WO2018042708A1 - Thermoelectric conversion device and electronic device - Google Patents

Abstract

This thermoelectric conversion device is provided with: first thermoelectric thin films 12a and second thermoelectric thin films 12b, which are alternately provided in the first direction that is parallel to the surfaces of the first thermoelectric thin films and those of the second thermoelectric thin films, and which respectively have conductivity types different from each other; first connection layers 14a and second connection layers 14b, which are, among the first thermoelectric thin films and the second thermoelectric thin films, electrically and thermally connected to the first thermoelectric thin films and the second thermoelectric thin films, and which are alternately provided in the first direction; and first thermally conductive layers 16a and second thermally conductive layers 16b, which are thermally connected to the first connection layers and the second connection layers, respectively, and which extend in the second direction orthogonal to the surfaces.

Description

Thermoelectric conversion device and electronic device

The present invention relates to a thermoelectric conversion device and an electronic device, for example, a thermoelectric conversion device and an electronic device having a thermoelectric thin film.

A thermoelectric generator (or thermoelectric generator) called a thermoelectric generator (TEG) that integrates a large number of Seebeck elements made of thermoelectric materials is used to generate power using exhaust heat from power plants, factories, and automobiles. Expected as a technology. Recently, a small thermoelectric conversion device called a micro thermoelectric generation module (μTEG: Micro Thermoelectric Generator) is expected as an energy harvesting element that can be used for wearable devices and sensor nodes. Further, in such a μTEG, power generation using exhaust heat from a microprocessor or a system-on-chip (SoC) can be considered.

By forming a large number of n-type and p-type thermoelectric materials processed into columnar shapes on the lower surface of the upper substrate and the upper surface of the lower substrate, respectively, and bonding the upper substrate and the lower substrate , ΜTEG is known (for example, Patent Document 1). In this structure, the direction of heat flow and current in the thermoelectric layer is the normal direction of the substrate. Since this type of μTEG has a structure in which a large number of π-type Seebeck elements are connected, it is hereinafter referred to as π-type.

A structure is described in which n-type and p-type strip-shaped thermoelectric thin films are alternately arranged in the width direction of the strips, and the ends of the thermoelectric thin films are alternately connected. In this structure, the direction of heat flow and current in the thermoelectric thin film is the length direction of the strip. This type of μTEG is hereinafter referred to as an in-plane type.

US Pat. No. 7,402,910

By using a thin-film thermoelectric material, the thermoelectric conversion device can be miniaturized and highly integrated. However, when a thin thermoelectric material is used for π-type or in-plane μTEG, the thermal resistance and the electrical resistance are in a trade-off relationship, and it is difficult to realize a high-power thermoelectric conversion device.

The present invention has been made in view of the above problems, and an object thereof is to provide a small-sized and high-output thermoelectric conversion device and electronic device.

The present invention provides the first thermoelectric thin film and the second thermoelectric thin film having opposite conductivity types alternately provided in a first direction parallel to the surfaces of the first thermoelectric thin film and the second thermoelectric thin film, and the first thermoelectric thin film, Between the thermoelectric thin film and the second thermoelectric thin film, the first thermoelectric thin film and the second thermoelectric thin film are electrically and thermally connected, and the first connection layer and the second are alternately provided in the first direction. A connection layer; and a first heat conduction layer and a second heat conduction layer that are thermally connected to the first connection layer and the second connection layer, respectively, and extend in a second direction intersecting the surface. Is a thermoelectric conversion device characterized by

In the above configuration, the first thermoelectric thin film and the second thermoelectric thin film may have a thickness of 10 μm or less.

In the above configuration, the first heat conductive layer and the second heat conductive layer may be provided on opposite sides of the surfaces of the first thermoelectric thin film and the second thermoelectric thin film.

The said structure WHEREIN: The said 1st heat conductive layer and the said 2nd heat conductive layer can be set as the structure which comprises the insulator whose heat conductivity is smaller than the said 1st heat conductive layer and the said 2nd heat conductive layer. .

In the above configuration, the first thermoelectric thin film and the second thermoelectric thin film extend in a third direction parallel to the surface and intersecting the first direction, and the first thermoelectric thin film and the second thermoelectric thin film The length in the third direction may be 10 times or more the film thickness of the first thermoelectric thin film and the second thermoelectric thin film.

In the above configuration, the width of the first thermoelectric thin film and the second thermoelectric thin film in the first direction may be larger than the thickness of the first thermoelectric thin film and the second thermoelectric thin film.

In the above configuration, a first base and a second base that are thermally connected to the first heat conductive layer and the second heat conductive layer, respectively, may be provided.

In the above-described configuration, the first heat conductive layer penetrates through the solid first insulator having a lower thermal conductivity than the first heat conductive layer, and the second heat conductive layer penetrates through the second heat conductive layer. A solid second insulator having low conductivity; and a first base and a second base that are thermally connected to the first heat conductive layer and the second heat conductive layer, respectively, and the first base and The first insulator has a first groove between the first heat conductive layers, and the second base and the second insulator have a second groove between the second heat conductive layers. It can be.

In the above configuration, the layer including the first thermoelectric thin film, the second thermoelectric thin film, the first connection layer, the second connection layer, the first heat conduction layer, and the second heat conduction layer intersects the surface. A plurality of layers are stacked in a direction, and the first heat conductive layer included in one of the adjacent layers among the plurality of layers and the second heat conductive layer included in the other of the adjacent layers are thermally connected. It can be set as a structure.

In the above configuration, the first base is thermally connected to the surface of the living body of the thermostat animal, the second base is thermally connected to the air, and is provided between the first base and the second base. The first thermoelectric thin film, the second thermoelectric thin film, the first connection layer, the second connection layer, the first heat conduction layer, and the second heat conduction layer, the first heat conduction layer and the first heat conduction layer. The two heat conductive layers are each provided between the first base and the second base, and between the first base and the second base and outside the thermoelectric conversion unit. And a thermal insulator having a thermal conductivity smaller than that of the first thermoelectric thin film, the second thermoelectric thin film, the first base portion, and the second base portion.

The present invention is provided between a first base that is thermally connected to the surface of a living body of a thermostat animal, a second base that is thermally connected to air, and the first base and the second base. The first thermoelectric material provided between the first connection layer and the second connection layer and the second thermoelectric material having a conductivity type opposite to that of the first thermoelectric material are the first connection layer and the second connection layer. A thermoelectric conversion unit connected in series alternately via a connection layer, wherein the first connection part and the second connection part are thermally connected to the first base part and the second base part, respectively; Heat that is between the base and the second base and provided outside the thermoelectric conversion unit and that is smaller than the thermal conductivity of the first thermoelectric material, the second thermoelectric material, the first base, and the second base. A thermoelectric conversion device comprising a thermal insulator having conductivity.

In the above configuration, the thermal insulator may be a solid layer.

In the above configuration, the thermal insulator may be a gas layer or vacuum having a pressure lower than atmospheric pressure, and the thermoelectric conversion device may include a holding unit that holds the gas layer or vacuum.

In the above-described configuration, a plurality of the thermoelectric conversion units separated from each other via the thermal insulator may be provided between the first base and the second base.

The present invention includes an integrated circuit element, a heat radiating member that radiates heat generated in the integrated circuit element, and the thermoelectric conversion device, and is provided between the integrated circuit element and the heat radiating member, and the first heat And a power generating device in which a conductive layer is thermally connected to the integrated circuit element and the second heat conductive layer is connected to the heat dissipation member.

The present invention provides an integrated circuit element, a heat radiating member that radiates heat generated in the integrated circuit element, a first thermoelectric material provided between a first connection layer and a second connection layer, and the first thermoelectric material. A thermoelectric conversion device in which a second thermoelectric material having a conductivity type opposite to that of the thermoelectric conversion device is alternately connected in series via the first connection layer and the second connection layer, and the integrated circuit element and the heat dissipation member And a power generation device in which the first connection layer is thermally connected to the integrated circuit element and the second connection layer is connected to the heat dissipation member. Device.

In the above configuration, a power storage device that stores the power generated by the power generation device and supplies the power to the integrated circuit element can be provided.

The present invention provides a first base and a second base, the first thermoelectric thin film and the second thermoelectric thin film arranged in the surface direction of the first base and the second base and having opposite conductivity types, A first connection in which the first thermoelectric thin film and the second thermoelectric thin film are alternately and thermally connected in a direction intersecting the plane direction, and thermally connected to the first base and the second base, respectively. And a second connection layer, wherein the size of the first thermoelectric thin film and the second thermoelectric thin film in the surface direction is 1 μm or less.

According to the present invention, a small and high output thermoelectric conversion device and electronic device can be provided.

FIG. 1 is a schematic diagram showing a Seebeck element. FIG. 2A and FIG. 2B are a plan view and a cross-sectional view, respectively, of the thermoelectric conversion device according to Comparative Example 1. FIG. 3A and FIG. 3B are a plan view and a cross-sectional view, respectively, of the thermoelectric conversion device according to Comparative Example 2. FIG. 4A and FIG. 4B are a plan view and a cross-sectional view, respectively, of the thermoelectric conversion device according to the first embodiment. FIG. 5A to FIG. 5C are diagrams showing simulation results of m ₀ , γd and P _OUT for γ in Comparative Example 1, respectively. FIGS. 6 (a) and 6 (b), _P OUT, _{m 0} for _{t 0} in Comparative Example 1, .gamma.d, a diagram illustrating a simulation result of (1-γ) d and _{t Cu.} FIG. 7 is a diagram illustrating simulation results of P _OUT , m ₀ , γd, (1-γ) d, and t _Cu with respect to V _S in Comparative Example 1. FIG. 8A to FIG. 8C are diagrams illustrating simulation results of m ₀ , γd, and P _OUT for γ in Example 1, respectively. FIG. 9 is a diagram illustrating simulation results of P _OUT , m ₀ , γd, (1-γ) d, and t _Cu with respect to t ₀ in Example 1. FIG. 10 is a diagram illustrating the P _OUT , m ₀ , γd, (1-γ) d and t _Cu simulation results for V _S in Example 1. FIG. 11A and FIG. 11B are cross-sectional views of the thermoelectric conversion device according to the first modification of the first embodiment. FIG. 12 is a plan view of the thermoelectric conversion device according to the second modification of the first embodiment. FIG. 13A and FIG. 13B are a cross-sectional view and a plan view of the thermoelectric conversion device according to the third modification of the first embodiment. 14A and 14B are cross-sectional views of the thermoelectric conversion device according to the fourth modification of the first embodiment, and FIG. 14C is a thermoelectric conversion device according to the fifth modification of the first embodiment. FIG. FIG. 15A and FIG. 15B are cross-sectional views of an electronic device using the thermoelectric conversion device according to the sixth modification of the first embodiment. FIG. 16 is a cross-sectional view of the electronic device according to the second embodiment. FIG. 17 is a block diagram of an electronic device according to the first modification of the second embodiment. FIG. 18 is a block diagram of a power system according to a first modification of the second embodiment. FIG. 19A and FIG. 19B are diagrams showing a simulation model. 20A and 20B are diagrams showing simulation results of γd, (1-γ) d, ΔT, βΔT, V _S and P _OUT for γ and m ₀ in Example 1, respectively. FIG. 21 is a diagram illustrating simulation results of γd, (1−γ) d, ΔT, βΔT, V _S and P _OUT with respect to t ₀ in Example 1. FIG. 22 is a diagram illustrating simulation results of γd, (1-γ) d, ΔT, βΔT, V _S and P _OUT with respect to t ₀ in Comparative Example 1. FIG. 23A and FIG. 23B are schematic cross-sectional views of thermoelectric conversion devices according to Comparative Example 1 and Example 1, respectively. FIG. 24 is a diagram illustrating the current I and the output power P _OUT with respect to the output voltage V _{out in the} first embodiment. FIG. 25 is a diagram showing simulation results of γd, (1-γ) d, ΔT, βΔT, V _S and P _OUT with respect to the minimum dimension in Comparative Example 1. FIG. 26A is a plan view of the thermoelectric conversion device according to the fourth embodiment, and FIG. 26B is a cross-sectional view taken along the line AA in FIG. FIG. 27 is a diagram illustrating simulation results of γd, (1-γ) d, ΔT, βΔT, V _S and P _OUT with respect to D in Example 4. FIG. 28A is a plan view of a thermoelectric conversion device according to Modification 1 of Embodiment 4, and FIG. 28B is a cross-sectional view taken along line AA of FIG. FIG. 29A is a diagram showing a simulation result of t _Cu , γd, m ₀ , V _S and P _OUT with respect to L in Modification 1 of Example 4, and FIG. 29B is a diagram showing L, γd with respect to t _Cu . , M ₀ , V _S and P _OUT are diagrams illustrating simulation results. FIG. 30 is a diagram showing simulation results of L, γd, m ₀ , V _S and P _OUT with respect to t _Cu when the thermal insulator is vacuum. FIG. 31 is a cross-sectional view of the thermoelectric conversion device according to the second modification of the fourth embodiment. FIG. 32A is a plan view of a thermoelectric conversion device according to a third modification of the fourth embodiment, and FIG. 32B is a cross-sectional view taken along the line AA in FIG. FIG. 33A is a plan view of a thermoelectric conversion device according to a fourth modification of the fourth embodiment, and FIG. 33B is a cross-sectional view taken along the line AA in FIG.

FIG. 1 is a schematic diagram showing a Seebeck element. As shown in FIG. 1, the Seebeck element 10 includes thermoelectric materials 32a and 32b, electrodes 24a and 24b, and a connection layer 34a. The thermoelectric materials 32a and 32b are, for example, n-type and p-type, respectively. One ends of the thermoelectric materials 32a and 32b are connected via a connection layer 34a. The other ends of the thermoelectric materials 32a and 32b are connected to electrodes 24a and 24b, respectively. When the connection layer 34a absorbs heat as indicated by an arrow 36a and radiates heat from the electrodes 24a and 24b as indicated by an arrow 36b, an electromotive force is generated between the electrodes 24a and 24b due to the Seebeck effect. When a load 40 is connected between the electrodes 24a and 24b, a current 42 flows. The electromotive force can be increased by connecting a plurality of such Seebeck elements 10 in series.

The thermoelectric conversion device (or thermoelectric power generation device) is manufactured by joining a number of pellets of n-type thermoelectric material and p-type thermoelectric material cut by, for example, machining. In addition, the thermoelectric conversion device can be manufactured by attaching a substrate on which a p-type thermoelectric material is formed in a number of pellets to a substrate on which a n-type thermoelectric material is formed in a number of pellets. In these manufacturing methods, it is difficult to increase the degree of integration of Seebeck elements, and the degree of integration of Seebeck elements is, for example, about several hundred.

Since the electromotive force per Seebeck element is small, it is preferable to use a plurality of Seebeck elements connected in series. However, if the integration degree of Seebeck elements is small, the number of Seebeck elements connected in series is limited. For this reason, when trying to increase the output power of the thermoelectric conversion device, the thermoelectric conversion device is designed with priority given to the electromotive force per Seebeck element. In general, such a design that gives priority to electromotive force per unit does not have a structure optimized for output power.

Therefore, it is conceivable to produce a thermoelectric conversion device by applying a microfabrication technique and a thin film formation technique based on a photolithography technique used for production of a semiconductor integrated circuit or the like. In such a method, it is possible to design a thermoelectric conversion device having desired output characteristics from the number of Seebeck elements to be integrated and the degree of freedom of the element shape and dimensions. As a result, there is a possibility that a thermoelectric conversion device in which Seebeck elements having an optimized structure are integrated at a high density and on a large scale may be realized.

[Comparative Example 1]
The structure of a thermoelectric converter using a thin film as the thermoelectric material was investigated. Comparative Example 1 is an example using a π-type Seebeck element. FIG. 2A and FIG. 2B are a plan view and a cross-sectional view, respectively, of the thermoelectric conversion device according to Comparative Example 1. In FIG. 2A, the thermoelectric thin film, the connection layer, and the electrode are illustrated. FIG. 2B is a cross-sectional view taken along the line AA in FIG. The arrangement direction of the thermoelectric thin films 12a and 12b is the X direction and the Y direction, and the lamination method of each layer is the Z direction.

As shown in FIGS. 2A and 2B, in the thermoelectric converter 110, the thermoelectric thin films 12a and the thermoelectric thin films 12b are alternately arranged in the X direction. The thermoelectric thin films 12a and 12b are, for example, n-type and p-type, respectively. Adjacent thermoelectric thin films 12a and 12b are electrically and thermally connected to connection layers 14a and 14b in the -Z direction and the + Z direction, respectively. One Seebeck element 10 is formed by a pair of thermoelectric thin films 12a and 12b. The plurality of Seebeck elements 10 are connected in series between the electrodes 24a and 24b. The connection layer 14a is thermally connected to the high temperature base portion 22a via the electrical insulating film 20 in the -Z direction. The connection layer 14b is thermally connected to the low temperature base portion 22b via the electrical insulating film 20 in the + Z direction. An electrical and thermal insulating layer 18 is provided between the thermoelectric thin films 12a and 12b.

The dimensions of the base portions 22a and 22b in the X direction and the Y direction are D, the length of one side of the square 26 including the one thermoelectric thin film 12a or 12b is d, and the dimension of one side of the thermoelectric thin film 12a or 12b in the square 26 Is the element size γd. Of the voltage difference between the electrodes 24a and 24b, the electromotive force V _S by the Seebeck element 10, the temperature difference between the surfaces of the base portions 22a and 22b is ΔT, the film thicknesses of the thermoelectric thin films 12a and 12b are t ₀ , the connection layer 14a and the thickness of 14b _{t Cu,} the thickness of the insulating film 20 _{t Al2 O3,} the thickness of the base portion 22a and 22b and _{t HS.}

In Comparative Example 1, heat conduction occurs in the Z direction. Therefore, the thickness _{t 0} of the thermoelectric film 12a and 12b is reduced (e.g. 100 nm), heat resistance is reduced, the temperature difference [Delta] T _G in the Z direction of the thermoelectric film 12a and 12b (not shown) is reduced. For this reason, an electromotive force will fall. An attempt to obtain sufficient heat resistance, will be the X-direction and Y dimensions of the thermoelectric film 12a and 12b and the thickness of about t _0, the processing process is not realistic not easy.

[Comparative Example 2]
Comparative Example 2 is an example using an in-plane type Seebeck element. FIG. 3A and FIG. 3B are a plan view and a cross-sectional view, respectively, of the thermoelectric conversion device according to Comparative Example 2. FIG. 3A shows the thermoelectric thin film, the connection layer, and the base. FIG. 3B is a cross-sectional view taken along the line AA in FIG. The arrangement direction and the stretching direction of the thermoelectric thin films 12a and 12b are the X direction and the Y direction, respectively, and the lamination method of each layer is the Z direction.

3 (a) and 3 (b), in the thermoelectric conversion device 112, the thermoelectric thin films 12a and the thermoelectric thin films 12b are alternately arranged in the X direction and extend in the Y direction. The thermoelectric thin films 12a and 12b are, for example, n-type and p-type, respectively. Adjacent thermoelectric thin films 12a and 12b are electrically and thermally connected to connection layers 14a and 14b in the -Y direction and the + Y direction, respectively. One Seebeck element 10 is formed by a pair of thermoelectric thin films 12a and 12b. The plurality of Seebeck elements 10 are connected in series between the electrodes 24a and 24b. The connection layer 14a is thermally connected to the high temperature base portion 22a in the -Y direction. The connection layer 14b is thermally connected to the low temperature base 22b in the + Y direction. An insulating layer 18 is provided between the thermoelectric thin films 12a and 12b.

In Comparative Example 2, the length L in the Y direction in which heat conduction of the thermoelectric thin films 12a and 12b occurs can be increased. Thereby, temperature difference (DELTA) _TG (not shown) of the Y direction of the thermoelectric thin films 12a and 12b can be enlarged. However, as the length L increases, the electrical resistance of the thermoelectric thin films 12a and 12b increases. Thereby, even if the electromotive force V _S can be increased, the output power cannot be increased.

As described above, in the π-type comparative example 1 using the thermoelectric thin films 12a and 12b, the thermal resistance is too low, and in the in-plane type comparative example 2, the electric resistance is too high. Thus, Comparative Examples 1 and 2 do not have a structure suitable for optimizing the thermal resistance and electrical resistance in a trade-off relationship and realizing high output power.

FIGS. 4A and 4B are a plan view and a cross-sectional view, respectively, of the thermoelectric conversion device according to the first embodiment. FIG. 4A illustrates a thermoelectric thin film, a connection layer, and electrodes. FIG. 4B is a cross-sectional view taken along the line AA in FIG. The surface of the thermoelectric thin films 12a and 12b is the XY plane, the arrangement direction (width direction) and the stretching direction (length direction) of the thermoelectric thin films 12a and 12b are the X direction and the Y direction, respectively, and the lamination method of each layer is the Z direction. .

As shown in FIGS. 4A and 4B, in the thermoelectric conversion device 100, the thermoelectric thin film 12a and the thermoelectric thin film 12b have a strip shape in plan view. The thermoelectric thin films 12a and 12b are alternately arranged in the X direction and extend in the Y direction. The thermoelectric thin films 12a and 12b are, for example, n-type and p-type, respectively. Adjacent thermoelectric thin films 12a and 12b are electrically and thermally connected to connection layers 14a and 14b alternately in the X direction. The connection layers 14a and 14b extend in the Y direction. One Seebeck element 10 is formed by a pair of thermoelectric thin films 12a and 12b. The plurality of Seebeck elements 10 are connected in series between the electrodes 24a and 24b. Connection layers 14a and 14b are thermally connected to heat conductive layers 16a and 16b in the −Z direction and the + Z direction, respectively. The heat conductive layers 16a and 16b are thermally connected to the high temperature base portion 22a and the low temperature base portion 22b through the electrical insulating film 20, respectively. Insulating layers 18a and 18b are provided between heat conductive layers 16a and 16b.

The dimension of the thermoelectric conversion device 100 in the X direction and the Y direction is D, the pitch of the thermoelectric thin films 12a and 12b in the X direction is d, and the dimension of one thermoelectric thin film 12a or 12b is the element dimension γd. Of the voltage difference between the electrodes 24a and 24b, the electromotive force V _S by the Seebeck element 10 and the temperature difference between the surfaces of the base portions 22a and 22b are ΔT. The film thickness of the thermoelectric thin films 12a and 12b and the connection layers 14a and 14b is t ₀ , the film thickness of the heat conductive layers 16a and 16b is t _Cu , the film thickness of the insulating film 20 is t _Al2O3 , and the film thickness of the base portions 22a and 22b is t _Let it be _HS .

In such a structure, the heat flow and current directions of the thermoelectric thin films 12a and 12b are in the X direction. In Comparative Example 1, the film thickness t ₀ of the thermoelectric film 12a and 12b is reduced, the thermal resistance is reduced, in Example 1, the thermal resistance when the film thickness t ₀ becomes smaller increases. In Comparative Example 2, the electrical resistance increased as the length L in the Y direction of the thermoelectric thin films 12a and 12b increased. However, in Example 1, the electrical resistance decreased as the length L increased. Thus, by sufficiently larger than the length L to thickness t _0, the thermal resistance is not too small, and without electrical resistance is too large, a trade-off using the X-direction of the element dimensions .gamma.d (or gamma) It is possible to obtain a desired output power by optimizing the related thermal resistance and electrical resistance.

In applications where the operating temperature is near room temperature or up to about several hundreds of degrees Celsius, the thermoelectric material used for the thermoelectric thin films 12a and 12b can be a bismuth tellurium alloy, a full Heusler alloy, or a half Heusler alloy. The bismuth tellurium-based alloy is, for example, Bi ₂ Te _3-x Se _x as the n-type, and Bi _2-x Sb _x Te ₃ as the p-type, for example. The full Heusler alloy is, for example, Fe ₂ VAl _1-x Ge _x , Fe ₂ VAl _1-x Si _x or Fe ₂ VTa _x Al _1-x as n-type, and Fe ₂ V _1-x W _x as p-type, for example. Al, Fe ₂ V _1-x Ti _x Al or Fe ₂ V _1-x Ti _x Ga, and other materials such as Fe ₂ NbGa, Fe ₂ HfSi, Fe ₂ TaIn, Fe ₂ TiSn or Fe ₂ ZrGe . The half-Heusler-based alloy includes, for example, TiPtSn, (Hf _1-x Zr _x ) NiSn or NbCoSn as n-type, and TiCoSn _x Sb _1-x , Zr (Ni _1-x Co _x ) Sn, Zr (Ni _1-x In _x ) Sn, HfPtSn. By making the n-type thermoelectric material and the p-type thermoelectric material in the same material, the thermoelectric thin films 12a and 12b can be easily manufactured. In addition, when the temperature range to be used is sufficiently higher than room temperature, Si or SiGe alloy can be used as the thermoelectric material used for the thermoelectric thin films 12a and 12b.

The connection layers 14a and 14b are preferably made of a material having a high electrical conductivity and thermal conductivity. For example, a metal layer such as Cu, Al, Au, or Ag can be used. The connection layers 14a and 14b may be made of different materials.

As the heat conductive layers 16a and 16b, a material having a high thermal conductivity is preferable, and for example, a metal layer such as Cu, Al, Au, or Ag can be used. The heat conductive layers 16a and 16b may be insulator layers as long as the heat conductivity is large. The heat conductive layers 16a and 16b may be made of different materials. The connection layers 14a and 14b and the heat conductive layers 16a and 16b may be made of different materials.

As the insulating layers 18a and 18b (insulator), a material having a high insulating property and a thermal conductivity sufficiently smaller than those of the heat conductive layers 16a and 16b is preferable. As the insulating layers 18a and 18b, for example, an inorganic insulator such as silicon oxide or a porous material thereof, alkyl group-containing silica or similar oxide and insulator, resin (for example, acrylic resin, epoxy resin, vinyl chloride resin, silicone) Insulators such as resin, fluororesin, phenol resin, bakelite resin, polyethylene resin, polycarbonate resin, polystyrene resin, polypropylene resin) or rubber (natural rubber, ethylene propylene rubber, chloroprene rubber, silicon rubber, butyl rubber or polyurethane rubber), An insulating gas such as nitrogen or air, or a vacuum can be used. The insulating layers 18a and 18b can be formed using a CVD (Chemical Vapor Deposition) method, a sputtering method, or a spin coating method.

The insulating film 20 is preferably made of a material having high insulating properties and high thermal conductivity. For example, an inorganic insulator such as aluminum oxide can be used. The insulating film 20 may not be provided, but is preferably provided for insulation when the heat conductive layers 16a and 16b and the base portions 22a and 22b are conductors.

The base portions 22a and 22b are preferably made of a material having a high thermal conductivity. For example, a metal such as Cu, Al, Au, or Ag, or a ceramic such as Si or alumina can be used. The insulating film 20 may be formed on the base portions 22a and 22b by sputtering or CVD. When the base portions 22a and 22b are electrical insulators, the insulating film 20 may not be used. At least one of the base portions 22a and 22b can be formed using a sputtering method or a CVD method. Thereby, base 22a and 22b can be thinned. At least one of the base portions 22a and 22b can be formed by a plating method. Thereby, base 22a and 22b can be made into a film | membrane thick to some extent. When at least one of the base portions 22a and 22b is an oxide film or ceramic, a coating film by spin coating or the like can be used. As the base portions 22a and 22b, a structure (for example, fin structure or heat sink structure) and a material (for example, a heat dissipation sheet, a heat dissipation material including a volatile material or a heat absorption material having high heat exchange characteristics and heat dissipation characteristics, or Al having an anodized surface, etc. ) Can be used.

For Comparative Example 1 and Example 1, simulation was performed to optimize the thermal resistance and electrical resistance in a trade-off relationship. A trade-off parameter γ indicating the ratio of the thermoelectric thin films 12a and 12b to the area of the base portions 22a and 22b was used. The simulation was performed assuming a lumped constant circuit using the thermal conductivity, electrical conductivity, and Seebeck coefficient of each material. In the simulation, the dimensions D × D of the bases 22a and 22b, the temperature difference ΔT between the bases 22a and 22b, the electromotive force V _S by the Seebeck element, the film thickness t ₀ of the thermoelectric thin films 12a and 12b, and the trade-off parameter γ are set. The other dimensions were calculated.

The simulation conditions are shown below.
Thermoelectric thin film 12a: n-type _Fe 2 _{VAl 1-x} Ta x
Thermoelectric thin film 12b: p-type Fe ₂ V _1-x Ti _x Ga
Dimensionless figure of merit: 0.09
Connection layers 14a, 14b: Cu
Thermal conductive layers 16a, 16b: Cu
Insulating layer 18: SiO ₂
Insulating film 20: Al ₂ O ₃ , film thickness t _Al2O3 : 100 nm
Base 22a, 22b: Cu, film thickness t _HS : 1 mm
D x D: 10 mm x 10 mm
ΔT: 1K

[Simulation of Comparative Example 1]
The simulation was performed with t ₀ = 100 nm and V _S = 1V. FIGS. 5A to 5C are diagrams showing simulation results of the element pair number m ₀ , the element size γd, and the output power P _OUT with respect to γ in Comparative Example 1, respectively. Element logarithm _{m 0} Seebeck elements are a pair of the number of thermoelectric films 12a and 12b. The element size γd is the width of each thermoelectric thin film 12a and 12b in the X direction. The output power P _OUT is the maximum output power of the thermoelectric conversion device of the thermoelectric conversion device obtained by adjusting the load resistance. In this simulation, the temperature difference ΔT is optimized so as to always be 1K. In actual design, optimization is performed in consideration of the amount of heat input.

As shown in FIG. 5A, the number of element pairs m ₀ increases as γ increases. This is because the thermal resistance between the base portions 22a and 22b decreases as the trade-off parameter γ increases. For this reason, the electromotive force per Seebeck element 10 is reduced, and the number of series connection of Seebeck elements 10 is increased in order to secure the electromotive force V _S.

As shown in FIG. 5B, γd increases as γ increases. γ ² is the area ratio of the thermoelectric thin films 12a and 12b in D × D. γd is a dimensional ratio of the thermoelectric thin films 12a and 12b to d.

As shown in FIG. 5C, the output power P _OUT is about 11 μW and peaks when γ is about 0.12. From FIG. 5A and FIG. 5B, the element logarithm m ₀ and the element size γd at which the output power P _OUT peaks are obtained.

Next, the film thickness t ₀ of the thermoelectric thin films 12a and 12b was changed from 10 nm to 10000 nm, and the element logarithm m ₀ and the element size γd that maximized the output power P _OUT were calculated. A simulation was performed when ΔT = 1K and the electromotive force V _S was 1 V and 100 mV.

FIGS. 6 (a) and 6 (b), _P OUT, _{m 0} for _{t 0} in Comparative Example 1, .gamma.d, a diagram illustrating a simulation result of (1-γ) d and _{t Cu.} FIG. 6A and FIG. 6B are V _S = 1V and V _S = 100 mV, respectively. P _OUT represents the maximum value of output power. In FIGS. _6A and 6B, the output power is indicated as P _out . The same applies to the following figures.

As shown in FIGS. 6A and 6B, the output power P _OUT decreases as the film thickness t ₀ decreases. The film thickness to which a fine processing technique such as a normal dry etching method and a thin film forming technique such as a sputtering method or a CVD method can be applied is about 1000 nm or less, preferably about 100 nm. In this range, the output power P _OUT becomes very small.

FIG. 7 is a diagram illustrating simulation results of P _OUT , m ₀ , γd, (1-γ) d, and t _Cu with respect to V _S in Comparative Example 1. The film thickness _{t 0} is set to 100nm. As shown in FIG. 7, when V _S becomes smaller, P _OUT becomes smaller.

[Simulation of Example 1]
The simulation was performed with t ₀ = 100 nm and V _S = 100 mV. The simulation conditions are the same as in Comparative Example 1. The width in the X direction of the heat conductive layers 16a and 16b was the same as the width in the X direction of the connection layers 14a and 14b. FIG. 8A to FIG. 8C are diagrams illustrating simulation results of m ₀ , γd, and P _OUT for γ in Example 1, respectively. As shown in FIGS. 8A and 8B, there is no solution when γ <0.5. For 0.5 <γ, two solutions are obtained. A solution having a large electromotive force per Seebeck element and a small number of elements (solid line) and a solution having a small electromotive force per Seebeck element and a large number of elements (dotted line). As shown in FIG. 8C, the output power P _OUT is the same for the two solutions, and is maximum at γ = 0.5. A solution (solid line) with a small number of elements was adopted from the viewpoint of ease of element fabrication.

Then, when the electromotive force _{V S} is 100 mV, the thickness _{t 0} of the thermoelectric film 12a and 12b is changed from 10nm to 200 nm, output power _{P OUT} element logarithmic _{m 0} and element dimensions γd and becomes maximum (1- γ) d was calculated.

FIG. 9 is a diagram illustrating simulation results of P _OUT , m ₀ , γd, (1-γ) d, and t _Cu with respect to t ₀ in Example 1. As shown in FIG. 9, the output power P _OUT is 250 μW or more even when the film thickness t ₀ is 200 nm or less. P _OUT hardly depends on the film thickness t ₀ . 250 μW can be realized as P _{OUT at} about t ₀ = 100 nm suitable for microfabrication technology and thin film formation technology.

FIG. 10 is a diagram illustrating simulation results of P _OUT , m ₀ , γd, (1-γ) d, and t _Cu with respect to V _S in Example 1. The film thickness _{t 0} is set to 100nm. As shown in FIG. 10, P _OUT is large even when V _S is small. Even if V _S is 100 mV or less, 250 μW can be realized as P _OUT .

A BiTe material having a larger Seebeck coefficient is used as the thermoelectric material used for the thermoelectric thin films 12a and 12b. The insulating layers 18a and 18b are made of a material having a lower thermal conductivity than SiO ₂ such as resin. Furthermore, the output power P _OUT can be further improved by thinning the base portions 22a and 22b.

According to Example 1, the thermoelectric thin film 12a (first thermoelectric thin film) and the thermoelectric thin film 12b (second thermoelectric thin film) are alternately provided in the X direction (first direction parallel to the surfaces of the thermoelectric thin films 12a and 12b). Yes. Thermoelectric thin films 12a and 12b have opposite conductivity types. The connection layers 14a (first connection layer) and 14b (second connection layer) are electrically and thermally connected to the thermoelectric thin films 12a and 12b between the thermoelectric thin films 12a and 12b, and are alternately provided in the X direction. ing. The heat conductive layers 16a and 16b are thermally connected to the connection layers 14a and 14b, respectively, and extend in the Z direction (second direction intersecting the XY plane). Thereby, even if it uses the thin film of a thermoelectric material, output electric power _POUT can be enlarged.

Further, the heat conductive layers 16a and 16b are provided on the opposite sides to the surfaces of the thermoelectric thin films 12a and 12b. That is, the heat conductive layer 16a is thermally connected to the connection layer 14a and extends in the −Z direction (second direction intersecting the XY plane). The heat conductive layer 16b is thermally connected to the connection layer 14b and extends in the + Z direction (the direction opposite to the second direction). Thereby, the temperature difference of the X direction of the thermoelectric thin films 12a and 12b generate | occur | produces, and it can generate electric power. For example, the heat conductive layers 16a and 16b may be provided on the same side with respect to the surfaces of the thermoelectric thin films 12a and 12b by forming the base portions 22a and 22b in a comb shape.

The film thickness t ₀ of the thermoelectric thin films 12a and 12b is preferably 10 μm or less, and more preferably 5 μm or less. The film thickness t ₀ of the thermoelectric thin films 12a and 12b that can be formed by using a semiconductor integrated circuit manufacturing technique capable of increasing the degree of freedom of shape and size is 1 μm or less. Even in the case where the film thickness t ₀ is 1 μm or less, the output power P _OUT can be increased in Example 1 as compared with Comparative Example 1. In the simulation results of Example 1 and Comparative Example 1, the film thickness t ₀ is preferably 500 nm or less, and more preferably 200 nm or less.

The insulating layers 18a and 18b (insulators) penetrate the heat conductive layers 16a and 16b and have a lower thermal conductivity than the heat conductive layers 16a and 16b. When the heat conductive layers 16a and 16b are provided on the + Z side and the −Z side, the insulating layers 18a (first insulator) and 18b (second insulator) are disposed on the −Z direction side of the thermoelectric thin films 12a and 12b and The heat conductive layers 16a and 16b penetrate through the + Z direction side, respectively, and have a lower thermal conductivity than the heat conductive layers 16a and 16b. Thus, by using the insulating layers 18a and 18b, the thermal resistance of the portion other than the heat conductive layers 16a and 16b between the base portions 22a and 22b can be increased.

The thermoelectric thin films 12a and 12b extend in the Y direction (a third direction that is parallel to the surface and intersects the first direction). Thereby, the electrical resistance of the X direction of the thermoelectric thin films 12a and 12b can be made small. Length in the Y direction of the thermoelectric film 12a and 12b is preferably 10 times or more the thickness _{t 0,} and more preferably at least 100-fold, more preferably 1000 times or more.

Thermoelectric films 12a and 12b .gamma.d (X direction width) is greater than the thickness _{t 0} of the thermoelectric film 12a and 12b. Thereby, the thermal resistance of the X direction of the thermoelectric thin films 12a and 12b can be enlarged. The element size γd is preferably 2 times or more of the film thickness t ₀ , and more preferably 10 times or more.

[Modification 1 of Example 1]
FIG. 11A and FIG. 11B are cross-sectional views of the thermoelectric conversion device according to the first modification of the first embodiment. As shown in FIG. 11A, the X-direction width of the heat conductive layers 16a and 16b may be larger than the X-direction width of the connection layers 14a and 14b. As shown in FIG. 11B, the width in the X direction of the heat conductive layers 16a and 16b may be smaller than that of the connection layers 14a and 14b. Other configurations are the same as those of the first embodiment, and the description thereof is omitted.

[Modification 2 of Embodiment 1]
FIG. 12 is a plan view of the thermoelectric conversion device according to the second modification of the first embodiment. As shown in FIG. 12, a plurality of modules 30 are provided in the Y direction. Each module 30 includes a Seebeck element 10 arranged in the X direction between the electrodes 24a and 24b. The modules 30 are electrically and thermally separated by the insulating layer 18. Depending on the application, the modules 30 can be connected in series, connected in parallel, or combined electrically in series and parallel. By integrating the wiring connecting the modules 30 on the substrate, the internal resistance of the wiring can be reduced. Other configurations are the same as those of the first embodiment, and the description thereof is omitted.

[Modification 3 of Embodiment 1]
FIG. 13A and FIG. 13B are a cross-sectional view and a plan view of the thermoelectric conversion device according to the third modification of the first embodiment. As shown in FIG. 13A, a groove 28a is formed in the base portion 22a and the insulating layer 18a, and a groove 28b is formed in the base portion 22b and the insulating layer 18b. The insulating layers 18a and 18b are solid. The grooves 28a and 28b are a gas such as air or a vacuum and have a higher thermal conductivity than the insulating layers 18a and 18b. For this reason, even if the temperature difference between the bases 22a and 22b is the same, the temperature difference between the thermoelectric thin films 12a and 12b can be increased. As shown in FIG. 13B, the base portion 22b is provided with a plurality of grooves 28b. Similarly, the base portion 22a is provided with a plurality of grooves 28a. The grooves 28b are arranged in the X direction and the Y direction. The strength of the thermoelectric conversion device can be increased by dividing the groove 28b. The groove 28b may be provided so as to extend in the Y direction. Other configurations are the same as those of the first embodiment, and the description thereof is omitted.

According to Modification 3 of Example 1, the base 22a and the insulating layer 18a have the groove 28a (first groove) between the heat conductive layers 16a. The base 22b and the insulating layer 18b have a groove 28b (second groove) between the heat conductive layers 16a. Thereby, the temperature difference between the thermoelectric thin films 12a and 12b can be enlarged. The insulating layers 18a and 18b may all be removed to form the grooves 28a and 28b.

[Modification 4 of Example 1]
FIG. 14A is a cross-sectional view of the thermoelectric conversion device according to the fourth modification of the first embodiment. As shown in FIG. 14A, the positions of the thermoelectric thin films 12a and 12b in the Z direction are not the same. Other configurations are the same as those of the first embodiment, and the description thereof is omitted. Depending on the manufacturing method of the thermoelectric thin films 12a and 12b, the thermoelectric thin films 12a and 12b may not be located on the same XY plane.

FIG. 14B is another example of the fourth modification of the first embodiment. As shown in FIG. 14B, the connection layers 14a and 14b may be in contact with the thermoelectric thin film 12a in the + Z direction and in contact with the thermoelectric thin film 12b in the -Z direction. The heat conductive layer 16a may be thermally connected to the connection layers 14a and 14b via the thermoelectric thin film 12b, and the heat conductive layer 16b may be thermally connected to the connection layers 14a and 14b via the thermoelectric thin film 12a. The X direction width of the heat conductive layers 16a and 16b may be larger than the X direction width of the connection layers 14a and 14b. The X direction width of the heat conductive layers 16a and 16b may be smaller than that of the connection layers 14a and 14b. In FIG. 14B, since the thermoelectric thin film 12b, the connection layers 14a and 14b, and the thermoelectric thin film 12a are laminated in the Z direction, the thermoelectric thin films 12a and 12b and the connection layers 14a and 14b can be easily contacted.

[Modification 5 of Embodiment 1]
FIG. 14C is a cross-sectional view of the thermoelectric conversion device according to the fifth modification of the first embodiment. As shown in FIG. 14C, a plurality of layers 48 are stacked with the insulating film 20 between the base portions 22a and 22b. Each layer 48 includes the thermoelectric thin films 12a and 12b, the connection layers 14a and 14b, the heat conductive layers 16a and 16b, and the insulating layers 18a and 18b of the fourth modification of the first embodiment. The insulating film 20 is an electrical insulator and has high thermal conductivity. Other configurations are the same as those in the first embodiment, and a description thereof will be omitted.

According to the fifth modification of the first embodiment, the heat conductive layer 16a included in one of the adjacent layers among the plurality of layers 48 and the heat conductive layer 16b included in the other of the adjacent layers 48 are electrically Thermally connected through the insulating film 20. Thus, by using a thin thermoelectric material, the plurality of layers 48 can be thermally connected in series between the base portions 22a and 22b. Thereby, heat can be efficiently converted into electric power. The Seebeck element of the first embodiment and the first to third modifications thereof may be stacked as in the fifth modification of the first embodiment.

The thermoelectric conversion device according to the first embodiment and its modification can be used as a power source for a wearable device, a microcontroller, or a sensor. For example, a thermoelectric conversion device is worn on the body. Thereby, the thermoelectric conversion apparatus can generate electric power using heat radiation from the body, and supply the generated electric power to the wearable device or sensor. Further, the thermoelectric converter can be used for power generation by exhaust heat (heat from exhaust gas) from a car engine.

[Modification 6 of Example 1]
A sixth modification of the first embodiment is an example in which the thermoelectric conversion device according to the first embodiment and the modification is used as a Peltier element. FIG. 15A and FIG. 15B are cross-sectional views of an electronic device using the thermoelectric conversion device according to the sixth modification of the first embodiment. As shown in FIG. 15A, an integrated circuit element 52 is mounted on a substrate 58 such as a printed circuit board. The integrated circuit element 52 is, for example, a microprocessor or a SoC (System on a Chip). A heat conducting member 56, a thermoelectric conversion device 51, a heat conducting member 56, and a heat radiating member 54 are provided on the integrated circuit element 52. The thermoelectric conversion device 51 uses the thermoelectric conversion device according to the first embodiment and its modification as a Peltier element. The heat conducting member 56 is a metal layer that takes thermal contact, such as copper or indium. The heat radiating member 54 is, for example, a heat radiating fin. The materials exemplified in the second embodiment may be used for the heat conducting member 56 and the heat radiating member 54. As shown in FIG. 15B, the thermoelectric conversion device 51 may be directly mounted on the integrated circuit element 52.

As in the sixth modification of the first embodiment, the integrated circuit element 52 can be cooled by applying power to the thermoelectric conversion device 51 that is a Peltier element. As shown in FIG. 15A, the thermoelectric conversion device 51 may be mounted between the integrated circuit element 52 and the heat radiating member 54 via a heat conducting member 56. As shown in FIG. 15B, the thermoelectric conversion device 51 may be directly integrated on the integrated circuit element 52 using a semiconductor process. In this case, it is also possible to integrate the thermoelectric conversion device 51 directly above the portion where the rise in heat on the integrated circuit element 52 is particularly high. Accordingly, the problem of heat dissipation in the integrated circuit element 52 can be solved by forcibly cooling the integrated circuit element 52.

Example 2 is an example of an electronic device having a thermoelectric conversion device. FIG. 16 is a cross-sectional view of the electronic device according to the second embodiment. As shown in FIG. 16, in the electronic device 105, the power generation device 50 is provided between the integrated circuit element 52 and the heat dissipation member 54. The integrated circuit element 52 is mounted on the substrate 58. The power generation device 50 and the integrated circuit element 52 are thermally connected via a heat conducting member 56.

The power generation device 50 includes, for example, thermoelectric conversion devices according to comparative example 1, comparative example 2, example 1, and modifications thereof. One of the connection layers 14a and 14b in the thermoelectric conversion device is thermally connected to the heat conducting member 56 through one of the base portions 22a and 22b. The other of the connection layers 14a and 14b is thermally connected to the heat dissipation member 54 via the other of the base portions 22a and 22b.

The integrated circuit element 52 is a chip on which an integrated circuit such as SoC (System on chip) is formed or a package on which the integrated circuit chip is mounted. The integrated circuit element 52 may be a microprocessor or the like. The board | substrate 58 is a printed circuit board, for example. The heat conductive member 56 is preferably made of a material having a high heat conductivity. For example, a metal such as Cu, Al, Au, or Ag, ceramics, or a high heat conductive silicone resin can be used. The base portions 22 a and 22 b of the thermoelectric conversion device may be directly brought into contact with the integrated circuit element 52 without providing the heat conducting member 56. The heat radiating member 54 is, for example, a housing of an electronic device, a heat radiating plate subjected to anodizing, a heat radiating fin, or a heat radiating fan. The power generation device 50 may be a π-type thermoelectric conversion device and other thermoelectric conversion devices.

According to the second embodiment, when the integrated circuit element 52 operates, heat is generated in the integrated circuit element 52. The generated heat is conducted to the heat radiating member 54 via the heat conducting member 56 and the power generation device 50, and is radiated by the heat radiating member 54. As in Comparative Examples 1 and 2 and Example 1 and modifications thereof, the power generation device 50 includes thermoelectric thin films (thermoelectric materials) 12a and 12b provided between the connection layers 14a and 14b, and the connection layer 14a. 14b and thermoelectric conversion devices connected in series alternately. One of the connection layers 14 a and 14 b is thermally connected to the integrated circuit element 52, and the other of the connection layers 14 a and 14 b is connected to the heat dissipation member 54.

Thereby, it is possible to generate power using the temperature difference between the integrated circuit element 52 and the heat dissipation member 54. By using Example 1 and its modification as the power generation device 50, the output power of the power generation device 50 can be increased.

[Modification 1 of Embodiment 2]
FIG. 17 is a block diagram of an electronic device according to the first modification of the second embodiment. As illustrated in FIG. 17, the electronic device 106 includes a control circuit 60 and a power storage device 62 in addition to the electronic device 105 according to the second embodiment. The power storage device 62 is, for example, a secondary battery. External power 70 is supplied to the control circuit 60. The control circuit 60 supplies power 71 to the integrated circuit element 52. The control circuit 60 may supply electric power 71 having a plurality of voltages to the integrated circuit element 52 corresponding to the power supply voltage of the integrated circuit element 52.

The heat 80 generated in the integrated circuit element 52 is conducted or transmitted to the power generation device 50. In the power generation device 50, a part of heat is converted into electric power 72. The remaining heat 81 is conducted or transmitted to the heat dissipation member 54. Heat 82 is released from the heat dissipation member 54.

Electric power 72 generated by the power generation device 50 is output to the control circuit 60. The control circuit 60 supplies the power 72 generated by the power generation device 50 to the power storage device 62 or the integrated circuit element 52. The power storage device 62 stores the electric power 73 supplied from the control circuit 60. The power storage device 62 supplies power 74 to the control circuit 60. The control circuit 60 supplies the electric power 74 supplied from the power storage device 62 to the integrated circuit element 52 as electric power 71.

The control circuit 60 selects, for example, a charging mode and an operation assist mode. In the charging mode, the control circuit 60 mainly uses the power 72 generated by the power generation device 50 for charging the power storage device 62. As the power 71 supplied to the integrated circuit element 52, the external power 70 is mainly used. In the charging mode, the power consumption speed of the power storage device 62 can be reduced. Alternatively, the charging time of the power storage device 62 can be shortened as compared with the case where the power storage device 62 is charged only by an external power source.

In the operation assist mode, the control circuit 60 supplies the integrated circuit element 52 with the power 72 generated by the power generation device 50 and / or the power 74 discharged by the power storage device 62 in addition to the external power 70. In the operation assist mode, as compared with the case where the operation assist mode such as the charging mode is not used, if the operation speed of the integrated circuit element 52 is the same, the consumption of the external power 70 can be suppressed (that is, the power consumption is reduced). If the external power 70 is the same, the integrated circuit element 52 can be operated at a higher speed (that is, voltage boosted by thermoelectric power generation). In addition, the energy collected from the thermoelectric conversion device can hold data in the memory in the integrated circuit when the integrated circuit enters the sleep state. For this data retention, the operation assist mode and energy from the battery can also be used.

According to the first modification of the second embodiment, the power storage device 62 stores the power generated by the power generation device 50 and supplies the stored power to the integrated circuit element 52. Thereby, low power consumption and / or high-speed operation are possible.

[Modification 2 of Embodiment 2]
FIG. 18 is a block diagram of a power system according to a second modification of the second embodiment. As shown in FIG. 18, the power system 108 includes a control circuit 60 and a power recovery device 64 in addition to the electronic device 105. The control circuit 60 supplies external power 70 to the integrated circuit element 52. The power recovery device 64 recovers the electric power 72 generated by the power generation device 50 in the plurality of electronic devices 105. The power recovery device 64 supplies power 75, which is a collection of the recovered power 72, to the outside.

In a data center or the like, a large number of integrated circuit elements 52 such as microprocessors are operating. For this reason, enormous electric power is consumed. Therefore, a part of the heat generated in the integrated circuit element 52 is converted into electric power 72 in the power generation device 50. The electric power 72 is collected and reused. The electric power 75 to be reused is used for electric power for air conditioning or lighting of a data center, for example. Even if the recovered power 72 is about 10% of the power consumption of the integrated circuit element 52, it can be sufficiently used as power for air conditioning or lighting.

[Simulation using constant temperature animal model]
In the simulations of Comparative Example 1 and Example 1, the temperature difference ΔT applied to the thermoelectric converter is constant. This model is one of the evaluation methods for a single thermoelectric generator module. However, when the thermoelectric conversion device is used as the power source of the wearable device, the thermoelectric conversion device generates power using a temperature difference between the human body temperature and the atmospheric temperature. In such a case, the simulation is not appropriate. Therefore, a thermoelectric conversion device in Example 1 was simulated using a constant temperature animal model for the skin temperature of the human body.

FIG. 19A and FIG. 19B are diagrams showing a simulation model. FIG. 19A and FIG. 19B show a constant heat flow model and a constant temperature difference model, respectively. The constant heat flow corresponds to a constant current source model if expressed by an equivalent electric circuit, and the constant temperature difference corresponds to a constant voltage source model if expressed by an equivalent electric circuit. A constant current source model is generally used for performance evaluation of thermoelectric converters.

As shown in FIG. 19A, thermal resistances k _M and k _air are connected in series. k _M and k _air correspond to the thermal resistance of the thermoelectric converter and the thermal resistance between the thermoelectric converter and the atmosphere, respectively. Thermal resistance _{k M} and _{k air} to the series constant current source 66 (i.e. Teinetsu flow source) is provided. The constant current source model and constant heat flow through the k _M and k _air constant current source 66 is a power Q was placed on one end of the heat resistance k _M. The power Q corresponds to the power input from the human skin to the thermoelectric converter. However, the constant current source model, the temperature of the skin surface which depends on the thermal resistance k _M. This cannot express the human body which is a constant temperature animal. Thus, for example, when the thermal resistance k _M is large, it will put a large power Q for the heat flow constant. However, the power input from the human body is limited, and the constant current source model is not appropriate as a simulation model of a power source for wearable devices.

As shown in FIG. 19 (b), the thermal resistance _{k M} and _{k air} in series the constant voltage source 68 (i.e. constant temperature difference source) is provided. In the constant voltage source model, considering that the human body is a constant temperature animal, the temperature difference between the outside air and the skin surface is kept constant so that the temperature of the human skin surface is constant. That is, the constant voltage source 68 keeps the temperature difference ΔT _S applied to the thermal resistances k _M and k _air constant. The temperature difference ΔT applied to both sides of the thermoelectric converter varies depending on the thermal resistances k _M and k _air , but the skin surface temperature can be kept constant.

The structure of Example 1 is shown in FIGS. 4 (a) and 4 (b), and the structure of Comparative Example 1 is shown in FIGS. 2 (a) and 2 (b).
The simulation conditions are shown below.
Atmospheric thermal resistance k _air : 212.5 K / W
Thermoelectric thin films 12a and 12b
Seebeck coefficient S = S _p −S _n : 434 μV / K
Thermal conductivity λ = (λ _p + λ _n ) /2:1.43 Wm ⁻¹ K ⁻¹
Electrical resistivity ρ = (ρ _p + ρ _n ) / 2: 8.11 μΩm
Connection layers 14a and 14b: Cu
Film thickness t _Cu : 10 μm (Example 1), ≦ 10 μm (Comparative Example 1)
Thermal conductivity λ _Cu : 386 Wm ⁻¹ K ⁻¹
Electrical resistivity λ _Cu : 1.69 × 10 ⁻⁸ Ωm
Insulating layer 18: Vacuum D × D: 10 mm × 10 mm
ΔT _S : 10K
S _n and S _p are the Seebeck coefficients of the n-type and p-type thermoelectric thin films 12a and 12b, respectively, λ _n and λ _p are the thermal conductivities of the n-type and p-type thermoelectric thin films 12a and 12b, _{respectively,} and ρ _n and ρ _p is the electrical resistivity of the n-type and p-type thermoelectric thin films 12a and 12b, respectively. D is the length of one side of the module.

As described above, in the constant temperature animal model, the temperature difference ΔT _S between the skin surface temperature and the outside air temperature is constant at 10K. This corresponds to a case where the body temperature is 35 ° C. and the air temperature is 25 ° C., for example. The heat resistance k _air for heat dissipation by convection and radiation from the base of the thermoelectric converter was kept constant at 212.5 K / W regardless of temperature.

[Simulation of Example 1]
Example 1 was simulated using a constant temperature animal model. Similar to the simulation of ΔT is constant, the output power P _OUT tradeoff parameter is maximum γ and the output power P _OUT is optimized device logarithmic m ₀ to the maximum.

20A and 20B are diagrams showing simulation results of γd, (1-γ) d, ΔT, βΔT, V _S and P _OUT for γ and m ₀ in Example 1, respectively. βΔT is a temperature difference between both ends of each of the thermoelectric thin films 12a and 12b. Other parameters are the same as in the simulation with ΔT constant.

FIG. 20A is a diagram when γ is optimized at m ₀ = 100 pairs and t ₀ = 100 nm. As shown in FIG. 20A, when γ changes, P _OUT changes. Γ that maximizes P _OUT is an optimized γ. When P _OUT does not have a peak with respect to γ, γ that maximizes P _OUT within the range of γd ≧ 1 μm and (1-γ) d ≧ 1 μm was determined as an optimized γ.

FIG. 20B is a diagram when m ₀ is optimized at t ₀ = 100 nm. For each m ₀ , γ is optimized by the method of FIG. As shown in FIG. 20B, P _OUT changes when m ₀ changes. As shown in the figure, since m ₀ that takes the peak of P _OUT and V _S is different, for example, m ₀ that maximizes P _{OUT in} the range of V _S ≧ 100 mV may be optimized m _0. it can.

FIG. 21 is a diagram illustrating simulation results of γd, (1−γ) d, ΔT, βΔT, V _S and P _OUT with respect to t ₀ in Example 1. m ₀ is optimized at every t _{0 by} the method of FIG. As shown in FIG. 21, P _OUT is 100 μW or more when the film thickness t ₀ is 300 nm or less.

[Simulation of Comparative Example 1]
A simulation was performed for the π-type of Comparative Example 1 in the same manner as in Example 1 using a constant temperature animal model. FIG. 22 is a diagram illustrating simulation results of γd, (1-γ) d, ΔT, βΔT, V _S and P _OUT with respect to t ₀ in Comparative Example 1. Here, the minimum values of γd and (1-γ) d are limited to 1 μm. As shown in FIG. 22, P _OUT decreases as the film thickness t ₀ decreases. When the film thickness t ₀ is 1000 nm or less, P _OUT is 100 μW or less.

As described above, the same result as the simulation result with a constant ΔT was obtained even when the simulation using the thermostat animal model was used. That is, in Example 1, the output power P _OUT hardly depends on the film thickness t ₀ . On the other hand, in Comparative Example 1, the output power P _OUT decreases as the film thickness t ₀ decreases.

In Example 1, the reason why the output power P _OUT can be increased even if the film thickness t ₀ of the thermoelectric thin films 12a and 12b is made smaller than that in Comparative Example 1 will be described.

FIG. 23A and FIG. 23B are schematic cross-sectional views of thermoelectric conversion devices according to Comparative Example 1 and Example 1, respectively. As shown in FIG. 23A and FIG. 23B, the direction of the temperature difference ΔT is the Z direction in both Comparative Example 1 and Example 1. In Comparative Example 1, the direction of heat flow of the thermoelectric thin films 12a and 12b is the same Z direction as the temperature difference ΔT. In Example 1, the direction in which the heat flow of the thermoelectric thin films 12a and 12b flows is the X direction that intersects the temperature difference ΔT.

In Comparative Example 1, as shown in FIG. 23 (a), the thermal resistance k of the reduced thickness _{t 0} of the thermoelectric film 12a and 12b for the thinning of the thermoelectric film 12a and 12b thermoelectric films 12a and 12b is reduced. The temperature difference βΔT between both ends of each of the thermoelectric thin films 12a and 12b becomes small. As shown in FIG. 22, when the film thickness t ₀ becomes smaller, the temperature difference ΔT generated in the entire thermoelectric conversion device (module) becomes smaller, but βΔT becomes smaller than the temperature difference ΔT. As a result, the output power P _OUT is reduced.

In Example 1, as shown in FIG. 23 (b), the thermal resistance k of the reduced thickness _{t 0} of the thermoelectric film 12a and 12b for the thinning of the thermoelectric film 12a and 12b thermoelectric films 12a and 12b is increased. Accordingly, as shown in FIG. 21, the temperature difference ΔT generated in the entire thermoelectric conversion device is large, and the temperature difference βΔT and the temperature difference ΔT between both ends of each of the thermoelectric thin films 12a and 12b are almost the same. As a result, the output power P _OUT does not decrease even when the film thickness t ₀ decreases.

FIG. 24 is a diagram illustrating the current I and the output power P _OUT with respect to the output voltage V _{out in the} first embodiment. The film thickness t _{0 is set} to 100 nm, and the area S on the XY plane is changed from 20 cm ² to 120 cm ^{2 in} 20 cm ² steps. The maximum value of the output power P _OUT is the output power when the output is impedance matched. As shown in FIG. 24, the output power P _OUT peaks when the output voltage V _out is 1V. In the wristband type wearable device, the mounting area is about 100 cm ² . Even if the area S is about 100 cm ² , an output power P _{OUT of} about 10 mW can be obtained, which can be sufficiently applied to a healthcare device or a wearable device including short / medium distance communication.

In Comparative Example 1, the simulation was performed without the conditions of γd ≧ 1 μm and (1-γ) d ≧ 1 μm. FIG. 25 is a diagram showing simulation results of γd, (1-γ) d, ΔT, βΔT, V _S and P _OUT with respect to the minimum dimension in Comparative Example 1. The minimum dimension corresponds to d. The film thickness _{t 0} was set to 100nm. Also in Comparative Example 1, when the minimum dimension is reduced, the temperature difference ΔT of the entire thermoelectric conversion device is increased, and the temperature difference βΔT generated in the thermoelectric material is reduced from the difference with ΔT. As a result, the difference between the temperature differences βΔT and ΔT decreases, and the output power P _OUT increases. For example, when the minimum dimension is 1 μm or less, the output power P _OUT is 20 μW or more. When the minimum dimension is 100 nm or less, the temperature differences βΔT and ΔT are substantially the same, and the output power P _OUT is 100 μW or more.

Thus, even in the first comparative example, the output power P _OUT can be improved by reducing the minimum dimension. However, if the minimum dimension is made smaller than the micron order (for example, 1 μm), the cost for fine processing increases. In the first embodiment, the output power P _OUT can be increased even when the minimum dimension is 1 μm or more, and high output power can be realized at low cost.

As shown in FIGS. 2A and 2B, the thermoelectric thin films 12a and 12b are arranged in the surface direction of the base portions 22a and 22b. The connection layers 14a and 14b are thermally connected to the base portions 22a and 22b, respectively, and are alternately and thermally connected to the thermoelectric thin films 12a and 12b in the direction intersecting the plane direction (Z direction). . In such a π-type thermoelectric conversion device, as shown in FIG. 25, the output power can be reduced by setting the pitch (period: for example, the dimension γd and / or (1-γ) d) of the thermoelectric thin films 12a and 12b to 1 μm or less. P _OUT can be increased. The size of the thermoelectric thin films 12a and 12b is preferably 0.5 μm or less, and more preferably 0.1 μm or less. To generate thermoelectric films 12a and 12b in the thin-film technology, thermoelectric film 12a and 12b thickness _{t 0} of, preferably 10μm or less, more preferably 5 [mu] m. Further, the film thickness of the thermoelectric thin films 12a and 12b formed by using a semiconductor integrated circuit manufacturing technique is preferably 1 μm or less, more preferably 500 nm or less, and further preferably 200 nm or less. As shown in FIG. 25, the output power P _OUT can be increased even when the film thickness t0 is 100 nm.

FIG. 26 (a) is a plan view of the thermoelectric conversion device according to the fourth embodiment, and FIG. 26 (b) is a cross-sectional view taken along the line AA of FIG. 26 (a). FIG. 26A shows the base portions 22 a and 22 b and the thermoelectric conversion unit 44. As shown in FIGS. 26A and 26B, a thermoelectric conversion unit 44 is provided between the base portions 22a and 22b. The thermoelectric conversion unit 44 includes the thermoelectric thin films 12a and 12b, the connection layers 14a and 14b, and the insulating layer 18 as in FIGS. 2A and 2B of the first comparative example. The area of the thermoelectric conversion unit 44 is made smaller than the base portions 22a and 22b in plan view. A thermal insulator 46 is provided at a portion other than the thermoelectric conversion unit 44 between the base portions 22a and 22b. The thermal insulator 46 has a lower thermal conductivity than the thermoelectric thin films 12a and 12b, the connection layers 14a and 14b, and the base portions 22a and 22b. Thus, the thermal insulator 46 is an electrical and thermal insulator. The sizes of the bases 22a and 22b are D0 × D0, and the size of the thermoelectric conversion unit 44 is D × D.

About Example 4, it simulated using the thermostat animal model. In the simulation, D0 = 1 cm, t ₀ = 100 nm, ΔT _S was 10 K, the thermal insulator 46 and the insulating layer 18 were evacuated, and γd ≧ 1 μm and (1−γ) d ≧ 1 μm. Optimization was performed with γ and m ₀ .

FIG. 27 is a diagram illustrating simulation results of γd, (1-γ) d, ΔT, βΔT, V _S and P _OUT with respect to D in Example 4. As shown in FIG. 27, even if the thermoelectric conversion unit 44 is the same π type as in Comparative Example 1, the output power P _OUT increases as D decreases. When the thermoelectric conversion unit 44 is a π type, if the thermoelectric thin films 12a and 12b are uniformly dispersed in the region of D0 × D0, the connection layers 14a and 14b that electrically connect the thermoelectric thin films 12a and 12b become longer, Impedance increases. If the thermoelectric thin films 12a and 12b are housed in a narrow D × D range as in the fourth embodiment, the connection layers 14a and 14b are shortened, and the internal impedance can be reduced.

[Modification 1 of Example 4]
FIG. 28A is a plan view of a thermoelectric conversion device according to Modification 1 of Embodiment 4, and FIG. 28B is a cross-sectional view taken along line AA of FIG. FIG. 28A shows the base portions 22 a and 22 b and the thermoelectric conversion unit 44. As shown in FIGS. 28 (a) and 28 (b), the thermoelectric conversion unit 44 includes the thermoelectric thin films 12a and 12b, the connection layer 14a, the same as FIGS. 14b, having a heat conductive layer and an insulating layer. The area of the thermoelectric conversion unit 44 is made smaller than the base portions 22a and 22b in plan view. The thermal insulator 46 has a lower thermal conductivity than the thermoelectric thin films 12a and 12b, the connection layers 14a and 14b, and the base portions 22a and 22b. The sizes of the base portions 22a and 22b are D × D, and the length of the thermoelectric conversion unit 44 is L.

About the modification 1 of Example 4, it simulated using the thermostat animal model. In the simulation, D = 1 cm, t ₀ = 100 nm, ΔT _S is 10 K, the insulating layers 18 a and 18 b in the thermoelectric conversion unit 44 are porous silicon (thermal conductivity is 35.7 mWm ⁻¹ K ⁻¹ ), and a thermal insulator is used. 46 was porous silicon or vacuum, and γd ≧ 1 μm and (1-γ) d ≧ 1 μm. Optimization was performed with γ and m ₀ .

FIG. 29A is a diagram showing a simulation result of t _Cu , γd, m ₀ , V _S and P _OUT with respect to L in Modification 1 of Example 4, and FIG. 29B is a diagram showing L, γd with respect to t _Cu . , M ₀ , V _S and P _OUT are diagrams illustrating simulation results. The insulating layers 18a and 18b and the thermal insulator 46 in the thermoelectric conversion unit 44 are made of porous silicon. As shown in FIG. 29A, when the thermal insulator 46 is porous silicon, the output power P _OUT increases as L decreases. In this example, when L is about 30 μm, the output power P _OUT is maximized. As shown in FIG. 29B, when L is about 30 μm and t _Cu is about 500 μm, the output power P _OUT becomes maximum at about 20 μW. If the heat insulator 46 of porous silicon, in order to suppress the heat flow through the heat insulator 46, but P _OUT increases by increasing the t _Cu, the thermal resistance of the t _Cu is too large thermally conductive layer Since it becomes larger, P _OUT has a peak.

FIG. 30 is a diagram showing simulation results of L, γd, m ₀ , V _S and P _OUT with respect to t _Cu when the thermal insulator 46 is vacuum. The insulating layers 18a and 18b in the thermoelectric conversion unit 44 are made of porous silicon. As shown in FIG. 30, the output power P _OUT decreases as L and t _Cu decrease. When L and t _Cu are about 0.1 μm, the output power P _OUT is about 100 μW. Thus, when the thermal insulator 46 is evacuated, the output power P _OUT increases. Since the heat flow through the thermal insulator 46 hardly flows, the output power P _OUT can be increased even if t _Cu is thin.

[Modification 2 of Example 4]
FIG. 31 is a cross-sectional view of the thermoelectric conversion device according to the second modification of the fourth embodiment. As shown in FIG. 31, a holding wall 47 for holding a space between the base portions 22a and 22b in a vacuum 46a is provided. Other configurations are the same as those of the fourth embodiment and the first modification thereof, and the description thereof is omitted.

According to Example 4 and its modifications 1 and 2, the base 22a (first base) is thermally connected to the surface of a living body of a thermostat animal such as a human body. The base 22b (second base) is thermally connected to the atmosphere (air). The thermoelectric conversion unit 44 (thermoelectric conversion unit) is provided between the base portions 22a and 22b. The thermal insulator 46 is provided between the base portion 22a and the base portion 22b and outside the thermoelectric conversion unit 44, and has a thermal conductivity smaller than that of the thermoelectric thin films 12a and 12b, the base portion 22a, and the base portion 22b. Thereby, the output power P _OUT can be improved as in the simulation results of FIG. 27 and FIG. 29A to FIG.

The thermal insulator 46 may completely surround the thermoelectric conversion unit 44 in a plan view as shown in FIG. The thermal insulator 46 may be provided only on both sides of the thermoelectric conversion unit 44 in plan view as shown in FIG. 28A of the first modification of the fourth embodiment. The thermal insulator 46 may be provided only on one side of the thermoelectric conversion unit 44. The width in the X direction of the thermoelectric conversion unit 44 may be smaller than D. That is, at least one of the thermoelectric conversion units 44 in the ± X direction may be provided with the thermal insulator 46. In both cases of FIGS. 26A and 28A, the area of the thermoelectric conversion unit 44 is preferably 1/10 or less, more preferably 1/100 or less, of the areas of the base portions 22a and 22b in plan view.

As the thermal insulator 46, the material of the insulating layers 18a and 18b exemplified in the first embodiment can be used. For example, the thermal insulator 46 may be a solid layer such as porous silicon. As the porous silicon, for example, porous silicon using high-resistance silicon or porous silicon that is electrically and thermally insulated by oxidation or the like can be used. Thereby, base 22a and 22b can be reinforced. As the solid layer, a porous layer such as porous silica other than porous silicon can be used.

Further, as in Modification 2 of Example 4, the thermal insulator 46 is a gas layer or vacuum having a pressure lower than atmospheric pressure, and the holding wall 47 (holding portion) holds the vacuum. Thereby, the thermal conductivity of the thermal insulator 46 can be reduced as compared with the case where the thermal insulator 46 is a solid layer. Therefore, the output power P _OUT can be increased as shown in FIG. The thermal insulator 46 may be air at atmospheric pressure or other gas (for example, nitrogen). Also in the fourth embodiment, the thermal insulator 46 may be vacuum, atmospheric pressure air, or other gas. Moreover, in Example 4 and its modification, the insulating layers 18, 18a, and 18b (see FIG. 4B, etc.) in the thermoelectric conversion unit 44 may be vacuum, air, or other gases besides solids.

The thermal insulator 46 and the insulating layers 18, 18a and 18b may be the same material or different materials. The insulating layers 18, 18a and 18b may be solid layers for holding the thermoelectric thin films 12a and 12b and the connection layers 14a and 14b, and the thermal insulator 46 may be an air layer or a vacuum for increasing the output power P _OUT .

[Modification 3 of Example 4]
FIG. 32A is a plan view of a thermoelectric conversion device according to a third modification of the fourth embodiment, and FIG. 32B is a cross-sectional view taken along the line AA in FIG. As shown in FIGS. 32 (a) and 32 (b), a plurality of thermoelectric conversion units 44 corresponding to the thermoelectric conversion units 44 of the fourth embodiment are provided between the single base 22a and the single base 22b. ing. Each thermoelectric conversion unit 44 is surrounded by a thermal insulator 46 in plan view. The plurality of thermoelectric conversion units 44 may be electrically connected in series or in parallel.

[Modification 4 of Example 4]
FIG. 33A is a plan view of a thermoelectric conversion device according to a fourth modification of the fourth embodiment, and FIG. 33B is a cross-sectional view taken along the line AA in FIG. As shown in FIGS. 33 (a) and 33 (b), a thermoelectric conversion unit 44 corresponding to the thermoelectric conversion unit 44 of the fourth modification example 1 is provided between the single base portion 22a and the single base portion 22b. Are provided. Each thermoelectric conversion unit 44 is surrounded by a thermal insulator 46 in plan view. The plurality of thermoelectric conversion units 44 may be electrically connected in series or in parallel.

According to the third and fourth modifications of the fourth embodiment, a plurality of thermoelectric conversion units 44 that are separated from each other via the thermal insulator 46 are provided between the base portions 22a and 22b. With these interconnections, the output voltage and power can be set appropriately.

The preferred embodiments of the present invention have been described in detail above, but the present invention is not limited to such specific embodiments, and various modifications can be made within the scope of the gist of the present invention described in the claims.・ Change is possible.

DESCRIPTION OF SYMBOLS 10 Seebeck element 12a, 12b Thermoelectric thin film 14a, 14b Connection layer 16a, 16b Thermal conductive layer 18, 18a, 18b Insulating layer 20 Insulating film 22a, 22b Base 24a, 24b Electrode 28a, 28b Groove 44 Thermoelectric conversion unit 46 Thermal insulator 47 Holding wall 50 Power generation device 52 Integrated circuit element 54 Heat radiation member 60 Control circuit 62 Power storage device

Claims (18)

1. The first thermoelectric thin film and the second thermoelectric thin film having opposite conductivity types provided alternately in a first direction parallel to the surfaces of the first thermoelectric thin film and the second thermoelectric thin film;
   A first connection layer electrically and thermally connected to the first thermoelectric thin film and the second thermoelectric thin film between the first thermoelectric thin film and the second thermoelectric thin film and provided alternately in the first direction And a second connection layer;
   A first heat conductive layer and a second heat conductive layer that are thermally connected to the first connection layer and the second connection layer, respectively, and extend in a second direction intersecting the surface;
   A thermoelectric conversion device comprising:
2. The thermoelectric conversion device according to claim 1, wherein the first thermoelectric thin film and the second thermoelectric thin film have a thickness of 10 μm or less.
3. The said 1st heat conductive layer and the said 2nd heat conductive layer are provided in the mutually opposite side with respect to the surface of the said 1st thermoelectric thin film and the said 2nd thermoelectric thin film, The Claim 1 or 2 characterized by the above-mentioned. Thermoelectric converter.
4. The said 1st heat conductive layer and the said 2nd heat conductive layer penetrated, and comprise the insulator whose heat conductivity is smaller than the said 1st heat conductive layer and the said 2nd heat conductive layer. The thermoelectric conversion apparatus as described in any one of these.
5. The first thermoelectric thin film and the second thermoelectric thin film extend in a third direction parallel to the surface and intersecting the first direction;
   The length in the third direction of the first thermoelectric thin film and the second thermoelectric thin film is 10 times or more the film thickness of the first thermoelectric thin film and the second thermoelectric thin film. 5. The thermoelectric conversion device according to claim 4.
6. 6. The thermoelectric conversion according to claim 1, wherein a width of the first thermoelectric thin film and the second thermoelectric thin film in the first direction is larger than a thickness of the first thermoelectric thin film and the second thermoelectric thin film. apparatus.
7. The thermoelectric conversion device according to any one of claims 1 to 6, further comprising a first base and a second base that are thermally connected to the first heat conductive layer and the second heat conductive layer, respectively.
8. A first solid insulator through which the first thermal conductive layer penetrates and having a thermal conductivity smaller than that of the first thermal conductive layer;
   A solid second insulator through which the second heat conductive layer penetrates and having a lower thermal conductivity than the second heat conductive layer;
   A first base and a second base thermally connected to the first heat conductive layer and the second heat conductive layer, respectively;
   Comprising
   The first base and the first insulator have a first groove between the first heat conductive layers,
   The thermoelectric conversion device according to claim 3, wherein the second base and the second insulator have a second groove between the second heat conductive layers.
9. A plurality of layers including the first thermoelectric thin film, the second thermoelectric thin film, the first connection layer, the second connection layer, the first heat conductive layer, and the second heat conductive layer are stacked in a direction intersecting the surface. And
   The first heat conductive layer included in one of the adjacent layers among the plurality of layers and the second heat conductive layer included in the other of the adjacent layers are thermally connected. The thermoelectric conversion apparatus as described in any one of these.
10. A first base thermally connected to the surface of the living body of the thermostat animal;
    A second base thermally connected to the air;
    Provided between the first base and the second base, the first thermoelectric thin film, the second thermoelectric thin film, the first connection layer, the second connection layer, the first heat conductive layer, and the second A thermoelectric conversion unit comprising a heat conductive layer, wherein the first heat conductive layer and the second heat conductive layer are respectively connected to the first base and the second base;
    Thermal conductivity of the first thermoelectric thin film, the second thermoelectric thin film, the first base, and the second base provided between the first base and the second base and outside the thermoelectric conversion unit. A thermal insulator having a smaller thermal conductivity;
    The thermoelectric conversion device according to claim 1, wherein the thermoelectric conversion device is provided.
11. A first base thermally connected to the surface of the living body of the thermostat animal;
    A second base thermally connected to the air;
    A first thermoelectric material provided between the first base portion and the second base portion and having a conductivity type opposite to that of the first thermoelectric material provided between the first connection layer and the second connection layer; Two thermoelectric materials are alternately connected in series via the first connection layer and the second connection layer, and the first connection portion and the second connection portion are the first base portion and the second base portion, respectively. A thermoelectric conversion unit thermally connected to the
    Thermal conductivity of the first thermoelectric material, the second thermoelectric material, the first base, and the second base provided between the first base and the second base and outside the thermoelectric conversion unit. A thermal insulator having a smaller thermal conductivity;
    A thermoelectric conversion device comprising:
12. The thermoelectric conversion device according to claim 10 or 11, wherein the thermal insulator is a solid layer.
13. The thermal insulator is a gas layer or vacuum having a pressure below atmospheric pressure;
    The thermoelectric conversion device according to claim 10 or 11, wherein the thermoelectric conversion device includes a holding unit that holds the gas layer or vacuum.
14. The thermoelectric conversion according to any one of claims 10 to 13, further comprising a plurality of the thermoelectric conversion units spaced from each other via the thermal insulator between the first base and the second base. apparatus.
15. An integrated circuit element;
    A heat dissipating member that dissipates heat generated in the integrated circuit element;
    11. The thermoelectric conversion device according to claim 1, wherein the thermoelectric conversion device is provided between the integrated circuit element and the heat dissipation member, and the first thermal conductive layer is thermally connected to the integrated circuit element. A power generation device in which the second heat conductive layer is connected to the heat dissipation member;
    An electronic device comprising:
16. An integrated circuit element;
    A heat dissipating member that dissipates heat generated in the integrated circuit element;
    A first thermoelectric material provided between the first connection layer and the second connection layer and a second thermoelectric material having a conductivity type opposite to that of the first thermoelectric material are the first connection layer and the second connection. Thermoelectric conversion devices connected in series alternately via layers, provided between the integrated circuit element and the heat dissipation member, the first connection layer thermally connected to the integrated circuit element, A power generation device in which the second connection layer is connected to the heat dissipation member;
    An electronic device comprising:
17. 17. The electronic device according to claim 15, further comprising a power storage device that stores electric power generated by the power generation device and supplies the power to the integrated circuit element.
18. A first base and a second base;
    The first thermoelectric thin film and the second thermoelectric thin film arranged in the surface direction of the first base and the second base and having opposite conductivity types;
    The first thermoelectric thin film and the second thermoelectric thin film are alternately and thermally connected in a direction intersecting the plane direction, and are thermally connected to the first base and the second base, respectively. A connection layer and a second connection layer;
    Comprising
    The thermoelectric conversion device, wherein the size of the first thermoelectric thin film and the second thermoelectric thin film in the surface direction is 1 μm or less.

Images