the structure. The first film includes a first film region, a second film region, and a third film region. The first layer is located between the base layer and the first film region in a first direction from the base layer to the first film region. In a second direction intersecting the first direction, the first layer is located between the second film region and the third film region.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] FIELD OF THE INVENTION An embodiment of the present invention relates to a sensor. [Background technology]

[0002] For example, stable detection is desired in sensors. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Application Publication No. 2019-56607 Summary of the Invention [Problem to be solved by the invention]

[0004] The embodiment provides a sensor capable of stable detection. [Means for solving the problem]

[0005] According to an embodiment, a sensor includes a structure. The structure includes a base layer, a first film, and a first layer. The first film includes at least one selected from the group consisting of silicon and aluminum, and oxygen. At least one of the volume and electrical resistance of the first layer is variable depending on a detection target around the structure. The first film includes a first film region, a second film region, and a third film region. The first layer is between the base layer and the first film region in a first direction from the base layer to the first film region. In a second direction intersecting the first direction, the first layer is between the second film region and the third film region. [Brief explanation of the drawings]

[0006] [Figure 1] 1A and 1B are schematic cross-sectional views illustrating the sensor according to the first embodiment. [Figure 2]FIG. 2 is a schematic cross-sectional view illustrating the sensor according to the second embodiment. [Figure 3] FIG. 3 is a schematic cross-sectional view illustrating a sensor according to the third embodiment. DETAILED DESCRIPTION OF THE INVENTION

[0007] Hereinafter, embodiments of the present invention will be described with reference to the drawings. The drawings are schematic or conceptual, and the relationship between the thickness and width of each part, the size ratio between parts, etc. are not necessarily the same as those in reality. Even when the same part is shown, the dimensions and ratios may be different depending on the drawing. In this specification and in each drawing, elements similar to those previously described with reference to the previous drawings are designated by the same reference numerals, and detailed descriptions thereof will be omitted where appropriate.

[0008] (First embodiment) 1A and 1B are schematic cross-sectional views illustrating the sensor according to the first embodiment. 1(a) and 1(b), a sensor 110 according to the embodiment includes a structure 18. The structure 18 includes a base layer 10B, a first film 11, and a first layer 31.

[0009] The first film 11 contains at least one selected from the group consisting of silicon and aluminum, and oxygen. The first film 11 may contain, for example, at least one selected from the group consisting of SiO2 and Al2O3. The first film 11 may contain, for example, SiAlO.

[0010] At least one of the volume of the first layer 31 and the electrical resistance of the first layer 31 can change depending on the detection target around the structure 18. For example, the detection target is a gas. For example, the detection target is hydrogen. The detection target may include at least one selected from the group consisting of hydrogen, hydrogen molecules, and hydrogen ions.

[0011] For example, the first layer 31 can capture a target substance (e.g., hydrogen). For example, the capture of the target substance into the first layer 31 increases the volume of the first layer 31. The change in volume may cause deformation of the structure 18. For example, the concentration of the target substance can be detected by detecting the deformation.

[0012] When the detection target is taken into the first layer 31, the electrical resistivity of the first layer 31 changes (for example, increases). This changes the electrical resistance of the first layer 31. By detecting the change in electrical resistance, the concentration of the detection target can be detected.

[0013] 1(a), the first film 11 includes a first film region 11a, a second film region 11b, and a third film region 11c. The first layer 31 is located between the base layer 10B and the first film region 11a in a first direction D1 from the base layer 10B to the first film region 11a.

[0014] The first direction D1 is defined as the Z-axis direction. One direction perpendicular to the Z-axis direction is defined as the X-axis direction. The direction perpendicular to the Z-axis direction and the X-axis direction is defined as the Y-axis direction.

[0015] 1(a), the first layer 31 is located between the second film region 11b and the third film region 11c in the second direction D2. The second direction D2 intersects with the first direction D1. In this example, the second direction D2 is the X-axis direction.

[0016] The first layer 31 is surrounded by the base layer 10B, the first film region 11a, the second film region 11b, and the third film region 11c. The first layer 31 is covered by the base layer 10B and the first film 11. This prevents the first layer 31 from being altered by external influences.

[0017] A detection target (e.g., hydrogen) exists outside the structure 18. The detection target (e.g., hydrogen) can pass through the first film 11 and reach the first layer 31. In the first layer 31, at least one of a change in volume and a change in electrical resistance occurs depending on the detection target.

[0018] A substance other than the detection target (for example, oxygen) is present outside the structure 18. When the substance other than the detection target (for example, oxygen) reaches the first layer 31, the first layer 31 may be altered. For example, when oxygen is taken into the first layer 31, the ability of the first layer 31 to take up the detection target changes. For example, when oxygen is taken into the first layer 31, the volume change corresponding to the detection target or the resistance change corresponding to the detection target is no longer the intended state.

[0019] In this embodiment, the first layer 31 is provided between the base layer 10B and the first film 11. The first film 11 prevents substances other than the detection target (e.g., oxygen) from reaching the first layer 31. This prevents adverse effects of substances other than the detection target (e.g., oxygen). Stable detection is possible.

[0020] In the embodiment, for example, the first layer 31 contains Pd, Cu, and Si. The first layer 31 may be a PdCuSi alloy. For example, the target substance to be detected includes hydrogen. When the first layer 31 contains PdCuSi, the target substance to be detected (hydrogen) is effectively captured in the first layer 31. At least one of a volume change and a resistance change occurs effectively.

[0021] The first layer 31 may further include at least one selected from the group consisting of Pt and Ti. These materials may function as a catalyst, for example, so that at least one of a volume change and a resistance change occurs more efficiently.

[0022] At least a portion of the first layer 31 is preferably amorphous. The amorphous first layer 31 more effectively captures the detection target (e.g., hydrogen). For example, high sensitivity is easily obtained. For example, the signal obtained from the structure 18 responds quickly to hydrogen. Hysteresis can be suppressed in the absorption and release of hydrogen.

[0023] For example, when oxygen reaches the first layer 31, Si contained in the first layer 31 may bond with the oxygen. This may cause Pd and Cu contained in the first layer 31 to bond and form crystals. The amorphous state of the first layer 31 may change to a crystalline state. This may change at least one of the characteristics of volume change and resistance change.

[0024] The base layer 10B includes at least one selected from the group consisting of silicon, aluminum, and titanium, and at least one selected from the group consisting of oxygen and nitrogen. In one example, the base layer 10B includes at least one selected from the group consisting of silicon nitride and silicon oxide. The base layer 10B may also include at least one selected from the group consisting of aluminum oxide and titanium nitride. This allows the base layer 10B to have stable characteristics.

[0025] 1(a), the first film region 11a is continuous with the second film region 11b and the third film region 11c. For example, the second film region 11b and the third film region 11c may contact the base layer 10B.

[0026] As shown in FIG. 1(a), the first film 11 may further include a second extension region 11ba and a third extension region 11ca. The second extension region 11ba is continuous with the second film region 11b. The second extension region 11ba extends along the base layer 10B. The third extension region 11ca is continuous with the third film region 11c. The third extension region 11ca extends along the base layer 10B.

[0027] 1(b), the first film 11 may include a fourth film region 11d and a fifth film region 11e. In the third direction D3, the first layer 31 is located between the fourth film region 11d and the fifth film region 11e. The third direction D3 intersects with a plane including the first direction D1 and the second direction D2. The third direction D3 may be, for example, the Y-axis direction.

[0028] For example, the first film region 11a is continuous with the fourth film region 11d and the fifth film region 11e. For example, the second film region 11b is continuous with the fourth film region 11d and the fifth film region 11e. For example, the third film region 11c is continuous with the fourth film region 11d and the fifth film region 11e. For example, the fourth film region 11d and the fifth film region 11e contact the base layer 10B.

[0029] 1(b), the first film 11 may further include a fourth extension region 11da and a fifth extension region 11ea. The fourth extension region 11da is continuous with the fourth film region 11d. The fourth extension region 11da extends along the base layer 10B. The fifth extension region 11ea is continuous with the fifth film region 11e. The fifth extension region 11ea extends along the base layer 10B.

[0030] The thickness t31 (see FIG. 1(a)) of the first layer 31 along the first direction D1 is, for example, not less than 10 nm and not more than 10 μm.

[0031] The thickness t11 (see FIG. 1(a)) of the first film region 11a along the first direction D1 is, for example, not less than 1 nm and not more than 1000 nm.

[0032] (Second embodiment) FIG. 2 is a schematic cross-sectional view illustrating the sensor according to the second embodiment. 2, the sensor 120 according to the embodiment includes a structure 18, a base 41, a fixed electrode 51, a support portion 10S, and a movable electrode 52. The structure 18 has the configuration described in relation to the first embodiment.

[0033] The fixed electrode 51 is fixed to the base 41. The support portion 10S is fixed to the base 41. The structure 18 is supported by the support portion 10S. The movable electrode 52 is supported by the structure 18. A gap g1 is provided between the fixed electrode 51 and the movable electrode 52, and between the base 41 and the structure 18. The structure 18 functions as the connecting portion 10C. The connecting portion 10C supports the movable portion 10M. The movable electrode 52 is included in the movable portion 10M.

[0034] For example, the volume of the structure 18 changes depending on the detection target. This causes the structure 18 to deform. This changes the distance d1 between the fixed electrode 51 and the movable electrode 52. The change in distance d1 changes the capacitance between the fixed electrode 51 and the movable electrode 52. The capacitance can change depending on the detection target. The detection target can be detected by detecting the capacitance.

[0035] 2, a circuit unit 70 may be provided. The circuit unit 70 may be included in the sensor 120. The circuit unit 70 may be provided separately from the sensor 120. The circuit unit 70 is capable of detecting a value corresponding to the capacitance. The circuit unit 70 outputs a signal corresponding to the capacitance.

[0036] 2, the structure 18 may further include a resistive element 18R. For example, at least a portion of the resistive element 18R may overlap the first layer 31 in the first direction D1. For example, a current is supplied from the circuit section 70 to the resistive element 18R. This increases the temperature of the resistive element 18R, and the temperature of the structure 18 increases. This changes the uptake and release characteristics of the detection target in the first layer 31. For example, higher sensitivity detection becomes possible.

[0037] Repeated rises and falls in temperature of the first layer 31 accelerates the deterioration of the first layer 31. By covering the first layer 31 with the first film 11, stable detection characteristics can be maintained even when the temperature rises and falls repeatedly.

[0038] (Third embodiment) FIG. 3 is a schematic cross-sectional view illustrating a sensor according to the third embodiment. 3, a sensor 130 according to this embodiment includes a structure 18, a base 41, and a support portion 10S. The structure 18 has the configuration described in relation to the first embodiment.

[0039] The support portion 10S is fixed to the base 41. The support portion 10S supports the structure 18. A gap g1 is provided between the base 41 and the structure 18.

[0040] In the sensor 130, the electrical resistance of the first layer 31 included in the structure 18 changes depending on the detection target. By detecting the electrical resistance, the detection target can be detected.

[0041] A circuit section 70 may be provided. The circuit section 70 is capable of detecting a value corresponding to the electrical resistance of the first layer 31. A signal corresponding to the electrical resistance of the first layer 31 is output from the circuit section 70.

[0042] 3, the structure 18 may further include a resistance member 18R. For example, at least a portion of the resistance member 18R may overlap the first layer 31 in the first direction D1.

[0043] For example, the temperature of the resistance member 18R rises, and the temperature of the structure 18 rises. As a result, the uptake and release characteristics of the detection target in the first layer 31 change. For example, higher sensitivity detection becomes possible. When the temperature of the first layer 31 repeatedly rises and falls, the deterioration of the first layer 31 accelerates. By covering the first layer 31 with the first film 11, stable detection characteristics can be maintained even when the temperature repeatedly rises and falls.

[0044] The embodiment may include the following configurations (e.g., technical solutions). (Configuration 1) A base layer; A first membrane; The first layer and a structure comprising: the first film contains at least one selected from the group consisting of silicon and aluminum, and oxygen; At least one of the volume of the first layer and the electrical resistance of the first layer is variable depending on a detection target around the structure; the first film includes a first film region, a second film region, and a third film region; the first layer is between the base layer and the first film region in a first direction from the base layer to the first film region; In a second direction intersecting the first direction, the first layer is between the second film region and the third film region. (Configuration 2) 2. The sensor of claim 1, wherein the first membrane region is continuous with the second membrane region and the third membrane region. (Configuration 3) The sensor of configuration 1 or 2, wherein the second membrane region and the third membrane region are in contact with the base layer. (Configuration 4) the first film further includes a second extension region and a third extension region; the second extension region is continuous with the second film region, the second extension region extends along the base layer; the third extension region is continuous with the third film region, The sensor according to any one of configurations 1 to 3, wherein the third extension region extends along the base layer. (Configuration 5) the first film includes a fourth film region and a fifth film region; A sensor described in any one of configurations 1 to 4, wherein in a third direction intersecting a plane including the first direction and the second direction, the first layer is located between the fourth film region and the fifth film region. (Configuration 6) The sensor of configuration 5, wherein the first membrane region is continuous with the fourth membrane region and the fifth membrane region. (Configuration 7) The sensor of configuration 5 or 6, wherein the fourth film region and the fifth film region are in contact with the base layer. (Configuration 8) the first film further includes a fourth extension region and a fifth extension region; the fourth extension region is continuous with the fourth film region, the fourth extension region extends along the base layer; the fifth extension region is continuous with the fifth membrane region, The sensor according to any one of configurations 5 to 7, wherein the fifth extension region extends along the base layer. (Configuration 9) 9. The sensor of any one of configurations 1 to 8, wherein the first layer includes Pd, Cu, and Si. (Configuration 10) 10. The sensor of claim 9, wherein the first layer further comprises at least one selected from the group consisting of Pt and Ti. (Configuration 11) 11. The sensor of embodiment 9 or 10, wherein at least a portion of the first layer is amorphous. (Configuration 12) 12. The sensor according to any one of configurations 9 to 11, wherein the detection target includes hydrogen. (Configuration 13) a substrate; a fixed electrode fixed to the substrate; a support fixed to the base; A movable electrode; Furthermore, the structure is supported by the support, the movable electrode is supported by the structure; 13. The sensor according to any one of configurations 1 to 12, wherein a gap is provided between the fixed electrode and the movable electrode, and between the substrate and the structure. (Configuration 14) The structure further includes a resistance member; 14. The sensor of claim 13, wherein at least a portion of the resistive element overlaps the first layer in the first direction. (Configuration 15) 15. The sensor of claim 13, wherein the capacitance between the fixed electrode and the movable electrode is variable depending on the object to be detected. (Configuration 16) 16. The sensor of claim 15, further comprising circuitry capable of detecting a value corresponding to the capacitance. (Configuration 17) a substrate; a support fixed to the base; Furthermore, the support portion supports the structure, 13. The sensor according to any one of configurations 1 to 12, wherein a gap is provided between the substrate and the structure. (Configuration 18) The structure further includes a resistance member; 18. The sensor of claim 17, wherein at least a portion of the resistive member overlaps the first layer in the first direction. (Configuration 19) 19. The sensor of claim 17 or 18, further comprising circuitry capable of detecting a value corresponding to the electrical resistance. According to the embodiment, a sensor capable of stable detection can be provided.

[0045] The embodiments of the present invention have been described above with reference to specific examples. However, the present invention is not limited to these specific examples. For example, the specific configurations of the elements included in the sensor, such as the structures, layers, films, and circuitry, are within the scope of the present invention as long as a person skilled in the art can implement the present invention in a similar manner and obtain similar effects by appropriately selecting them from known ranges.

[0046] Furthermore, any combination of two or more elements of each specific example within the scope of technical feasibility is also included within the scope of the present invention as long as it includes the gist of the present invention.

[0047] In addition, all sensors that can be implemented by a person skilled in the art by appropriately modifying the design based on the sensor described above as an embodiment of the present invention also fall within the scope of the present invention as long as they include the gist of the present invention.

[0048] In addition, within the scope of the concept of the present invention, a person skilled in the art may come up with various modifications and alterations, and it will be understood that these modifications and alterations also fall within the scope of the present invention.

[0049] Although several embodiments of the present invention have been described, these embodiments are presented as examples and are not intended to limit the scope of the invention. These novel embodiments can be embodied in various other forms, and various omissions, substitutions, and modifications can be made without departing from the spirit of the invention. These embodiments and their modifications are included within the scope and spirit of the invention, and are also included in the scope of the invention and its equivalents as defined in the claims. [Explanation of symbols]

[0050] 10B...base layer, 10C...connection portion, 10M...movable portion, 10S...support portion, 11...first film, 11a to 11e...first to fifth film regions, 11ba to 11ea...second to fifth extension regions, 18...structure, 18R...resistance member, 31...first layer, 41...base, 51...fixed electrode, 52...movable electrode, 70...circuit portion, 110, 120, 130...sensor, D1 to D3...first to third directions, d1...distance, g1...gap, t11, t31...thickness

Claims

1. A base layer; A first membrane; The first layer, a structure comprising: the first film contains at least one selected from the group consisting of silicon and aluminum, and oxygen; At least one of the volume of the first layer and the electrical resistance of the first layer is variable depending on a detection target around the structure; the first film includes a first film region, a second film region, and a third film region; the first layer is between the base layer and the first film region in a first direction from the base layer to the first film region; In a second direction intersecting the first direction, the first layer is located between the second film region and the third film region, the first film includes a fourth film region and a fifth film region; In a third direction intersecting a plane including the first direction and the second direction, the first layer is located between the fourth film region and the fifth film region; the second film region, the third film region, the fourth film region, and the fifth film region are in contact with the base layer; the first layer is in contact with the base layer and the first film; the base layer includes at least one selected from the group consisting of silicon and aluminum, and oxygen; the first layer includes Pd, Cu, and Si; the detection target contains hydrogen, The sensor, wherein the first film and the base layer prevent oxygen from reaching the first layer and prevent Si contained in the first layer from bonding with oxygen.

2. The sensor of claim 1 , wherein the first layer further comprises at least one selected from the group consisting of Pt and Ti.

3. The sensor of claim 1 , wherein at least a portion of the first layer is amorphous.

4. a substrate; a fixed electrode fixed to the substrate; a support fixed to the base; A movable electrode; Furthermore, the structure is supported by the support, the movable electrode is supported by the structure; 4. The sensor according to claim 1, wherein a gap is provided between the fixed electrode and the movable electrode, and between the substrate and the structure.

5. The structure further includes a resistance member; The sensor of claim 4 , wherein at least a portion of the resistive member overlaps the first layer in the first direction.

6. a substrate; a support fixed to the base; Furthermore, the support portion supports the structure, 4. The sensor according to claim 1, wherein a gap is provided between the substrate and the structure.

7. The structure further includes a resistance member; The sensor of claim 6 , wherein at least a portion of the resistive member overlaps the first layer in the first direction.

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