JPH11223556A - Optical readout type radiation-displacement converter and its manufacture - Google Patents

Abstract

PROBLEM TO BE SOLVED: To improve the radiation detecting accuracy and sensitivity of an optical readout type radiation-displacement converter without using any cooler and to secure the sufficient strength of the structure of the converter itself and, at the same time, to simplify the manufacturing process of the converter. SOLUTION: A section 3 to be supported is supported by a substrate 1 through a leg section 2. The section 3 is provided with an infrared absorbing film 4 which converts infrared rays into heat upon receiving the infrared rays and displacing section 4 and 5 which are displaced against the substrate 1 on the principle of a bimetal in accordance with the heat generated from the film 4. A reflecting film 5 receives readout light (j) and emits the reflected light of the readout light (j) by changing the reflecting direction and reflecting position in accordance with the displacement of the displacing sections 4 and 5. Of the layers 4 and 5 constituting the section 3, at least one layer 4 is formed continuously to the leg section 2 so that the layer 4 may constitute the section 2.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a technique for detecting various kinds of radiation including invisible light such as infrared rays, X-rays, and ultraviolet rays, and more particularly, to an optical readout for converting radiations into optically readable displacements. TECHNICAL FIELD The present invention relates to a mold radiation-displacement conversion device and a manufacturing method thereof.

[0002]

2. Description of the Related Art Recently, research has been actively conducted on the use of physical information other than information obtained only from the visible light region by detecting invisible light such as infrared rays, X-rays, and ultraviolet rays.
It is expected to be applied to various industrial fields. As an example, the use of infrared light will be described.

[0003] Infrared rays are energy radiated from all objects having a temperature existing on the earth.
An object near 0K emits infrared light having a peak of 8 to 12 μm. By using this infrared ray, it is possible to detect the presence, shape, and temperature of the object even in the dark. Therefore, if this infrared light is used, for example, even at night when there is almost no lighting, it is possible to drive the car as if watching the scenery of daytime, and it is also possible for illegal intruders to enter buildings at night without lighting. It can be easily discovered.

[0004] Because of these advantages, various approaches have been taken to detect infrared light, which is invisible light, since Herschel discovered the infrared light around 1800. Nowadays, two types of detectors have been used as infrared detectors, namely, a quantum infrared detector and a thermal infrared detector.

[0005]

However, even with today's advances in optomechatronics technology, infrared detection is not technically easy, and has not yet been widely used in the general public. The reason will be described below separately for the quantum infrared detector and the thermal infrared detector.

[0006] The quantum infrared detector is a detector that converts photon energy (E: hv) of infrared light into electron energy and detects it. The wavelength of infrared rays that is most useful in the general society is 3 to 12 μm, and the photon energy of this infrared ray is about 0.1 to 0.4 eV. This value is almost equal to the thermal energy of electrons in a normal temperature object. They are equal. Therefore, in order to convert only the font energy of incident infrared rays into electron energy,
The effects of the thermal energy of the electrons must be removed. That is, in the quantum infrared detector, it is essential to cool the detector and remove heat energy.

Usually, in order to suppress this thermal energy to a low level, it is necessary to cool the detector to about -200 ° C. (77 K). However, the cooler for this is large in volume and generates mechanical vibration. Life is short and expensive.
Therefore, the infrared camera using the quantum infrared detector cannot be reduced in size and cost, and is not widely used in the general society.

On the other hand, a conventional thermal infrared detector is
Converts the energy of the incident infrared rays into heat energy,
A change in the temperature of the detector is caused, and a change in the physical property value of the detector due to the change is electrically read. For example, in a resistive bolometer, the resistance value changes when the temperature changes.

This conventional thermal infrared detector does not require a large-scale cooler such as a quantum infrared detector, but has a problem in the detection principle itself. That is, in the conventional thermal infrared detector, although a temperature change of the detector due to only the incident infrared ray has to be detected, a current must be supplied to the detector in order to detect the temperature change.

That is, since the detector generates heat (usually called self-heating) due to a current for detecting a temperature change, it is difficult to detect a temperature change due to only incident infrared rays, and the detection accuracy is reduced. Was.

[0011] Further, the conversion part for converting incident infrared rays into thermal energy detects as much as possible a temperature change depending only on the thermal energy generated by the incident infrared rays.
Although supported in a state of floating from the substrate, it is necessary to build a resistance bolometer or the like in the conversion part floating from the substrate, so it is necessary to electrically connect the conversion part and the substrate with a conductive material. is there. However, since the conductive material has an extremely high thermal conductivity, the conventional thermal infrared detector cannot increase the degree of thermal insulation of the conversion part with respect to the substrate, and the detection accuracy also decreases in this regard. And the sensitivity was also reduced.

Further, the conventional thermal infrared detector has a drawback of low sensitivity. In a conventional thermal infrared detector, for example, an object having a resistance change rate of about 2% when the resistance temperature changes by 1 ° C. is used. The rate of conversion to temperature is at most about 1%. Therefore, even if the temperature of the observation object changes by 1 ° C., the resistance changes only by 0.02%.

Furthermore, in the conventional thermal infrared detector, since the obtained electric signal is extremely weak, the electric signal readout circuit is required to have a very high level of low noise, and the circuit scale is large. Was.

The situation described above is not limited to infrared rays, but also applies to other radiations.

It is also desired that the infrared detector has sufficient structural strength, is simple in manufacturing process, and can be provided at low cost.

The present invention has been made in view of the above-described circumstances, and is an optical readout type radiation-to-displacement conversion device used for a radiation detection device having high detection accuracy and high sensitivity without requiring a cooler. Moreover, it is an object of the present invention to provide an optical readout type radiation-to-displacement conversion device which can sufficiently secure its own structural strength and can be provided at a low cost with a simple manufacturing process, and a method for manufacturing the same. Things.

[0017]

According to a first aspect of the present invention, there is provided an optical readout radiation-to-displacement converter, comprising: a base; and a supported base supported on the base via a leg. A supported portion having a radiation absorbing portion that receives radiation and converts it into heat, and a displacement portion that is displaced with respect to the base in accordance with the heat generated by the radiation absorbing portion; And a light acting portion for giving a change to the received readout light in accordance with the displacement of the displacement portion and emitting the changed readout light, the light-reading type radiation-displacement conversion device comprising: At least one of the layers constituting the portion is formed continuously over the leg portion so as to also constitute the leg portion.

According to the first aspect, infrared rays, X-rays,
Radiation such as ultraviolet rays is applied to the radiation absorbing portion of the supported portion, and the radiation is absorbed by the radiation absorbing portion and converted into heat.
The displacement part of the supported part is displaced with respect to the base in accordance with the heat generated in the radiation absorbing part. That is, the incident radiation is converted into a displacement of the displacement unit according to the amount. On the other hand, readout light of visible light or other light is applied to the light action section. The light acting section gives the received reading light a change in accordance with the displacement of the displacement section and emits the changed reading light.As a result, the radiation applied to the radiation absorbing section is converted into a change in the reading light. Will be. Therefore, the radiation can be detected based on the readout light emitted from the light acting section. At this time, since displacement detection by light can be performed with high sensitivity, according to the first aspect, radiation can be detected with high sensitivity. Also,
In the first aspect, unlike the above-described conventional thermal infrared detector, the radiation is not converted into a resistance value (electric signal) through heat, but the radiation is converted into a change in readout light through heat and displacement. Therefore, there is no need to supply current to the supported portion supported by the base, and no self-heating occurs in the supported portion. Therefore, according to the first aspect, since only the heat due to the incident radiation is detected, the detection accuracy is improved. Needless to say, in the first embodiment, a cooler required in the quantum infrared detector is not required, as in the above-described conventional thermal infrared detector. Further, in the first embodiment, since the radiation is not read out as an electric signal, the reading circuit for a weak electric signal which is required in the above-mentioned conventional thermal infrared detector becomes unnecessary.

In the first aspect, at least one of the layers constituting the supported portion is formed continuously over the legs so as to also constitute the legs.
The strength between the supported portion and the leg is greater than when the supported portion and the leg are configured as independent layers,
Sufficient structural strength can be ensured. In addition, since the strength between the supported portion and the leg portion can be increased in this manner, the size of the supported portion can be increased, and the radiation detection sensitivity can be further increased.

Further, according to the first aspect, since at least one of the layers constituting the supported portion and the leg are continuous, the supported portion and the leg are independent of each other. The manufacturing process is simplified and the cost is reduced as compared with the case of forming a layer.

The optical readout type radiation-to-displacement converter according to the first aspect converts radiation into a change in readout light, and its use is necessarily limited to the use of detecting incident radiation. Not something. In the first aspect, the type of incident radiation, the type of readout light, and the like can be appropriately selected depending on the application.

An optical readout radiation-displacement converter according to a second aspect of the present invention is the optical readout radiation-displacement converter according to the first aspect, wherein the at least one layer constitutes the supported portion. This is the layer having the lowest thermal conductivity among the layers to be formed.

As in the second aspect, when the at least one layer is a layer having the lowest thermal conductivity among the layers constituting the supported portion, the thermal conductivity of the legs is reduced. Therefore, the degree of thermal insulation of the supported part from the base can be increased, thereby improving the accuracy and efficiency of radiation conversion, and the radiation detection accuracy and detection sensitivity. Can be improved, which is preferable.

An optical readout radiation-displacement converter according to a third aspect of the present invention is the optical readout radiation-displacement converter according to the first or second aspect, wherein the at least one layer comprises the supported substrate. The layer having the highest Young's modulus among the layers constituting the portion.

As in the third aspect, if the at least one layer is a layer having the largest Young's modulus (that is, a hard layer) among the layers constituting the supported portion, the supported portion and the leg are formed. This is preferable because the strength between the portions is further increased.

An optical readout radiation-displacement converter according to a fourth aspect of the present invention is a method of manufacturing the optical readout radiation-displacement converter according to any one of the first to third aspects, comprising: Forming a sacrificial layer on at least a region of the substrate other than a region where the leg portion contacts the substrate; and forming at least a part of the supported portion on the substrate on which the sacrificial layer is formed. Forming at least one layer that also constitutes the leg portion and also forms the leg portion, the at least one layer being patterned according to the shape of the leg portion and the supported portion, and removing the sacrificial layer. And a stage for performing the operation.

According to the fourth aspect, at least a part of the supported portion can be formed at the same time as the leg, so that the manufacturing can be performed as compared with the case where the leg and the supported portion are formed separately. The process is simplified, and the cost can be reduced.

[0028]

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a perspective view showing an optical readout type radiation-to-displacement converter according to the present invention; In the following description, an example will be described in which the radiation is infrared light and the readout light is visible light. However, in the present invention, the radiation may be X-rays, ultraviolet rays, or other various radiations other than infrared light, May be other light than visible light.

(First Embodiment) First, an optical readout type radiation-to-displacement converter according to a first embodiment of the present invention will be described with reference to FIG.

FIG. 1 is a diagram showing an optical readout type radiation-to-displacement converter according to a first embodiment of the present invention.
FIG. 1A is a diagram schematically illustrating a cross section of the unit pixel (unit element) in a state where the infrared ray i is not incident, and FIG. 1B is a schematic view illustrating a cross section of the unit pixel in a state where the infrared ray i is incident. FIG. 1C is a view taken in the direction of arrows AA ′ in FIG.
FIG. 1D is a plan view showing an arrangement state of the pixels.
It is a top view corresponding to (c).

The radiation-to-displacement conversion apparatus according to the present embodiment includes a substrate 1 as a base and a supported portion 3 supported on the substrate 1 via legs 2 so as to be floated.

In the present embodiment, the supported portion 3
Is provided so that the infrared light i is incident from below the substrate 1 and the readout light j is incident from above the substrate 1. Therefore, the substrate 1 is made of a material that transmits the infrared light i. I have. Specifically, a silicon substrate, a Ge substrate, or the like can be used as the substrate 1. However, when the reading light is incident from below the substrate 1 and the infrared light i is incident from above the substrate 1, the substrate 1 may be made of a material that transmits the reading light. However, the material of the substrate 1 is not limited at all if an opening is formed in a desired region of the substrate 1 where infrared light or readout light passes (region L1 in FIG. 1A).

The supported part 3 is composed of two films (layers) 4 and 5 which are overlapped with each other. The lower film 4 is an infrared absorbing portion that receives infrared rays and converts them into heat.
The film 4 and the film 5 are made of different materials having different expansion coefficients, and constitute a so-called thermal bimorph structure. Therefore, in the present embodiment, the films 4, 5
Constitutes a displacement portion that displaces with respect to the substrate 1 in response to heat generated in the film 4 as an infrared absorbing portion. As described later, the membranes 4 and 5 constitute a cantilever,
When the expansion coefficient of the lower film 4 is larger than the expansion coefficient of the upper film 5, the heat causes the heat to bend upward and incline as shown in FIG. Conversely, the expansion coefficient of the lower film 4 may be smaller than the expansion coefficient of the upper film 5, and in this case, the heat causes the film to curve downward and tilt.
Further, in the present embodiment, the upper film 5 has the read light j
And a light action unit that receives the readout light j, gives a change to the received readout light according to the displacement of the displacement unit, and emits the changed readout light. I have. That is, the film 5 as the reflecting portion is
The readout light j is received, and the received readout light is given a change in the reflection direction and a change in the reflection position in accordance with the displacement of the films 4 and 5 as the displacement portions, and the changed readout light is emitted as reflected light.

As can be seen from the above description, in the present embodiment, the film 4 also serves as a part of the displacement part and the infrared absorbing part, and the film 5 is used as the other part of the displacement part and the readout as the light acting part. The light reflector is also used. In other words, the infrared absorption part forms a part of the displacement part, and the readout light reflection part forms a part of the displacement part. Therefore, the structure is simple and inexpensive. In the present embodiment, the film 5, which is the readout light reflecting portion as the light acting portion, naturally forms a part of the supported portion 3 and is displaced in accordance with the displacement of the displacement portion. In the present embodiment, the material of the film 4 is, for example, gold black, ceramics (for example, ZrO ₂ , MnO ₂ ,
FeO ₃ , CoO, CuO, Al ₂ O ₃ , MgO, SiO ₂
, A positive resist, a negative resist, graphite (carbon), SiN, or the like. Examples of the material of the film 5 include Al, Ag, and Mg.
O and the metals listed in Table 1 described below can be used.

However, the infrared absorbing portion may be used as a part of the displacement portion, and the reading light reflection portion may be independent of the displacement portion. In this case, for example, the supported portion 3
Is formed by laminating three films, the lower film is made of the same material as the film 4, the upper film is made of the same material as the film 5, and the intermediate film is the lower film. The film may be made of a material having an expansion coefficient different from that of the material of the film. Also,
The infrared absorbing section may be independent of the displacement section, and the readout light reflection section may also be used as a part of the displacement section. In this case, for example, the supported portion 3 is formed by stacking three films, the lower film is formed of the same material as the film 4, and the upper film is formed of the same material as the film 5. In this case, the intermediate film may be made of a material having an expansion coefficient different from that of the material of the upper film. Further, the infrared absorbing section may be independent of the displacement section, and the readout light reflecting section may be independent of the displacement section. In this case, for example, the supported portion 3 is formed by stacking four films, the lowermost film is formed of the same material as the film 4, and the uppermost film is formed of the same material as the film 5. The two intermediate films may be made of different materials having different coefficients of expansion. As a material of the intermediate two films, for example, a metal material listed in Table 1 below, which is known as a bimetal material, may be used. The material of the two intermediate films is, for example, a metal film (Zn, Cd, Pb, M
g, Al, Ni, W, Pt, etc.) and an insulating film (SiO ₂ ,
SiN, polyimide, etc.)
A combination of an insulating film and another insulating film may be used, or a semiconductor film (polysilicon, a-Si, I
nSb, HgCdTe, etc.).

[0036]

[Table 1]

In this embodiment, as shown in FIG. 1, one end of the supported portion 3 is supported by the substrate 1 via the leg portion 2 so that the supported portion 3 separates the gap 6 from the substrate 1. It has a structure floating apart, and the displacement part composed of the films 4 and 5 constitutes a cantilever. Since the supported portion 3 floats from the substrate 1 in this manner, the thermal resistance between the supported portion 3 and the substrate 1 is increased.

In this embodiment, the lower layer 4 of the layers (films) 4 and 5 constituting the supported portion 3 is
Are formed continuously over the leg portion 2. That is, the lower film 4 and the leg 2 constituting the supported portion 3 are commonly formed of the same material. However, in the present invention, the upper layer 5 of the layers 4 and 5 constituting the supported portion 3 may also constitute the leg 2 as in a second embodiment described later, All of the layers 4 and 5 constituting the supported portion 3 may also constitute the leg 2. When the supported portion 3 is composed of three or more layers as described above, at least one of the layers may constitute the leg portion 2.

Here, one or more of the layers constituting the supported portion 3 also constituting the leg portion 2 are the same as the layer having the lowest thermal conductivity among the layers constituting the supported portion 3. Is preferred. In this case, since the thermal conductivity of the leg portion 2 is reduced, the degree of thermal insulation of the supported portion 3 from the substrate 1 can be increased. Therefore, it is difficult for the thermal energy to escape from the supported portion 3, and the temperature of the film 4 is increased even by the slight incidence of infrared light, and the infrared light detection sensitivity is increased.

One or more of the layers constituting the supported portion 3 also constituting the leg 2 have the largest Young's modulus among the layers constituting the supported portion 3 (that is, the hardest layer). )
It is preferable to form a layer in order to further increase the strength between the supported portion and the leg portion.

In this embodiment, as shown in FIG. 1D, the films 4 and 5 and the leg 2 are used as unit pixels (unit elements), and the pixels are two-dimensionally arranged on the substrate 1. I have.
Needless to say, the pixels may be arranged one-dimensionally on the substrate 1 as necessary, or if only the intensity of radiation is to be detected, only a single pixel may be arranged on the substrate 1. You may.

Next, the optical readout type radiation-to-displacement converter shown in FIG. 1 can be manufactured by using, for example, a semiconductor manufacturing process. One example of the manufacturing method will be described with reference to FIG. FIG. 2 is a schematic cross-sectional view showing each step of the manufacturing method, and shows a cross section corresponding to FIG.

First, a polyimide film (for example, a resist) 12 (for example, 1 μm thick) as a sacrificial layer is deposited on the entire surface of a silicon substrate 11 corresponding to the substrate 1 by spin coating or the like. Holes (openings) 12a are made in the polyimide film 12 at positions corresponding to the legs 2 by photolithography (FIG. 2A).

Next, a gold black 14 (for example, having a thickness of 100 mm) corresponding to the film 4 below the leg 2 and the supported portion 3 is formed on the entire surface of the polyimide film 12 so as to fill the hole 12a.
0 Å) by vapor deposition. Further, aluminum 15 (for example, a thickness of 1000 Å) corresponding to the film 5 above the supported portion 3 is deposited on the gold black 14 by a sputtering method. Thereafter, the gold black 14 and the aluminum 15 are patterned by a photolithographic etching method according to the shapes of the films 4 and 5 (FIG. 2B).

Next, although not shown in the drawings, FIG.
The substrate in the state shown in (b) is divided into individual chips by dicing or the like. In this dicing, a force is applied by spraying water or the like. However, since each of the films 14 and 15 is supported and fixed by the polyimide film 12 as a sacrificial layer, the films 14 and 15 are deformed or damaged. There is no danger.

Finally, the polyimide film 12 as a sacrificial layer is removed by an ashing method or the like (FIG. 2C). Thus, the optical readout radiation-displacement converter shown in FIG. 1 is completed. The removal of the polyimide film 12 may be performed by a wet etching method, a dry etching method, or the like.
When the polyimide film 12 is removed by a wet etching method, the etchant may be rinsed and then dried by a solidification sublimation method or the like. The reason for using the solidification sublimation method is to prevent a portion corresponding to the lower layer of the supported portion of the film 14 from coming into contact with the substrate 11 by the capillary force.

Each of the steps of the manufacturing method described above is an application of the well-known semiconductor fine processing technology itself. According to this manufacturing method, the optical readout radiation-displacement converter shown in FIG. 1 is easily manufactured. be able to. Particularly, in the present embodiment, by forming the gold black 14, a portion corresponding to a part of the leg portion 2 and the supported portion 3 (that is, the lower layer 4) is formed at the same time. As compared with the case where the leg portion 2 and the supported portion 3 are separately formed, the manufacturing process is simplified, and the cost can be reduced. Further, during the manufacturing, the displacement parts (gold black 14 and aluminum 15) constituting the supported part 3 are not covered with the sacrificial layer (polyimide film 1).
Since the sacrifice layer is supported and fixed until 2) is removed, there is no defect that the displacement portion is deformed or damaged.

As described above, in the optical readout type radiation-to-displacement converter shown in FIG. 1, the film 4 also serves as a part of the displacement part and the infrared absorption part, and the film 5 is another part of the displacement part. And also serves as a readout light reflection part as a light action part,
One or both of the reading light reflecting portion (reading light reflecting film) and the infrared absorbing portion (infrared absorbing film) may be independent of the films 4 and 5. The optical readout radiation-displacement converter in this case also includes a step of forming one or both of the readout light reflection film and the infrared absorption film in the same manner as the films 4 and 5 in the manufacturing method shown in FIG. It can be manufactured by the manufacturing method described above.

According to the optical readout radiation-displacement converter according to the first embodiment shown in FIG. 1 described above, infrared rays i are incident from below in FIG. This infrared light i
The light passes through the substrate 1 and is absorbed by the film 4 also serving as an infrared absorbing portion and converted into heat. As shown in FIG.
The films 4 and 5, which also serve as displacement parts, are curved upward and inclined in accordance with the heat generated in the step (1). That is, the incident infrared light i
The displacement is converted into the displacement of the films 4 and 5 according to the amount. On the other hand, the readout optical system described later
Is incident on the film 5 from above in FIG. The film 5 changes the reflection direction and the reflection position in accordance with the displacement, and emits the changed read light as reflected light, so that the infrared light radiated to the film 4 eventually becomes the reflected light of the read light. Will be transformed into changes. Therefore, as described later, infrared light can be detected based on the reflected light of the read light reflected by the film 5. At this time, since displacement detection by light can be performed with high sensitivity, according to the present embodiment, infrared rays can be detected with high sensitivity. Further, in the present embodiment, the infrared rays are not converted into a resistance value (electric signal) through heat, but are converted into changes in the readout light through heat and displacement. There is no need to supply a current to the portion 3, and no self-heating occurs in the supported portion 3. Therefore, according to the present embodiment, since heat is detected only by the incident infrared rays, S
/ N is improved, and the detection accuracy is improved. Needless to say, in the present embodiment, the cooler that was required in the quantum infrared detector is not required. Further, in the present embodiment, since infrared light is not read out as an electric signal, a readout circuit for a weak electric signal which is necessary in a conventional thermal infrared detector becomes unnecessary.

In the first embodiment shown in FIG. 1, at least one of the layers 4 and 5 constituting the supported portion 3 is applied to the leg 2 so that the layer 4 also constitutes the leg 2. Since it is formed continuously, the strength between the supported portion 3 and the leg 2 is increased as compared with a case where the supported portion 3 and the leg 2 are formed of independent layers, and the structure is improved. Sufficient strength can be ensured. Further, since the strength between the supported portion 3 and the leg portion 2 can be increased in this manner, the size of the supported portion 3 can be increased, and the detection sensitivity of infrared rays can be further increased. .

Further, according to the present embodiment, at least one of the layers 4 and 5 constituting the supported portion 3 and the leg portion 2 are continuous with each other. The manufacturing process is simplified and the cost is reduced as compared with the case where the part 2 and the part 2 are constituted by independent layers.

(Example of Imaging Apparatus) Next, an example of an imaging apparatus using the optical readout type radiation-to-displacement converter according to the first embodiment will be described with reference to FIG. FIG. 3 is a schematic configuration diagram illustrating an imaging device according to the present example.

The imaging device according to this embodiment is a light-reading type radiation-to-displacement conversion device shown in FIG. 1 according to the first embodiment (indicated by reference numeral 100 in FIG.
The upper and lower directions in (a) correspond to the right and left directions in FIG. 3, respectively. ), An infrared imaging lens 20 for condensing the infrared light i to form an infrared image on the surface of the converter 100 on which the film 4 as the infrared absorbing portion is distributed, The readout light is applied to each of the films 5 as the reflection portions of the elements (pixels), and the films 4 and 5 as the displacement portions of the respective elements are formed based on the reflected light of the readout light reflected by the film 5 of the respective elements. A readout optical system for forming an optical image corresponding to the displacement of the two-dimensional CCD, and two-dimensional CCDs 21, 22, 23 as imaging means for capturing the optical image
And

More specifically, the imaging apparatus according to the present embodiment includes a white light source 24 such as a white lamp, and lenses 25 and 2.
6, 27, 28, beam splitters 29, 30, total reflection mirror 31, R light reflection dichroic mirror 32 and B
A light reflecting dichroic mirror 33 is provided, and these constitute the readout optical system. In this example, the readout optical system is configured to form the optical image using interference. The surface of the conversion device 100 on which the film 5 as a reflection section is distributed and the light receiving surfaces of the CCDs 21 to 23 are arranged at conjugate positions with respect to the lenses 25, 26 to 28. The CCDs 21 to 23, the lenses 26 to 28, and the dichroic mirrors 32 and 33 are
A three-plate CCD camera for visible light is configured. In addition,
An illumination lens may be appropriately disposed between the white light source 24 and the beam splitter 29.

In this embodiment, the infrared rays i are condensed by the imaging lens 20 and an infrared image is formed on the surface of the converter 100 on which the film 4 as the infrared absorbing portion is distributed. As a result, the films 4 and 5 of each pixel are displaced in accordance with the amount of incident infrared light on the film 4 of each pixel of the conversion device 100, as described with respect to the first embodiment.

On the other hand, the light emitted from the white light source 24 is reflected by the beam splitter 29, reaches the beam splitter 30 via the lens 25, passes through the beam splitter 30, and is read by the reading light emitted to the conversion device 100. The total reflection mirror 3 reflected by the beam splitter 30
The light beam is split into a reference beam and a reference beam traveling toward 1. The reading light applied to the conversion device 100 is applied to the film 5 of each pixel of the conversion device 100.
And is transmitted through the beam splitter 30 toward the lens 25. On the other hand, the reference light is reflected by the total reflection mirror 31.
And is further reflected by the beam splitter 30 toward the lens 25. Therefore, the read light reflected by the film 5 of each pixel and the reference light reflected by the total reflection mirror 31 are combined by the beam splitter 30.
The two combined lights are strengthened or weakened according to the phase difference based on the principle of interference to become interference light. Therefore, this interference light is transmitted to the film 5 of each pixel of the conversion device 100.
Has a light intensity of a distribution in which the spectral distribution is shifted with respect to the original white light source 24 in accordance with the displacement amount of (the interference color distribution corresponding to the displacement amount of the film 5 of each pixel). A), the light passes through the lens 25 from the beam splitter 30 to the right in FIG. 3, and further passes through the beam splitter 29.
The interference light transmitted through the beam splitter 29 is color-separated by dichroic mirrors 32 and 33, and an optical image of the R light component of the interference light is transmitted through a lens 27 to a CCD.
An optical image formed by the B light component of the interference light is formed on the CCD 23 through the lens 28,
The optical image of the G light component of the interference light is
Are formed on the CCD 21 via the
Images are taken by 21, 22, and 23. In this way,
The incident infrared image is converted into a visible image, and the visible image is captured.

In the present embodiment, the visible image is stored in the CCD 2
Although the images are taken at 1, 22, and 23, the visible image may be observed with the naked eye. In this case, for example, FIG.
, Dichroic mirrors 32 and 33, lens 2
7, 28 and the CCDs 21 to 23 are removed, and the CCD 21 is removed.
The visible image formed at the position may be observed with the naked eye.

Further, instead of the white light source 24, a monochromatic light source such as a laser may be used. In this case, since an interference image having a distribution of a change in intensity corresponding to the displacement of the film 5 of each pixel of the conversion device 100 at that wavelength can be obtained, a monochrome CCD camera may be used. Specifically, for example, in FIG. 3, dichroic mirrors 32 and 33,
The lenses 27 and 28 and the CCDs 22 and 23 may be removed. Also in this case, the CCD 21 is removed and the CCD 2 is removed.
The monochromatic visible image formed at the position 1 may be observed with the naked eye. Note that, instead of the white light source 24, two light sources having different wavelengths are used.
When a light source that emits a single type of monochromatic light is used, an optical path length difference can be determined even in the case of interference that is not understood by monochromatic light and that is shifted by one or more cycles.

By the way, if the displacement range of the films 4 and 5 is not limited as the displacement portion of the conversion device 100, the intensity of interference is such that the difference in optical path length repeats the intensity every half of the wavelength of the read light. When an infrared ray having a higher intensity is incident, an inversion phenomenon occurs in which the intensity of the interference is inverted. Therefore, it is preferable to limit the range of the displacement of the films 4 and 5 to 以下 or less of the wavelength of the reading light so that the change of the interference intensity due to the displacement of the films 4 and 5 becomes monotonous. For example, if the films 4 and 5 are bent downward in FIG. 1A when the temperature rises, and the distance between the film 4 and the upper surface of the substrate 1 is set to １ ／ or less of the wavelength of the read light, Even if excessive infrared rays are incident, the movement of the films 4 and 5 stops at the point where the free end of the film 4 and the upper surface of the substrate 1 are in contact. Note that the total reflection mirror 31 needs to be positioned at an appropriate position. The above is the light source 24
In the case where a white light source is used as the light source 24, similarly, the change of the interference color due to the displacement of the films 4 and 5 becomes a monotonous change. What is necessary is just to limit the range of displacement. Needless to say, a special restricting portion for restricting the range of displacement of the films 4 and 5 may be provided.

Note that, instead of the lens 25 and the total reflection mirror 31, a commercially available interference objective lens may be used.

By the way, the optical readout type radiation shown in FIG.
The displacement conversion device 100 (a conversion device shown in FIG. 5 to be described later, an optical readout radiation-displacement conversion device shown in FIG. 7, and FIG. 8)
The same applies to the conversion device shown in FIG. 4) is preferably housed in a container 110 in which the inside 110a is evacuated as shown in FIG. When the conversion device 100 is accommodated in the vacuum container 110 in this way, the heat insulation performance is improved, the temperature rise of the films 4 and 5 due to infrared rays increases, and the temperature change of the substrate 1 with respect to an external temperature change is reduced. it can. Further, in order to suppress a change in the temperature of the substrate 1 of the conversion device 100, a thermoelectric temperature stabilizer 111 capable of generating or absorbing heat, such as a Peltier element, is brought into close thermal contact with the container 110 to perform temperature control. Is also effective.

FIG. 4A shows that the conversion device 1 is
FIG. 2 is a cross-sectional view schematically showing a state in which a container 110 is accommodated.
It is attached to. On the incident side of the infrared ray i of the container 110, a window 112 for cutting unnecessary light and maintaining a vacuum in the inside 110a is attached. On the incident side of the reading light j of the container 110, a window 113 for cutting unnecessary light and keeping the inside 110a in a vacuum is attached. The inside 110a of the container 110 is evacuated to a vacuum.

FIG. 4B is a view taken along the line BB ′ in FIG. 4A. Note that the thermoelectric temperature stabilizer 111 is arranged so as not to hinder the incidence of the reading light j.

Although not shown in the drawings, for example,
A temperature sensor is provided in contact with the conversion device 100 or in the substrate 1 of the conversion device 100, and the temperature of the thermoelectric temperature stabilizer 111 is controlled using a detection signal from the temperature sensor.

In the imaging apparatus shown in FIG. 3 (the same applies to an imaging apparatus shown in FIG. 10 to be described later), the whole optical system including the optical readout type radiation-displacement conversion apparatus is supported when used. It is desirable to put in a vibration-proof container that does not resonate at the mechanical resonance frequency of the part 3.

(Second Embodiment) Next, a second embodiment of the present invention will be described.
An optical readout type radiation-to-displacement converter according to the embodiment will be described with reference to FIG.

FIG. 5 is a diagram showing an optical readout type radiation-to-displacement converter according to the present embodiment, and corresponds to FIG. 1 (a). 5, elements that are the same as or correspond to elements in FIG. 1 are given the same reference numerals, and descriptions thereof are omitted.

The difference between the converter shown in FIG. 5 and the converter shown in FIG. 1 is that, in this embodiment, the lower layer 4 of the layers (films) 4 and 5 constituting the supported part 3 is different. The only difference is that the upper layer 5 is formed continuously over the leg 2 so as to also constitute the leg 2. That is, in the present embodiment, the upper film 5 and the leg 2 constituting the supported portion 3 are commonly formed of the same material.

Next, an example of a method for manufacturing the optical readout type radiation-to-displacement converter shown in FIG. 5 will be described with reference to FIG. FIG. 6 is a schematic cross-sectional view showing each step of the manufacturing method, and shows a cross section corresponding to FIG. 6, elements that are the same as or correspond to elements in FIG. 2 are given the same reference numerals.

First, a polyimide film (eg, a resist) 12 (eg, 1 μm thick) as a sacrificial layer is deposited on the entire surface of a silicon substrate 11 corresponding to the substrate 1 by spin coating or the like. Thereafter, on this polyimide film 12, gold black 1 corresponding to the film 4 below the supported portion 3 is formed.
4 (eg, 1000 Angstroms thick) is deposited by evaporation. Next, the gold black 14 is patterned according to the shape of the supported portion 3 by a photolithographic etching method (FIG. 6A).

Next, holes (openings) are formed in the polyimide film 12 at locations corresponding to the legs 2 by photolithographic etching. Thereafter, aluminum 15 (e.g., a thickness of 1000 Å) corresponding to the film 5 above the leg 2 and the supported portion 3 is coated on the entire surface of the gold black 14 and the polyimide film 12 so as to fill the hole. It is applied by a sputtering method. Further, this aluminum 15 is patterned according to the shape of the leg portion 2 and the supported portion 3 by a photolithographic etching method (FIG. 6B).

Thereafter, although not shown in the drawing, FIG.
The substrate in the state shown in (b) is divided into individual chips by dicing or the like.

Finally, the polyimide film 12 as a sacrificial layer is removed by an ashing method or the like (FIG. 6C). Thus, the optical readout radiation-displacement converter shown in FIG. 5 is completed. The removal of the polyimide film 12 may be performed by a wet etching method, a dry etching method, or the like.

According to this embodiment, advantages similar to those of the first embodiment can be obtained.

(Third Embodiment) Next, a third embodiment of the present invention will be described.
An optical readout type radiation-to-displacement converter according to the embodiment will be described with reference to FIG.

FIG. 7 is a diagram showing an optical readout type radiation-to-displacement converter according to the present embodiment. FIG. 7B is a diagram schematically illustrating a cross section of the unit pixel in a state where the infrared rays i are incident thereon.
FIG. 8C is a view taken in the direction of arrows CC ′ in FIG. 7, elements that are the same as or correspond to elements in FIG. 1 are given the same reference numerals, and descriptions thereof are omitted.

The difference between the converter shown in FIG. 7 and the converter shown in FIG. 1 is that, in the converter shown in FIG. 1, the displacement portion composed of the membranes 4 and 5 constitutes a cantilever. In the conversion device shown in FIG. 7, only the point that the displacement portion composed of the films 4 and 5 forms a diaphragm.

The converter shown in FIG. 7 according to the present embodiment can be used similarly to the converter shown in FIG.
For example, the conversion device according to the present embodiment is also the same as that shown in FIG.
Can be used in place of the conversion device shown in FIG.

While the converter shown in FIG. 1 is curved and tilted in response to heat, the converter shown in FIG. 7 is curved in response to heat and has a curvature as shown in FIG. 7B. change. In addition, the reflecting portion as the light acting portion may be limited to a predetermined part instead of the entire deformed portion.

The converter shown in FIG. 7 can be manufactured by the same manufacturing method as that shown in FIG.

In the present embodiment, the lower film 4 and the leg 2 constituting the supported part 3 are similar to the converter shown in FIG.
Are commonly formed of the same material, but the upper film 5 and the leg 2 constituting the supported portion 3 are commonly formed of the same material, similarly to the conversion device shown in FIG. Needless to say, this may be done.

(Fourth Embodiment) Next, a fourth embodiment of the present invention will be described.
An optical readout type radiation-to-displacement converter according to the embodiment will be described with reference to FIG.

FIG. 8 is a diagram showing an optical readout type radiation-to-displacement converter according to the present embodiment. FIG. 8 (a) is a partially cutaway plan view schematically showing the converter, and FIG. 8 (b). FIG. 9 is a view taken along the line DD ′ in FIG.

The radiation-to-displacement converter according to the present embodiment includes a substrate 201 as a base, and a supported portion 203 supported on the substrate 201 via legs 202 so as to be floated.

In this embodiment, the supported portion 203 is provided on the substrate 201, and infrared rays i are incident from below the substrate 201, and read light j is emitted from above the substrate 201.
₀ is incident, the substrate 201
Is made of a material that transmits infrared rays i. Specifically, as the substrate 201, a silicon substrate, a Ge substrate, or the like can be used. However, when the reading light j ₀ from below the substrate 201 infrared i is incident from above the substrate 201 while being incident, a material that transmits readout light it is sufficient to constitute the substrate 201. In this case, for example, an infrared absorption film
The half mirror unit 208 described later is formed on the upper surface of the
9 may be a half mirror. However, the substrate 201
The material of the substrate 201 is not limited in any way as long as an opening is formed in a desired region through which infrared light or readout light passes.

The supported portion 203 is composed of two overlapping films 204 and 2 of different materials having different expansion coefficients.
05. The films 204 and 205 constitute a so-called thermal bimorph structure. The films 204 and 205 may be made of arbitrary materials having different expansion coefficients.
For example, as the material of the films 204 and 205, a metal material listed in Table 1 described above, which is known as a bimetal material, may be used. On the lower surface of the lower film 204, an infrared absorbing film 2 made of the same material as the film 4 in FIG.
07 is formed. In the present embodiment, the film 204,
205 constitutes a displacement unit 206 that displaces with respect to the substrate 201 according to heat generated in the infrared absorption film 207. As described later, since the displacement portion 206 forms a cantilever, the expansion coefficient of the lower film 204 is higher than that of the upper film 2.
If the expansion coefficient is larger than the expansion coefficient of the upper film 205, it is curved upward and inclined by the heat. If the expansion coefficient of the lower film 204 is smaller than the expansion coefficient of the upper film 205, it is curved downward and inclined by the heat. Will do.

The film 204 forming a part of the displacement section 206 is similar to the optical readout type radiation-displacement conversion apparatus shown in FIG.
And the infrared absorbing film 207 may be used as a single film.

[0088] The supported portion 203 has also a half mirror 208 which reflects only a portion of the read-out light j _0. The half mirror unit 208 is fixed to the free end side of the displacement unit 206, and is displaced according to the displacement of the displacement unit 206. An area on the substrate 201 facing the half mirror section 208 is provided with the half mirror section 20.
A total reflection mirror 209 is formed as a reflection unit that reflects the readout light transmitted through the mirror 8.

As shown in FIG. 8B, the read light j ₀
There made incident on the half mirror unit 208, the read light j part becomes reflected light j ₁ is reflected by the half mirror 208 of _0, the remaining reading light j ₀ incident on the half mirror 208 a half mirror 208 And is reflected by the total reflection mirror 209 and again enters the half mirror unit 208 from the lower surface. Part of the readout light that has reentered the half mirror unit 208 from the lower surface is partially reflected by the half mirror unit 2
08 transmitted the transmitted light j ₂ a. Between the transmitted light j ₂ and the reflected light j _1, there is an optical path length difference corresponding to twice the spacing d1 between the half mirror 208 and the total reflection mirror 209. Therefore, interference occurs in response to the optical path length difference between the reflected light j ₁ and transmitted light j _2, the reflected light j ₁ and transmitted light j ₂
Is an interference light having an interference intensity corresponding to the optical path length difference (according to the displacement of the displacement unit 206), and is emitted from the half mirror unit 208. Since the interference intensity of the interference light and the intensity of the transmitted light j ₂ and the intensity of the reflected light j ₁ is strongest when equal, the half mirror unit 2
It is desirable to make the reflectivity of 08 about 38%.

As can be understood from the above description, in the present embodiment, the half mirror section 208 and the total reflection mirror 209
But receives the reading light j _0, constitute an interference means to be emitted instead of the interference light which has an interference state corresponding to the reading light j ₀ which has received the displacement of the displacement portion 206, and thus,
Receiving the reading light j _0, constitute the optical action section for emitting a reading light the change giving change corresponding to the displacement of the displacement portion 206 to the read beam j ₀ that is received.

In this embodiment, as shown in FIG. 8, one end of the supported portion 203 is connected to the substrate 2 via the leg portion 202.
01 supported on the substrate 20
It has a structure that floats from a gap 1 with a gap 210 therebetween, and the displacement portion 206 composed of the films 204 and 205 constitutes a cantilever. In this manner, the supported portion 203 is
, The thermal resistance between the supported portion 203 and the substrate 201 is large.

In the present embodiment, the supported portion 20
The lowermost layer (infrared absorbing film) 207 of the layers (films) 204, 205, and 207 constituting the third layer 3 is formed continuously over the legs 202 so as to also form the legs 202. . That is, the infrared absorbing film 207 and the leg 202 constituting the supported portion 203 are commonly formed of the same material. However, in the present invention, the supported portion 203
Any one or more of the layers 204, 205, and 207 may also constitute the leg 202.

In this embodiment, as shown in FIG. 8A, the displacement section 206, the infrared absorption film 207, the half mirror section 208, the total reflection mirror 209, and the leg section 202 are used as unit pixels (unit elements). The pixels are two-dimensionally arranged on the substrate 201. However, if necessary, the pixels may be arranged one-dimensionally on the substrate 201, or if only the intensity of radiation is to be detected, only a single pixel may be arranged on the substrate 201. You may.

[0094] The conversion device according to this embodiment includes a mask 211 for masking the light other than interference light coming from the half mirror 208 constituting the light acting portion of the reading light j ₀ irradiated ing. The mask 211 has an opening 211a in a region corresponding to the half mirror unit 208. The mask 211 can be formed, for example, by applying a black paint on the readout light incident window 113 provided in the container 110 shown in FIG. 4 that can also accommodate the conversion device according to the present embodiment. . Although the interference light coming from the half mirror unit 208 of the reading light j ₀ to be irradiated is a signal light, the signal other than light of readout light (i.e., noise light) when the mix in the optical signal , So-called S / N is reduced. In this regard,
According to the present embodiment, since the mask 211 is provided, the noise light does not mix with the signal light, and the S / N is improved. However, in the present invention, it is not always necessary to provide the mask 211.

Next, an example of a method for manufacturing the optical readout type radiation-to-displacement converter shown in FIG. 8 according to the present embodiment will be described with reference to FIG. FIG. 9 is a schematic cross-sectional view showing each step of the manufacturing method, and shows a cross section corresponding to FIG.

First, on a silicon substrate 221 corresponding to the substrate 201, a high melting point metal 222 such as titanium (for example, having a thickness of 1000
Angstrom) is deposited by sputtering or the like, and the refractory metal 222 is patterned according to the shape of the total reflection mirror 209. Next, the substrate 221 in this state
A polyimide film 223 (for example, 2.5 μm in thickness) as a sacrificial layer is applied to the entire surface of the
Holes (openings) 22 are formed at positions corresponding to the legs 202 in the polyimide film 223 by photolithography.
Open 3a. (FIG. 9A).

Next, gold black 225 corresponding to the infrared absorption film 207 of the leg portion 202 and the supported portion 203 is formed on the entire surface of the polyimide film 223 so as to fill the hole 223a.
(Eg, 1000 angstroms thick) is deposited by evaporation. Further, a metal 226 corresponding to the film 204 of the supported part 203 (for example,
A metal 227 (for example, a thickness of 1000 Å) corresponding to the film 205 and a thickness of 1000 Å is sequentially deposited by a sputtering method. Thereafter, the gold black 225 and the metals 226, 227 are applied to the film 207,
Patterning is performed by a photolithographic etching method according to the shapes of 204 and 205. Next, the substrate 2 in this state
A silicon oxide film 228 (for example, 2,000 Å in thickness) which is to be a supporting portion constituting a part of the half mirror portion 208 is deposited on the entire surface of the substrate 21 by a plasma CVD method or the like, and the silicon oxide film 228 is Patterning is performed by a photolithographic etching method according to the shape of the mirror section 208. Half mirror part 2
Since the supporting portion (not shown in FIG. 8) of the substrate 08 is formed of the silicon oxide film 228, it is transparent to visible light. Thereafter, a metal 229 (for example, a thickness of 100 Å) such as titanium which is to be a material of a half mirror constituting a part of the half mirror portion 208 is formed on the silicon oxide film 228 or the like so as to obtain a desired reflectance. The metal 229 is patterned according to the shape of the half mirror 208 by a photolithographic etching method (FIG. 9).
(B)).

Finally, the polyimide film 223 is removed by elution with an organic solvent or by performing plasma ashing (FIG. 9C). Thus, the optical readout radiation-displacement converter shown in FIG. 8 is completed.

Each step of the manufacturing method described above is an application of the well-known semiconductor fine processing technology itself. According to this manufacturing method, the optical readout radiation-displacement converter shown in FIG. 8 can be easily manufactured. be able to. In particular, in the present embodiment, by forming the gold black 225, a portion corresponding to a part of the leg portion 202 and the supported portion 203 (that is, a portion corresponding to the infrared absorbing film 207) is formed at the same time. As compared with the case where the part 202 and the supported part 203 are formed separately, the manufacturing process is simplified, and the cost can be reduced. During the manufacturing, the supported portion 2
03 (gold black 225 and metal films 226, 227) are supported and fixed by the sacrificial layer (polyimide film 223) until the sacrificial layer (polyimide film 223) is removed. Not at all.

By the way, usually, 1
A plurality of optical readout radiation-displacement converters are manufactured simultaneously using a single substrate 221. In this case, the devices are divided into individual chips by dicing or the like. The division is preferably performed before the removal of the polyimide film 223 (sacrifice layer), that is, after the stage of FIG. 9B. As described above, if the division into individual chips is performed before the removal of the sacrificial layer, the displacement portions (gold black 225, metal film 22
6,227) is supported and fixed by the sacrificial layer,
The displacement part is not deformed or damaged, and the yield is extremely increased.

According to the radiation-to-displacement conversion device of the present embodiment described above and shown in FIG.
Is incident from below in FIG. This infrared i
Is transmitted through the substrate 201, absorbed by the infrared absorbing film 207, and converted into heat. In response to the heat generated in the infrared absorbing film 207, the displacement portion 206 is curved upward or downward and inclined. That is, the incident infrared light i is converted into a displacement of the displacement unit 206 according to the amount. On the other hand, the reading optical system, which will be described later, the reading light j ₀ of the visible light is irradiated to the half mirror 208 is incident through the opening 211a of the mask 211 from above in FIG. 8 (b). As a result, as described above, the readout light j ₀ incident on the half mirror 208 is varied in the interference light having an interference intensity corresponding to the displacement of the displacement portion 206, the interference light from the half mirror 208 8 It is emitted above (b).
Therefore, as described later, infrared rays can be detected based on the interference light.

In the present embodiment, since the technique for detecting a minute displacement called interference with high sensitivity is applied to the detection of infrared rays, detection with higher sensitivity than before can be performed.
Further, in the present embodiment, similarly to the first embodiment described above, instead of converting infrared rays into a resistance value (electric signal) through heat, the infrared rays are converted into read light through heat and displacement. Since the conversion is performed, it is not necessary to supply a current to the supported portion 203 supported by the substrate 201, and the supported portion 203
Does not generate self-heating. Therefore, according to the present embodiment, since heat is detected only by the incident infrared rays, the S / N is improved and the detection accuracy is improved. Needless to say, in the present embodiment, the cooler that was required in the quantum infrared detector is not required. Further, in the present embodiment, since infrared light is not read out as an electric signal, a readout circuit for a weak electric signal which is necessary in a conventional thermal infrared detector becomes unnecessary.

By the way, the interference light is also obtained in the imaging device shown in FIG. 3 described above, but the interference light is obtained outside the optical readout radiation-displacement conversion device shown in FIG. Therefore, even if uniform infrared rays enter the optical readout type radiation-to-displacement converter 100, the height of the reflective film 5 of each element varies due to the poor flatness of the substrate 1, or the reference light is reflected. If the flatness of the total reflection mirror 31 is not maintained, a signal in which the interference intensity varies for each element is generated even though uniform infrared rays are incident.

In this regard, in the present embodiment, the half mirror section 208 and the total reflection mirror 209 of each element constitute interference means, and are independently provided for each element inside the optical readout type radiation-displacement converter. Since the interference light can be obtained, the uniformity of the output signal of each element is extremely good. In the present embodiment, the optical readout radiation
Since there is no need to configure an interference optical system outside the displacement conversion device, the configuration of the readout optical system is simplified even when the readout optical system is configured according to the principle of interference.

If the range of displacement of the displacement section 206 is not limited, the intensity of the interference repeats the intensity every half of the wavelength of the readout light because the difference in the optical path length repeats. Conversely, an inversion phenomenon in which the interference intensity is inverted occurs. Therefore, it is preferable to limit the range of displacement of the displacement unit 206 to 以下 or less of the wavelength of the read light so that the change in the interference intensity due to the displacement of the displacement unit 206 becomes a monotonous change. For example, if the displacement unit 206 is bent downward in FIG. 8B when the temperature rises, and the interval between the half mirror unit 208 and the total reflection mirror 209 is set to be 1/4 or less of the wavelength of the read light. However, even if excessive infrared rays are incident, the movement of the displacement unit 206 stops at the point where the half mirror unit 208 and the total reflection mirror 209 are in contact with each other.
At this time, since the interference intensity becomes maximum, the inversion phenomenon does not occur. The description so far is based on the case where monochromatic light is used as the readout light. However, even when white light is used as the readout light, similarly, the change of the interference color due to the displacement of the displacement unit 206 becomes a monotonous change. Then, the range of displacement of the displacement unit 206 may be limited. It is needless to say that a special restricting portion for restricting the range of displacement of the displacement portion 206 may be provided.

In the fourth embodiment shown in FIG. 8, the layers 204, 205, 20
7 is formed continuously over the leg portion 202 so as to also constitute the leg portion 202. Therefore, when the supported portion 203 and the leg portion 202 are formed of independent layers, respectively. The strength between the supported portion 203 and the leg portion 202 is increased as compared with the above, and sufficient structural strength can be secured. Further, since the strength between the supported portion 203 and the leg portion 202 can be increased in this manner, the size of the supported portion 203 can be increased, and the detection sensitivity of infrared rays can be further increased. .

Further, according to the present embodiment, at least one layer 207 of layers 204, 205, and 207 constituting supported portion 203 is continuous with leg portion 202. The manufacturing process is simplified and inexpensive as compared with the case where the and the leg portion 202 are constituted by independent layers.

(Another Example of Imaging Apparatus) Next, an example of an imaging apparatus using the optical readout radiation-displacement converter according to the fourth embodiment will be described with reference to FIG. FIG. 10 is a schematic configuration diagram illustrating an imaging device according to the present example.

The imaging device according to the present embodiment is a light-reading type radiation-to-displacement conversion device shown in FIG. 8 according to the fourth embodiment (in FIG.
The upper and lower directions in (b) correspond to the right and left directions in FIG. 10, respectively. ) And an infrared imaging lens 2 for condensing the infrared light i and forming an infrared image on the surface of the converter 300 where the infrared absorption film 207 is distributed.
40, irradiating the said reading light j ₀ respectively to the half mirror portion 208 of each element (pixel) of the converter 300, the of the respective elements based on the coherent light emitted from the half mirror 208 of the elements A readout optical system that forms an optical image according to the displacement of the displacement unit 206.

More specifically, the imaging apparatus according to the present embodiment includes a light source 241, a diaphragm 242 (an illumination lens may be used instead), a beam splitter 243, and lenses 244 and 245. These constitute the readout optical system.

In the present embodiment, the infrared rays i are condensed by the imaging lens 240 and an infrared image is formed on the surface of the converter 300 where the infrared absorbing film 207 is distributed. As a result, the displacement unit 206 of each pixel is displaced in accordance with the amount of incident infrared light on the infrared absorption film 207 of each pixel of the conversion device 300.

[0112] On the other hand, light emitted from the light source 241 is reflected by the beam splitter 243 and enters the converter 300 as a reading light j ₀ through lens 244. As a result, as described in the fourth embodiment, the interference light having the interference intensity corresponding to the displacement of the displacement unit 206 of each element (pixel) is emitted from the half mirror unit 208 of each element toward the lens 244. This interference light is transmitted to the lens 24
4. An optical image is formed by the interference light via the beam splitter 243 and the lens 245, and this is
Observed at In this way, the incident infrared image is converted into a visible image.

It should be noted that instead of observation with the naked eye 246, 2
The optical image may be captured by arranging a dimensional CCD or the like.
In this case, sensitivity variations and offsets can be electrically corrected. Such a situation is the same in the other imaging devices described above. In addition, this CCD
Need not match the number of pixels of the conversion device 300, but it is desirable that the number of pixels be approximately the same.

The readout optical system is not limited to the configuration shown in FIG. Since the conversion device 300 causes interference inside, there is no need for an optical system for causing interference to the outside, and it is sufficient if there is an optical system capable of simply supplying a reading light causing interference and observing the interference intensity. is there. The reading light is not limited to monochromatic light, but may be white light. In the case of white light, the interference intensity is observed as an interference color. Also, if two types of monochromatic light having different wavelengths are used as the readout light, the optical path length difference can be determined even in the case of interference that is not known by monochromatic light and is shifted by one or more cycles. A wide infrared image can be obtained.

In the case where only the intensity of infrared rays is detected instead of imaging an infrared image,
For example, in each of the above-described imaging devices, the optical readout radiation-displacement conversion device is configured to have only one element (pixel), and the readout optical system is left only by a portion related to the element. , An infrared detector can be obtained.

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

[0117]

As described above, according to the present invention,
It is a radiation detection device with high radiation detection accuracy and sensitivity without using a cooler, and can provide its own structural strength sufficiently and can be provided at a simple and inexpensive manufacturing process. An optical readout radiation-displacement conversion device and a method for manufacturing the same can be provided.

[Brief description of the drawings]

FIG. 1 is a diagram showing an optical readout type radiation-displacement conversion device according to a first embodiment of the present invention, and FIG. 1A is a diagram schematically showing a cross section of a unit pixel in a predetermined state; FIG.
(B) is a diagram schematically showing a cross section of the unit pixel in another state,
FIG. 1C is a view taken along the line AA ′ in FIG.
(D) is a plan view showing the arrangement state of the pixels.

FIG. 2 is a diagram illustrating an example of a method of manufacturing the optical readout type radiation-displacement converter illustrated in FIG.

FIG. 3 is a schematic configuration diagram showing an example of an imaging device using the optical readout radiation-displacement conversion device shown in FIG.

FIG. 4 is a diagram schematically showing a state in which a light-reading type radiation-displacement conversion device is housed in a container, FIG. 4 (a) is a cross-sectional view thereof, and FIG. 4 (b) is a view in FIG. FIG.

FIG. 5 is a diagram showing an optical readout type radiation-to-displacement converter according to a second embodiment of the present invention.

6 is a diagram illustrating an example of a method of manufacturing the optical readout type radiation-to-displacement converter illustrated in FIG.

FIG. 7 is a diagram showing an optical readout type radiation-to-displacement converter according to a third embodiment of the present invention, and FIG. 7A is a diagram schematically showing a cross section of a unit pixel in a predetermined state; FIG.
(B) is a diagram schematically showing a cross section of the unit pixel in another state,
FIG. 7C is a view taken along the line CC ′ in FIG. 7A.

FIG. 8 is a diagram showing an optical readout type radiation-to-displacement converter according to a fourth embodiment of the present invention, and FIG. 8 (a) is a partially cutaway plan view schematically showing the converter; FIG. 9B is a view taken along the line DD ′ in FIG.

FIG. 9 is a diagram illustrating an example of a method of manufacturing the optical readout radiation-displacement conversion device illustrated in FIG. 8;

FIG. 10 is a schematic configuration diagram showing an example of an imaging device using the optical readout radiation-displacement conversion device shown in FIG.

[Explanation of symbols]

 Reference Signs List 1,201 Substrate 2,202 Leg 3,203 Supported part 4 Film serving also as part of displacement part and infrared absorption part 5 Film serving also as part of displacement part and reflection part 6,210 Gap 21-23 CCD 31 All Reflection mirror 100 Optical readout radiation-displacement converter 206 Displacement unit 207 Infrared absorbing film 208 Half mirror unit 209 Total reflection mirror 211 Mask

Claims (4)

[Claims] 1. A base, and a supported part supported on the base via a leg,
A supported part having a radiation absorption part that receives radiation and converts it into heat, and a displacement part that displaces with respect to the base in accordance with the heat generated in the radiation absorption part; A light action section that gives a change in accordance with the displacement of the displacement section to the readout light and emits the changed readout light. An optical reading type radiation-displacement conversion device comprising: Wherein at least one of the layers is formed continuously over the legs so as to also constitute the legs.
Displacement converter. 2. The optical readout radiation-displacement converter according to claim 1, wherein the at least one layer is a layer having the lowest thermal conductivity among the layers constituting the supported portion. . 3. The optical read-out type radiation-displacement converter according to claim 1, wherein the at least one layer is a layer having the largest Young's modulus among the layers constituting the supported portion. apparatus. 4. A method for manufacturing an optical readout type radiation-to-displacement conversion device according to claim 1, wherein at least a region of the substrate where at least the leg contacts the substrate. Forming a sacrificial layer in a region excluding the above, and at least one layer constituting at least a part of the supported portion and also constituting the leg on the substrate on which the sacrificial layer is formed. And at least one patterned according to the shape of the leg portion and the supported portion.
Forming a single layer, and removing the sacrificial layer. A method for manufacturing an optical readout radiation-to-displacement converter, comprising: