Cooling device

Abstract

To provide a cooling device which can efficiently dissipate heat generated by a heat source.SOLUTION: A cooling device comprises: a first electrode which has an electromagnetic wave absorption structure having a microstructure that exhibits plasmon resonance so as to absorb electromagnetic waves generated by a heat source; a thermoelectric material which comes into contact with the first electrode; a second electrode which comes into contact with the thermoelectric material at a position different from that of the first electrode; and a heat dissipation source which is electrically connected to the first electrode, and is disposed outside the heat source.SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] The present invention relates to a cooling device. [Background technology]

[0002] Electronic components generate heat during operation. The heat generated by electronic components hinders the stable operation of the electronic components and causes a decrease in output of the electronic components.

[0003] Various methods have been proposed to release heat generated by electronic components. For example, water-cooled or air-cooled coolers are examples of cooling devices for cooling electronic components. Patent Document 1 discloses a heat dissipation material using a heat dissipating acrylic resin laminate that utilizes the radiative cooling effect. Patent Document 2 discloses a cooling device that uses carbon nanotubes, which have excellent thermal conductivity, as a heat sink. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] Patent Publication No. 2021-034587 [Patent Document 2] JP 2020-077875 A Summary of the Invention [Problem to be solved by the invention]

[0005] Water-cooled and air-cooled coolers cool electronic components from the outside, and cannot directly cool the heat inside. In addition, the heat dissipation material using radiation cooling as described in Patent Document 1 is not suitable for dissipating heat inside packaged electronic components. This is because the electromagnetic waves radiated by the heat dissipation material are reabsorbed inside the package. In addition, the heat sink using carbon nanotubes as described in Patent Document 2 requires control of the diameter and chirality of the carbon nanotubes to obtain sufficient performance, and is therefore not very versatile.

[0006] The present invention has been made in consideration of the above problems, and has an object to provide a new cooling device that can efficiently dissipate heat generated in a heat source. [Means for solving the problem]

[0007] In order to solve the above problems, the present invention provides the following means.

[0008] The cooling device according to a first embodiment includes a first electrode having an electromagnetic wave absorbing structure having a microstructure exhibiting plasmon resonance and absorbing electromagnetic waves generated by a heat source, a thermoelectric material in contact with the first electrode, a second electrode in contact with the thermoelectric material at a position different from the first electrode, and a heat dissipation source electrically connected to the first electrode and arranged outside the heat source.

[0009] In the cooling device according to the above aspect, the heat source may be an electronic component, and the first electrode may be formed on a package covering the electronic component at a position facing the heat source.

[0010] The cooling device according to the above aspect may include a plurality of the first electrodes, the thermoelectric materials, and the second electrodes. The first electrodes, the thermoelectric materials, and the second electrodes may be electrically connected in series, and one of the two thermoelectric materials in contact with the first electrodes may be an n-type thermoelectric material, and the other may be a p-type thermoelectric material.

[0011] In the cooling device according to the above aspect, when a direction from the heat source toward the first electrode is defined as a first direction, at least a portion of the second electrode may be positioned so as to overlap with the first electrode when viewed from the first direction.

[0012] The cooling device according to the above aspect may further include a support that supports the first electrode, the thermoelectric material, and the second electrode, and the support may be suspended from an inner surface of the package that faces the heat source.

[0013] The cooling device according to the above aspect may further include a support supporting the first electrode, the thermoelectric material, and the second electrode, the support being folded in a zigzag shape, and a top of the support protruding toward the heat source.

[0014] The cooling device according to the above aspect may further include a cooling mechanism. The heat release source may be in contact with the cooling mechanism. Effect of the Invention

[0015] The cooling device according to the above aspect can efficiently dissipate heat generated in the heat source. [Brief description of the drawings]

[0016] [Figure 1] 1 is a cross-sectional view of an electronic device including a cooling device according to a first embodiment. [Diagram 2] FIG. 2 is a plan view of a characteristic portion of the cooling device according to the first embodiment. [Diagram 3] FIG. 2 is a perspective view of a first electrode according to the first embodiment. [Figure 4] FIG. 1 is an explanatory diagram of a cooling system using a cooling device according to a first embodiment. [Diagram 5] FIG. 13 is a perspective view of a first electrode according to a first modified example. [Figure 6] FIG. 11 is a cross-sectional view of a first electrode according to a second modified example. [Figure 7] FIG. 13 is a cross-sectional view of a first electrode according to a third modified example. [Figure 8] FIG. 11 is a cross-sectional view of an electronic device including a cooling device according to a second embodiment. [Figure 9] FIG. 11 is a plan view of a characteristic portion of a cooling device according to a second embodiment. [Figure 10] FIG. 11 is a perspective view of a characteristic portion of a cooling device according to a second embodiment. [Figure 11] FIG. 11 is a cross-sectional view of an electronic device including a cooling device according to a third embodiment. [Figure 12] FIG. 11 is a cross-sectional view of an electronic device including a cooling device according to a fourth embodiment. [Figure 13] FIG. 13 is a cross-sectional view of an electronic device including a cooling device according to a fifth embodiment. [Figure 14] FIG. 13 is a plan view of a characteristic portion of a cooling device according to a fifth embodiment. [Figure 15] FIG. 1 is a schematic diagram of a model of the experimental system in Example 1. [Figure 16] The calculation results of the first embodiment are shown below. [Figure 17] FIG. 1 is a schematic diagram of an experimental system in Example 2. [Figure 18] FIG. 1 is a diagram showing the measurement results of Example 2 and Comparative Example 1. [Figure 19] FIG. 1 is a diagram showing the measurement results of Example 2 and Comparative Example 1. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0017] The present embodiment will be described in detail below. The following description is an example of the present invention, and the present invention is not limited thereto, and can be appropriately modified and implemented without departing from the gist of the present invention.

[0018] First, the directions are defined. In the following description, the X direction is one direction in the plane in which the electronic component spreads. The Y direction is a direction perpendicular to the X direction in the plane in which the electronic component spreads. The Z direction is the thickness direction of the electronic component, and is a direction perpendicular to the X and Y directions. For example, the direction from the heat source to the first electrode is an example of the Z direction. Hereinafter, the direction from the heat source to the first electrode may be treated as the +Z direction, and the opposite direction may be treated as the -Z direction. However, the terms "upper" and "lower" in this specification are used for convenience of description and do not specify the direction of gravity.

[0019] "First embodiment" 1 is a cross-sectional view of an electronic device 100 including a cooling device according to a first embodiment. The electronic device 100 includes, for example, an electronic component package and a cooling device.

[0020] The electronic component package includes an electronic component 70 and a package 80. The electronic component 70 may be any component that generates heat during operation. The electronic component 70 may be, for example, a CPU (Central Processing Unit), a memory, a hard disk, a highly integrated circuit, a light-emitting diode (LED), etc. The electronic component 70 is an example of a heat source.

[0021] The package 80 is provided to cover the electronic component 70 and protect the electronic component 70 from external shocks, humidity, gas, etc. The package 80 is made of, for example, resin, metal, ceramic, or the like.

[0022] The cooling device includes, for example, a first electrode 10 having an electromagnetic wave absorbing structure, a thermoelectric material 20, a second electrode 30, a heat emission source 40, wiring 50, and a cooling mechanism 60. The cooling device releases heat generated in the electronic component package to the outside, thereby cooling the electronic component package.

[0023] Fig. 2 is a plan view of a characteristic portion of the cooling device according to the first embodiment. Fig. 2 is a plan view of a surface of a package 80 facing an electronic component 70. Fig. 1 corresponds to a cross section taken along line AA in Fig. 2.

[0024] There are multiple first electrodes 10, thermoelectric materials 20, and second electrodes 30 on the inner surface of the package 80. A set of the first electrode 10, thermoelectric material 20, and second electrode 30 functions as a thermoelectric conversion element. The electromagnetic wave absorbing structure in the first electrode 10 generates localized heat during plasmon resonance, generating a temperature difference in the thermoelectric material 20. The thermoelectric material 20 converts this temperature difference into a potential difference by the Seebeck effect. The potential difference generated in the thermoelectric material 20 generates a current between the first electrode 10 and the second electrode 30.

[0025] The first electrode 10, the thermoelectric material 20, and the second electrode 30 are electrically connected in series between two wirings 50. The first electrode 10 and the second electrode 30 are connected via the thermoelectric material 20. For example, one of the multiple first electrodes 10 is referred to as the first electrode 10A. The first electrode 10A is in contact with two thermoelectric materials 20. One of the two thermoelectric materials 20 in contact with the first electrode 10A is an n-type thermoelectric material 21, and the other is a p-type thermoelectric material 22. The n-type thermoelectric material 21 and the p-type thermoelectric material 22 are alternately connected via the first electrode 10 or the second electrode 30.

[0026] The first electrode 10 has an electromagnetic wave absorbing structure that exhibits plasmon resonance. The electromagnetic wave absorbing structure may have any structure as long as it exhibits plasmon resonance. The electromagnetic wave absorbing structure may include an artificial structure called a metamaterial. When the electromagnetic wave absorbing structure is irradiated with electromagnetic waves, plasmon resonance occurs. The electromagnetic wave absorbing structure generates localized heat during plasmon resonance. The electromagnetic wave absorbing structure can absorb thermal energy by utilizing plasmon resonance even in an environment with a uniform temperature distribution.

[0027] 3 is a perspective view of the first electrode 10 according to the first embodiment. The first electrode 10 includes a substrate 11 and a plurality of laminates 12 formed on the substrate 11. The plurality of laminates 12 are an electromagnetic wave absorbing structure. Here, an example is shown in which a plurality of laminates 12 are formed on the substrate 11, but the number of laminates 12 formed on the substrate 11 may be one. The laminate 12 protrudes from the substrate 11 in the -Z direction, for example, toward the electronic component 70, which is a heat source. By providing the laminate 12 on the heat source side, the first electrode 10 can efficiently absorb thermal energy.

[0028] The substrate 11 preferably has excellent thermal conductivity. The substrate 11 is, for example, silver, copper, aluminum, etc. The substrate 11 also serves as an electrode of the thermoelectric conversion element. The width, thickness, etc. of the substrate 11 can be appropriately set according to the purpose.

[0029] The laminates 12 may be arranged regularly or randomly. The density of the laminates 12 on the substrate 11 is preferably high, and the laminates 12 are preferably not in contact with each other. The interval between two laminates 12 is preferably smaller than the maximum diameter of the laminates 12, for example.

[0030] The laminate 12 is formed by alternately stacking conductive layers 13 and dielectric layers 14. The laminate 12 has, for example, a plurality of pairs of conductive layers 13 and dielectric layers 14. In the laminate 12, the total number of conductive layers 13 and dielectric layers 14 is preferably two or more.

[0031] The laminate 12 has a plurality of conductive layers 13. For example, the minimum inclusive circle of at least one of the plurality of conductive layers 13 has a different diameter from the minimum inclusive circles of the other conductive layers 13. The minimum inclusive circle is the smallest circle that includes the outer periphery of the conductive layer 13 in the XY plane. For example, the size of the minimum inclusive circle of the conductive layer 13 that is closest to the substrate 11 among the plurality of conductive layers 13 is larger than the size of the minimum inclusive circle of the conductive layer 13 that is farthest from the substrate 11 among the plurality of conductive layers 13. When the laminate 12 has a plurality of conductive layers 13 with different minimum inclusive circles, the absorption wavelength range of the electromagnetic wave absorbing structure is broadened, and the efficiency of absorbing thermal energy is improved.

[0032] The diameter of the smallest inclusive circle of conductive layer 13 is determined by the environmental temperature at which thermal energy is extracted. For example, when the environmental temperature is 10° C. or more and 200° C. or less, the diameter of the smallest inclusive circle is set to 200 nm or more and 5 μm or less.

[0033] There is no particular limit to the external shape of the conductive layer 13 when viewed from the z direction. The external shape of the conductive layer 13 may be, for example, circular, polygonal, or the like. The thickness of the conductive layer 13 is, for example, 5 nm or more and 200 nm or less. The thicknesses of the conductive layers 13 may be the same or different. By designing the thickness of the conductive layer 13, the wavelength range of the thermal energy to be absorbed can be changed.

[0034] The conductive layer 13 contains a metal selected from the group consisting of Au, Pt, Ag, Cu, Pd, Al, Ti, Ta, Zr, Si, Sn, Pb, Ga, Ge, Co, Zn, Fe, In, and Ba. The conductive layer 13 may be an oxide or nitride containing these metal elements. The conductive layer 13 is preferably, for example, TiN, TaN, ZrN, TiZr, or HfN. These nitrides have high heat generation properties.

[0035] The dielectric layers 14 are located between the conductive layers 13. The dielectric constant of the dielectric layers 14 is, for example, 1 F / m or more and 50 F / m or less. When the dielectric constant of the dielectric layers 14 is in this range, the polarizability of the conductive layers 13 is increased.

[0036] The dielectric layer 14 is made of an insulating material, and may be, for example, a metal-containing compound such as MgF2, CaF2, SiO2, ZrO2, ZnO2, Al2O3, MnO2, MoO3, MgO, CaO, WO3, TiO2, BaTiO3, Si3N4, AlN, SiC, HfO2, or Rochelle salt, an olefin-based resin such as polyethylene, polypropylene, a cycloolefin polymer, or a norbornene-based resin, a fluorine-based resin such as polytetrafluoroethylene or polydifluoroethylene, a styrene-based resin such as polystyrene or AS resin, a cellulose-based resin such as cellulose acetate, an acrylic resin such as polymethyl methacrylate, a polyurethane resin, a polyester resin, a polycarbonate resin, an epoxy resin, a vinylidene chloride resin, a nylon, a urea resin, a polyacetal resin, a polyamide resin, or an organic compound such as polyethylene oxide.

[0037] The outer shape of the dielectric layer 14 when viewed from the z direction is not particularly limited. The outer shape of the dielectric layer 14 may be, for example, circular, polygonal, or the like. The thickness of the dielectric layer 14 is, for example, 5 nm or more and 200 nm or less. The thicknesses of the dielectric layers 14 may be the same or different. By designing the thickness of the dielectric layers 14, the wavelength range of the thermal energy to be absorbed can be changed.

[0038] The outermost surface of the laminate 12 is preferably a dielectric layer 14. The outermost dielectric layer 14 prevents the conductive layer 13 from oxidizing.

[0039] The thermoelectric material 20 is in contact with the first electrode 10. One end of the thermoelectric material 20 is connected to the first electrode 10, and the other end is connected to the second electrode 30. The thermoelectric material 20 is an n-type thermoelectric material 21 or a p-type thermoelectric material 22. The cooling device shown in FIG. 2 has both the n-type thermoelectric material 21 and the p-type thermoelectric material 22, but may have only one of them. The thermoelectric material 20 is, for example, a BiTe-based material, a BiSb-based material, or a BiSbTe-based material. The electromagnetic wave absorbing structure of the first electrode 10 generates localized heat by plasmon resonance, causing a temperature difference in the thermoelectric material 20. The thermoelectric material 20 converts this temperature difference into a potential difference.

[0040] The second electrode 30 contacts the thermoelectric material 20 at a position different from the first electrode 10. The second electrode 30 may be any material as long as it is conductive. The second electrode 30 may include, for example, metals such as copper, silver, gold, platinum, palladium, iron, titanium, and aluminum, and alloys thereof. It is preferable to use a metal for the second electrode 30 that does not oxidize or melt in the environment in which the second electrode 30 is used.

[0041] The heat emission source 40 is electrically connected to the first electrode 10. For example, as shown in Fig. 1, the heat emission source 40 is connected to the first electrode 10 via a wiring 50. The heat emission source 40 may be electrically connected to the first electrode 10 via the wiring 50, the second electrode 30, and the thermoelectric material 20. The wiring 50 may be any type as long as it is conductive.

[0042] The heat emission source 40 is disposed outside the electronic component package. The heat emission source 40 is preferably disposed at a position away from the electronic component package. The heat emission source 40 may be disposed on the cooling mechanism 60, for example.

[0043] The heat emission source 40 converts, into thermal energy, the electric energy generated in the thermoelectric conversion element consisting of the first electrode 10, the thermoelectric material 20, and the second electrode 30. The heat emission source 40 is, for example, a resistor, a capacitor, or the like.

[0044] The cooling mechanism 60 is a known cooling and heat dissipation structure such as an air-cooling unit, a water-cooling unit, or a heat sink. The cooling mechanism 60 is in contact with the heat emission source 40, for example. When the heat emission source 40 is in contact with the cooling mechanism 60, the efficiency of heat dissipation from the heat emission source 40 is increased. The cooling mechanism 60 may also be in contact with the electronic component 70. The cooling mechanism 60 cools the electronic component package from the outside of the electronic component package. When the cooling device uses a thermoelectric conversion element and the cooling mechanism 60 in combination, the electronic component 70 can be cooled from both the inside and the outside of the electronic component package, and the cooling efficiency of the electronic component 70 is increased. Note that if the amount of heat generated by the electronic component is not very high, the cooling mechanism 60 may not be required.

[0045] The cooling device of this embodiment can be produced by placing a thermoelectric conversion element consisting of a first electrode 10, a thermoelectric material 20, and a second electrode 30 inside an electronic component package, and connecting this thermoelectric conversion element to a heat dissipation source 40 outside the electronic component package.

[0046] The first electrode 10 can be produced by laminating the conductive layer 13 and the dielectric layer 14, and then patterning them into a desired shape. The conductive layer 13 and the dielectric layer 14 can be produced by, for example, PVD methods such as vacuum deposition, sputtering, and ion plating, CVD methods such as plasma polymerization, spin coating, and the like. The patterning can be performed by wet etching, dry etching, and the like using a mask. In addition, the electromagnetic wave absorbing structure of the first electrode 10 may be formed into a transferable substrate shape such as dimethylpolysiloxane (PDMS), and then the electromagnetic wave absorbing structure may be transferred to the substrate 11, etc. In addition, the first electrode 10 can also be produced by patterning a film such as a resist into a desired shape, laminating the conductive layer 13 and the dielectric layer 14 on the pattern, and lifting off the film such as the resist.

[0047] 4 is an explanatory diagram of a cooling system using a cooling device according to the first embodiment. The cooling system converts thermal energy H1 generated from an electronic component 70, which is a heat source, into electric energy E using a thermoelectric conversion element, and then converts the electric energy back into thermal energy H2, thereby cooling the electronic component 70 and the inside of a package 80.

[0048] 4, when the electronic component 70 is operated, heat is generated. The heat generates electromagnetic waves, and thermal energy H1 is released into the package 80.

[0049] The electromagnetic waves carrying thermal energy H1 undergo plasmon resonance in the electromagnetic wave absorbing structure of the first electrode 10. The plasmon resonance generates localized heat in the electromagnetic wave absorbing structure. The heat generated in the electromagnetic wave absorbing structure generates a temperature difference in the thermoelectric material 20. The thermoelectric material 20 converts the temperature difference into a potential difference by the Seebeck effect. The thermal energy H1 is converted into electrical energy E by thermoelectric conversion by the thermoelectric material 20.

[0050] The potential difference generated by the thermoelectric material 20 generates a current I between the first electrode 10 and the second electrode 30. The current I causes the resistor, which is the heat emission source 40, to generate heat according to Joule's law. That is, the resistor converts electric energy E into thermal energy H2. The heat emission source 40 emits the thermal energy H2. Since the heat emission source 40 is provided outside the package 80, the heat generated within the package 80 can be discharged to the outside.

[0051] As described above, the electronic device 100 according to the first embodiment has a thermoelectric conversion element made up of the first electrode 10, the thermoelectric material 20, and the second electrode 30 inside the electronic component package, and is thereby capable of converting thermal energy inside the electronic component package into electrical energy. Furthermore, the electronic device 100 according to the first embodiment has a heat dissipation source 40 outside the electronic component package, and is thereby capable of discharging the thermal energy inside the electronic component package that has been converted into electrical energy to the outside of the electronic component package. In other words, the electronic device 100 according to the first embodiment can efficiently dissipate heat generated inside the electronic component package to the outside of the electronic component package.

[0052] Although the present embodiment has been described above using one specific configuration, the specific examples of each component of the present embodiment are not limited to this example.

[0053] 5 is a perspective view of a first electrode 10' according to a first modified example. The first electrode 10' according to the first modified example can be substituted for the first electrode 10 described above.

[0054] The first electrode 10' comprises a substrate 11, a dielectric layer 15, and conductive particles 16. The dielectric layer 15 is on the substrate 11. The conductive particles 16 are scattered on the dielectric layer 15. The dielectric layer 15 is between each of the conductive particles 16 and the substrate 11. The substrate 11, the dielectric layer 15, and the conductive particles 16 form an electromagnetic wave absorbing structure.

[0055] The dielectric layer 15 is made of an insulating material. The dielectric layer 15 is made of, for example, a metal-containing compound such as MgF2, CaF2, SiO2, ZrO2, ZnO2, Al2O3, MnO2, MoO3, MgO, CaO, WO3, TiO2, BaTiO3, Si3N4, AlN, SiC, HfO2, Rochelle salt, or the like, an olefin-based resin such as polyethylene, polypropylene, cycloolefin polymer, or norbornene-based resin, a fluorine-based resin such as polytetrafluoroethylene or polydifluoroethylene, a styrene-based resin such as polystyrene or AS resin, a cellulose-based resin such as cellulose acetate, an acrylic resin such as polymethyl methacrylate, a polyurethane resin, a polyester resin, a polycarbonate resin, an epoxy resin, a vinylidene chloride resin, a nylon, a urea resin, a polyacetal resin, a polyamide resin, or an organic compound such as polyethylene oxide. The dielectric constant of the dielectric layer 15 is, for example, 1 F / m or more and 50 F / m or less. When the dielectric constant of the dielectric layer 15 is in this range, the polarizability of the conductive particles 16 is increased.

[0056] The conductive particles 16 may be regularly arranged or randomly disposed on the dielectric layer 15. By regularly arranging the conductive particles 16, the conductive particles 16 can be arranged at a high density on the dielectric layer 15, thereby improving the performance of the first electrode 10′.

[0057] The circle-equivalent diameter of the conductive particles 16 is, for example, 50 nm or more and 20.00 μm or less. When the circle-equivalent diameter of the conductive particles 16 is 50 nm or more and 20.00 μm or less, the first electrode 10' can efficiently absorb thermal energy in an environment with an environmental temperature of 10° C. or more and 500° C. or less. The circle-equivalent diameter range of the conductive particles 16 can be appropriately set according to the wavelength range of the thermal energy to be absorbed. As the circle-equivalent diameter of the conductive particles 16 increases, the absorption wavelength range of the thermal energy shifts to the long wavelength side. The circle-equivalent diameter is the diameter of a circle having an area equal to the area of ​​the conductive particles 16 in a plan view from the Z direction. The first electrode 10' may include conductive particles 16 having a circle-equivalent diameter outside the range of 50 nm or more and 20.00 μm or less. It is preferable that the conductive particles 16 outside the range of 50 nm or more and 20.00 μm or less are less than 10% of the total number of the conductive particles 16.

[0058] The average equivalent circle diameter (average particle size) of the conductive particles 16 is preferably 1 μm or more and 20 μm or less. When the average equivalent circle diameter of the conductive particles 16 is 1 μm or more and 20 μm or less, thermal energy can be absorbed more efficiently in an environment where the environmental temperature is 10° C. or more and 500° C. or less. In addition, the standard error of the equivalent circle diameter of the conductive particles 16 is preferably 0.05 μm or more and 0.20 μm or less.

[0059] The density of the conductive particles 16 when viewed in a plan view from the Z direction is 0.0025 particles / μm 2 The density of the conductive particles 16 is preferably 0.0025 particles / μm 2 If the density of the conductive particles 16 is 0.0090 particles / μm or more, the amount of thermal energy absorbed is increased. 2 More preferably, it is 1.0000 particles / μm or more. 2 The higher the density of the conductive particles 16, the more preferable it is. 2 It is preferable that:

[0060] The average interparticle distance of the conductive particles 16 in plan view from the Z direction is preferably 9.00 μm or less, more preferably 5.00 μm or less, and even more preferably 1.00 μm or less. The average interparticle distance is the average value of the distances between the centers of gravity of the conductive particles 16. The average interparticle distance of the conductive particles 16 may be 10 nm or more.

[0061] When the conductive particles 16 are in contact with each other, the total area of ​​the conductor increases in plan view from the Z direction, and the wavelength range of the heat energy that can be absorbed changes. As a result, the wavelength range of the heat energy that can be absorbed by the electromagnetic wave absorption structure of the first electrode 10' may become narrower. In this specification, when the conductive particles 16 are in contact with each other, the group of conductive particles 16 is regarded as one conductive particle 16. Therefore, the distance between the conductive particles 16 in plan view from the Z direction is preferably 1 nm or more, and more preferably 10 nm or more.

[0062] The conductive particles 16 include a metal selected from the group consisting of Au, Pt, Ag, Cu, Pd, Al, Ti, Ta, Zr, Si, Sn, Pb, Ga, Ge, Co, Zn, Fe, In, and Ba. The conductive particles 16 may be an oxide or nitride containing these metal elements. The conductive particles 16 are preferably, for example, TiN, TaN, ZrN, TiZr, or HfN. These nitrides have high heat generating properties.

[0063] The circle-equivalent diameter, density, and interparticle distance of the conductive particles 16 can be evaluated, for example, by the following method. The surface of the first electrode 10' is observed using a scanning electron microscope (SEM). The circle-equivalent diameter, density, average interparticle distance, and distance (shortest distance) between the conductive particles 16 are obtained from the SEM image (500 μm×500 μm) obtained by observation using image analysis software (e.g., ImageJ). For example, the circle-equivalent diameter can be obtained using image analysis software. The density can be obtained using image analysis software. The average interparticle distance can be obtained using image analysis software. The distance between the conductive particles 16 can be obtained using image analysis software. Whether or not a particle is a conductive particle can be determined, for example, by examining the ratio of elements that make up the conductive particle using an energy dispersive X-ray spectrometer (EDX) attached to the SEM.

[0064] The method for producing the first electrode 10' is not particularly limited. For example, the first electrode 10' may be obtained by dispersing conductive particles such as metal particles in a solvent, applying the dispersion on the dielectric layer 15, and drying the dispersion. Alternatively, the first electrode 10' may be obtained by forming a metal film on the dielectric layer 15 and then annealing the film at a predetermined temperature to form conductive particles made of metal. For example, when forming the conductive particles 16 by annealing, the particle size distribution of the conductive particles 16 can be controlled by the annealing temperature, time, and thickness of the metal film.

[0065] In the first electrode 10', the substrate 11, the dielectric layer 15, and the conductive particles 16 are arranged in the order of conductor, insulator, and conductor, and the conductive particles 16 have a predetermined size, so that the first electrode 10' absorbs thermal energy. Therefore, the first electrode 10' can use plasmon resonance to collect the surrounding thermal energy and generate localized heat. The heat generated in the first electrode 10' forms a temperature gradient in the thermoelectric material 20, and the thermal energy can be converted into electrical energy. Therefore, even when the first electrode 10' according to the first modification is used, the electronic device 100 according to the first embodiment can efficiently discharge the heat generated inside the electronic component package to the outside of the electronic component package.

[0066] For example, FIG. 6 is a cross-sectional view of a first electrode 10'' according to a second modified example. The first electrode 10'' according to the second modified example can be substituted for the first electrode 10 described above.

[0067] The first electrode 10'' includes a substrate 11 and a plurality of composite particles 17. The plurality of composite particles 17 are scattered on the substrate 11. The plurality of composite particles 17 include conductive particles 18 and a dielectric layer 19. The dielectric layer 19 covers the periphery of the conductive particles 18. The first electrode 10'' differs from the first electrode 10' in that, instead of the dielectric layer 15, the first electrode 10'' includes the dielectric layer 19 that covers the periphery of the conductive particles 18.

[0068] The conductive particles 18 are made of the same material and have the same size as the conductive particles 16 of the first electrode 10'. The dielectric layer 19 can be made of the same material as the dielectric layer 15 of the first electrode 10'. The thickness of the dielectric layer 19 is not particularly limited, but is preferably, for example, 5 nm or more and 200 nm or less.

[0069] The method for producing the first electrode 10'' is not particularly limited. For example, the first electrode 10'' can be produced by dispersing the composite particles 17 in a solvent, applying the dispersion onto the substrate 11, and drying the dispersion. The composite particles 17 can also be produced using a sol-gel method. For example, when the conductive particles 18 are silver nanoparticles, a dielectric layer 19 of SiO2 can be formed on the surface of the conductive particles 18 by adding tetraethoxysilane to an aqueous dispersion of silver nanoparticles and stirring the mixture for 1 to 60 minutes. The thickness of the dielectric layer 19 can be controlled by changing the stirring time.

[0070] In the first electrode 10'', the substrate 11, the dielectric layer 19, and the conductive particles 18 are arranged in the order of conductor, insulator, and conductor, and the composite particles 17 have a predetermined size, so that the first electrode 10'' absorbs thermal energy. Therefore, the first electrode 10'' can use plasmon resonance to collect the surrounding thermal energy and generate localized heat. The heat generated in the first electrode 10'' forms a temperature gradient in the thermoelectric material 20, and the thermal energy can be converted into electrical energy. Therefore, even when the first electrode 10'' according to the second modification is used, the electronic device 100 according to the first embodiment can efficiently discharge the heat generated inside the electronic component package to the outside of the electronic component package.

[0071] For example, Fig. 7 is a cross-sectional view of a first electrode 10''' according to a third modified example. The first electrode 10''' according to the third modified example can be substituted for the first electrode 10 described above.

[0072] The first electrode 10''' comprises a substrate 11, a wire 8, and conductive particles 9. The conductive particles 9 formed on the wire 8 form an electromagnetic wave absorbing structure.

[0073] The wire 8 transmits the heat absorbed by the conductive particles 9 to the substrate 11. The wire 8 may be, for example, a metal wire, a semiconductor (silicon) wire, or a conductive polymer.

[0074] The wires 8 protrude from the substrate 11. The wires 8 may be oriented perpendicular to one surface of the substrate 11, or may be oriented at an angle to the substrate 11. The wires 8 may be arranged at equal intervals or may be arranged randomly. Furthermore, the wires 8 may be oriented randomly, or may be entangled with each other.

[0075] The conductive particles 9 are attached to the surface of the wire 8. The conductive particles 9 may be made of the same material and have the same size as the conductive particles 16.

[0076] The method for manufacturing the first electrode 10''' is not particularly limited. For example, the first electrode 10''' can be manufactured by forming a wire 8 on the surface of the substrate 11 by patterning, applying a solvent containing conductive particles 9, and drying the resultant. Alternatively, the first electrode 10''' may be manufactured by forming a conductive polymer as a wire 8 on the surface of the substrate 11 by electrodeposition or electrospinning, applying a solvent containing conductive particles 9, and drying the resultant.

[0077] In the first electrode 10''', the conductive particles 9 absorb thermal energy, and the wire 8 propagates the absorbed heat. Therefore, the first electrode 10''' can utilize plasmon resonance to collect surrounding thermal energy and generate localized heat. The heat generated in the first electrode 10''' forms a temperature gradient in the thermoelectric material 20, and the thermal energy can be converted into electrical energy. Therefore, even when the first electrode 10''' according to the third modified example is used, the electronic device 100 according to the first embodiment can efficiently discharge heat generated inside the electronic component package to the outside of the electronic component package.

[0078] "Second embodiment" FIG. 8 is a cross-sectional view of an electronic device 101 including a cooling device according to a second embodiment. FIG. 8 is a plan view of a characteristic portion of the cooling device according to the second embodiment. FIG. 9 is a plan view of a surface of a package 80 facing an electronic component 70. FIG. 9 corresponds to a cross section taken along line AA in FIG. 8. FIG. 10 is a perspective view of a characteristic portion of the cooling device according to the second embodiment. FIG. 10 is a perspective view of a surface of a package 80 facing an electronic component 70.

[0079] The electronic device 101 includes, for example, an electronic component package and a cooling device. The electronic component package has an electronic component 70 and a package 80. The cooling device includes, for example, a first electrode 10, a thermoelectric material 20, a second electrode 30, a heat emission source 40, wiring 50, and a cooling mechanism 60. In the electronic device 101 according to the second embodiment, the same components as those in the electronic device 100 according to the first embodiment are denoted by the same reference numerals, and description thereof will be omitted. The cooling device releases heat generated in the electronic component package to the outside, and cools the electronic component package.

[0080] On the inner surface of the package 80, there are a plurality of laminates each including a first electrode 10, a thermoelectric material 20, and a second electrode 30. Each of the laminates includes the first electrode 10, the thermoelectric material 20, and the second electrode 30, in that order from the side closest to the electronic component 70.

[0081] Each of the second electrodes 30 is connected to two thermoelectric materials. One of the thermoelectric materials connected to the second electrode 30 is an n-type thermoelectric material 21, and the other is a p-type thermoelectric material 22. Each of the first electrodes 10 is connected to two thermoelectric materials. One of the thermoelectric materials connected to the first electrode 10 is an n-type thermoelectric material 21, and the other is a p-type thermoelectric material 22. The n-type thermoelectric material 21 and the p-type thermoelectric material 22 connected to one first electrode 10 are connected to different second electrodes 30. When viewed from the Z direction, at least a part of the second electrode 30 is in a position overlapping with the first electrode 10.

[0082] The first electrode 10 has an electromagnetic wave absorbing structure that exhibits plasmon resonance. When the electromagnetic wave absorbing structure is irradiated with electromagnetic waves, plasmon resonance occurs. The electromagnetic wave absorbing structure generates localized heat during plasmon resonance. The electromagnetic wave absorbing structure can absorb thermal energy by utilizing plasmon resonance even in an environment with a uniform temperature distribution.

[0083] The first electrode 10 may have any structure as long as it exhibits plasmon resonance, and examples thereof include the structures shown in Figures 3, 5, 6, and 7. The microstructure of the first electrode 10 is preferably located, for example, opposite the electronic component 70. By having the surface of the first electrode 10 on which the microstructure is formed opposite the electronic component 70, the electromagnetic wave absorbing structure can efficiently absorb thermal energy generated from the electronic component 70.

[0084] The electronic device 101 according to the second embodiment, like the electronic device 100 according to the first embodiment, has a thermoelectric conversion element made up of a first electrode 10, a thermoelectric material 20, and a second electrode 30 inside the electronic component package, and can convert thermal energy inside the electronic component package into electrical energy. Moreover, the electronic device 101 according to the first embodiment has a heat dissipation source 40 outside the electronic component package, and can discharge the thermal energy inside the electronic component package that has been converted into electrical energy to the outside of the electronic component package. That is, the electronic device 101 according to the second embodiment can efficiently discharge heat generated inside the electronic component package to the outside of the electronic component package.

[0085] Furthermore, in the electronic device 101 according to the second embodiment, by stacking the first electrode 10, the thermoelectric material 20, and the second electrode 30 in the Z direction, many electromagnetic wave absorbing structures can be arranged at positions facing the electronic component 70. Therefore, the first electrode 10 can more efficiently absorb the thermal energy generated by the electronic component 70. Therefore, the electronic device 101 according to the second embodiment can more efficiently discharge the heat in the electronic component package to the outside.

[0086] "Third embodiment" 11 is a cross-sectional view of an electronic device 102 including a cooling device according to a third embodiment. The electronic device 102 includes, for example, an electronic component package and a cooling device. The electronic component package includes an electronic component 70 and a package 80. The cooling device includes, for example, a first electrode 10, a thermoelectric material 20, a second electrode 30, a heat emission source 40, wiring 50, and a cooling mechanism 60. In the electronic device 102 according to the third embodiment, the same components as those in the electronic device 100 according to the first embodiment are denoted by the same reference numerals, and description thereof will be omitted. The cooling device releases heat generated in the electronic component package to the outside, and cools the electronic component package.

[0087] The first electrode 10, the thermoelectric material 20, and the second electrode 30 are formed on a support 35. The support 35 is suspended from the inner surface of a package 80, which is the surface facing an electronic component 70 that is a heat source. Although Fig. 11 illustrates an example in which the first electrode 10, the thermoelectric material 20, and the second electrode 30 are formed only on one surface of the support 35, the first electrode 10, the thermoelectric material 20, and the second electrode 30 may be formed on both surfaces of the support 35.

[0088] The first electrode 10 has an electromagnetic wave absorbing structure that exhibits plasmon resonance. The first electrode 10 may have any structure as long as it exhibits plasmon resonance, and examples thereof include the structures shown in Figs. 3, 5, 6, and 7. The electromagnetic wave absorbing structure of the first electrode 10 does not have to be formed on the surface facing the electronic component 70. Radiation occurs in all directions within the electronic component package. Even if the surface on which the electromagnetic wave absorbing structure is formed does not face the electronic component 70, the electromagnetic wave absorbing structure can absorb thermal energy.

[0089] The electronic device 102 according to the third embodiment, like the electronic device 100 according to the first embodiment, has a thermoelectric conversion element made up of a first electrode 10, a thermoelectric material 20, and a second electrode 30 inside the electronic component package, and can convert thermal energy inside the electronic component package into electrical energy. Moreover, the electronic device 102 according to the third embodiment has a heat dissipation source 40 outside the electronic component package, and can discharge the thermal energy inside the electronic component package that has been converted into electrical energy to the outside of the electronic component package. That is, the electronic device 102 according to the third embodiment can efficiently discharge heat generated inside the electronic component package to the outside of the electronic component package.

[0090] Furthermore, in the electronic device 102 according to the third embodiment, the first electrode 10, the thermoelectric material 20, and the second electrode 30 are formed on the support 35, and this support 35 is suspended from the surface facing the electronic component 70, so that a large number of first electrodes 10 can be arranged within the electronic component package. The more electromagnetic wave absorbing structures that are arranged within the electronic component package, the more thermal energy can be converted into electrical energy, and the more heat within the electronic component package can be discharged to the outside.

[0091] "Fourth embodiment" 12 is a cross-sectional view of an electronic device 103 including a cooling device according to the fourth embodiment. The electronic device 103 includes, for example, an electronic component package and a cooling device. The electronic component package includes an electronic component 70 and a package 80. The cooling device includes, for example, a first electrode 10, a thermoelectric material 20, a second electrode 30, a heat emission source 40, wiring 50, and a cooling mechanism 60. In the electronic device 103 according to the fourth embodiment, the same components as those in the electronic device 100 according to the first embodiment are denoted by the same reference numerals, and description thereof will be omitted. The cooling device releases heat generated in the electronic component package to the outside and cools the inside of the electronic component package.

[0092] The first electrode 10, the thermoelectric material 20, and the second electrode 30 are formed on a support 35. The support 35 is folded in a zigzag shape on the inner surface of the package 80, which is the surface facing the electronic component 70, which is a heat source. The top of the support 35 protrudes toward the electronic component 70. The support 35 is, for example, a film. The first electrode 10, the thermoelectric material 20, and the second electrode 30 are formed, for example, on the position of the inclined surface of the support 35.

[0093] The first electrode 10 has an electromagnetic wave absorbing structure that exhibits plasmon resonance. The first electrode 10 may have any structure as long as it exhibits plasmon resonance, and examples thereof include the structures shown in Figs. 3, 5, 6, and 7. The electromagnetic wave absorbing structure of the first electrode 10 does not have to be formed on the surface facing the electronic component 70. Radiation occurs in all directions within the electronic component package. Even if the surface on which the electromagnetic wave absorbing structure is formed does not face the electronic component 70, the electromagnetic wave absorbing structure can absorb thermal energy.

[0094] The electronic device 103 according to the fourth embodiment, like the electronic device 100 according to the first embodiment, has a thermoelectric conversion element made up of a first electrode 10, a thermoelectric material 20, and a second electrode 30 inside the electronic component package, and can convert thermal energy inside the electronic component package into electrical energy. Moreover, the electronic device 103 according to the fourth embodiment has a heat dissipation source 40 outside the electronic component package, and can discharge the thermal energy inside the electronic component package that has been converted into electrical energy to the outside of the electronic component package. That is, the electronic device 103 according to the fourth embodiment can efficiently discharge heat generated inside the electronic component package to the outside of the electronic component package.

[0095] Furthermore, in the electronic device 103 according to the fourth embodiment, the first electrode 10, the thermoelectric material 20, and the second electrode 30 are formed on the support 35, and the support 35 is folded in a zigzag shape and placed inside the electronic component package, so that many electromagnetic wave absorbing structures can be placed inside the electronic component package. The more electromagnetic wave absorbing structures that are placed in the electronic component package, the more thermal energy can be converted into electrical energy, and the more heat inside the electronic component package can be discharged to the outside.

[0096] "Fifth embodiment" FIG. 13 is a cross-sectional view of an electronic device 104 including a cooling device according to a fifth embodiment. The electronic device 103 includes, for example, an electronic component package and a cooling device. The electronic component package includes an electronic component 70 and a package 80. The cooling device includes, for example, a first electrode 10, a thermoelectric material 20, a second electrode 30, a heat emission source 40, wiring 50, and a cooling mechanism 60. FIG. 14 is a plan view of a characteristic portion of the cooling device according to the fifth embodiment. FIG. 14 is a plan view of a surface of the package 80 facing the electronic component 70. FIG. 14 corresponds to a cross section taken along the line AA in FIG. 13.

[0097] The electronic device 104 according to the fifth embodiment differs from the electronic device 100 according to the first embodiment in that the second electrode 30 is disposed outside the package 80. In the electronic device 104 according to the fifth embodiment, the same components as those in the electronic device 100 according to the first embodiment are denoted by the same reference numerals and will not be described. In the fifth embodiment, the structure of the electromagnetic wave absorbing structure of the first electrode 10 is not particularly limited, and examples thereof include the structures shown in Figs. 3, 5, 6 and 7.

[0098] The thermoelectric material 20 is disposed in an opening provided in the package 80. The thermoelectric material 20 connects a first electrode 10 inside the package 80 and a second electrode 30 outside the package 80. The thermoelectric material 20 is preferably flexible, and is preferably, for example, a carbon nanotube oriented film or a polymer thermoelectric conversion material.

[0099] The electronic device 104 according to the fifth embodiment, like the electronic device 100 according to the first embodiment, has the first electrode 10 inside the electronic component package, and can absorb thermal energy inside the electronic component package. Furthermore, the electronic device 104 according to the fifth embodiment has the second electrode 30 outside the electronic component package, and can increase the temperature difference between the first electrode 10 and the second electrode 30. The thermoelectric material 20 converts the temperature difference between the first electrode 10 and the second electrode 30 into electromotive force, and can therefore output more power. This power may be used to operate the cooling mechanism 60 or other equipment.

[0100] Although the preferred embodiment of the present invention has been described in detail above, the present invention is not limited to the specific embodiment, and various modifications and changes are possible within the scope of the gist of the present invention described in the claims.

[0101] For example, the heat source is not limited to the electronic component 70. For example, the heat source may be a car engine, a drive unit of a home appliance, a home appliance in a house, etc. In other words, the cooling device according to the present embodiment is not limited to electronic device packages, and can be applied to various systems in which heat accumulates. EXAMPLES

[0102] Example 1 In Example 1, a calculation model was constructed to determine the relationship between the number of thermoelectric conversion units and the amount of heat that the first electrode 10 can dissipate.

[0103] 15 shows a calculation model used in the first embodiment. In the first embodiment, a model in which a first electrode 0 is arranged inside a CPU package is assumed. The heat source 90 is silicon, and the heat source 90 is 2.53×10 9 W / m 3The heat source 90 generates heat. The first electrode 10, the thermoelectric material 20, and the second electrode 30 were arranged at a position facing the heat source 90. The first electrode 10 was a square with one side of 7.4 mm x 7.4 mm, and was a metamaterial with a heat absorption capacity of 0.166 W. Two thermoelectric materials 20 were connected to the first electrode 10, and each was made of bismuth telluride with a size of 1 mm x 0.5 mm. The second electrode 30 was connected to each of the two thermoelectric materials 20. One of the second electrodes 30 was a copper electrode with a size of 1 mm x 1 mm, and the other second electrode 30 was a copper electrode with a size of 1 mm x 2.5 mm. The experimental system including the heat source 90, the first electrode 10, the thermoelectric material 20, and the second electrode 30 was treated as being arranged in an insulated space surrounded by air.

[0104] Next, the amount of heat generated by a personal computer (PC) was estimated. The PC was assumed to be 22 cm long, 30 cm wide, and 2 cm thick, and the system was assumed to be one in which the PC was placed inside an aluminum exterior with a thickness of 1.5 mm. The volume of the aluminum exterior was 2×10 -4 m 3 The specific heat of aluminum is 0.942 J / (g K), and the density of aluminum (equivalent to 100°C) is 2.7 × 10 6 g / m 3 Therefore, the amount of heat (J / K) required to raise the temperature of the aluminum exterior by 1°C is 2×10 -4 m 3 ×0.942J / (g K)×2.7×10 6 g / m 3 ≒5.09×10 2 J / K.

[0105] For example, if the heat source of a PC heats up to 60°C in 5 minutes, the heat is 5.09 x 10 2 J / K×12K / min×60sec≒1.02×10 2 W of heat is applied to the aluminum exterior per unit time (minutes). If we assume that the area of ​​the heat generating part is 1 / 3 of the entire PC, then the heat is 1.02 x 10 2 The amount of heat generated is W÷3=34W.

[0106] FIG. 16 shows the calculation results of Example 1. The horizontal axis of FIG. 16 is the amount of heat absorbed by the electron absorption structure, and the vertical axis is the number of thermoelectric conversion units including the electron absorption structure required to offset the amount of heat generated by the PC. As shown in FIG. 16, the more the number of thermoelectric conversion units including the electron absorption structure increases, the greater the amount of heat absorbed by the electron absorption structure. When the amount of heat absorbed by this electron absorption structure matches the amount of heat generated by the PC, all of the heat generated by the CPU of the PC can be discharged to the outside by the thermoelectric conversion unit. For example, if the amount of heat generated by the CPU, 34 W, as shown in the above rough calculation, is to be discharged to the outside using the thermoelectric conversion unit, 204 thermoelectric conversion units are required. The area of ​​one thermoelectric conversion unit is approximately 7.4 × 7.4 mm 2 By using the configuration shown in Figs. 11 and 12, it can be placed inside the above-mentioned CPU package.

[0107] The above calculation is an estimate, and it is expected that there will be differences from the amount of heat generated by the actual device, but even if 10 times the amount of heat (340 W) is generated, with 2048 thermoelectric conversion units, the heat generated by the CPU can be dissipated. Furthermore, by using another cooling mechanism (for example, an air-cooled fan or a water-cooling mechanism) in addition to the thermoelectric conversion unit disclosed herein, the heat generated by the CPU can be sufficiently dissipated, and the heat generated by the PC can be suppressed.

[0108] Example 2 17 is a schematic diagram of an experimental system of Example 2. A thermoelectric conversion unit consisting of a first electrode 10, a thermoelectric material 20, and a second electrode 30 was formed on one surface of polystyrene foam 92. The size of the electromagnetic wave absorbing structure formed on the first electrode 10 was approximately 2.1×2.1 mm 2 The size of the first electrode and the second electrode 30 was 4 × 6 mm. 2 A thermistor 94 for measuring temperature was also provided on one surface of the polystyrene foam 92. A heat source 93 filled with hot water was placed in the insulated container 91, and the container was covered with the polystyrene foam 92. In the experimental system, the heat source 93 and the upper surface of the thermoelectric conversion unit faced each other inside the insulated container 91.

[0109] Comparative Example 1 Comparative Example 1 differs from Example 2 in that the first electrode 10 was changed to a normal electrode that did not have an electromagnetic wave absorbing structure. The other conditions were the same as those of Example 2.

[0110] Fig. 18 shows the progress of temperature change inside the insulated container 91 in Example 2 and Comparative Example 1. The temperature change was measured by a thermistor 94 placed inside the insulated container 91. Fig. 18 also shows the progress of output voltage from the thermoelectric conversion unit in Example 2 and Comparative Example 1. The solid line in Fig. 18 shows the progress of temperature change, and the dotted line shows the progress of output voltage.

[0111] 18, the temperature dropped more quickly in Example 2 than in Comparative Example 1. This is believed to be because the electromagnetic wave absorbing structure of Example 2 absorbed the heat inside the insulating container 91, converted it into electrical energy, and discharged it to the outside.

[0112] Furthermore, in Comparative Example 1, due to the temperature difference in the insulating container 91 caused by the convection therein, a slight thermoelectric output was shown immediately after the start, but after a certain time had passed, almost no thermoelectric output was shown. This is because the system shown in Comparative Example 1 does not have an electromagnetic wave absorbing structure, and therefore no electromotive force is generated in an environment with a uniform temperature distribution. In contrast, Example 2 showed thermoelectric output even after a certain time had passed. This is thought to be because in the system shown in Example 2, even in an environment with a uniform temperature distribution, the electromagnetic wave absorbing structure generates localized heat by utilizing plasmon resonance, and thermoelectric output can be obtained from the thermoelectric material 20.

[0113] In addition, reproducibility was confirmed by conducting four experiments using the same system as in Example 2 and three experiments using the same system as in Comparative Example 1. Figure 19 shows the measurement results of Example 2 and Comparative Example 1. The vertical axis of Figure 19 indicates the output voltage from the thermoelectric conversion unit, and the horizontal axis indicates the time it takes to reach 32.5°C.

[0114] 19, the output voltage from the thermoelectric conversion unit in Example 2 was larger than that in Comparative Example 1. This is believed to be because the electromagnetic wave absorbing structure generates localized heat by utilizing plasmon resonance even in an environment with a uniform temperature distribution, and thermoelectric output can be obtained from the thermoelectric material 20. Furthermore, in Example 2, the time required to reach 32.5 degrees is nearly 1000 seconds shorter than in Comparative Example 1, and it is clear that heat can be efficiently discharged from a closed environment to the outside. [Industrial Applicability]

[0115] The cooling device according to the present embodiment can be used to exhaust heat from electronic devices including CPUs, memories, LEDs, highly integrated circuits, etc. The cooling device according to the present embodiment can be applied not only to electronic devices but also to various systems where heat builds up. For example, the cooling device according to the present embodiment can be used to exhaust heat from inside home appliances, cars, homes, etc. [Explanation of symbols]

[0116] 8 Wire 10, 10', 10'', 10''', 10A 1st electrode 11 Substrate 12 Laminate 13 Conductive layer 14, 15, 19 Dielectric layers 9, 16, 18 Conductive particles 17 Composite particles 20 Thermoelectric materials 21 n-type thermoelectric materials 22 p-type thermoelectric material 30 2nd electrode 35 Support 40 Heat emission source 50 Wiring 60 Cooling mechanism 70 Electronic Components 80 packages 90, 93 Heat source 91 Insulated container 92 Styrofoam 94 Thermistor 100, 101, 102, 103, 104 Electronic devices

Claims

1. A first electrode having an electromagnetic wave absorbing structure having a microstructure exhibiting plasmon resonance and absorbing electromagnetic waves generated by a heat source; a thermoelectric material in contact with the first electrode; a second electrode contacting the thermoelectric material at a position different from the first electrode; a heat dissipation source electrically connected to the first electrode and disposed external to the heat source.

2. the heat source is an electronic component, The cooling device according to claim 1 , wherein the first electrode is formed at a position facing the heat source on a package that covers the electronic component.

3. The first electrode, the thermoelectric material, and the second electrode are each provided in a plurality of parts, the first electrode, the thermoelectric material, and the second electrode are electrically connected in series; The cooling device of claim 1 , wherein one of the two thermoelectric materials in contact with the first electrode is an n-type thermoelectric material and the other is a p-type thermoelectric material.

4. When a direction from the heat source toward the first electrode is defined as a first direction, The cooling device according to claim 1 , wherein at least a portion of the second electrode is positioned so as to overlap with the first electrode when viewed from the first direction.

5. a support supporting the first electrode, the thermoelectric material, and the second electrode; The cooling device of claim 1 , wherein the support is suspended from an inner surface of the package facing the heat source.

6. a support supporting the first electrode, the thermoelectric material, and the second electrode; The support is folded in a zigzag shape, The cooling device according to claim 1 , wherein a top of the support protrudes toward the heat source.

7. Further comprising a cooling mechanism; The cooling device according to claim 1 , wherein the heat dissipation source is in contact with the cooling mechanism.

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