JP2007192696A - Thermal displacement element and radiation detection system using the same - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To reduce a change in the inclination of a member, when the member fixed to a displacement section is displaced. <P>SOLUTION: A supported section 2, supported by a substrate 1, includes individual displacement sections 4-1, 4-2 of a first displacement section 4, a thermal isolation section 5, and individual displacement sections 6-1, 6-2 of a second displacement section 6, which are successively connected from the substrate 1 to a movable electrode section 7. The individual displacement sections 4-1, 6-2 curve in a direction opposite to the substrate 1 and have a double-layer structure, consisting of a lower SiN film and an upper Al film. The individual displacement sections 4-2, 6-1 curve toward the substrate 1 and have a double-layer structure, consisting of a lower Al film and an upper SiN film. Even if the amount of incident infrared rays changes, the movable electrode section 7 is kept in parallel with the substrate 1, as it is at all times. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a thermal displacement element used in a thermal radiation detector such as a thermal infrared detector, and a radiation detector using the thermal displacement element.

  2. Description of the Related Art Conventionally, for example, in a capacitive thermal infrared detector or a light readout thermal infrared detector, a thermal displacement element including a base and a supported portion supported by the base has been used. (Patent Document 1 below). The supported portion includes an infrared absorbing portion that receives infrared rays and converts the infrared rays into heat, and a displacement portion that is thermally coupled to the infrared absorbing portion and is displaced with respect to the base according to the bimetal principle according to the heat. is doing. Therefore, the radiation is converted into heat, and the displacement portion is bent and displaced according to the heat. And the displacement read-out member used in order to obtain the predetermined change according to the displacement which arose in the displacement part is being fixed to the displacement part.

  Some optical readout type thermal infrared detectors detect the displacement of the displacement portion not as the inclination of the displacement readout member but as the height of the displacement readout member. In such an apparatus, for example, as the displacement readout member, a half mirror part that reflects only a part of the received readout light is fixed to the displacement part, and the reflective part is opposed to the half mirror part. It fixes to (FIG. 25 and FIG. 26 of patent document 1). In this case, when the readout light is irradiated from the half mirror part side, the reflected light from the reflection part and the reflected light from the half mirror part interfere and return to interference light, and the intensity of this interference light is the same as that of the half mirror part. Since it depends on the distance from the reflecting portion, interference light having an intensity corresponding to the amount of incident infrared rays can be obtained.

In the case of a capacitive thermal infrared detector, a movable electrode portion is fixed to the displacement portion of the thermal displacement element, and the fixed electrode portion is fixed to the base so as to face the movable electrode portion. Then, the change in the height of the movable electrode portion (the interval between the movable electrode portion and the fixed electrode portion) due to the displacement generated in the displacement portion is read as the capacitance between both electrode portions, and the amount of incident infrared rays is detected. Therefore, the capacitance-type thermal infrared detection device also detects the displacement of the displacement portion as the height of the displacement reading member, not as the inclination of the displacement reading member.
JP 2003-75259 A

  However, in the infrared detecting device using the conventional thermal displacement element, the height of the displacement readout member is detected as the displacement of the displacement readout member, not the inclination of the displacement readout member, but the displacement readout member is changed according to the amount of incident infrared rays. The inclination is configured to change, and the height of the displacement reading member generated with the inclination of the displacement reading member has been detected. Therefore, the change in the height of the displacement reading member with respect to the change in the amount of incident infrared rays is relatively small, and the infrared detection sensitivity is not always sufficient. Further, since the displacement reading member is tilted, in some cases, the displacement reading member may collide with the base, and a situation may occur in which the dynamic range of infrared detection is limited.

  This invention is made | formed in view of such a situation, When the member fixed to the displacement part displaces according to the change of the incident radiation amount, it can reduce the change of the inclination of the said member. It is an object of the present invention to provide a thermal displacement element and a radiation detection device using the same.

  In order to solve the above problems, the thermal displacement element according to the first aspect of the present invention includes a base and a supported portion supported by the base. The supported portion includes a heat separating portion having high thermal resistance, a radiation absorbing portion that receives radiation and converts it into heat, and first and second displacement portions. Each of the first displacement portion and the second displacement portion has a plurality of individual displacement portions. Each of the plurality of individual displacement portions of the first displacement portion includes at least two layers of different materials having different expansion coefficients that overlap each other. Each of the plurality of individual displacement portions of the second displacement portion includes at least two layers of different materials having different expansion coefficients that overlap each other. The first displacement portion is mechanically continuous with the base body without passing through the heat separation portion. The radiation absorbing portion and the second displacement portion are mechanically continuous with the base via the heat separation portion and the first displacement portion. The second displacement part is thermally coupled to the radiation absorbing part. At least one individual displacement portion of the plurality of individual displacement portions of the first displacement portion is curved toward the base in a predetermined state where the amount of radiation received by the radiation absorption portion is small. At least one other individual displacement portion of the plurality of individual displacement portions of the first displacement portion is curved in the state opposite to the base. At least one individual displacement portion of the plurality of individual displacement portions of the second displacement portion is curved toward the base in the state. At least one other individual displacement portion of the plurality of individual displacement portions of the second displacement portion is curved in the state opposite to the base. The supported part may be formed of a thin film.

  The radiation may be not only infrared rays but also invisible light such as X-rays and ultraviolet rays and other various types of radiation. This is the same for each aspect described later.

  The thermal displacement element according to a second aspect of the present invention is the thermal displacement element according to the first aspect, wherein (i) the plurality of individual displacement portions of the first displacement portion are arranged from the start point of the first displacement portion. (Ii) the plurality of individual displacement portions of the second displacement portion from the start point portion of the second displacement portion to the end point portion of the first displacement portion; And sequentially connected in a predetermined direction to the end point of the second displacement part, and (iii) the direction from the start point of the first displacement part toward the end point of the first displacement part, The direction from the start point of the second displacement part toward the end point of the second displacement part is substantially opposite.

  In this specification, the starting point of the displacement portion (or individual displacement portion) is a route that is mechanically continuous from the substrate and is located on the side closer to the substrate among the end portions of the displacement portion (or individual displacement portion). Refers to the end. Further, the end point portion of the displacement portion (or individual displacement portion) refers to the end portion of the displacement portion (or individual displacement portion) that is far from the base body in the mechanically continuous route from the base body.

  The thermal displacement element according to a third aspect of the present invention is the thermal displacement element according to the first aspect, wherein (i) the plurality of individual displacement portions of the first displacement portion are arranged from the start point of the first displacement portion. (Ii) the plurality of individual displacement portions of the second displacement portion from the start point portion of the second displacement portion to the end point portion of the first displacement portion; And sequentially connected in a predetermined direction to the end point of the second displacement part, and (iii) the direction from the start point of the first displacement part toward the end point of the first displacement part, The direction from the start point of the second displacement part toward the end point of the second displacement part is substantially the same.

  A thermal displacement element according to a fourth aspect of the present invention is the thermal displacement element according to the second or third aspect, wherein (i) the number of the plurality of individual displacement portions of the first displacement portion and the number of the second displacement portions are the same. The number of each of the plurality of individual displacement portions is two, and (ii) the individual displacement portion on the start point side of the first displacement portion of the plurality of individual displacement portions of the first displacement portion, And the individual displacement portion on the end point side of the second displacement portion among the plurality of individual displacement portions of the second displacement portion is curved in the state opposite to the base, and (iii) Of the plurality of individual displacement portions of the first displacement portion, the individual displacement portion on the end point side of the first displacement portion, and the plurality of individual displacement portions of the second displacement portion. The individual displacement portion on the start point side of the second displacement portion is curved toward the base in the above state.

  The thermal displacement element according to the fifth aspect of the present invention is the thermal displacement element according to the fourth aspect, wherein the length from the start point to the end point of each individual displacement part of the first displacement part is substantially equal to each other. The length from the start point to the end point of each individual displacement part of the second displacement part is substantially equal to each other.

  A thermal displacement element according to a sixth aspect of the present invention is the thermal displacement element according to any one of the first to fifth aspects, wherein (i) the plurality of individual displacement portions of the first displacement portion are in the state in the state. The at least two layers of the individual displacement portion that curves to the side and the at least two layers of the individual displacement portion that curves to the side opposite to the base in the state are the same in the materials constituting each layer and each (Ii) with respect to the plurality of individual displacement portions of the second displacement portion, the at least two layers of the individual displacement portion curved toward the base in the state and the state In the at least two layers of the individual displacement portion that curves to the opposite side of the base, the materials constituting each layer are the same and the overlapping order of the layers of each material is reversed.

  A thermal displacement element according to a seventh aspect of the present invention includes a base and a supported portion supported by the base. The supported portion includes a radiation absorbing portion that receives radiation and converts it into heat, and a displacement portion that has a plurality of individual displacement portions and is thermally coupled to the radiation absorbing portion. Each of the plurality of individual displacement portions includes at least two layers of different materials having different expansion coefficients that overlap each other. The plurality of individual displacement portions are sequentially mechanically connected in a predetermined direction from the start point portion of the displacement portion to the end point portion of the displacement portion. At least one individual displacement portion of the plurality of individual displacement portions is curved toward the base body in a predetermined state in which the amount of radiation received by the radiation absorbing portion is small. At least one other individual displacement portion of the plurality of individual displacement portions is curved in the state opposite to the base.

  A radiation detection apparatus according to an eighth aspect of the present invention is the thermal displacement element according to any one of the first to sixth aspects, and a displacement readout member fixed to the second displacement part, And a displacement reading member used for obtaining a predetermined change corresponding to the displacement generated in the second displacement portion.

  In the radiation detection apparatus according to a ninth aspect of the present invention, in the eighth aspect, the displacement readout member is a half mirror that reflects only a part of the received readout light, and faces the half mirror. And a reflecting portion fixed to the base.

  The radiation detection apparatus according to a tenth aspect of the present invention is the radiation detection apparatus according to the eighth aspect, wherein the displacement reading member is a movable electrode portion, and is fixed to the base so as to face the movable electrode portion. It has a part.

  According to the present invention, when the member fixed to the displacement portion is displaced according to the change in the amount of incident radiation, the thermal displacement element capable of reducing the change in the inclination of the member, and the use thereof A radiation detection device can be provided.

  Hereinafter, a thermal displacement element and a radiation detection apparatus according to the present invention will be described with reference to the drawings.

In the following description, an example in which the radiation is infrared is described, but the radiation may be X-rays other than infrared, ultraviolet rays, and other various types of radiation.

  [First Embodiment]

  FIG. 1 is a schematic plan view schematically showing a unit pixel (unit element) of the radiation detection apparatus according to the first embodiment of the present invention. 2 is a schematic sectional view taken along line X1-X2 in FIG. 1, FIG. 3 is a schematic sectional view taken along line X3-X4 in FIG. 1, and FIG. 4 is taken along line Y1-Y2 in FIG. It is a schematic sectional drawing. However, FIGS. 1 to 4 show a state before the sacrificial layer 20 is removed during the manufacture of the radiation detection apparatus according to the present embodiment. The sacrificial layer 20 is shown in FIGS. 2 to 4, but omitted in FIG. Although not shown in the drawing, the schematic cross-sectional view along the line X5-X6 in FIG. 1 is the same as FIG. 3, and the schematic cross-sectional view along the line X7-X8 in FIG. .

  For convenience of explanation, as shown in FIG. 1, the X axis, the Y axis, and the Z axis that are orthogonal to each other are defined (the same applies to the drawings described later). The surface of the substrate 1 is parallel to the XY plane. The direction of the arrow in the Z-axis direction is called the + Z direction or + Z side, and the opposite direction is called the -Z direction or -Z side, and the same applies to the X-axis direction and the Y-axis direction. The + side in the Z-axis direction may be referred to as the upper side, and the − side in the Z-axis direction may be referred to as the lower side.

  FIGS. 5A and 5B are diagrams schematically showing the completed state of the radiation detection apparatus according to the present embodiment after removing the sacrificial layer 20 in a greatly simplified manner. It corresponds to a visual map. FIG. 5A shows that when a low-temperature object near normal temperature is being observed (that is, a state where infrared rays i from the low-temperature object are incident), the thermal equilibrium is reached when the environmental temperature is normal temperature T0. The state when the temperature of the substrate and each part of the element is also T0 is shown. FIG. 5B shows a state in which a high-temperature object having a considerably high temperature is observed when the environmental temperature and the substrate temperature are T0 (that is, an infrared ray i from the high-temperature object is incident). Yes. In addition, in order to make an understanding easy, in FIG. 5, the bending condition of the 1st and 2nd displacement parts 4 and 6 is exaggerated and shown. This also applies to FIGS. 10, 14 and 18 described later.

  The radiation detection apparatus according to this embodiment includes a silicon substrate 1 as a base, a supported portion 2 supported by the substrate 1, and a predetermined displacement corresponding to the displacement generated in the second displacement portion 6 of the supported portion 2. As a displacement reading member used for obtaining a change, a movable electrode portion 7 and a fixed electrode portion 8 made of an Al film or the like formed on the substrate 1 so as to face the movable electrode portion 7 are provided. .

  In the present embodiment, the supported portion 2 is supported in a state of being floated on the substrate 1 via two legs 3 rising from the substrate 1 in the Z-axis direction (vertical direction). The supported portion 2 includes two first displacement portions 4, two heat separation portions 5 having high thermal resistance, two second displacement portions 6, and an infrared absorption portion that receives infrared rays i and converts them into heat. 9.

  The radiation detection apparatus according to the present embodiment is configured to be bilaterally symmetric with respect to the left and right in FIG. 1, and in order to obtain the stability of the mechanical structure, the leg portion 3, the first displacement portion 4, and the heat separation portion. Two sets of 5 and the second displacement part 6 are provided. However, in the present invention, the number of the sets may be one or more.

  As shown in FIG. 1, the first displacement portion 4 is mechanically connected sequentially in the −X direction from the + X side end portion (start point portion) to the −X side end portion (end point portion). It consists of two individual displacement portions 4-1 and 4-2. The + X side end portion (starting point portion) of the + X side individual displacement portion 4-1 is connected to the leg portion 3. The −X side end portion (end point portion) of the individual displacement portion 4-1 is connected to the + X side end portion (start point portion) of the −X side individual displacement portion 4-2 by the connection portion 4a. An end portion (end point portion) on the −X side of the individual displacement portion 4-2 is connected to one end portion of the heat separation portion 5 by a connection portion 5a. Therefore, the first displacement part 4 is mechanically continuous with the substrate 1 without the heat separation part 5 interposed therebetween.

  In the present embodiment, as shown in FIG. 2, the individual displacement portion 4-1 is a lower layer that overlaps each other in the Z-axis direction (vertical direction) as two layers of different materials having different expansion coefficients. It is composed of a SiN film 21 on the side and an Al film 22 on the upper side. In the stage where the sacrificial layer 20 made of resist or the like is not removed, the individual displacement portion 4-1 is held by the sacrificial layer 20 and is not curved and is parallel to the substrate 1 as shown in FIGS. 1 and 2. Although extending straight in the X-axis direction, if the sacrificial layer 20 is finally removed by setting the film thickness of the films 21 and 22 and the film-forming conditions at the time of manufacture, the internal stress of the films 21 and 22 Therefore, as shown in FIG. 5A, it is curved upward (in the + Z direction, opposite to the substrate 1) at room temperature. Since the Al film 22 has a larger expansion coefficient than the SiN film 21, when the individual displacement portion 4-1 receives heat and the temperature rises, the degree of upward bending decreases according to the temperature.

  In addition, the number of layers and material which comprise the individual displacement part 4-1 are not limited to the example mentioned above. This also applies to individual displacement portions 4-2, 5-1 and 5-2 described later.

  In the present embodiment, the leg portion 3 is formed by continuously extending the SiN film 21 and the Al film 22 constituting the individual displacement portion 4-1 as they are. A diffusion layer 10 is formed below the legs 3 in the substrate 1. The Al film 22 is electrically connected to the diffusion layer 10 through the contact hole formed in the SiN film 21 at the leg 3. The movable electrode portion 7 is electrically connected to the diffusion layer 10 via an Al film 22 and Al layers 23, 25, and 26 and a Ti wiring layer 24 described later. On the other hand, on the substrate 1, a diffusion layer 11 is formed below the fixed electrode portion 8, and both are electrically connected. Although not shown in the drawing, a known readout circuit for reading out the capacitance between the diffusion layers 10 and 11 is formed on the substrate 1.

  The individual displacement portion 4-2 includes a lower Al film 23 and an upper SiN film 21 that overlap each other in the Z-axis direction (vertical direction) (this SiN film 21 extends continuously from the individual displacement portion 4-1. It is composed of. In the stage where the sacrificial layer 20 is not removed, the individual displacement part 4-2 is held by the sacrificial layer 20 and is not curved and parallel to the substrate 1 in the X-axis direction, as shown in FIGS. Although the film extends straight, when the sacrificial layer 20 is finally removed by setting the film thickness of the films 23 and 21 and the film forming conditions at the time of manufacture, the internal stress of the films 23 and 21 causes a normal temperature. As shown to Fig.5 (a), it curves below (-Z direction, the board | substrate 1 side). When the individual displacement portion 4-2 receives heat and the temperature rises, the degree of downward bending decreases according to the temperature.

  In the present embodiment, the length L1 from the start point to the end point of the individual displacement part 4-1 and the length L2 from the start point to the end point of the individual displacement part 4-2 are substantially equal. Yes. Thus, it is preferable that both are equal, but the present invention is not necessarily limited to this. The film 21 on the lower side of the individual displacement part 4-1 and the film 21 on the upper side of the individual displacement part 4-2 are substantially equal to each other, and the film 22 on the upper side of the individual displacement part 4-1. Although the film thicknesses of the films 23 below the individual displacement portions 4-2 are substantially the same, they are not necessarily limited to this.

  As shown in FIG. 2, the connecting portion 4 a is composed of a SiN film 21 and Al films 22 and 23 that continuously extend from the individual displacement portions 4-1 and 4-2 as they are. In the connection part 4a, the Al film 22 and the Al film 23 are electrically connected through a contact hole formed in the SiN film 21.

  The heat separation part 5 is made of a material having high heat insulation properties, and in this embodiment, the heat separation part 5 is made of a SiN film 21 that continuously extends from the individual displacement part 4-2. On the heat separation part 5, a Ti wiring layer 24 is formed so as to be narrow so as not to impair its heat insulation. The connection part 5a is composed of a SiN film 21 and an Al film 23 that continuously extend from the individual displacement part 4-2 and the heat separation part 5 as they are. In the connection portion 5a, the Al film 23 and the Ti wiring layer 24 are electrically connected through a contact hole formed in the SiN film 21. The heat separation part 5 is configured in a J-shape mainly extending in the X-axis direction and then extending in the Y-axis direction and then extending in the X-direction again.

  As shown in FIG. 1, the second displacement portion 6 is mechanically connected sequentially in the + X direction from the −X side end portion (start point portion) to the + X side end portion (end point portion). It consists of two individual displacement portions 6-1 and 6-2. The −X side end portion (starting point portion) of the −X side individual displacement portion 6-1 is connected to the other end portion of the heat separating portion 5 by the connecting portion 5b. The + X side end portion (end point portion) of the individual displacement portion 6-1 is connected to the −X side end portion (start point portion) of the + X side individual displacement portion 6-2 by the connecting portion 6a. The + X side end (end point) of the individual displacement part 6-2 is connected to the movable electrode part 7 by a connection part 7a. Therefore, the second displacement portion 6 is mechanically continuous with the substrate 1 via the heat separation portion 5 and the first displacement portion 4.

  As shown in FIG. 3, the individual displacement portion 6-1 includes a lower Al film 25 and an upper SiN film 21 that overlap each other in the Z-axis direction (vertical direction) (this SiN film 21 is separated from the heat separation portion 5. It is continuously extended as it is.) In the stage where the sacrificial layer 20 is not removed, the individual displacement part 6-1 is held by the sacrificial layer 20 and is not curved and parallel to the substrate 1 in the X-axis direction, as shown in FIGS. Although it extends straight, when the sacrificial layer 20 is finally removed by setting the film thickness of the films 25 and 21 and the film forming conditions at the time of manufacture, the internal stress of the films 25 and 21 causes the room temperature As shown to Fig.5 (a), it curves below (-Z direction, the board | substrate 1 side). When the individual displacement portion 6-1 receives heat and rises in temperature, the degree of downward bending decreases according to the temperature.

  In the present embodiment, the length L3 from the start point to the end point of the individual displacement part 6-1 and the length L4 from the start point to the end point of the individual displacement part 6-2 are substantially equal. Yes. Thus, it is preferable that both are equal, but the present invention is not necessarily limited to this. In addition, the film thicknesses of the upper film 21 of the individual displacement part 6-1 and the lower film 21 of the individual displacement part 6-2 are substantially the same, and the lower film 25 of the individual displacement part 6-1. The film thicknesses of the films 26 on the upper side of the individual displacement portions 6-2 are substantially the same, but are not necessarily limited thereto.

  As shown in FIG. 3, the connecting portion 6a is composed of a SiN film 21 and Al films 25 and 26 that continuously extend from the individual displacement portions 6-1 and 6-2 as they are. In the connection portion 6a, the Al film 25 and the Al film 26 are electrically connected through a contact hole formed in the SiN film 21.

  The connection part 5b is composed of a SiN film 21 and an Al film 25 that continuously extend from the heat separation part 5 and the individual displacement part 6-1. In the connection portion 5b, the Al film 25 and the Ti wiring layer 24 are electrically connected through a contact hole formed in the SiN film 21.

  As shown in FIG. 3, the individual displacement portion 6-2 includes a lower SiN film 21 that overlaps each other in the Z-axis direction (vertical direction) (this SiN film 21 is continuously formed from the individual displacement portion 6-1 as it is. And the upper Al film 26. In the stage where the sacrificial layer 20 is not removed, the individual displacement portion 6-2 is held by the sacrificial layer 20 and is not curved and parallel to the substrate 1 in the X-axis direction, as shown in FIGS. Although it extends straight, when the sacrificial layer 20 is finally removed by setting the film thickness of the films 26 and 21, the film forming conditions at the time of manufacture, and the like, the internal stress of the films 26 and 21 causes a normal temperature. As shown in FIG. 5A, it is curved upward (in the + Z direction, opposite to the substrate 1). When the individual displacement portion 6-2 receives heat and the temperature rises, the degree of upward bending decreases according to the temperature.

  The movable electrode portion 7 is composed of an Al film 26 continuously extending from the individual displacement portion 6-2 through the connection portion 7a. The infrared absorbing portion 9 is composed of an infrared absorbing film 27 such as gold black and is formed on the upper surface of the movable electrode portion 7. The infrared absorbing portion 9 is thermally coupled to the second displacement portion 6 via the movable electrode portion 7 and the connection portion 7a. Thereby, the infrared absorption unit 9 is mechanically continuous with the substrate 1 via the heat separation unit 5 and the first displacement unit 4. However, instead of forming the infrared absorbing portion 9 on the upper surface of the movable electrode portion 7, for example, a film constituting the second displacement portion 6 may be used as the infrared absorbing portion. An infrared absorbing film such as gold black may be formed as the infrared absorbing portion.

  As shown in FIG. 3, the connecting portion 7 a is composed of an Al film 26 and an infrared absorbing film 27 that continuously extend from the individual displacement portion 6-2, the movable electrode portion 7, and the infrared absorbing portion 9.

  As can be seen from the above description, the direction from the start point to the end point of the first displacement portion 4 is the direction of the −X direction, whereas from the start point to the end point of the second displacement portion 6. The direction of heading is the direction of the + X direction, and both are opposite.

  Although not shown in the drawings, components other than the individual displacement portions 4-1, 4-2, 6-1, 6-2 (for example, the movable electrode portion 7, the heat separation portion 5, etc.) It is preferable to have a configuration including a flat portion and a rising portion or a falling portion formed so as to rise or fall over at least a part of the peripheral portion of the flat portion. In this case, the plane portion is reinforced by the rising portion or the falling portion, and the film thickness can be reduced while ensuring a desired strength, which is preferable. This also applies to each embodiment described later.

  Although not shown in the drawings, in the radiation detection apparatus according to the present embodiment, the unit pixels shown in FIG. 1 and the like are arranged on the substrate 1 in a one-dimensional or two-dimensional manner. This also applies to each embodiment described later.

  As can be seen from the above description, in this embodiment, the thermal displacement of the substrate 1, the leg 3, the supported portion 2, the movable electrode portion 7, and the infrared absorbing portion 9 generates a displacement according to the heat generated by infrared rays. An element is configured, and one supported portion 2 of the thermal displacement element is used in each unit pixel.

  The radiation detection apparatus according to the present embodiment can be manufactured by using a semiconductor manufacturing technique such as film formation and patterning, etching, and sacrificial layer 20 formation / removal. Eventually, the sacrificial layer 20 is removed, and a state as shown in FIG.

  In the present embodiment, as shown in FIG. 5, infrared rays i from the object to be observed are incident from above. At this time, an infrared ray shielding part (not shown) provided in the package or the like causes the infrared ray i from the object to be observed to be incident on the first displacement part 4 (particularly, the SiN film 21 having infrared absorptivity is incident on the infrared i incident side). It is preferable to shield from light so as not to enter the individual displacement portion 4-2). However, such light shielding is not always necessary.

  According to the present embodiment, since the first and second displacement portions 4 and 6 are constituted by the individual displacement portions 4-1, 4-2, 6-1 and 6-2 as described above, In a state where a low-temperature object near T0 is being observed, when the ambient temperature is normal temperature T0, when the thermal equilibrium is reached and the temperature of the substrate and each part of the element also becomes T0, the state is as shown in FIG. . That is, the first displacement portion 4 has an S-shape as a whole, and the heat separation portion 5 is parallel to the substrate 1. Further, since the second displacement portion 6 also has an S shape as a whole, the movable electrode portion 7 is also parallel to the substrate 1.

  When the environmental temperature and the substrate temperature are T0 and a high-temperature object having a considerably high temperature is observed, the infrared ray i from the high-temperature object is converted into heat by the infrared absorption unit 9, and the second displacement unit 6 is converted by this heat. The degree of curvature of the individual displacement portions 6-1 and 6-2 is reduced. At this time, the degree of the upward bending of the individual displacement part 6-1 is the same as the degree of the downward bending of the individual displacement part 6-2. Further, since the heat converted by the infrared absorbing unit 9 is hardly conducted to the first displacement unit 4 by the heat separation unit 5 in a relatively short time, the individual displacement unit 4-1 of the second displacement unit 4. 4-2 hardly changes. Accordingly, the height (Z-direction position) of the movable electrode portion 7 is moved upward while being parallel to the substrate 1, and the interval between the movable electrode portion 7 and the fixed electrode portion 8 is widened. It depends on the amount of i. The change in the interval is read out by the readout circuit as a change in the capacitance between the electrode portions 7 and 8. Unit pixels are arranged one-dimensionally or two-dimensionally, and an infrared image signal can be obtained from the readout circuit.

  Considering the case where the environmental temperature changes from T0 by ΔT, if each element part reaches a thermal equilibrium state with respect to the change, not only the temperature of the first individual displacement part 4 changes by ΔT but also thermal separation. The temperature of the second individual displacement part 6 also changes by ΔT via the part 5. This is because when considering the change in the environmental temperature, it can be considered that there is sufficient time for ΔT to be conducted to the second individual displacement portion via the heat separation portion 5. When the temperature of the first displacement unit 4 changes by ΔT, the height of the heat separation unit 5 increases (or decreases) by that amount, but the temperature of the second displacement unit 6 also changes by ΔT, and accordingly. Therefore, the distance in the Z-axis direction between the heat separating portion 5 and the movable electrode portion 7 is shortened (or widened), so that both cancel each other and the height (Z-direction position) of the movable electrode portion 7 does not change. Therefore, according to the present embodiment, infrared detection can be performed without the influence of environmental temperature changes. Even when the environmental temperature changes by ΔT in this way, the thermal separation unit 5 and the movable electrode unit 7 remain parallel to the substrate 1.

  Thus, according to this Embodiment, the movable electrode part 7 can always be made parallel. Further, as can be seen from FIG. 5, in the present embodiment, the distance between the movable electrode portion 7 and the fixed electrode portion 8 is narrow when the temperature of the object to be observed is low near room temperature, and the temperature increases. It spreads as the amount of incident infrared rays increases. Advantages obtained by these will be described with reference to a comparative example.

  FIG. 6 is a schematic plan view schematically showing a unit pixel (unit element) of the radiation detection apparatus according to the comparative example. 7 is a schematic sectional view taken along line X9-X10 in FIG. 6, FIG. 8 is a schematic sectional view taken along line X11-X12 in FIG. 6, and FIG. 9 is taken along line Y9-Y10 in FIG. It is a schematic sectional drawing. However, FIGS. 6 to 9 show a state before the sacrificial layer 20 is removed during the manufacture of the radiation detection apparatus according to this comparative example. The sacrificial layer 20 is shown in FIGS. 7 to 9, but omitted in FIG. Although not shown in the drawing, the schematic cross-sectional view along the line X13-X14 in FIG. 6 is the same as FIG. 8, and the schematic cross-sectional view along the line X15-X16 in FIG. .

  FIGS. 10A and 10B are diagrams schematically showing the completed state of the radiation detection apparatus according to this comparative example after the sacrificial layer 20 is greatly simplified, as seen in the direction of arrow B in FIG. It corresponds to the figure. FIG. 10A shows a state in which a thermal equilibrium is reached and the temperature of each part of the substrate and the element reaches T0 when the ambient temperature is normal temperature T0 in a state where a low-temperature object near normal temperature is observed. ing. FIG. 10B shows a state in which a high-temperature object having a considerably high temperature is observed when the environmental temperature and the substrate temperature are T0.

  6 to 10, the same or corresponding elements as those in FIGS. 1 to 5 are denoted by the same reference numerals, and redundant description thereof is omitted.

  This comparative example corresponds to the prior art disclosed in Patent Document 1. This comparative example is different from the present embodiment mainly in that the individual displacement portions 4-2 and 6-1 are removed, and the first displacement portion 4 is configured by only the individual displacement portions 4-1, The second displacement portion 6 is composed of only the individual displacement portions 6-2. The individual displacement part 4-1 is composed of the lower SiN film 21 and the upper Al film 22, and the individual displacement part 6-2 is composed of the lower SiN film 32 and the upper Al film 26. The thermal separation unit 5 is composed of a SiN film 32. The length L11 from the start point to the end point of the individual displacement part 4-1 and the length L12 from the start point to the end point of the individual displacement part 6-2 are substantially equal. When the sacrificial layer 20 is finally removed, both the individual displacement portions 4-1 and 6-2 are brought into FIG. 10A at room temperature due to the internal stress of the films 21 and 22 or the stress of the films 32 and 26. As shown, it is curved upward (+ Z direction). When the individual displacement portions 4-1 and 6-2 receive heat and the temperature rises, the degree of upward bending decreases according to the temperature.

  In this comparative example, when a low-temperature object near normal temperature is observed, as shown in FIG. 10A, the individual displacement portion 4-1, and the element temperature at that time (the temperature of the substrate 1) bend upward. On the other hand, the individual displacement part 6-2 curves upward according to the element temperature (temperature of the board | substrate 1) at that time and the temperature by incident infrared rays i. In FIG. 10A, since the low temperature object is observed, the temperatures of the individual displacement part 4-1 and the individual displacement part 6-2 are substantially equal. Therefore, the degrees of curvature of the individual displacement portions 4-1 and the individual displacement portions 6-2 are also substantially equal, and the movable electrode portion 7 is substantially parallel to the fixed electrode 8 formed on the substrate 1.

  In this comparative example, when a high-temperature object having a considerably high temperature is observed, as shown in FIG. 10B, the individual displacement portion 4-1 moves upward according to the element temperature (temperature of the substrate 1) at that time. To curve. On the other hand, the sensor BM curves upward in accordance with the element temperature (temperature of the substrate 1) at that time and the temperature due to the incident infrared ray i. In FIG.10 (b), since the high temperature object is observed, the temperature of the individual displacement part 6-2 becomes quite high with respect to the temperature of the individual displacement part 4-1. Therefore, the degree of curvature of the individual displacement part 6-2 is considerably smaller than the degree of curvature of the individual displacement part 4-1. As a result, the movable electrode portion 7 is tilted as shown in FIG. 10B, and in some cases, the movable electrode portion 7 comes into contact with the fixed electrode portion 8 near the point C in FIG. 10B.

  In this comparative example, even if the amount of incident infrared rays i is large and the movable electrode portion 7 is tilted so as to contact as shown in FIG. 10B, the capacitance between the electrode portions 7 and 8 obtained at that time is In the state where the movable electrode portion 7 is parallel to the fixed electrode portion 8, the same capacitance as that obtained when the distance between the electrode portions 7 and 8 is slightly narrower than the distance d 1 shown in FIG. Only. In other words, the effective distance between the electrode portions 7 and 8 in the case of FIG. 10B is only slightly smaller than the distance d1 shown in FIG. Therefore, the change in capacitance between the electrode portions 7 and 8 becomes small with respect to the change in the amount of incident infrared ray i, and the detection sensitivity of incident infrared ray i is low.

  Further, in this comparative example, in order to avoid the movable electrode portion 7 from contacting the fixed electrode portion 8, the position of the starting point portion of the individual displacement portion 6-2 (that is, the connection portion 5b in FIG. 10) is illustrated. 6 may be shifted in the −X direction (the direction of arrow D in FIG. 10 which is the final state after removing the sacrificial layer 20). However, if it does in this way, the space | interval d1 in Fig.6 (a) will become large. Since the capacitance between the electrode portions 7 and 8 is inversely proportional to the distance d1, the increase in the distance d1 reduces the change in capacitance, and as a result, the detection sensitivity of the incident infrared ray i decreases. End up.

  Further, in this comparative example, as can be seen from the above description, the effective distance between the electrode portions 7 and 8 becomes narrower as the temperature of the object to be observed is higher. Therefore, the higher the temperature of the object to be observed, the greater the change in capacitance and the higher the detection sensitivity. However, normally, since the frequency of use is high near normal temperature, contrary to the comparative example, the detection sensitivity is high near normal temperature and the detection sensitivity is required to decrease as the temperature increases.

  On the other hand, in the present embodiment, as shown in FIG. 5, the distance between the two electrode portions 7 and 8 is always the temperature of the object to be observed while the movable electrode portion 7 is kept parallel to the fixed electrode portion 8. It changes in accordance with (that is, the amount of detection sensitivity of incident infrared ray i). Therefore, according to the present embodiment, compared to the comparative example, the change in the distance between the electrode portions 7 and 8 with respect to the change in the amount of incident infrared rays i is increased, and the detection sensitivity of infrared rays i is increased.

  In the present embodiment, since the movable electrode portion 7 remains parallel to the fixed electrode portion 8, the movable electrode portion 7 does not collide with the fixed electrode portion 8 as shown in FIG. The movable electrode portion 7 can be brought close to the fixed electrode portion 8 so that the distance between the electrode portions 7 and 8 can be very narrowed. Accordingly, the electrostatic capacity between the electrode parts 7 and 8 is inversely proportional to the distance between the two electrode parts 7 and 8, so that the change in the electrostatic capacity increases with a decrease in the distance. The detection sensitivity of i can be increased.

  Furthermore, in the present embodiment, as shown in FIG. 5, contrary to the comparative example, the distance between the movable electrode portion 7 and the fixed electrode portion 8 is set when the temperature of the object to be observed is low near normal temperature. Is narrow and spreads as the temperature increases. Therefore, it is preferable because the sensitivity can be increased in the vicinity of room temperature, which is the most frequently used.

  In this embodiment, as can be seen from FIG. 5, the movable electrode portion 7 moves in the X-axis direction according to the temperature of the object to be observed, the environmental temperature, and the like. Therefore, even if the movable electrode portion 7 moves in the X-axis direction in this way, the fixed electrode has a margin so that the movable electrode portion 7 does not protrude from the fixed electrode portion 8 in a plan view seen from the Z-axis direction. It is preferable to set the size and arrangement of the portion 8.

  [Second Embodiment]

  FIG. 11 is a schematic plan view schematically showing a unit pixel (unit element) of the radiation detection apparatus according to the second embodiment of the present invention. 12 is a schematic sectional view taken along line X17-X18 in FIG. 11, and FIG. 13 is a schematic sectional view taken along line Y17-Y18 in FIG. However, FIGS. 11 to 13 show a state before the sacrificial layer 20 is removed during the manufacture of the radiation detection apparatus according to the present embodiment. The sacrificial layer 20 is shown in FIGS. 12 and 13, but omitted in FIG. Although not shown in the drawing, the schematic cross-sectional view along the line X19-X20 in FIG. 11 is the same as FIG.

  FIGS. 14A and 14B are diagrams schematically showing the completed state of the radiation detection apparatus according to the present embodiment after removing the sacrificial layer 20 in a greatly simplified manner. It corresponds to a visual map. FIG. 14A shows a state in which a thermal equilibrium is reached and the temperature of each part of the substrate and the element reaches T0 when the ambient temperature is normal temperature T0 in a state where a low-temperature object near normal temperature is observed. ing. FIG. 14B shows a state where a high-temperature object having a considerably high temperature is observed when the environmental temperature and the substrate temperature are T0.

  11 to 14, the same or corresponding elements as those in FIGS. 1 to 5 are denoted by the same reference numerals, and redundant description thereof is omitted.

  The difference between the present embodiment and the first embodiment is that, in the first embodiment, the heat separation part 5 is configured in a J shape, whereas in the present embodiment, the heat separation is performed. The portion 5 is configured in a straight line, and only the individual displacement portions 4-1, 4-2, the heat separation portion 5, and the individual displacement portions 6-1, 6-2 are linearly arranged in the X-axis direction. is there. With this arrangement, the direction from the start point to the end point of the first displacement part 4 and the direction from the start point to the end point of the second displacement part 6 are also in the −X direction.

  As can be understood from FIG. 14, the same advantages as those of the first embodiment can be obtained by this embodiment.

  [Third Embodiment]

  FIG. 15 is a schematic plan view schematically showing a unit pixel (unit element) of the radiation detection apparatus according to the third embodiment of the present invention. 16 is a schematic sectional view taken along line X21-X22 in FIG. 15, and FIG. 17 is a schematic sectional view taken along line Y21-Y22 in FIG. 15 to 17 show a state before the sacrificial layer 20 is removed during the production of the radiation detection apparatus according to the present embodiment. The sacrificial layer 20 is shown in FIGS. 16 and 17, but is omitted in FIG. Although not shown in the drawing, the schematic cross-sectional view along the line X23-X24 in FIG. 15 is the same as FIG.

  18 (a) and 18 (b) are diagrams schematically showing the completed state of the radiation detection apparatus according to the present embodiment after removing the sacrificial layer 20 in a greatly simplified manner. It corresponds to a visual map. FIG. 18A shows a state in which a thermal equilibrium is reached and the temperature of each part of the substrate and the element reaches T0 when the ambient temperature is normal temperature T0 in a state where a low-temperature object near normal temperature is observed. ing. FIG. 18B shows a state in which a high-temperature object having a considerably high temperature is observed when the environmental temperature and the substrate temperature are T0.

  15 to 18, elements that are the same as or correspond to those in FIGS. 1 to 5 are given the same reference numerals, and redundant descriptions thereof are omitted.

  The present embodiment is different from the first embodiment in that the leg portion 3 is composed of the SiN film 51 and has a horizontal portion 3a extending in the X-axis direction, thereby increasing the thermal resistance. A narrow Ti wiring layer 52 is formed on the leg 3, and a displacement portion 41 is provided instead of the first and second displacement portions 4 and 6 and the heat separation portion 5 in FIG. It is a point.

  As shown in FIGS. 15 and 16, the displacement portion 41 is mechanically connected sequentially in the + X direction from the −X side end portion (start point portion) to the + X side end portion (end point portion). It is composed of two individual displacement portions 41-1 and 41-2.

  An end portion (starting point portion) on the −X side of the individual displacement portion 41-1 is connected to an end portion on the + X side of the horizontal portion 3a of the leg portion 3 by a connecting portion 41a. The + X side end portion (end point portion) of the individual displacement portion 41-1 is connected to the −X side end portion (start point portion) of the + X side individual displacement portion 41-2 by the connection portion 41ba. The + X side end (end point part) of the individual displacement part 41-2 is connected to the movable electrode part 7 by the connection part 7a.

  As shown in FIG. 16, the individual displacement portion 41-1 is composed of a lower SiN film 53 and an upper Al film 54 that overlap each other. At the stage where the sacrificial layer 20 is not removed, the individual displacement part 41-1 is held by the sacrificial layer 20 and is not curved and extends straight in the X-axis direction in parallel with the substrate 1, as shown in FIG. However, when the sacrificial layer 20 is finally removed by setting the film thicknesses of the films 53 and 54, the film forming conditions at the time of manufacture, and the like, the internal stress of the films 53 and 54 causes the FIG. As shown to a), it curves upwards (+ Z direction, the opposite side to the board | substrate 1). When the individual displacement portion 41-1 receives heat and the temperature rises, the degree of upward bending decreases according to the temperature.

  As shown in FIG. 16, the individual displacement portion 41-2 includes a lower Al film 26 and an upper SiN film 53 that overlap each other. At the stage where the sacrificial layer 20 is not removed, the individual displacement part 41-2 is held by the sacrificial layer 20 and is not curved and extends straight in the X-axis direction in parallel with the substrate 1, as shown in FIG. However, when the sacrificial layer 20 is finally removed by setting the film thicknesses of the films 26 and 53, the film forming conditions at the time of manufacture, and the like, the internal stress of the films 26 and 53 causes the FIG. As shown to a), it curves below (-Z direction, the board | substrate 1 side). When the individual displacement portion 41-2 receives heat and the temperature rises, the degree of downward bending decreases according to the temperature.

  The length L21 from the start point to the end point of the individual displacement part 41-1 and the length L22 from the start point to the end point of the individual displacement part 41-2 are substantially equal.

  According to the present embodiment, it can be understood from FIG. 18 that the movable electrode portion 7 is always parallel to the fixed electrode portion 8.

  Therefore, also in the present embodiment, as in the first embodiment, the movable electrode portion 7 is always parallel to the fixed electrode portion 8, so that both electrode portions 7, The change of the interval of 8 becomes large, and the detection sensitivity of the infrared ray i increases.

  However, in the present embodiment, when the environmental temperature changes, the height of the movable electrode portion 7 changes accordingly. Further, in the present embodiment, the distance between the movable electrode portion 7 and the fixed electrode portion 8 becomes narrower as the temperature of the object to be observed becomes higher. Therefore, the sensitivity cannot be increased near room temperature.

  [Fourth Embodiment]

  FIG. 19 is a schematic plan view schematically showing a unit pixel (unit element) of the radiation detection apparatus according to the fourth embodiment of the present invention. 20 is a schematic sectional view taken along line X25-X26 in FIG. 19, FIG. 21 is a schematic sectional view taken along line X27-X28 in FIG. 19, and FIG. 22 is taken along line Y25-Y26 in FIG. It is a schematic sectional drawing. However, FIGS. 19 to 22 show a state before the sacrificial layer 20 is removed during the manufacture of the radiation detection apparatus according to the present embodiment. The sacrificial layer 20 is shown in FIGS. 20 to 22, but omitted in FIG. Although not shown in the drawing, the schematic cross-sectional view along the line X29-X30 in FIG. 19 is the same as FIG. 21, and the schematic cross-sectional view along the line X31-X32 in FIG. .

  FIGS. 23A and 23B are diagrams schematically showing the completed state of the radiation detection apparatus according to the present embodiment after removing the sacrificial layer 20 in a greatly simplified manner. It corresponds to a visual map. FIG. 23 (a) shows a state in which a thermal equilibrium is reached and the temperature of the substrate and each part of the element reaches T0 when the environmental temperature is normal temperature T0 in a state where a low-temperature object near normal temperature is observed. ing. FIG. 23B shows a state in which a high-temperature object having a considerably high temperature is observed when the environmental temperature and the substrate temperature are T0.

  19 to 23, elements that are the same as or correspond to those in FIGS. 1 to 5 are given the same reference numerals, and redundant descriptions thereof are omitted.

  Although the radiation detection device according to the first embodiment is a capacitance type, the radiation detection device according to the present embodiment is a light readout type modified from the radiation detection device according to the first embodiment. It is.

  In the following description, an example in which the readout light is visible light will be described. However, in the present invention, the readout light may be light other than visible light.

  This embodiment differs from the first embodiment in the following points. In the present embodiment, instead of the movable electrode portion 7, a half mirror portion 61 that reflects only a part of the received read light j is used. Further, the fixed electrode portion 8 is not provided. The half mirror part 61 is comprised by the SiN film | membrane 21 continuously extended as it is via the connection part 7a from the separate displacement part 6-2. However, the half mirror part 61 is composed of, for example, a silicon oxide film serving as a support part, and a metal such as titanium deposited on the film very thinly by a sputtering method or the like so as to obtain a desired reflectance. Can do. Since the SiN film 21 has infrared absorptivity, in the present embodiment, since the half mirror part 61 is composed of the SiN film 21, the half mirror part 61 is also used as an infrared absorbing part. Further, the upper surface itself of the substrate 1 is used as a reflecting portion fixed to the substrate 1 so as to face the half mirror portion 61. A silicon substrate is used as the substrate 1, and the upper surface thereof can be a reflective surface for visible light. However, a reflective film may be formed on the substrate 1.

  In the present embodiment, the readout light j is incident from above, and the infrared ray i is incident from below and passes through the substrate 1. The silicon substrate 1 is transparent to the infrared ray i.

  In the present embodiment, the infrared ray i is incident from the lower side of the substrate 1. The infrared ray made of an Al film or the like is used as a shielding part that shields the infrared ray i from the first displacement part 4 and the heat separation part 5. A light shielding film 62 is formed on the substrate 1 below the first displacement part 4 and the heat separation part 5. However, the infrared light shielding film 62 is not necessarily formed.

  In the present embodiment, since it is an optical readout type, the diffusion layers 10 and 11 and the readout circuit are not formed on the substrate 1. Further, the Ti wiring layer 24 is removed, and no contact hole is formed in the SiN film 21.

  In the present embodiment, as in the first embodiment, as shown in FIG. 23, the distance between the half mirror portion 61 and the upper surface of the substrate 1 changes according to the amount of incident infrared rays i. However, the half mirror part 61 is always parallel to the substrate 1. When the readout light j is incident from above, the reflected light from the upper surface of the substrate 1 interferes with the reflected light from the half mirror unit 61 to become interference light and return upward. Since the intensity of the interference light depends on the distance between the half mirror part 61 and the upper surface of the substrate 1, interference light having an intensity corresponding to the amount of incident infrared rays can be obtained.

  If the half mirror 61 is tilted, the distance between each part of the half mirror 61 and the upper surface of the substrate 1 is different, so that the intensity of the interference light at each part of the half mirror 61 is different. Sensitivity decreases. On the other hand, in the present embodiment, since the half mirror part 61 is always parallel to the substrate 1, the infrared detection sensitivity is increased.

  Here, an example of an imaging apparatus using the radiation detection apparatus according to the present embodiment will be described. FIG. 24 is a schematic configuration diagram showing this imaging apparatus. In FIG. 24, the radiation detection apparatus according to the present embodiment is denoted by reference numeral 100.

  In addition to the radiation detection device 100, this imaging device collects infrared rays i from a readout optical system, a two-dimensional CCD 80 as an imaging means, and a heat source 81 as an observation target (target object) to detect radiation. An infrared imaging lens 82 that forms an infrared image of the heat source 81 is formed on a surface on which the half mirror 61 serving as an infrared absorption unit of the apparatus 100 is distributed.

  In this imaging apparatus, the readout optical system includes an LD (laser diode) 83 that supplies readout light, a first lens system 84 that guides readout light from the LD 83 to all pixels of the radiation detection apparatus 100, and a first lens system 84. A position conjugate with each pixel is formed in cooperation with the lens system 84, and the light beam of the readout light reflected by all the pixels after passing through the first lens system 84 to become interference light is converted into the conjugate state. And a second lens system 86 that leads to the position. The light receiving surface of the CCD 80 is disposed at the conjugate position, and all the pixels and the plurality of light receiving elements of the CCD 80 are in an optically conjugate relationship by the lens systems 84 and 86.

  The LD 83 is arranged on one side (right side in FIG. 24) with respect to the optical axis O of the first lens system 84, and supplies the readout light so that the readout light passes through the region on the one side. In this example, the LD 83 is disposed in the vicinity of the focal plane on the second lens system 86 side of the first lens system 84, and the readout light that has passed through the first lens system 84 becomes a substantially parallel light beam and irradiates all pixels. It is like that. In this example, the radiation detection apparatus 100 is arranged so that the surface of the substrate 1 is orthogonal to the optical axis O.

  According to the imaging apparatus shown in FIG. 24, the light beam bundle 91 of the readout light emitted from the LD 83 is incident on the first lens system 84 and becomes a light beam 92 that is substantially collimated. Next, the substantially collimated beam bundle 92 is incident on all the pixels of the radiation detection apparatus 100 at a certain angle with respect to the normal line of the substrate 1.

  On the other hand, infrared rays from the heat source 81 are collected by the imaging lens 82, and an infrared image of the heat source 81 is formed on the surface on which the half mirror part 61 as the infrared absorption part of the radiation detection apparatus 100 is distributed. The Thereby, infrared rays are incident on the half mirror part 61 as an infrared ray absorbing part of each pixel of the radiation detection apparatus 100. This incident infrared ray is converted into a distance between the half mirror 61 and the upper surface of the substrate 1.

  The light bundle 92 incident on all the pixels becomes interference light and becomes a light bundle 93, and again enters the first lens system 84 from the side opposite to the LD 83 side to become a condensed light beam 94. After condensing at the condensing point of the light beam 94, it becomes a divergent beam 95 and enters the second lens system 86. The divergent light beam 95 incident on the second lens system 86 is made into, for example, a substantially parallel light beam 96 by the second lens system 86 and is incident on the light receiving surface of the CCD 80. Here, since each pixel and the light receiving surface of the CCD 80 are in a conjugate relationship by the lens systems 84 and 86, an image of the pixel is formed at each corresponding portion on the light receiving surface of the CCD 80, and all the pixels as a whole. An optical image which is a distribution image of is formed. The intensity of the image of each pixel depends on the interference intensity of each interference light.

  Therefore, the optical image by the readout light formed on the light receiving surface of the CCD 80 reflects the infrared image incident on the radiation detection device 100. This optical image is picked up by the CCD 80. Instead of using the CCD 80, the optical image may be observed with the naked eye using an eyepiece or the like.

  The above is an example of an imaging device. In FIG. 24, a radiation detecting device having only a single pixel (element) is used as the radiation detecting device 100, and a single light receiving unit is used instead of the two-dimensional CCD 80. If a photodetector having only the above is used, a detection device as a so-called infrared point sensor can be configured. This also applies to each of the embodiments described above.

  Although the embodiments of the present invention have been described above, the present invention is not limited to these embodiments.

  For example, in the present invention, similarly to the case where the radiation detection apparatus according to the fourth embodiment is obtained by transforming the radiation detection apparatus according to the first embodiment into an optical readout type, the second and third configurations are obtained. The radiation detection apparatus according to the embodiment may be modified to an optical readout type.

It is a schematic plan view which shows typically the unit pixel of the radiation detection apparatus by the 1st Embodiment of this invention. It is a schematic sectional drawing in alignment with the X1-X2 line | wire in FIG. It is a schematic sectional drawing in alignment with the X3-X4 line | wire in FIG. It is a schematic sectional drawing in alignment with the Y1-Y2 line | wire in FIG. It is A arrow view in FIG. It is a schematic plan view which shows typically the unit pixel of the radiation detection apparatus by a comparative example. It is a schematic sectional drawing in alignment with the X9-X10 line | wire in FIG. It is a schematic sectional drawing in alignment with the X11-X12 line | wire in FIG. It is a schematic sectional drawing in alignment with line Y9-Y10 in FIG. It is a B arrow line view in FIG. It is a schematic plan view which shows typically the unit pixel of the radiation detection apparatus by the 2nd Embodiment of this invention. It is a schematic sectional drawing in alignment with the X17-X18 line | wire in FIG. It is a schematic sectional drawing in alignment with the Y17-Y18 line | wire in FIG. It is E arrow line view in FIG. It is a schematic plan view which shows typically the unit pixel of the radiation detection apparatus by the 3rd Embodiment of this invention. It is a schematic sectional drawing in alignment with the X21-X22 line | wire in FIG. It is a schematic sectional drawing in alignment with the Y21-Y22 line | wire in FIG. It is F arrow line view in FIG. It is a schematic plan view which shows typically the unit pixel of the radiation detection apparatus by the 4th Embodiment of this invention. It is a schematic sectional drawing in alignment with the X25-X26 line | wire in FIG. FIG. 20 is a schematic cross-sectional view taken along line X27-X28 in FIG. It is a schematic sectional drawing in alignment with the Y25-Y26 line | wire in FIG. It is a G arrow line view in FIG. It is a schematic block diagram which shows an imaging device.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Board | substrate 2 Supported part 4 1st displacement part 4-1, 4-2, 6-1, 6-2 Individual displacement part 5 Thermal separation part 6 2nd displacement part 7 Movable electrode part 8 Fixed electrode part 9 Infrared rays Absorber

Claims (10)

A base and a supported portion supported by the base;
The supported part includes a heat separating part with high thermal resistance, a radiation absorbing part that receives radiation and converts it into heat, and first and second displacement parts,
Each of the first displacement portion and the second displacement portion has a plurality of individual displacement portions,
Each of the plurality of individual displacement portions of the first displacement portion includes at least two layers of different materials having different expansion coefficients,
Each of the plurality of individual displacement portions of the second displacement portion has at least two layers of different materials having different expansion coefficients that overlap each other,
The first displacement part is mechanically continuous with the base without the heat separation part,
The radiation absorbing portion and the second displacement portion are mechanically continuous with the base via the heat separation portion and the first displacement portion,
The second displacement portion is thermally coupled to the radiation absorbing portion;
At least one individual displacement portion of the plurality of individual displacement portions of the first displacement portion is curved toward the base in a predetermined state in which the amount of radiation received by the radiation absorption portion is small,
At least one other individual displacement portion of the plurality of individual displacement portions of the first displacement portion is bent to the opposite side to the base in the state,
At least one individual displacement portion of the plurality of individual displacement portions of the second displacement portion is curved toward the base in the state,
The thermal displacement element, wherein at least one other individual displacement portion of the plurality of individual displacement portions of the second displacement portion bends in the state opposite to the base. The plurality of individual displacement portions of the first displacement portion are mechanically connected sequentially in a predetermined direction from the start point portion of the first displacement portion to the end point portion of the first displacement portion,
The plurality of individual displacement portions of the second displacement portion are mechanically connected sequentially in a predetermined direction from the start point portion of the second displacement portion to the end point portion of the second displacement portion,
The direction from the start point of the first displacement part toward the end point of the first displacement part and the direction from the start point of the second displacement part toward the end point of the second displacement part are substantially The thermal displacement element according to claim 1, wherein the thermal displacement element is reverse. The plurality of individual displacement portions of the first displacement portion are mechanically connected sequentially in a predetermined direction from the start point portion of the first displacement portion to the end point portion of the first displacement portion,
The plurality of individual displacement portions of the second displacement portion are mechanically connected sequentially in a predetermined direction from the start point portion of the second displacement portion to the end point portion of the second displacement portion,
The direction from the start point of the first displacement part toward the end point of the first displacement part and the direction from the start point of the second displacement part toward the end point of the second displacement part are substantially 2. The thermal displacement element according to claim 1, wherein the thermal displacement elements are the same. The number of the plurality of individual displacement portions of the first displacement portion and the number of the plurality of individual displacement portions of the second displacement portion are two, respectively.
Of the plurality of individual displacement portions of the first displacement portion, the individual displacement portion on the start point side of the first displacement portion, and the plurality of individual displacement portions of the second displacement portion. The individual displacement portion on the end point side of the second displacement portion is curved in the state opposite to the base,
Of the plurality of individual displacement portions of the first displacement portion, the individual displacement portion on the end point side of the first displacement portion, and the plurality of individual displacement portions of the second displacement portion. 4. The thermal displacement element according to claim 2, wherein the individual displacement portion on the starting point side of the second displacement portion is curved toward the base in the state. 5. The length from the start point to the end point of each individual displacement part of the first displacement part is substantially equal to each other,
5. The thermal displacement element according to claim 4, wherein the lengths of the individual displacement portions from the start point to the end point of the second displacement portion are substantially equal to each other. With respect to the plurality of individual displacement portions of the first displacement portion, the at least two layers of the individual displacement portion that curves toward the base in the state and the individual displacement portion that curves toward the opposite side to the base in the state. In the at least two layers, the materials constituting each layer are the same and the overlapping order of the layers of each material is reversed,
With respect to the plurality of individual displacement portions of the second displacement portion, the at least two layers of the individual displacement portion that curves toward the base in the state and the individual displacement portion that curves toward the opposite side to the base in the state. 6. The thermal displacement according to any one of claims 1 to 5, wherein the at least two layers are the same in the materials constituting each layer, and the layers are stacked in reverse order. element. A base and a supported portion supported by the base;
The supported portion includes a radiation absorbing portion that receives radiation and converts it into heat, and a displacement portion that has a plurality of individual displacement portions and is thermally coupled to the radiation absorbing portion,
Each of the plurality of individual displacement portions has at least two layers of different materials having different expansion coefficients,
The plurality of individual displacement portions are mechanically connected sequentially in a predetermined direction from the start point portion of the displacement portion to the end point portion of the displacement portion,
At least one individual displacement portion of the plurality of individual displacement portions is curved toward the base in a predetermined state in which the amount of radiation received by the radiation absorption portion is small,
The at least one other individual displacement portion among the plurality of individual displacement portions is curved in the above state to the side opposite to the base body.   The thermal displacement element according to any one of claims 1 to 6, and a displacement reading member fixed to the second displacement portion, and a predetermined value corresponding to the displacement generated in the second displacement portion. A radiation detection apparatus comprising a displacement readout member used to obtain a change in the above.   The displacement reading member is a half mirror portion that reflects only a part of the received reading light, and includes a reflecting portion fixed to the base so as to face the half mirror portion. Item 9. The radiation detection apparatus according to Item 8.   9. The radiation detection apparatus according to claim 8, wherein the displacement reading member is a movable electrode part, and includes a fixed electrode part fixed to the base so as to face the movable electrode part.

Images