Electromagnetic wave detecting element and electromagnetic wave sensor provided with the same

Abstract

An electromagnetic wave detecting element has an electromagnetic wave detecting portion having an electromagnetic wave absorber and detecting an electromagnetic wave, and an arm portion having a wiring layer electrically connected to the electromagnetic wave detecting portion. A part of the arm portion is disposed apart from the electromagnetic wave detecting portion by a first gap, and the electromagnetic wave absorber has a first protruding portion and a second protruding portion adjacent in a first direction with a second gap therebetween.

Description

Technical Field

[0001] This disclosure relates to an electromagnetic wave detection element and an electromagnetic wave sensor incorporating the electromagnetic wave detection element. Background Technology

[0002] Japanese Patent Application Publication No. 2022-126582 discloses an electromagnetic wave sensor for detecting electromagnetic waves. The electromagnetic wave sensor includes: an electromagnetic wave detection unit that has an electromagnetic wave absorber and detects electromagnetic waves; and two arms electrically connected to the electromagnetic wave detection unit. The electromagnetic wave absorber improves the absorption efficiency of electromagnetic waves absorbed by the electromagnetic wave detection unit. The electromagnetic wave absorber has a relatively simple shape, such as a rectangle, when viewed from the film thickness direction. Summary of the Invention

[0003] The larger the incident area of ​​the electromagnetic wave on the object being measured, the higher the electromagnetic wave absorption performance of the electromagnetic wave absorber. However, when the incident area is large, the volume of the electromagnetic wave absorber usually also increases, thus reducing the tracking performance of the temperature change of the electromagnetic wave detection unit relative to the change in electromagnetic wave intensity.

[0004] The purpose of this disclosure is to provide an electromagnetic wave detection element that has high temperature change tracking capability for changes in electromagnetic wave intensity.

[0005] The electromagnetic wave detection element disclosed herein includes: an electromagnetic wave detection section having an electromagnetic wave absorber and detecting electromagnetic waves; and an arm having a wiring layer electrically connected to the electromagnetic wave detection section. A portion of the arm is disposed with respect to the electromagnetic wave detection section separated by a first gap, and the electromagnetic wave absorber has a first protrusion and a second protrusion adjacent in a first direction and separated by a second gap.

[0006] The above and other objectives, features and advantages of this application will become clear from the following detailed description of the application with reference to the accompanying drawings. Attached Figure Description

[0007] Figure 1 This is a general side view of the electromagnetic wave sensor according to the first embodiment of this disclosure.

[0008] Figure 2 yes Figure 1 The image shows a partial top view of the electromagnetic wave sensor.

[0009] Figures 3A-3C yes Figure 2 The image shows a partial enlarged view and a partial cross-sectional view of the electromagnetic wave detection element.

[0010] Figure 4 This is an enlarged view of part A in Figure 3.

[0011] Figure 5A as well as Figure 5B This is a general top view of the electromagnetic wave detection element in Comparative Examples 1 and 2.

[0012] Figures 6A to 6C These are a general top view and a general cross-sectional view of the electromagnetic wave detection element of the first variation of the first embodiment.

[0013] Figures 7A to 7C These are a general top view and a general cross-sectional view of the electromagnetic wave detection element of the second variation of the first embodiment.

[0014] Figures 8A to 8D This is a partial top view of the electromagnetic wave detection element of the third variation of the first embodiment.

[0015] Figure 9 This is a general cross-sectional view of the electromagnetic wave detection element in the fourth variation of the first embodiment.

[0016] Figure 10 This is a general cross-sectional view of the electromagnetic wave detection element in the fifth variation of the first embodiment.

[0017] Figure 11 This is a general side view of the electromagnetic wave sensor according to the second embodiment of this disclosure.

[0018] Figure 12 This is a general side view of the electromagnetic wave sensor involved in a variation of the second embodiment.

[0019] Symbol Explanation

[0020] 11: Electromagnetic wave detection element

[0021] 21: Electromagnetic Wave Detection Department

[0022] 22: Temperature sensing element

[0023] 23: Electromagnetic wave absorber

[0024] 25: Protrusion

[0025] 26: Metal film

[0026] 31X, 31Y: Arm

[0027] 32: Wiring layer

[0028] 100: Electromagnetic wave sensor

[0029] 251: First protrusion

[0030] 252: Second protrusion Detailed Implementation

[0031] Hereinafter, embodiments of the electromagnetic wave detection element and the electromagnetic wave sensor equipped with the electromagnetic wave detection element of this disclosure will be described with reference to the accompanying drawings. The electromagnetic wave detection element of this disclosure detects electromagnetic waves. The accompanying drawings are schematic diagrams illustrating this disclosure, and there may be inconsistencies in the shapes or dimensions of elements between the drawings. In the following description and the accompanying drawings, the X direction (also referred to as the first direction) and the Y direction are directions parallel to the main surface 1A of the first substrate 1 and the main surface 2A of the second substrate 2. The main surfaces 1A and 2A are the surfaces of the first substrate 1 and the second substrate 2 that face each other. The X direction is perpendicular to the Y direction. The Z direction is a direction perpendicular to both the X and Y directions, and is either a direction perpendicular to the main surface 1A of the first substrate 1 and the main surface 2A of the second substrate 2, or the film thickness direction of the electromagnetic wave detection section 21.

[0032] In the following embodiments, an infrared sensor in which electromagnetic wave detection elements 11 are arranged in a two-dimensional array is described as the object. The infrared sensor primarily detects infrared light with a long wavelength of approximately 8–14 μm. Such an infrared sensor is mainly used as an imaging element in an infrared camera. Infrared cameras can be used not only as night vision scopes and night vision goggles, but also for measuring the temperature of people or objects. Furthermore, an infrared sensor in which multiple electromagnetic wave detection elements 11 are arranged in a one-dimensional array can be used as a sensor for measuring various temperatures or temperature distributions. Although the description is omitted, an infrared sensor in which multiple electromagnetic wave detection elements 11 are arranged in a one-dimensional array is also included within the scope of this disclosure. The detected electromagnetic waves are not limited to infrared light; for example, terahertz waves with wavelengths of 100 μm to 1 mm may also be detected.

[0033] First Implementation Method

[0034] Overall structure

[0035] Figure 1 This is a rough side view of the electromagnetic wave sensor 100. Figure 1 The first arm 31X and the second arm 31Y are omitted from the illustration. Five electromagnetic wave detection elements 11 are arranged in the X direction, but as will be described later, the number of electromagnetic wave detection elements 11 is not limited. The electromagnetic wave sensor 100 has a first substrate 1 and a second substrate 2 arranged opposite to each other, and a sidewall 3 connecting the first substrate 1 and the second substrate 2 and wound in the circumferential direction. The first substrate 1, the second substrate 2, and the sidewall 3 form a sealed internal space 4. Multiple electromagnetic wave detection elements 11, which function as sensing parts of the electromagnetic wave sensor 100, are provided in the internal space 4. The internal space 4 is under negative pressure or a vacuum, thus preventing or suppressing the convection of gas in the internal space 4 and reducing the thermal effects on the electromagnetic wave detection elements 11.

[0036] The first substrate 1 is mainly composed of a silicon substrate and has multiple electromagnetic wave detection elements 11. The first substrate 1 includes circuitry such as a Readout IC (ROIC) for reading the output signals of the electromagnetic wave detection elements 11, and internal wiring (not shown). Multiple solder pads (not shown) for input / output with the outside are formed on the outer side of the sidewall 3 of the first substrate 1. The solder pads are electrically connected to the circuitry via internal wiring. The second substrate 2 is also mainly composed of a silicon substrate and constitutes the input section for electromagnetic waves IR. The second substrate 2 is the substrate located on the side where the electromagnetic wave IR is incident on the object being detected. The second substrate 2 allows the electromagnetic wave IR to pass through, allowing the electromagnetic wave IR to be incident on the electromagnetic wave detection element 11. The first substrate 1 and the second substrate 2 can be germanium substrates that allow electromagnetic waves to pass through.

[0037] Figure 2 This is a partial top view of the electromagnetic wave sensor 100 viewed along the Z direction, and also schematically shows the first wiring 41X and the second wiring 41Y. Figure 3A This is a general top view of an electromagnetic wave detection element 11. Figure 3B It is along Figure 3A Approximate cross-sectional view of line 3B-3B. Figure 3C It is along Figure 3A A rough cross-sectional view of the 3C-3C line. Figure 2 , Figure 3A For ease of explanation, a temperature sensing element 22 is illustrated. Multiple electromagnetic wave sensing elements 11 are configured in an array, more specifically, as a two-dimensional lattice array consisting of multiple rows R extending along the X direction and multiple columns C extending along the Y direction. The temperature sensing element 22 (described later) of each electromagnetic wave sensing element 11 constitutes a unit or pixel in this array. Examples of the number of rows and columns in the array include 640 rows × 480 columns, 1024 rows × 768 columns, etc., but are not limited thereto. The first substrate 1 has multiple first wirings 41X extending in the X direction and multiple second wirings 41Y extending in the Y direction. The multiple first wirings 41X and multiple second wirings 41Y are disposed inside the first substrate 1, electrically connected to the ROIC, and extend at different positions in the Z direction.

[0038] Structure of electromagnetic wave detection element 11

[0039] like Figure 2 as well as Figures 3A-3CAs shown, each electromagnetic wave detection element 11 has an electromagnetic wave detection section 21, and a first arm 31X and a second arm 31Y connected to and supporting the electromagnetic wave detection section 21 at one end. Each of the first arm 31X and the second arm 31Y has a wiring layer 32 electrically connected to the temperature detection element 22 of the electromagnetic wave detection section 21, and two dielectric layers 33 sandwiching the wiring layer 32 in the Z direction. The wiring layer 32 can be formed, for example, of a metal such as titanium or a conductive nitride such as titanium nitride. The two dielectric layers 33 can be formed, for example, of the same material as the electromagnetic wave absorber 23 (described later) of the electromagnetic wave detection section 21. The wiring layer 32 of the first arm 31X is electrically connected to the first conductive pillar 34X, and the wiring layer 32 of the second arm 31Y is electrically connected to the second conductive pillar 34Y. A portion of the first arm 31X and a portion of the second arm 31Y are disposed with a first gap G1 between them and the electromagnetic wave detection section 21. Figure 2 as well as Figures 3A-3C In the example shown, the first gap G1 is either the gap between a portion of the adjacent first arm 31X in the X direction and the electromagnetic wave detection unit 21, or the gap between a portion of the adjacent second arm 31Y in the X direction and the electromagnetic wave detection unit 21. The length of the first gap G1 in the X direction is not fixed and can vary depending on its position. Furthermore, the length of the first gap G1 in the X direction between the first arm 31X and the electromagnetic wave detection unit 21 can be the same as, but different from, the length of the first gap G1 in the X direction between the second arm 31Y and the electromagnetic wave detection unit 21.

[0040] Each electromagnetic wave detection element 11 has a cylindrical first conductive pillar 34X and a second conductive pillar 34Y. The first conductive pillar 34X is electrically connected to a corresponding first wiring 41X, and the second conductive pillar 34Y is electrically connected to a corresponding second wiring 41Y. The first conductive pillar 34X supports the first arm 31X, and the electromagnetic wave detection unit 21 is supported via the first arm 31X. The second conductive pillar 34Y supports the second arm 31Y, and the electromagnetic wave detection unit 21 is supported via the second arm 31Y. The first conductive pillar 34X is electrically connected to the wiring layer 32 of the first arm 31X, and the second conductive pillar 34Y is electrically connected to the wiring layer 32 of the second arm 31Y.

[0041] The electromagnetic wave detection unit 21 includes a temperature sensing element 22, an electromagnetic wave absorber 23, a first electrode layer 24X, and a second electrode layer 24Y. The electromagnetic wave detection unit 21 absorbs incident electromagnetic waves and converts them into heat for detection. The electromagnetic wave detection unit 21 is a calorimeter. The electromagnetic waves incident on the electromagnetic wave detection unit 21 are absorbed by the electromagnetic wave absorber 23 and converted into heat. The intensity change of the electromagnetic waves incident on the electromagnetic wave detection unit 21 is detected as a temperature change by the temperature sensing element 22. The temperature sensing element 22 is a thermistor film. The shape of the temperature sensing element 22, viewed from the Z-direction, is a rectangle with opposite corners cut off, but it can also be a square, a rectangle, or a rectangle with rounded ends, etc. The thermistor film of the temperature sensing element 22 may contain at least one of the following: vanadium oxide, amorphous silicon, polycrystalline silicon, oxides with a manganese-containing spinel-type crystal structure, titanium oxide, yttrium-barium-copper oxide, and nanomaterials such as graphene or carbon nanotubes. In the temperature sensing element 22, instead of a thermistor film, it can also be a diode film such as a silicon diode film, a thermocouple film, a thermopile film, or a thermoelectric film such as a lead zirconate titanate film.

[0042] The electromagnetic wave absorber 23 covers at least a portion (in this embodiment, the entirety) of the temperature sensing element 22. The electromagnetic wave absorber 23 is formed of a dielectric material such as aluminum nitride, silicon nitride, aluminum oxide, or silicon oxide, and absorbs electromagnetic waves from the object being measured. The shape of the electromagnetic wave absorber 23 will be described later.

[0043] like Figure 3C As shown, the first electrode layer 24X and the second electrode layer 24Y are electrically connected to the temperature sensing element 22. The first electrode layer 24X is electrically connected to the wiring layer 32 of the first arm 31X, and the second electrode layer 24Y is electrically connected to the wiring layer 32 of the second arm 31Y. The first electrode layer 24X and the second electrode layer 24Y supply current to the temperature sensing element 22 in the in-plane direction (XY plane). The first and second electrode layers 24X and 24Y can be formed, for example, from a metal such as titanium or a conductive nitride such as titanium nitride. Although not shown in the figure, other electrode layers can be provided on the opposite side of the temperature sensing element 22 from the first electrode layer 24X and the second electrode layer 24Y. In this case, current flows through the temperature sensing element 22 in the film thickness direction (Z direction).

[0044] like Figure 1As shown, the electromagnetic wave sensor 100 has a metal film 26 disposed corresponding to each electromagnetic wave detection element 11. The metal film 26 is located on the opposite side from the side where the electromagnetic wave of the object being measured is incident, relative to the electromagnetic wave detection unit 21. The metal film 26 is disposed at least in a position opposite to the electromagnetic wave detection unit 21. A portion of the electromagnetic wave incident from the second substrate 2 passes through the electromagnetic wave detection unit 21, is reflected by the metal film 26, and is then incident on the electromagnetic wave detection unit 21. This improves the electromagnetic wave absorption efficiency of the electromagnetic wave detection unit 21. The metal film 26 can be formed of a material with high reflectivity to electromagnetic waves; examples include single-layer films of tantalum, titanium, gold, nickel-chromium alloys, aluminum, and silver, or laminated films composed of these materials.

[0045] Structure of electromagnetic wave absorber 23

[0046] Figure 4 yes Figure 3A Enlarged view of part A. Mainly referenced. Figures 3A-3C as well as Figure 4 The shape of the electromagnetic wave absorber 23 will be further described. The electromagnetic wave absorber 23 has two protrusions adjacent in the X direction separated by a second gap G2. In the following description, the two protrusions will be referred to as the first protrusion 251 and the second protrusion 252, and when there is no distinction between multiple protrusions including the first protrusion 251 and the second protrusion 252, they will be referred to as protrusions 25. The electromagnetic wave absorber 23 may also have three or more protrusions 25 including the first protrusion 251 and the second protrusion 252. In this case, the three or more protrusions 25 are adjacent in the X direction separated by the second gap G2. In this case, the length of each second gap G2 in the X direction may be the same, or each second gap G2 may be different. Sometimes the second gap G2 provided between two protrusions 25 adjacent in the X direction other than between the first protrusion 251 and the second protrusion 252 (e.g., in Figure 4 In this context, the second gap G2 located between the first protrusion 251 and the protrusion 25 located to the left of the first protrusion 251, or the second gap G2 located between the second protrusion 252 and the protrusion 25 located to the right of the second protrusion 252, is referred to as other second gaps G2. For example... Figure 3A As shown, in this embodiment, eight protrusions 25 are provided. Four protrusions 25 are disposed on one side of the temperature sensing element 22 in the Y direction, and the remaining four protrusions 25 are disposed on the other side of the Y direction. The four protrusions 25 on one side are arranged adjacent to each other in the X direction, separated by a second gap G2 of equal length in the X direction. The four protrusions 25 on the other side are also arranged adjacent to each other in the X direction, separated by a second gap G2 of equal length in the X direction. In this embodiment, the protrusions 25 are only provided on the electromagnetic wave absorber 23.

[0047] When viewed from the Z direction, the first protrusion 251 and the second protrusion 252 have a rectangular shape with a central axis 25C in the Y direction. For example... Figure 4 As shown, when viewed from the Z direction, the first protrusion 251 has two sides 2511 and 2512 extending opposite to each other and parallel to each other in the Y direction, and the second protrusion 252 has two sides 2521 and 2522 extending opposite to each other and parallel to each other in the Y direction. When viewed from the Z direction, the side 2512 of the first protrusion 251 and the side 2521 of the second protrusion 252 are opposite to each other and parallel to each other. The first protrusion 251 and the second protrusion 252 have the same shape and size, but at least one of their shapes and sizes may be different.

[0048] The electromagnetic wave absorber 23 has a first protrusion 251 and a second protrusion 252 that are adjacent in the X direction and separated by a second gap G2. Therefore, the electromagnetic wave of the object being measured resonates between the first protrusion 251 and the second protrusion 252, and the electromagnetic wave of the object being measured tends to concentrate at the first protrusion 251 and the second protrusion 252. Thus, the electromagnetic wave absorption performance of the electromagnetic wave absorber 23 is improved. Figure 5A This is a general top view of the electromagnetic wave detection unit 211 in Comparative Example 1. Figure 5A For ease of explanation, the temperature sensing element 22 is shown in the diagram. The dashed line represents the outline of the electromagnetic wave detection unit 21 of this embodiment. The planar area of ​​the electromagnetic wave absorber 231 of Comparative Example 1 is the same as the planar area of ​​the electromagnetic wave absorber 23 of this embodiment. Therefore, the incident area of ​​the electromagnetic wave is the same in both the electromagnetic wave absorber 23 of this embodiment and the electromagnetic wave absorber 231 of Comparative Example 1. However, the electromagnetic wave absorber 231 of Comparative Example 1... Figure 5A The upper and lower edges are straight, and no protrusions 25 are provided. In this embodiment, the electromagnetic wave absorber 23 generates resonance with the electromagnetic wave of the object being measured, resulting in high electromagnetic wave absorption efficiency. Therefore, the electromagnetic wave absorption performance of the electromagnetic wave absorber 23 is improved. Consequently, the responsiveness of the electromagnetic wave absorber 23 to temperature changes when the intensity of the incident electromagnetic wave changes is increased, thereby improving the tracking ability of the temperature change of the electromagnetic wave detection element 11 relative to changes in electromagnetic wave intensity.

[0049] When the X-direction length S of the second gap G2 between the first protrusion 251 and the second protrusion 252 is less than or equal to the wavelength of the electromagnetic wave to be measured, electromagnetic wave resonance is likely to occur. Therefore, the X-direction length S of the second gap G2 between the first protrusion 251 and the second protrusion 252 can also be less than or equal to the wavelength of the electromagnetic wave to be measured. Furthermore, when the width W (X-direction dimension of the first protrusion 251 and the second protrusion 252) of the first protrusion 251 and the second protrusion 252 is less than or equal to the wavelength of the electromagnetic wave to be measured, electromagnetic wave resonance is likely to occur. Therefore, the width W of the first protrusion 251 and the second protrusion 252 can also be less than or equal to the wavelength of the electromagnetic wave to be measured. As described above, the electromagnetic wave detection element 11 of this embodiment detects infrared radiation, therefore the wavelength of the electromagnetic wave to be measured is approximately 8 to 14 μm. Therefore, in this embodiment, the X-direction length S of the second gap G2 between the first protrusion 251 and the second protrusion 252 can be set to 8 μm or less, and the width W of the first protrusion 251 and the second protrusion 252 can be set to 8 μm or less.

[0050] The length L (Y-direction dimension) of the first protrusion 251 and the second protrusion 252 in the protruding direction can also be longer than the length S (L > S) of the second gap G2 between the first protrusion 251 and the second protrusion 252 in the X-direction. That is, the second gap G2 can also be configured to be longer in the protruding direction (Y-direction) of the first protrusion 251 and the second protrusion 252. The length L of the first protrusion 251 in the protruding direction can also be longer than the width W (X-direction) of the first protrusion 251, and the length L of the second protrusion 252 in the protruding direction can also be longer than the width W (X-direction) of the second protrusion 252. That is, the first protrusion 251 and the second protrusion 252 are configured to be longer in the protruding direction (Y-direction).

[0051] In this embodiment, a plurality of protrusions 25 are provided on the periphery of the electromagnetic wave absorber 23. However, in order to compare with the case where holes are provided inside the electromagnetic wave absorber 23, Figures 3A-3C The electromagnetic wave detection unit 21 and shown in this embodiment are... Figure 5B The electromagnetic wave detection unit 212 of Comparative Example 2 was used as the subject of simulation using the finite element method. Figure 5BFor ease of explanation, the temperature sensing element 22 is illustrated. Comparative Example 2 has a plurality of rectangular holes 233 inside the electromagnetic wave absorber 232. In this embodiment, the number of second gaps G2 between the protrusions 25 is the same as the number of holes 233 in Comparative Example 2, the planar shape of the second gaps G2 is the same as the planar shape of the holes 233, and the area of ​​the second gaps G2 is also equal to the area of ​​the holes 233. That is, the area of ​​the electromagnetic wave absorber 232 in Comparative Example 2 is the same as the area of ​​the electromagnetic wave absorber 23 in this embodiment. Both this embodiment and Comparative Example 2 have a metal film 26. Figure 3B and Figure 3C Infrared light with an incident wavelength of 10 μm is shown in the direction indicated. The results are shown in Table 1. "Temperature rise" indicates the average temperature rise after infrared light is incident on the electromagnetic wave absorbers 23 and 232. A metal film 26 is provided at a position opposite to the electromagnetic wave detection unit 21 of this embodiment and the electromagnetic wave detection unit 212 of Comparative Example 2. Almost all the infrared light transmitted through the electromagnetic wave absorbers 23 and 232 is reflected by the metal film 26. Therefore, it can be considered that the infrared light transmitted through the metal film 26 and the infrared light absorbed by the metal film 26 are zero. Therefore, it can be considered that the infrared light incident on the electromagnetic wave detection unit 21, except for the infrared light reflected by the entire system of the electromagnetic wave detection unit 21 and the metal film 26, is absorbed by the electromagnetic wave detection unit 21. Similarly, it can be considered that the infrared light incident on the electromagnetic wave detection unit 212, except for the infrared light reflected by the entire system of the electromagnetic wave detection unit 212 and the metal film 26, is absorbed by the electromagnetic wave detection unit 212. "Infrared reflectivity" is the ratio of infrared rays incident on the electromagnetic wave detection unit 21 that are reflected by the entire system of the electromagnetic wave detection unit 21 and the metal film 26; or the ratio of infrared rays incident on the electromagnetic wave detection unit 212 that are reflected by the entire system of the electromagnetic wave detection unit 212 and the metal film 26. "Infrared absorptivity" is the ratio of infrared rays incident on the electromagnetic wave detection unit 21 that are not reflected by the entire system of the electromagnetic wave detection unit 21 and the metal film 26; or the ratio of infrared rays incident on the electromagnetic wave detection unit 212 that are not reflected by the entire system of the electromagnetic wave detection unit 212 and the metal film 26. Compared to Comparative Example 2, this embodiment has a higher infrared absorptivity and superior infrared absorption efficiency. As a result, a larger temperature rise is considered to have occurred compared to Comparative Example 2. According to the results, the electromagnetic wave absorption performance of the electromagnetic wave absorber 23 is improved by having a first protrusion 251 and a second protrusion 252 that are adjacent in the X direction and separated by a second gap G2. This is believed to be because the electromagnetic wave of the object being measured resonates between the first protrusion 251 and the second protrusion 252, and the electromagnetic wave of the object being measured tends to concentrate at the first protrusion 251 and the second protrusion 252.

[0052] Table 1

[0053]

[0054] Hereinafter, modifications and other embodiments will be described, focusing on the differences from the first embodiment. Structures or effects that are omitted from the description are the same as those in the first embodiment.

[0055] First variation

[0056] Figure 6A This is a general top view of the electromagnetic wave detection element 11 involved in the first modified example. Figure 6B It is along Figure 6A Approximate cross-sectional view of line 6B-6B. Figure 6C It is along Figure 6A A rough cross-sectional view of line 6C-6C. Figure 6A For ease of explanation, a temperature sensing element 22 is illustrated. In this modified example, the temperature sensing element 22 is provided over approximately the entire area of ​​the electromagnetic wave detection section 21, and protrusions 25 are provided between the temperature sensing element 22 and the electromagnetic wave absorber 23. At the protrusions 251 and 252 on both sides of the X-direction, the electromagnetic wave absorber 23 is divided into two parts 231 and 232 by the temperature sensing element 22. However, regardless of whether the electromagnetic wave absorber 23 is divided by the temperature sensing element 22, and regardless of whether a temperature sensing element 22 is provided between the divided electromagnetic wave absorbers 23, electromagnetic wave resonance occurs between the first protrusion 251 and the second protrusion 252 of the electromagnetic wave detection section 21. Therefore, the electromagnetic wave sensing element 11 of this modified example can also improve the tracking performance of temperature changes relative to changes in electromagnetic wave intensity.

[0057] Second variation

[0058] Figure 7A This is a general top view of the electromagnetic wave detection element 11 involved in the second variation. Figure 7B It is along Figure 7A Approximate cross-sectional view of line 7B-7B. Figure 7C It is along Figure 7A A general cross-sectional view of the 7C-7C line. In this modified example, the temperature sensing element 22 is formed of a material with electromagnetic wave absorption properties, such as amorphous silicon, and the electromagnetic wave absorber 23 also serves as the temperature sensing element 22 (i.e., the temperature sensing element 22 also serves as the electromagnetic wave absorber 23). Figures 7A-7CIn the example shown, the wiring layer 32 of the first arm 31X and the wiring layer 32 of the second arm 31Y are also formed of the same material as the temperature sensing element 22. The temperature sensing element 22, which also serves as an electromagnetic wave absorber 23, is integrated with the wiring layers 32 of the first arm 31X and the second arm 31Y. In this modified example, a protrusion 25 is provided on the electromagnetic wave absorber 23, which also serves as a temperature sensing element 22. As described above, electromagnetic wave resonance is generated between the first protrusion 251 and the second protrusion 252 of the electromagnetic wave detection section 21. Therefore, the electromagnetic wave detection element 11 of this modified example can also improve the tracking performance of temperature changes relative to changes in electromagnetic wave intensity.

[0059] Third variation

[0060] Figures 8A to 8D This is a partial top view of the electromagnetic wave detection element in the third modified example. The planar shape of the protrusion 25 can be various shapes other than rectangular. Figure 8A as well as Figure 8B In the example shown, the protrusion 25 is a trapezoidal shape in which the width W2 (X-direction dimension) of the root 253 is wider than the width W3 (X-direction dimension) of the front end 254. Figure 8A In the example shown, adjacent protrusions 25 are separated from each other at their root 253, whereas, in Figure 8B In the example shown, adjacent protrusions 25 contact each other at their root 253. Figure 8C In the example shown, the width W2 of the root 253 of the protrusion 25 increases as it moves away from the front end 254, forming a rectangular shape between the root 253 and the front end 254. Figure 8D In the example shown, the protrusion 25 is triangular in shape.

[0061] Fourth variation

[0062] Figure 9 This is a rough cross-sectional view of the electromagnetic wave detection element in the fourth variation, equivalent to along... Figure 6A The cross-section of line 6B-6B. The protrusion 25 is only provided in a portion of the electromagnetic wave detection section 21 in the thickness direction (Z direction). That is, the protrusion 25 is only provided on the electromagnetic wave incident side of the electromagnetic wave absorber 23, and not on the opposite side of the temperature detection element 22 and the electromagnetic wave absorber 23 with respect to the temperature detection element 22. In other words, in this modified example, relative to... Figures 6A to 6CIn the first modified example shown, the protrusion 25 is provided only in a portion of the electromagnetic wave absorber 23 along its thickness direction (Z direction). Resonance of electromagnetic waves is generated between the two protrusions 25 regardless of their position in the thickness direction, thus improving the tracking accuracy of the electromagnetic wave detection element 11 in this modified example to reflect changes in electromagnetic wave intensity with temperature variations. For example, the protrusion 25 may also be provided only on the portion opposite to the electromagnetic wave incident side of the electromagnetic wave absorber 23. In this case, the electromagnetic waves transmitted through the electromagnetic wave absorber 23 and the electromagnetic waves reflected by the metal film 26 resonate between the two protrusions 25, thereby increasing electromagnetic wave absorption. Alternatively, the protrusion 25 may be provided on both sides opposite to the electromagnetic wave incident side and the electromagnetic wave incident side of the electromagnetic wave absorber 23. Although figures are omitted, Figures 3A-3C The first embodiment shown Figures 7A to 7C In the second modified example shown, the protrusion 25 can also be provided only in a portion of the thickness direction (Z direction) of the electromagnetic wave absorber 23.

[0063] Fifth variation

[0064] Figure 10 This is a rough cross-sectional view of the electromagnetic wave detection element in the fifth variation, equivalent to along... Figure 3A The cross-section of line 3B-3B. The cross-sectional shape of the protrusion 25 varies in the Z direction. In the illustrated example, the protrusion 25 is wider on the electromagnetic wave incident side and narrower on the opposite side. The protrusion 25 may also be narrower on the electromagnetic wave incident side and wider on the opposite side.

[0065] Second Implementation Method

[0066] Figure 11 This is a general side view of the electromagnetic wave sensor 100 according to the second embodiment. The electromagnetic wave sensor 100 has a plurality of first electrical connection members 42X and a plurality of second electrical connection members 42Y (in... Figure 11In the illustration, only one of the plurality of second electrical connection members 42Y is shown (and only a portion of the second electrical connection member 42Y in the Z direction is shown). The first electrical connection member 42X and the second electrical connection member 42Y are cylindrical conductors extending along the Z direction between the first substrate 1 and the second substrate 2 and electrically connected to the ROIC. A plurality of first wirings 41X and a plurality of second wirings 41Y are disposed on the second substrate 2, and the electromagnetic wave detection element 11 is supported on the second substrate 2. Each of the plurality of first wirings 41X is connected to a corresponding first electrical connection member 42X, and each of the plurality of second wirings 41Y is connected to a corresponding second electrical connection member 42Y. The structure of the electromagnetic wave detection unit 21, the first and second arm portions 31X, 31Y, the first and second conductive pillars 34X, 34Y, and the first and second wirings 41X, 41Y is the same as in the first embodiment. In this modified example, the electromagnetic wave detection unit 21 is supported on the second substrate 2, thus ensuring that the heat transfer path from local heat sources such as the ROIC provided on the first substrate 1 is longer than in the first embodiment, and suppressing the influence of heat from local heat sources on the temperature detection element 22. This embodiment can be combined with the modified examples 1 to 5 described above.

[0067] Variations of the second embodiment

[0068] Figure 12 This is a general side view of the electromagnetic wave sensor 100 according to a variation of the second embodiment. Here, the description focuses on the differences from the second embodiment. Structures or effects that are omitted from the description are the same as those in the second embodiment. In this variation, instead of the plurality of first wirings 41X in the second embodiment, a plurality of second wirings 44 extending in the X direction are provided. The positions of the plurality of electromagnetic wave detection elements 11 in the Z direction are between the positions of the plurality of second wirings 41Y in the Z direction and the positions of the plurality of second wirings 44 in the Z direction. Each of the plurality of second wirings 44 is electrically connected to a corresponding first electrical connection member 42X via a third electrical connection member 43. The second wirings 44 have the same function as the first wirings 41X, but further serve as the metal film 26 of the first embodiment. A first intermediate layer 45X including an insulating layer is provided between the first conductive pillar 34X and the second substrate 2, and a second intermediate layer 45Y including an insulating layer is provided between the second conductive pillar 34Y and the second wirings 44. This modified example includes a second wiring 44 that also serves as the metal film 26, thus, similar to the first embodiment, the electromagnetic wave absorption performance of the electromagnetic wave absorber 23 is improved.

[0069] While several preferred embodiments of this disclosure have been shown and described in detail, it should be understood that various changes and modifications may be made without departing from the spirit or scope of the appended claims.

Claims

1. An electromagnetic wave detection element, wherein, It has: an electromagnetic wave detection unit, which has an electromagnetic wave absorber and detects electromagnetic waves; as well as The arm portion has a wiring layer electrically connected to the electromagnetic wave detection unit. A portion of the arm is disposed with a first gap between it and the electromagnetic wave detection unit. The electromagnetic wave absorber has a first protrusion and a second protrusion that are adjacent in a first direction and separated by a second gap.

2. The electromagnetic wave detection element according to claim 1, wherein, The length of the second gap between the first protrusion and the second protrusion in the first direction is less than or equal to the wavelength of the electromagnetic wave of the object being measured.

3. The electromagnetic wave detection element according to claim 1, wherein, The length of the second gap between the first protrusion and the second protrusion in the first direction is less than 8 μm.

4. The electromagnetic wave detection element according to claim 1, wherein, The width of the first protrusion in the first direction is less than or equal to the wavelength of the electromagnetic wave of the object being measured.

5. The electromagnetic wave detection element according to claim 1, wherein, The width of the first protrusion in the first direction is less than 8 μm.

6. The electromagnetic wave detection element according to claim 1, wherein, The length of the first protrusion in the protrusion direction is longer than the length of the second gap between the first protrusion and the second protrusion in the first direction.

7. The electromagnetic wave detection element according to claim 1, wherein, The length of the first protrusion in the protrusion direction is longer than the width of the first protrusion in the first direction.

8. The electromagnetic wave detection element according to claim 1, wherein, The electromagnetic wave absorber has three or more protrusions, including the first protrusion and the second protrusion, and other second gaps are provided between two adjacent protrusions in the first direction, other than between the first protrusion and the second protrusion.

9. The electromagnetic wave detection element according to claim 1, wherein, It has a metal film located on the opposite side from the side where the electromagnetic wave of the object being measured is incident, relative to the electromagnetic wave detection unit.

10. An electromagnetic wave sensor, wherein, The device has a plurality of electromagnetic wave detection elements as described in any one of claims 1 to 9, wherein the plurality of electromagnetic wave detection elements are arranged in an array.

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