JP4208846B2 - Uncooled infrared detector - Google Patents

Description

  The present invention relates to an uncooled infrared detection element.

  The non-cooling type (thermal type) infrared detection element is an element that absorbs infrared rays by an infrared absorption layer and converts the infrared rays into heat, and converts the heat into an electric signal by a thermoelectric conversion element. In the non-cooling type (thermal type) infrared detection element, a surface microstructure or bulk microstructure formation technique is utilized so that the infrared absorption layer and the thermoelectric conversion element are thermally isolated from the external system. Cooled infrared sensors are expensive and require a large cooler, whereas uncooled infrared elements have the advantage of being small and inexpensive.

  A conventional uncooled infrared detecting element is disclosed in, for example, Patent Document 1. The uncooled infrared detection element includes a substrate, a detection unit supported by a support leg on the substrate and provided with a detection film, and a first infrared absorption film (first umbrella structure unit) disposed substantially parallel to each other. And the second infrared absorption film (second umbrella structure), and the reflection that reflects the infrared light that has passed through the first infrared absorption film and the second infrared absorption film and enters the first infrared absorption film and the second infrared absorption film. The first optical distance between the first infrared absorption film and the reflection film and the second optical distance between the second infrared absorption film and the reflection film are different from each other.

In this uncooled infrared detection element, incident infrared rays are converted into heat by a two-stage umbrella structure, and a temperature rise is converted into an electrical signal by a detection film. At this time, the infrared rays that could not be absorbed by the umbrella structure portion are reflected by the reflection film (metal wiring layer) and are incident again on the umbrella structure portion, and the optical distance between the first infrared absorption film and the reflection film and the first (2) Absorption efficiency is increased by setting the optical distance between the infrared absorbing film and the reflecting film to m / 4 times the wavelength of infrared rays to be absorbed (m is an odd number).
JP 2003-294523 A

  However, in Patent Document 1, the reflection film is not formed on the entire detection surface. For example, there is an area without the reflection film around the support leg, and in such an area, a two-stage umbrella structure portion is provided. The infrared rays that have passed through the light will be lost. Since the area of the region without the reflection film reaches 30 to 40% of the entire detection surface, the infrared absorption efficiency is deteriorated and the sensitivity is lowered. Further, since the umbrella absorbing portion including the infrared absorbing film is formed in a double manner, the heat capacity of the infrared detecting element becomes very large and the response speed is lowered.

  An object of the present invention is to provide a highly sensitive uncooled infrared detection element capable of absorbing infrared rays over a wide area without reducing the response speed as much as possible.

  An uncooled infrared detection element according to a first embodiment of the present invention includes a semiconductor substrate having a cavity portion on a surface thereof, a wiring portion formed in a region surrounding the cavity portion of the semiconductor substrate, and the wiring portion Connected to the support portion disposed on the cavity portion of the semiconductor substrate inside the wiring portion, and supported on the cavity portion of the semiconductor substrate connected to the support portion and inside the support portion. A detection cell including a thermoelectric conversion unit, a first reflection layer, and a first absorption layer disposed in order, and covering a region other than the region of the first reflection layer on the detection cell and extending above the support unit. And a second absorption layer formed above the detection cell and the second reflection layer with a gap by a support column formed on the detection cell. It is characterized by that.

  An uncooled infrared detection element according to a second embodiment of the present invention includes a semiconductor substrate having a cavity portion provided on a surface thereof, a wiring portion formed in a region surrounding the cavity portion of the semiconductor substrate, and the wiring portion Connected to the support portion disposed on the cavity portion of the semiconductor substrate inside the wiring portion, and supported on the cavity portion of the semiconductor substrate connected to the support portion and inside the support portion. And a third reflection formed on the detection cell so as to cover a region other than the region of the first reflection layer, the thermoelectric conversion unit, the first reflection layer, and the first absorption layer arranged in order from A detection layer, a third reflection layer, and a fourth reflection layer formed on the wiring portion so as to protrude above the support portion; and a support column formed on the detection cell. The second reflection layer is formed above the fourth reflective layer with a gap therebetween. Characterized by comprising an absorbent layer.

An uncooled infrared detection element according to a third embodiment of the present invention includes a semiconductor substrate having a cavity formed on a surface thereof, a wiring part formed in a region surrounding the cavity of the semiconductor substrate, and the wiring part Connected to the support portion disposed on the cavity portion of the semiconductor substrate inside the wiring portion, and supported on the cavity portion of the semiconductor substrate connected to the support portion and inside the support portion. A detection cell including a thermoelectric conversion unit, a first reflection layer, and a first absorption layer disposed in order, and covering a region other than the region of the first reflection layer on the detection cell and extending above the support unit. The stacked body including the fifth reflective layer and the third absorbing layer formed so as to protrude and the support column formed on the detection cell are formed with a gap above the detection cell and the stacked body. and a second absorbent layer, said second absorbent And the first absorption layer, the optical distance between the first absorption layer and the first reflection layer, the optical distance between the second absorption layer and the third absorption layer, and The optical distances between the third absorption layer and the fifth reflection layer are different from each other .

  The uncooled infrared detection element in the embodiment of the present invention can absorb infrared rays in a wide area by improving the sensitivity by disposing a reflective layer in an area that could not be covered conventionally. In addition, the uncooled infrared detection element according to the embodiment of the present invention has a simpler structure and a smaller heat capacity than the conventional one, so that the response speed does not decrease.

  In the uncooled infrared detection element according to the first embodiment of the present invention, the second reflective layer is formed on the detection cell so as to cover a region other than the region of the first reflective layer and to protrude above the support portion, Only one second absorption layer is formed above the detection cell and the second reflection layer with a gap therebetween.

  In the uncooled infrared detection element according to the second embodiment of the present invention, the third reflective layer is formed on the detection cell so as to cover the region other than the region of the first reflective layer, and above the support portion on the wiring portion. A fourth reflective layer is formed so as to overhang, and only one second absorption layer is formed above the detection cell, the third reflective layer, and the fourth reflective layer with a gap therebetween.

  In the non-cooled infrared detection element according to the third embodiment of the present invention, the fifth reflective layer and the third absorption are so formed as to cover the region other than the region of the first reflective layer on the detection cell and project above the support portion. A laminated body including layers is formed, and only one second absorption layer is formed above the detection cell and the third absorption layer with a gap therebetween.

  As described above, the non-cooled infrared detecting element according to each embodiment of the present invention is almost entirely provided by disposing the reflective layer or the reflective layer and the absorbing layer above the region around the support portion that could not be covered conventionally. Infrared light can be absorbed in a wide area over the element area, and sensitivity can be improved. In addition, since the uncooled infrared detection element according to each embodiment of the present invention has only one second absorption layer having an umbrella structure, the structure is simpler and the heat capacity is smaller than that of the conventional one, leading to a decrease in response speed. There is nothing.

  In the uncooled infrared detection element according to the first embodiment, the optical distance between the second absorption layer and the first absorption layer, and the optical distance between the first absorption layer and the first reflection layer. It is preferable that optical distances between the second absorption layer and the second reflection layer are different from each other.

  In the uncooled infrared detection element according to the second embodiment, the optical distance between the second absorption layer and the first absorption layer, and the optical distance between the first absorption layer and the first reflection layer. It is preferable that the optical distance between the second absorption layer and the third reflection layer and the optical distance between the second absorption layer and the fourth reflection layer are different from each other.

  When these conditions are satisfied, infrared rays in a wide wavelength range can be absorbed, so that infrared absorption efficiency can be further increased.

  If a non-cooled infrared detection element according to an embodiment of the present invention is used to form a matrix of multiple columns and multiple rows, it can be used as an uncooled infrared imaging device.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings.

(First embodiment)
FIG. 1 is a cross-sectional view of an uncooled infrared detection element according to the first embodiment of the present invention, and FIG. 2 is a plan view of the lower side than the line BB in FIG.

  As shown in FIG. 1, a cavity 101 is provided on the surface of the silicon substrate 100. In a region surrounding the cavity 101 of the silicon substrate 100, a wiring portion 17 including a wiring layer 172 and an insulating layer 171 covering the periphery thereof is formed. A support portion 16 is connected to the wiring portion 17 so as to be disposed on the cavity portion 101 of the silicon substrate 100 inside the wiring portion 17. The support portion 16 includes a wiring layer 162 and an insulating layer 161 that covers the periphery thereof. The detection cell 11 is connected to the support portion 16 so as to be supported on the cavity portion 101 of the silicon substrate 100 inside the support portion 16. The detection cell 11 includes a thermoelectric conversion unit 111, an insulating layer 112 covering the periphery thereof, a first reflective layer 113, an insulating layer 191 covering the periphery thereof, and a first absorption layer 131 arranged in order from the bottom. The structure of the detection cell is simplified by using the wiring layer in the detection cell 11 as the first reflective layer 113. The first reflective layer (wiring layer) 113 is connected to the thermoelectric conversion unit 111 (the connection unit is not shown). On the detection cell 11, a second reflective layer 151 is formed so as to cover an area other than the area of the first reflective layer (wiring layer) 113 and to protrude above the support portion 16. Further, a support column 14 is formed on the detection cell 11, and the insulating layer 121 and the second absorption layer are supported by the support column 14 so as to form an umbrella structure with a gap above the detection cell 11 and the second reflection layer 151. 122 is formed. The second absorption layer 122 included in the umbrella structure is thermally connected to the detection cell 11 via the support column 14.

  The reason why the second reflective layer 151 has a step structure is as follows. That is, in a normal device, the upper end of the wiring portion 17 and the insulating layer 191 of the detection cell 11 are often set to the same height. Therefore, if the second reflective layer 151 is made flat without a step, the upper end of the wiring portion 17 is formed. As a result, the second reflective layer 151 comes into contact with the heat insulating property. However, if the wiring portion 17 is formed lower than the insulating layer 191, there is no need to provide a step in the second reflective layer 151 as shown in FIG.

  As shown in FIG. 2, the thermoelectric conversion unit 111 and the first reflective layer 113 are processed into a pattern including, for example, four rectangles. Further, the support portion 16 is formed in a pattern so as to form a pair of substantially key patterns, and the periphery of the support portion 16 is an etching hole 163. The wiring layer 162 of the support unit 16 has one end connected to the wiring layer 171 of the wiring unit 17 and the other end connected to the first reflective layer (wiring layer) 113 of the detection cell 11.

  The entire device is vacuum packaged, and the space between the umbrella structure (the insulating layer 121 and the second absorption layer 122) and the detection cell 11 and the cavity 101 is a vacuum layer. In this way, the detection cell 11 separated from the substrate 100 is placed in a vacuum to improve the heat insulation of the detection cell 11 and increase the sensitivity.

  If infrared rays are absorbed, the temperature of the detection cell 11 will rise and the electrical characteristics of the thermoelectric conversion part 111 will change. Changes in the electrical characteristics of the thermoelectric conversion unit 111 are read out via the first reflective layer (wiring layer) 113, the wiring layer 162 of the support unit 16, and the wiring layer 172 of the wiring unit 17.

  Here, as shown in FIG. 1, the element surface of the uncooled infrared detection element according to the present embodiment is divided into a first absorption region A1 and a second absorption region A2. The first absorption region A1 is a region where the second absorption layer 122, the first absorption layer 131, the first reflection layer 113, and the thermoelectric converter 111 are arranged in this order when viewed from the infrared incident side (upper side). The second absorption region A2 is a region where the second absorption layer 122 and the second reflection layer 151 are arranged in this order when viewed from the infrared incident side.

  In the first absorption region A <b> 1, a part of incident infrared rays is absorbed by the second absorption layer 122. Infrared light that has been transmitted without being absorbed by the second absorption layer 122 reaches the first absorption layer 131, and a part thereof is absorbed. Infrared light that is transmitted without being absorbed by the first absorption layer 131 reaches the first reflection layer (wiring layer) 113 and is reflected, reaches the first absorption layer 131 again, and a part thereof is absorbed. Further, the infrared rays that have been transmitted upward without being absorbed by the first absorption layer 131 among the reflected infrared rays return to the second absorption layer 122 and are absorbed. The first absorption region A1 corresponds to the region realized by the two-stage umbrella structure and the detection cell in the conventional element.

  In the second absorption region A2, a part of the incident infrared ray is absorbed by the second absorption layer 122. Infrared light that has been transmitted without being absorbed by the second absorption layer 122 reaches the second reflection layer 151 and is reflected, and returns to the second absorption layer 122 and is absorbed again. In the conventional element, there is a second absorption region A2 including the second reflective layer 151 (formed so as to cover a region other than the region of the first reflective layer 113 and to protrude above the support portion 16). There wasn't.

  As described above, in the uncooled infrared detection element according to the present embodiment, infrared rays are absorbed almost entirely including not only the first absorption region A1 but also the second absorption region A2, so the infrared absorption efficiency is improved and the sensitivity is improved. Further, since it is a simple structure in which only one stage of the umbrella structure is provided, the heat capacity is small and the response speed is not lowered.

  Next, a preferred design of the uncooled infrared detection element according to the present embodiment will be described with reference to FIG. As shown in FIG. 3, the physical distance between the second absorption layer 122 and the first absorption layer 131 in the first absorption region A1 is d1 (optical distance is L1), and the first absorption layer 131 and the first reflection layer. The physical distance between the second absorption region A2 and the second reflection layer 151 in the second absorption region A2 is d3 (the optical distance is L3). Here, the optical distance (also referred to as cavity thickness) is determined by the physical distance between the members and the refractive index of the insulating layer existing between the members. For example, when the refractive index of the insulating layer 191 existing between the first absorption layer 131 and the first reflection layer 113 is n, the optical distance L2 = nd2. As the insulating layer, silicon dioxide or a laminate of silicon dioxide and silicon nitride is used. Therefore, the optical distance can also be set by adjusting the film thickness ratio of silicon dioxide and silicon nitride contained in the laminate.

  In this embodiment, the wavelength of the infrared rays to be absorbed is λ (specifically, a range of 8 to 12 μm), and the optical distance is set to an integral multiple of λ / 4 (that is, 2 to 3 μm). Is preferred. The wavelengths of the infrared rays to be absorbed are set as λ1, λ2, and λ3, for example, L1 = λ1 / 4, L2 = λ2 / 4, and L3 = λ3 / 4. Further, L1 = λ1 / 2, L2 = λ2 / 4, and L3 = λ3 / 4 may be designed.

  Whether the second reflective layer 151 is provided with a step or not, it is possible to broaden the infrared absorption spectrum by planarly distributing a plurality of absorption cavities having different optical distances by the above-described design. it can. However, as shown in FIG. 1, it is advantageous to provide a step in the second reflective layer 151 in order to broaden the infrared absorption spectrum.

An example of the manufacturing method of the uncooled infrared detecting element according to the present embodiment will be described with reference to the steps (a) to (k) shown in FIGS.
(Step a) The silicon substrate 100 is prepared, and the detection cell 11, the support portion 16, and the wiring portion 17 are formed on the silicon substrate 100. The detection cell 11 includes a thermoelectric converter 111, an insulating layer 112 covering the periphery thereof, a first reflective layer 113 formed on the thermoelectric converter 111 via the insulating layer 112, and an insulating layer 191 covering the periphery thereof. Including. The thermoelectric converter 111 is made of a silicon pn junction diode, a bolometer material such as vanadium oxide (VOx), or the like. The support portion 16 includes a wiring layer 162 and an insulating layer 161 covering the periphery thereof. The wiring part 17 includes a wiring layer 172 and an insulating layer 171 covering the periphery thereof. At this time, an etching hole 163 is formed so as to form a pair of support portions 16 having a key-shaped pattern as shown in FIG. 2, and an upper portion of the support portion 16 is further etched.

(Step b) A first sacrificial layer 201 made of, for example, amorphous Si is deposited on the entire surface.
(Step c) A part of the first sacrificial layer 201 is etched so that the upper surface of the detection cell 11 is exposed.
(Step d) A lower protective layer 211, a first absorption layer 131, and a second reflection layer 151 are deposited on the entire surface. For example, TiN is used as the material of the first absorption layer 131. The second reflective layer 151 is etched so that the second reflective layer 151 is formed on the insulating layer 191 so as to overlap with the region other than the first reflective layer (wiring layer) 113 and on the first sacrificial layer 201 over the support portion 16. Leave. The first absorption layer 131 and the protective layer 211 at the upper center of the wiring layer 17 are etched to expose a part of the surface of the first sacrificial layer 201, and the pattern of the first absorption layer 131 is almost formed on the detection cell 11. It is formed so as to overlap with the pattern of the first reflective layer 113. Thereafter, an upper protective layer 211 is formed on the remaining second reflective layer 151 and first absorption layer 131.

(Step e) A second sacrificial layer 202 made of, for example, amorphous Si is deposited on the entire surface.
(Step f) Etching is performed until a part of the second sacrificial layer 202 on the detection cell 11 is penetrated to form an etching hole. At this time, the etching hole is formed on the detection cell 11 in a region where the first reflective layer (wiring layer) 113 is not present (second absorption region A2). This is because in the present embodiment, the first absorption region A1 has higher absorption efficiency than the second absorption region A2, and it is advantageous in terms of absorption efficiency to form the support column 14 in the second absorption region A2. It is.

  (Step g) Silicon dioxide is deposited, for example, to form the support layer 14 and the insulating layer 121 that is the lower layer of the umbrella structure.

  (Step h) If necessary, the insulating layer 121 is etched back to reduce the thickness. Next, a second absorption layer 122 made of, for example, TiN, and an insulating layer 121 that protects the second absorption layer 122 are deposited.

  (Step i) The insulating layer 121 and the second absorption layer 122 at the upper center of the wiring portion 17 are etched to expose the surface of the second sacrificial layer 202.

  (Step j) The second sacrificial layer 202 and the first sacrificial layer 201 are removed by etching, and a part of the silicon substrate 100 is etched to form the cavity 101. At this time, it is desirable to use an etchant (TMAH, KOH, etc.) having a large plane direction selection ratio of single crystal silicon.

  The uncooled infrared detection element according to the first embodiment can be manufactured through the above steps. In addition, the following steps are added as necessary.

  (Step k) The insulating layer 121, the support column 14, and the protective layer 211 are etched using, for example, hydrofluoric acid. By this step, the thickness of the insulating layer 122 and the thickness of the support column 14 can be adjusted, and the reflectance of the second reflective layer 151 can be improved.

(Second Embodiment)
FIG. 9 is a cross-sectional view of an uncooled infrared detection element according to the second embodiment of the present invention, and FIG. 10 is a plan view of the area below the line BB in FIG.

  As shown in FIG. 9, the uncooled infrared detection element according to the present embodiment has a region other than the region of the first reflective layer 111 on the detection cell 11 instead of the second reflective layer 151 in the first embodiment. It has a structure in which a third reflective layer 153 formed so as to cover and a fourth reflective layer 154 formed so as to protrude above the support portion 16 on the wiring portion 17 is provided. In order to realize such a structure, the height of the wiring portion 17 is set higher than the height of the detection cell 11.

  The element surface of the uncooled infrared detection element according to the present embodiment will be divided into a first absorption region A1, a third absorption region A3, and a fourth absorption region A4. The first absorption region A1 is a region where the second absorption layer 122, the first absorption layer 131, the first reflection layer 113, and the thermoelectric converter 111 are arranged in this order when viewed from the infrared incident side (upper side). The third absorption region A3 is a region where the second absorption layer 122 and the third reflection layer 153 are arranged in this order when viewed from the infrared incident side. The fourth absorption region A4 is a region where the second absorption layer 122 and the fourth reflection layer 154 are arranged in this order when viewed from the infrared light incident side.

  Even in the non-cooled infrared detecting element according to the present embodiment, infrared rays are absorbed not only in the first absorption region A1 but also in almost the entire surface including the third absorption region A3 and the fourth absorption region A4. Sensitivity can be improved. Further, in the present embodiment, unlike the first embodiment, since the fourth reflective layer 154 is not formed on the detection cell 11, a further reduction in heat capacity can be expected as compared with the first embodiment.

  With reference to FIG. 11, a preferred design of the uncooled infrared detection element according to the present embodiment will be described. As shown in FIG. 11, the physical distance between the second absorption layer 122 and the first absorption layer 131 in the first absorption region A1 is d1 (optical distance is L1), and the first absorption layer 131 and the first reflection layer. 113 is d2 (optical distance is L2), the physical distance between the second absorption layer 122 and the third reflective layer 153 in the third absorption region A3 is d4 (optical distance is L4), and fourth. The physical distance between the second absorption layer 122 and the fourth reflection layer 154 in the absorption region A4 is d5 (optical distance is L5).

  In the present embodiment, the wavelengths of infrared rays to be absorbed are λ1, λ2, λ4, and λ5 so that, for example, L1 = λ1 / 4, L2 = λ2 / 4, L4 = λ4 / 4, and L5 = λ5 / 4. To design. Further, L1 = λ1 / 4, L2 = λ2 / 2, L4 = λ4 / 4, and L5 = λ5 / 4 may be designed. By designing in this way, broadband infrared rays can be absorbed.

  Of the method for manufacturing an uncooled infrared detection element according to this embodiment, steps different from those of the first embodiment will be described. In the present embodiment, the step (d) (FIG. 5) in the first embodiment is changed as shown in FIG. The first sacrificial layer 201 is etched so that the upper surface of the detection cell 11 and the upper surface of the wiring part 17 are exposed. Next, a lower protective film 211 and a first absorption layer 131 are deposited. Next, after depositing a metal layer, patterning is performed to form the third reflective layer 153 at the edge of the detection cell 11 and the fourth reflective layer 154 on the wiring portion 17. Thereafter, if necessary, a part of the first absorption layer 131 and the protective film 211 is etched to expose the surface of the first sacrificial layer 201. Next, an upper protective layer 211 is deposited. After this step, the same process as the method for manufacturing the uncooled infrared detection element according to the first embodiment can be adopted to manufacture the uncooled infrared detection element according to the present embodiment.

(Third embodiment)
FIG. 13 is a cross-sectional view of an uncooled infrared detection element according to the third embodiment of the present invention, and FIG. 14 is a plan view seen below the line BB in FIG.

  As shown in FIG. 9, the uncooled infrared detection element according to the present embodiment is formed on the detection cell 11 so as to cover a region other than the region of the first reflective layer 113 and to protrude above the support portion 16. The insulating layer 192 and the third absorbing layer 133 are provided on the fifth reflective layer 155 (corresponding to the second reflective layer 151 in the first embodiment).

  When the element surface of the uncooled infrared detection element according to the present embodiment is divided into the first absorption area A1 and the fifth absorption area A5, the first absorption area A1 and the second absorption area A2 in the first embodiment The plan view is substantially the same as FIG.

  Therefore, even in the uncooled infrared detecting element according to the present embodiment, the infrared ray is absorbed almost on the entire surface, so that the infrared absorption efficiency can be improved and the sensitivity can be improved, and the simple structure in which only one stage of the umbrella structure is provided. Therefore, the heat capacity is small and the response speed is not lowered.

  With reference to FIG. 14, the suitable design of the uncooled infrared rays detection element which concerns on this embodiment is demonstrated. As shown in FIG. 14, the physical distance between the second absorption layer 122 and the first absorption layer 131 in the first absorption region A1 is d1 (optical distance is L1), and the first absorption layer 131 and the first reflection layer. 113 is d2 (optical distance is L2), the physical distance between the second absorption layer 122 and the third absorption layer 133 in the fifth absorption region A5 is d6 (optical distance is L6), and third The physical distance between the absorption layer 133 and the fifth reflective layer 155 is d7 (optical distance is L7).

  In the present embodiment, the wavelengths of infrared rays to be absorbed are λ1, λ2, λ6, and λ7 so that, for example, L1 = λ1 / 4, L2 = λ2 / 4, L6 = λ6 / 4, and L7 = λ7 / 4. To design. Further, it may be designed such that L1 = λ1 / 4, L2 = λ2 / 2, L6 = λ6 / 4, and L7 = λ7 / 2. By designing in this way, broadband infrared rays can be absorbed.

  Of the method for manufacturing an uncooled infrared detection element according to this embodiment, steps different from those of the first embodiment will be described. In the present embodiment, the step (d) (FIG. 5) in the first embodiment is changed as shown in FIG. The first sacrificial layer 201 is etched so that the upper surface of the detection cell 11 is exposed. Next, the lower protective film 211, the first absorption layer 131, the fifth reflection layer 155, the insulating layer 192, and the third absorption layer 132 are deposited. Next, the third absorbing layer 132, the insulating layer 192, and the fifth reflecting layer 155 at the upper part of the first reflecting layer 113 and at the upper center of the wiring part 17 are etched. Next, the surface of the first sacrificial layer is exposed by etching the first absorption layer 131 at the upper center of the wiring part 17 and the insulating film 211 at the lower part. Further, an upper protective layer 211 is deposited. From this step onward, the same process as the method for manufacturing the uncooled infrared detection element according to the first embodiment can be employed to manufacture the uncooled infrared detection element according to the present embodiment.

FIG. 3 is a cross-sectional view of the uncooled infrared detection element according to the first embodiment. FIG. 3 is a plan view of the uncooled infrared detection element according to the first embodiment. FIG. 3 is a diagram for explaining an optical distance in the uncooled infrared detection element according to the first embodiment. Sectional drawing which shows the manufacturing method of the uncooled infrared rays detection element which concerns on Embodiment 1. FIG. Sectional drawing which shows the manufacturing method of the uncooled infrared rays detection element which concerns on Embodiment 1. FIG. Sectional drawing which shows the manufacturing method of the uncooled infrared rays detection element which concerns on Embodiment 1. FIG. Sectional drawing which shows the manufacturing method of the uncooled infrared rays detection element which concerns on Embodiment 1. FIG. Sectional drawing which shows the manufacturing method of the uncooled infrared rays detection element which concerns on Embodiment 1. FIG. Sectional drawing of the uncooled infrared rays detection element which concerns on Embodiment 2. FIG. FIG. 6 is a plan view of an uncooled infrared detection element according to the second embodiment. The figure explaining the optical distance in the uncooled infrared rays detection element which concerns on Embodiment 2. FIG. Sectional drawing which shows the manufacturing method of the uncooled infrared rays detection element which concerns on Embodiment 2. FIG. Sectional drawing of the uncooled infrared rays detection element which concerns on Embodiment 3. FIG. The figure explaining the optical distance in the uncooled infrared rays detection element which concerns on Embodiment 3. FIG. Sectional drawing which shows the manufacturing method of the uncooled infrared rays detection element which concerns on Embodiment 3. FIG.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 100 ... Silicon substrate, 101 ... Cavity part, 11 ... Detection cell, 111 ... Thermoelectric conversion part, 112 ... Insulating layer, 113 ... 1st reflection layer, 121 ... Insulating layer, 122 ... 2nd absorption layer, 131 ... 1st absorption Layer, 133 ... third absorbing layer, 14 ... support, 151 ... second reflecting layer, 153 ... third reflecting layer, 154 ... fourth reflecting layer, 155 ... fifth reflecting layer, 16 ... supporting part, 161 ... insulating layer , 162 ... wiring layer, 163 ... etching hole, 17 ... wiring part, 171 ... insulating layer, 172 ... wiring layer, 191, 192 ... insulating layer, 201 ... first sacrificial layer, 202 ... second sacrificial layer, 211 ... insulating layer.

Claims (5)

A semiconductor substrate having a cavity on the surface;
A wiring portion formed in a region surrounding the cavity of the semiconductor substrate;
A support portion connected to the wiring portion and disposed on the cavity of the semiconductor substrate inside the wiring portion;
A detection cell connected to the support part and supported on the cavity of the semiconductor substrate inside the support part and arranged in order from the bottom; a detection cell including a first reflective layer and a first absorption layer;
A second reflective layer formed on the detection cell so as to cover an area other than the area of the first reflective layer and to protrude above the support;
An uncooled infrared detection element, comprising: a support formed on the detection cell; and a second absorption layer formed above the detection cell and the second reflective layer with a gap therebetween. A semiconductor substrate having a cavity on the surface;
A wiring portion formed in a region surrounding the cavity of the semiconductor substrate;
A support portion connected to the wiring portion and disposed on the cavity of the semiconductor substrate inside the wiring portion;
A detection cell connected to the support part and supported on the cavity of the semiconductor substrate inside the support part and arranged in order from the bottom; a detection cell including a first reflective layer and a first absorption layer;
A third reflective layer formed on the detection cell so as to cover a region other than the region of the first reflective layer;
A fourth reflective layer formed on the wiring part so as to protrude above the support part;
And a second absorption layer formed above the detection cell, the third reflective layer, and the fourth reflective layer by a support formed on the detection cell with a gap therebetween. Cooling infrared detector. A semiconductor substrate having a cavity on the surface;
A wiring portion formed in a region surrounding the cavity of the semiconductor substrate;
A support portion connected to the wiring portion and disposed on the cavity of the semiconductor substrate inside the wiring portion;
A detection cell connected to the support part and supported on the cavity of the semiconductor substrate inside the support part and arranged in order from the bottom; a detection cell including a first reflective layer and a first absorption layer;
A laminate including a fifth reflective layer and a third absorption layer formed on the detection cell so as to cover a region other than the region of the first reflective layer and to protrude above the support portion;
The support column formed on the detection cell comprises a second absorption layer formed above the detection cell and the stacked body with a gap therebetween, and the second absorption layer and the first absorption layer An optical distance between the first absorption layer and the first reflection layer, an optical distance between the second absorption layer and the third absorption layer, and the third absorption layer and the first 5. An uncooled infrared detecting element , wherein optical distances between the reflecting layers are different from each other .   An optical distance between the second absorbing layer and the first absorbing layer, an optical distance between the first absorbing layer and the first reflecting layer, and between the second absorbing layer and the second reflecting layer. The uncooled infrared detection element according to claim 1, wherein optical distances between them are different from each other.   An optical distance between the second absorbing layer and the first absorbing layer, an optical distance between the first absorbing layer and the first reflecting layer, and between the second absorbing layer and the third reflecting layer. The optical distance between the second absorption layer and the fourth reflection layer is different from each other, and the uncooled infrared detection element according to claim 2.

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