Pi-type thermoelectric conversion module

Abstract

The invention provides a pi-type thermoelectric conversion module having excellent cooling performance in which reverse flow of heat is suppressed. A thermoelectric conversion member (A) including a thermoelectric conversion element (M) and a heat countercurrent suppression member (B) including a thermoelectric conversion element (K) are alternately disposed at intervals between a first substrate having a first electrode and a second substrate having a second electrode, the first substrate and the second substrate facing each other. The thermoelectric conversion member A and the thermal countercurrent suppression member B are electrically connected in series via the first electrode on the first substrate and the second electrode on the second substrate, carriers of the thermoelectric conversion element M and the thermoelectric conversion element K are different from each other, one is a hole, and the other is an electron, and the thermoelectric conversion element M and the thermoelectric conversion element K are electrically connected in series via the first electrode on the first substrate and the second electrode on the second substrate. The total SA (m2) of the surface area of the thermoelectric conversion member (A) joined to the first electrode and the second electrode is larger than the total SB (m2) of the surface area of the thermal countercurrent suppression member (B) joined to the first electrode and the second electrode.

Description

TECHNICAL FIELD

[0001] The present application relates to a π-type thermoelectric conversion module. BACKGROUND

[0002] Conventionally, as one of effective energy utilization methods, there has been a device that directly converts thermal energy and electric energy using a thermoelectric conversion module having a thermoelectric effect such as the Seebeck effect, the Peltier effect, and the like.

[0003] As the above thermoelectric conversion module, a thermoelectric conversion element of so-called π-type is known.

[0004] The π-type thermoelectric conversion element can be configured, for example, by disposing a pair of electrodes spaced apart from each other on a substrate, disposing a lower surface of a P-type thermoelectric element on one electrode and a lower surface of an N-type thermoelectric element on the other electrode, and connecting upper surfaces of the two types of thermoelectric elements to each other and to the electrodes on the opposed substrate, and by generally electrically connecting a plurality of such configurations in series within the two substrates and thermally connecting them in parallel.

[0005] In recent years, for products and the like that use a π-type thermoelectric conversion module including such a π-type thermoelectric conversion element and the like, various requirements for further improvement of thermoelectric performance, higher density, and reduction of constituent materials of the π-type thermoelectric conversion module have been proposed.

[0006] There are sometimes significant differences in thermoelectric performance between the P-type thermoelectric element and the N-type thermoelectric element, and for example, if a thermoelectric conversion module can be configured only by the P-type thermoelectric element, a significant performance improvement can sometimes be expected. For such a case, a thermoelectric conversion module configured only by the P-type thermoelectric element (referred to as a uni-leg type thermoelectric conversion module) has been designed by using a conductive member instead of the N-type thermoelectric element. However, for the uni-leg type thermoelectric conversion module, since the N-type thermoelectric element is not used, there is a problem that heat transferred from the P-type thermoelectric element is reversed and flows back to the P-type thermoelectric element due to heat transfer of the conductive member.

[0007] In Patent Literature 1, for example, a configuration in which a P-type thermoelectric conversion element as a P-type thermoelectric conversion member and an N-type thermoelectric conversion element as an N-type thermoelectric conversion member are combined with a laminate of a conductive member as shown in FIG. 1 of Patent Literature 1 is disclosed. Figure 3

[0008] Prior Art Documents

[0009] Patent Literature

[0010] Patent Literature 1: Japanese Patent Application Laid-Open No. 2018-157136 SUMMARY​

[0011] Problem to be solved by the Invention

[0012] However, in the thermoelectric conversion module of Patent Literature 1, the above-described configuration is adopted only for the purpose of suppressing occurrence of thermal stress caused by a difference in thermal expansion between the P-type thermoelectric conversion member and the N-type thermoelectric conversion member in a use environment (100°C, 300°C, 500°C). In addition, there is no description or suggestion as to how a difference in area of the respective upper and lower surface sides of the P-type thermoelectric conversion member and the N-type thermoelectric conversion member joined to the electrodes affects thermoelectric properties and the like.

[0013] The present application has been achieved in view of such actual circumstances, and a problem is to provide a π-type thermoelectric conversion module having excellent cooling performance in which a reverse flow of heat is suppressed.

[0014] Method of solving the problem

[0015] The present inventors and others have conducted intensive studies in order to solve the above problem, and as a result, have found that, by configuring a π-type thermoelectric conversion module in which a thermoelectric conversion member A including a thermoelectric conversion element M and a heat reverse flow suppressing member B including a thermoelectric conversion element K are alternately and separately arranged, making the respective carriers of the thermoelectric conversion element M and the thermoelectric conversion element K different from each other, and making the sum S A (m 2 ) of the areas of the surface sides of the thermoelectric conversion member A joined to the first electrode and the second electrode greater than the sum S B (m 2 ) of the areas of the surface sides of the heat reverse flow suppressing member B joined to the first electrode and the second electrode, it is possible to suppress a reverse flow of heat between the thermoelectric conversion element M and the thermoelectric conversion element K, and thus to have excellent cooling performance, and the present application has been completed.

[0016] That is, the present application provides the following [1] to [4].

[0017] [1] A π-type thermoelectric conversion module in which a thermoelectric conversion member A including a thermoelectric conversion element M and a heat reverse flow suppressing member B including a thermoelectric conversion element K are alternately and separately arranged between a pair of opposing substrates having a first electrode and a second electrode, and the thermoelectric conversion member A and the heat reverse flow suppressing member B are electrically connected in series via the first electrode on the first substrate and the second electrode on the second substrate,

[0018] the respective carriers of the thermoelectric conversion element M and the thermoelectric conversion element K are different from each other, one being a hole and the other being an electron,

[0019] the sum S of the areas of the surface sides of the thermoelectric conversion member A joined to the first electrode and the second electrode is greater than the sum SA (m 2 ) is greater than the sum S of areas of the side of the heat reverse flow suppressing member B that is joined to the first electrode and the second electrode B (m 2 ).

[0020] [2] The π-type thermoelectric conversion module according to the above-mentioned [1], wherein

[0021] S A is greater than the sum S of areas of the side of the heat reverse flow suppressing member B that is joined to the first electrode and the second electrode A is greater than the sum S of areas of the side of the heat reverse flow suppressing member B that is joined to the first electrode and the second electrode B is greater than the sum S of areas of the side of the heat reverse flow suppressing member B that is joined to the first electrode and the second electrode A is greater than the sum S of areas of the side of the heat reverse flow suppressing member B that is joined to the first electrode and the second electrode A is greater than the sum S of areas of the side of the heat reverse flow suppressing member B that is joined to the first electrode and the second electrode B is greater than the sum S of areas of the side of the heat reverse flow suppressing member B that is joined to the first electrode and the second electrode

[0022] S A is the sum of areas of the side of the thermoelectric conversion member A that is joined to the first electrode and the second electrode

[0023] S B is the sum of areas of the side of the heat reverse flow suppressing member B that is joined to the first electrode and the second electrode.

[0024] [3] The π-type thermoelectric conversion module according to the above-mentioned [1] or [2], wherein

[0025] the heat reverse flow suppressing member B includes the thermoelectric conversion element K and the conductive member, and the thermoelectric conversion element K and the conductive member have a constitution that is stacked in the direction in which the first substrate and the second substrate face each other.

[0026] [4] The π-type thermoelectric conversion module according to the above-mentioned [3], wherein

[0027] the height of the thermoelectric conversion element M in the thickness direction of the thermoelectric conversion member A is higher than the height of the thermoelectric conversion element K in the thickness direction of the heat reverse flow suppressing member B that has the conductive member.

[0028] Effects of the Invention

[0029] According to the present application, it is possible to provide a π-type thermoelectric conversion module that has excellent cooling performance in which the reverse flow of heat is suppressed. BRIEF DESCRIPTION OF DRAWINGS

[0030] Figure 1 is a cross-sectional structure diagram showing an embodiment (constitution A) of the π-type thermoelectric conversion module of the present application.

[0031] Figure 2is a cross-sectional structural view showing an embodiment (configuration B) of the π-type thermoelectric conversion module of the present application.

[0032] Figure 3 is a cross-sectional structural view showing an embodiment (configuration C) of the existing thermoelectric conversion module.

[0033] Figure 4 is a cross-sectional structural view showing an embodiment (configuration D) of the existing π-type thermoelectric conversion module.

[0034] Symbol explanation

[0035] 1: π-type thermoelectric conversion module

[0036] 11: π-type thermoelectric conversion module

[0037] 21: thermoelectric conversion module (single-leg type)

[0038] 31: π-type thermoelectric conversion module (existing type)

[0039] 2a: 1st substrate

[0040] 2b: 2nd substrate

[0041] 3a: 1st electrode

[0042] 3b: 2nd electrode

[0043] 4a: thermoelectric conversion member A

[0044] 4a1: thermoelectric conversion element M

[0045] 4b: heat backflow suppression member B

[0046] 4b1: thermoelectric conversion element K

[0047] 4b2: electrically conductive member DETAILED DESCRIPTION

[0048] [Thermoelectric conversion module]

[0049] The π-type thermoelectric conversion module of the present application is provided with a thermoelectric conversion member A containing a thermoelectric conversion element M and a heat backflow suppression member B containing a thermoelectric conversion element K, which are alternately and separately arranged between a pair of opposing substrates having a 1st electrode and a 2nd electrode, and the thermoelectric conversion member A and the heat backflow suppression member B are electrically connected in series via the 1st electrode on the 1st substrate and the 2nd electrode on the 2nd substrate,

[0050] The thermoelectric conversion element M and the thermoelectric conversion element K are different from each other in the type of carrier, one being a hole and the other being an electron,

[0051] The sum S of the areas of the side of the thermoelectric conversion member A that is bonded to the first electrode and the second electrode A (m 2 ) is greater than the sum S of the areas of the side of the thermorelectric flow suppression member B that is bonded to the first electrode and the second electrode B (m 2 ).

[0052] In the present application, in the configuration of a π-type thermoelectric conversion module in which a thermoelectric conversion member A including a thermoelectric conversion element M and a thermorelectric flow suppression member B including a thermoelectric conversion element K are alternately arranged, the carriers (holes, electrons) possessed by the thermoelectric conversion element M and the thermoelectric conversion element K are set to different combinations. For example, by setting the thermoelectric conversion element M to a P-type thermoelectric conversion element in which the carrier is a hole and setting the thermoelectric conversion element K to an N-type thermoelectric conversion element in which the carrier is an electron, compared to a combination of a thermoelectric conversion element of one carrier and a conductive member (so-called single leg type), thermoreverse flow from the thermorelectric flow suppression member B to the thermoelectric conversion member A can be suppressed. Further, the sum S of the areas of the side of the thermoelectric conversion member A that is bonded to the first electrode and the second electrode A (m 2 ) is greater than the sum S of the areas of the side of the thermorelectric flow suppression member B that is bonded to the first electrode and the second electrode B (m 2 ). Thus, the thermoelectric conversion member A having a thermoelectric conversion element M having more excellent thermoelectric properties can be used in a relatively large area, and thus a π-type thermoelectric conversion module having more excellent cooling performance can be obtained.

[0053] In the present specification, the thermoelectric conversion element M and the thermoelectric conversion element K are sometimes simply referred to as "thermoelectric conversion elements". In addition, the first substrate and the second substrate are sometimes simply referred to as "substrates". Furthermore, the first electrode and the second electrode are sometimes simply referred to as "electrodes".

[0054] In the present specification, the preferred limitations can be arbitrarily selected, and the combination of the preferred limitations with each other can be considered to be more preferred.

[0055] In the present specification, the notation of "XX ~ YY" means "from XX or more to YY or less".

[0056] In the present specification, for the preferred numerical range (for example, the range of the content, etc.), the lower limit value and the upper limit value of the stepwise notation can be independently combined with each other. For example, according to the notation of "preferably 10 ~ 90, more preferably 30 ~ 60", "the preferred lower limit value (10)" and "the more preferred upper limit value (60)" can be combined to obtain "10 ~ 60".

[0057] The thermoelectric conversion member A includes a thermoelectric conversion element M.

[0058] In addition, the thermal backflow suppression member B includes a thermoelectric conversion element K.

[0059] Details of the thermoelectric conversion element M and the thermoelectric conversion element K are described later.

[0060] Hereinafter, a π-type thermoelectric conversion module of the present application is described using the drawings.

[0061] Figure 1 is a cross-sectional structural view showing an embodiment (configuration A) of a π-type thermoelectric conversion module of the present application. The π-type thermoelectric conversion module 1 is configured so that a thermoelectric conversion member A 4a including a thermoelectric conversion element M 4al and a thermal backflow suppression member B 4b including a thermoelectric conversion element K 4bl are alternately and separately arranged between a pair of opposing first and second substrates 2a and 2b having first and second electrodes 3a and 3b, and the thermoelectric conversion member A 4a and the thermal backflow suppression member B 4b are electrically connected in series via the first electrode 3a on the first substrate 2a and the second electrode 3b on the second substrate 2b.

[0062] Here, for example, the π-type thermoelectric conversion module 1 is configured so that the area of the upper and lower surfaces (not shown) of the thermoelectric conversion member A 4a including the thermoelectric conversion element M 4al, which are bonded to the first electrode 3a side or the second electrode 3b side, is larger than the area of the upper and lower surfaces (not shown) of the thermal backflow suppression member B 4b including the thermoelectric conversion element K 4bl, which are bonded to the first electrode 3a side or the second electrode 3b side.

[0063] The sum S of the areas of the surfaces of the thermoelectric conversion member A, which are bonded to the first and second electrodes A The ratio R [= S A / (S B +S A )] of the sum S of the areas of the surfaces of the thermoelectric conversion member A, which are bonded to the first and second electrodes, to the sum S of the areas of the surfaces of the thermal backflow suppression member B, which are bonded to the first and second electrodes A B is preferably 0.55 or more and less than 0.95, more preferably 0.65 or more and less than 0.95, further preferably 0.75 to 0.93, and particularly preferably 0.80 to 0.90.

[0064] By making the ratio R 0.55 or more, the amount of heat absorption per unit area of the thermoelectric conversion element M included in the thermoelectric conversion member A can be easily increased.

[0065] ​By making the ratio R smaller than 0.95, heat backflow from the heat backflow inhibiting member B to the thermoelectric conversion member A can be easily inhibited, and the heat absorption amount per unit area of the thermoelectric conversion element K included in the heat backflow inhibiting member B can be maintained at a high level.

[0066] Preferably, the heat backflow inhibiting member B includes the thermoelectric conversion element K and the electrically conductive member, and the thermoelectric conversion element K and the electrically conductive member have a configuration stacked in the direction of facing of the first substrate and the second substrate.

[0067] Figure 2 is a cross-sectional structural view showing an embodiment (configuration B) of the π-type thermoelectric conversion module of the present application, and the π-type thermoelectric conversion module 11 is configured so that the thermoelectric conversion member A 4a including the thermoelectric conversion element M 4al and the heat backflow inhibiting member B 4b including a configuration in which the thermoelectric conversion element K 4bl and the electrically conductive member 4b2 are stacked are alternately and separately arranged between the facing pair of the first substrate 2a having the first electrode 3a and the second substrate 2b having the second electrode 3b, and the thermoelectric conversion member A 4a and the heat backflow inhibiting member B 4b are electrically connected in series via the first electrode 3a on the first substrate 2a and the second electrode 3b on the second substrate 2b.

[0068] Here, for example, the π-type thermoelectric conversion module 11 is configured so that the area of the upper and lower surfaces (not shown) of the thermoelectric conversion member A 4a including the thermoelectric conversion element M 4al which are bonded to the first electrode 3a side or the second electrode 3b side is larger than the area of the upper and lower surfaces (not shown) of the heat backflow inhibiting member B 4b including a configuration in which the thermoelectric conversion element K 4bl and the electrically conductive member 4b2 are stacked which are bonded to the first electrode 3a side or the second electrode 3b side.

[0069] <Electrically conductive member>

[0070] The electrically conductive member used in the present application is preferably used in a stacked state with the thermoelectric conversion element K. As the stacked body, for example, it can be a configuration in which the electrically conductive member and the thermoelectric conversion element K are each a single layer, a three-layer configuration in which the electrically conductive member is sandwiched by the thermoelectric conversion element K, or a configuration in which a plurality of them are alternately stacked.

[0071] The electrically conductive member can be formed of an electrically conductive material described later, or can be a thin film formed of a composition including the same.

[0072] As the electrically conductive material constituting the electrically conductive member, metal materials such as copper, silver, gold, platinum, nickel, aluminum, constantan, chromium, indium, iron, or alloys thereof, indium tin oxide (ITO), zinc oxide (ZnO), or the like can be exemplified.

[0073] Among them, from the viewpoint of thermoelectric performance, a material that easily reduces the electric resistance of the electrically conductive member and increases the thermal resistance is preferably used.

[0074] There are no particular limitations on the methods used to form conductive components or to laminate conductive components onto the thermoelectric conversion element K. Examples include: dry processes such as vacuum evaporation, sputtering, ion plating, etc. (PVD), thermal CVD, atomic layer deposition (ALD), etc. (CVD), or known methods such as screen printing, flexographic printing, gravure printing, spin coating, dip coating, mold coating, spray coating, bar coating, and blade coating. When forming a patterned coating of the composition, screen printing or slot die coating, which allows for easy pattern formation using a screen with the desired pattern, is preferred.

[0075] In addition, the patterning of conductive components can also be carried out through known physical or chemical processes, primarily photolithography, or by combining them.

[0076] Preferably, the height of the thermoelectric conversion element M in the thickness direction of the thermoelectric conversion component A is higher than the height of the thermoelectric conversion element K in the thickness direction of the thermal backflow suppression component B, which has a conductive component.

[0077] By making the height of thermoelectric conversion element M higher than the height of thermoelectric conversion element K, the resistance of thermoelectric conversion element K can be suppressed to a low level, ensuring sufficient current even if the area of ​​the surface of thermoelectric conversion element K opposite the electrode is small. Therefore, the effect of using thermoelectric conversion element K to prevent backflow of heat transfer caused by thermoelectric conversion component A and to ensure current flow becomes more significant.

[0078] From this perspective, the thickness of the conductive component is not particularly limited and can be appropriately adjusted according to the thickness of the thermoelectric conversion element K. For example, when the heat backflow suppression component B is composed of a conductive component and the thermoelectric conversion element K, each in a single layer, the ratio of the thickness of the thermoelectric conversion element K to the thickness of the conductive component is preferably 1:9 to 9:1, more preferably 2:8 to 8:2, and even more preferably 2:8 to 4:6.

[0079] The total area S of the surfaces of thermoelectric conversion component A that are in contact with the first and second electrodes. A S is the sum of the areas S of the surfaces of thermoelectric conversion member A that are in contact with the first and second electrodes. A The sum of the areas S of the surfaces of the thermal backflow suppression component B that are in contact with the first and second electrodes. B The ratio R[=S] A / (S A +S B As mentioned above.

[0080] The following S A1B1 and SA2B2 may be the same or different, and is preferably the same from the viewpoint of uniformity of the heat-absorbing surface. The S A1B1 is the sum of the areas S A1 of the surface side of the thermoelectric conversion member A 4a and the surface side of the conductive member 4b2 which are joined to the first electrode 3a and the second electrode 3b, respectively. B1 is the sum of the areas S A2B2 of the surface side of the thermoelectric conversion member A 4a and the surface side of the conductive member 4b2 which are joined to the first electrode 3a and the second electrode 3b, respectively. A2 is the sum of the areas S B2 of the surface side of the thermoelectric conversion member A 4a and the surface side of the conductive member 4b2 which are joined to the first electrode 3a and the second electrode 3b, respectively. A2B2 .

[0081] is the sum of the areas S A1 of the surface side of the thermoelectric conversion member A 4a and the surface side of the conductive member 4b2 which are joined to the first electrode 3a and the second electrode 3b, respectively. A2 may be the same or different, and is preferably the same.

[0082] is the sum of the areas S B1 of the surface side of the thermoelectric conversion member A 4a and the surface side of the conductive member 4b2 which are joined to the first electrode 3a and the second electrode 3b, respectively. B2 may be the same or different, and is preferably the same.

[0083] Figure 3 is a cross-sectional structural view showing an embodiment (configuration C) of an existing thermoelectric conversion module, and the thermoelectric conversion module 21 is a so-called single-leg-type thermoelectric conversion module which is configured so that the thermoelectric conversion member A 4a containing the thermoelectric conversion element M 4a1 and the conductive member 4b2 are alternately and separately arranged between the opposing pair of the first substrate 2a having the first electrode 3a and the second substrate 2b having the second electrode 3b, and the thermoelectric conversion member A 4a and the conductive member 4b2 are electrically connected in series via the first electrode 3a on the first substrate 2a and the second electrode 3b on the second substrate 2b.

[0084] Here, for example, the thermoelectric conversion member A 4a containing the thermoelectric conversion element M 4a1 is configured so that the areas of the upper and lower surfaces (not shown) thereof which are joined to the first electrode 3a side or the second electrode 3b side are larger than the areas of the upper and lower surfaces (not shown) of the conductive member 4b2 which are joined to the first electrode 3a side or the second electrode 3b side.

[0085] Figure 4is a cross-sectional structural view showing an embodiment (Configuration D) of the existing π-type thermoelectric conversion module. The π-type thermoelectric conversion module 31 is configured so that the thermoelectric conversion member A 4a including the thermoelectric conversion element M 4al and the thermoelectric conversion element K 4bl are alternately and separately arranged between the pair of opposing first substrate 2a having the first electrode 3a and the second substrate 2b having the second electrode 3b. Further, the thermoelectric conversion member A 4a including the thermoelectric conversion element M 4al and the thermoelectric conversion element K 4bl are electrically connected in series via the first electrode 3a on the first substrate 2a and the second electrode 3b on the second substrate 2b.

[0086] Here, for example, the π-type thermoelectric conversion module 31 is configured so that the area of the upper and lower surfaces (not shown) of the thermoelectric conversion member A 4a including the thermoelectric conversion element M 4al bonded to the first electrode 3a side or the second electrode 3b side is substantially the same as the area of the upper and lower surfaces (not shown) of the thermoelectric conversion element K 4bl bonded to the first electrode 3a side or the second electrode 3b side.

[0087] [Heat absorption amount]

[0088] The heat absorption amount was calculated by thermal simulation shown below.

[0089] (a) Heat absorption amount of P-type thermoelectric conversion element and N-type thermoelectric conversion element

[0090] The heat absorption amount Qc of the P-type thermoelectric conversion element and the N-type thermoelectric conversion element can be calculated by the following formula (1), respectively.

[0091] Q c = SeT c I-(λS / L)ΔT-(1 / 2)RI 2 (1)

[0092] Q c : Heat absorption amount of thermoelectric conversion element (W / m 2 )

[0093] Se: Seebeck coefficient (V / K)

[0094] I: Current value of thermoelectric conversion module (A)

[0095] T c : Temperature of heat absorption surface of thermoelectric conversion module (K)

[0096] T h : Temperature of heat release surface of thermoelectric conversion module (K)

[0097] ΔT: Temperature difference (T h -T c ) (K)

[0098] R: electric resistance value of thermoelectric conversion assembly (Ω)

[0099] λ: thermal conductivity of thermoelectric conversion element [W / (m-K)]

[0100] L: height of thermoelectric conversion element (m)

[0101] S: area of heat-absorbing surface side of thermoelectric conversion element which is bonded to the first and second electrodes (m 2 )

[0102] Note that, for the maximum heat absorption amount Q CMAX (W), the current value (A) of the thermoelectric conversion assembly can be taken as the maximum current value (A), and ΔT can be taken as 0 in the above formula (1) to calculate.

[0103] (b) heat transfer amount of conductive member

[0104] heat transfer amount Q A of conductive member can be calculated by the following formula (2).

[0105] Q A = -(λS / L)ΔT (2)

[0106] Q A : heat transfer amount (W / m 2 )

[0107] ΔT: temperature difference (T h -T c ) (K)

[0108] λ: thermal conductivity of conductive member [W / (m-K)]

[0109] L: height L of conductive member (m)

[0110] S: area of heat-absorbing surface side of conductive member which is bonded to the first and second electrodes (m 2 )

[0111] (c) total heat absorption amount

[0112] total heat absorption amount Q F can be calculated by the following formula (3).

[0113] Q F = Q c + Q A (3)

[0114] <Thermoelectric Conversion Element>

[0115] The thermoelectric conversion element M in the thermoelectric conversion member A and the thermoelectric conversion element K in the heat backflow suppressing member B used in the present application can be any of a thermoelectric conversion element formed of a thermoelectric semiconductor material and a thin film formed of a thermoelectric semiconductor composition, as long as a material having different carriers is combined.

[0116] From the viewpoints of flexibility, thinness, and thermoelectric properties, it is preferred that the thin film formed of a thermoelectric semiconductor composition containing a thermoelectric semiconductor material (hereinafter sometimes referred to as "thermoelectric semiconductor particles"), a resin, an ionic liquid, and one or both of inorganic ionic compounds.

[0117] (Thermoelectric Semiconductor Material)

[0118] The thermoelectric semiconductor material used in the thermoelectric conversion element M and the thermoelectric conversion element K is preferably pulverized to a given size using a pulverizer or the like and used as a thermoelectric semiconductor particle.

[0119] The particle diameter of the thermoelectric semiconductor particle is preferably from 10 nm to 100 μm.

[0120] The average particle diameter of the above thermoelectric semiconductor particle can be obtained by measurement with a laser diffraction particle size analyzer (manufactured by Malvern, Mastersizer 3000) as the median of the particle diameter distribution.

[0121] In the thermoelectric conversion element M and the thermoelectric conversion element K used in the present application, as a thermoelectric semiconductor material constituting a P-type thermoelectric conversion element and an N-type thermoelectric conversion element, for example, a bismuth-tellurium-based thermoelectric semiconductor material such as P-type bismuth telluride and N-type bismuth telluride; a telluride-based thermoelectric semiconductor material such as GeTe and PbTe; a bismuth-tellurium-based thermoelectric semiconductor material; a zinc-antimony-based thermoelectric semiconductor material such as ZnSb, Zn3Sb2, and Zn4Sb3; a silicon-germanium-based thermoelectric semiconductor material such as SiGe; a bismuth-selenium-based thermoelectric semiconductor material such as Bi2Se3; a silicide-based thermoelectric semiconductor material such as β-FeSi2, CrSi2, MnSi 1.73 , Mg2Si; an oxide-based thermoelectric semiconductor material; a Heusler alloy material such as FeVAl, FeVAlSi, FeVTiAl; a sulfide-based thermoelectric semiconductor material such as TiS2, and the like can be used.

[0122] The content of the thermoelectric semiconductor particle in the above thermoelectric semiconductor composition is preferably from 30 to 99% by mass. When the content of the thermoelectric semiconductor particle is within the above range, the Seebeck coefficient (absolute value of the Peltier coefficient) is large, and the decrease in the electrical conductivity can be suppressed, and only the thermal conductivity decreases, so that a film which exhibits high thermoelectric properties and has sufficient film strength and flexibility can be obtained, and thus is preferred.

[0123] In addition, the thermoelectric semiconductor particles are preferably subjected to annealing treatment (hereinafter sometimes referred to as "annealing treatment A"). By performing the annealing treatment A, the crystallinity of the thermoelectric semiconductor particles is improved, and further, since the surface oxide film of the thermoelectric semiconductor particles is removed, the Seebeck coefficient (absolute value of the Peltier coefficient) of the thermoelectric conversion element is increased, and it is possible to further improve the thermoelectric performance index.

[0124] (resin)

[0125] The resin used in the present application has an effect of physically bonding the thermoelectric semiconductor materials (thermoelectric semiconductor particles) to each other, and is capable of improving the flexibility of the thermoelectric conversion module and making it easy to form a thin film based on coating or the like.

[0126] As the resin, a heat-resistant resin or an adhesive resin is preferable.

[0127] In the case where the thermoelectric semiconductor particles are caused to grow crystals by performing annealing treatment or the like on a thin film formed of the thermoelectric semiconductor composition, in the case of a heat-resistant resin, each property such as mechanical strength and thermal conductivity as a resin is maintained without being impaired.

[0128] From the viewpoint of higher heat resistance and no adverse effect on the crystal growth of the thermoelectric semiconductor particles in the thin film, the above-mentioned heat-resistant resin is preferably a polyamide resin, a polyamide-imide resin, a polyimide resin, an epoxy resin, and from the viewpoint of excellent flexibility, a polyamide resin, a polyamide-imide resin, a polyimide resin is more preferable.

[0129] It is preferable that the decomposition temperature of the above-mentioned heat-resistant resin be 300°C or higher. When the decomposition temperature is in the above-mentioned range, as described later, even in the case where a thin film formed of the thermoelectric semiconductor composition is subjected to annealing treatment, the function as an adhesive is not lost, and the flexibility can be maintained.

[0130] The content of the above-mentioned heat-resistant resin in the above-mentioned thermoelectric semiconductor composition is 0.1 to 40 mass%. When the content of the above-mentioned heat-resistant resin is in the above-mentioned range, the function as an adhesive of the thermoelectric semiconductor material is exerted, and it is easy to form a thin film.

[0131] The adhesive resin is also easily peeled from a glass, alumina, silicon or the like substrate used at the time of manufacturing a chip of the thermoelectric conversion material after firing (annealing) treatment (corresponding to "annealing treatment B" described later, and the same applies hereinafter).

[0132] As the binder resin, a resin that decomposes by 90 mass% or more at the firing (annealing) temperature is meant. That is, when a resin that decomposes at a lower temperature than the above-described heat-resistant resin is used, the binder resin decomposes by firing, and thus the content of the binder resin that becomes an insulating component in the fired body decreases, the crystallization growth of the thermoelectric semiconductor particles in the thermoelectric semiconductor composition is promoted, and thus the voids in the thermoelectric conversion material layer can be reduced, and the filling rate can be improved.

[0133] Note that whether or not a resin decomposes by a given value (for example, 90 mass%) or more at the firing (annealing) temperature can be determined by measuring the mass reduction rate (a value obtained by dividing the mass before decomposition by the mass after decomposition) at the firing (annealing) temperature based on thermogravimetric analysis (TG).

[0134] As such a binder resin, a thermoplastic resin or a curable resin can be used. As the thermoplastic resin, for example, a polyolefin-based resin such as polyethylene, polypropylene, polyisobutylene, polymethylpentene, and the like; a polycarbonate; a thermoplastic polyester resin such as polyethylene terephthalate, polyethylene naphthalate, and the like; a polystyrene, an acrylonitrile-styrene copolymer, polyvinyl acetate, an ethylene-vinyl acetate copolymer, vinyl chloride, a polyvinylpyridine, a polyvinyl alcohol, a polyvinylpyrrolidone, and the like; a polyurethane; a cellulose derivative such as ethyl cellulose; and the like can be listed. As the curable resin, for example, a thermosetting resin, a photocurable resin can be listed. As the thermosetting resin, for example, an epoxy resin, a phenol resin, and the like can be listed. As the photocurable resin, for example, a photocurable acrylic resin, a photocurable urethane resin, a photocurable epoxy resin, and the like can be listed. These can be used alone or in combination with two or more.

[0135] The content of the binder resin in the thermoelectric semiconductor composition is 0.1 to 40 mass%.

[0136] (Ionic liquid)

[0137] The ionic liquid that can be contained in the thermoelectric semiconductor composition is a molten salt composed of a cation and an anion, and refers to a salt that can exist as a liquid in an arbitrary temperature range of -50°C or higher and lower than 400°C. The ionic liquid has the following characteristics: extremely low vapor pressure and non-volatility, excellent thermal stability and electrochemical stability, low viscosity, and high ionic conductivity, and thus can effectively suppress the reduction in electrical conductivity between thermoelectric semiconductor materials as an electrically conductive aid.

[0138] The ionic liquid can use a publicly known or commercially available ionic liquid. For example, an ionic liquid composed of the following cation component and the following anion component can be listed, the cation component is a pyridinium cation pyrimidine pyrazole pyrrolidine Piperidine Imidazole Nitrogen-containing cyclic cationic compounds and their derivatives; tetraalkylammonium ammonium cations and their derivatives; trialkyl tetraalkyl wait Cations and their derivatives; lithium cations and their derivatives, etc., wherein the anionic component is Cl. - ,Br - I - AlCl4 - Al2Cl7 - BF4 - PF6 - ClO4 - NO3 - CH3COO - CF3COO - CH3SO3 - CF3SO3 - (FSO2)2N - (CF3SO2)2N - (CF3SO2)3C - AsF6 - SbF6 - NbF6 - TaF6 - F(HF) n - (CN)2N - C4F9SO3 - (C2F5SO2)2N - C3F7COO - (CF3SO2)(CF3CO)N - wait.

[0139] The content of the ionic liquid in the thermoelectric semiconductor composition is preferably 0.01 to 50% by mass. When the content of the ionic liquid is within the above range, the decrease in conductivity can be effectively suppressed, thereby obtaining a film with high thermoelectric properties.

[0140] (Preparation method of thermoelectric semiconductor composition)

[0141] There are no particular limitations on the preparation method of the thermoelectric semiconductor composition. The thermoelectric semiconductor composition can be prepared by adding, for example, the above-mentioned thermoelectric semiconductor particles, the above-mentioned ionic liquid and the above-mentioned resin, as well as other additives and solvents as needed, by using known methods such as ultrasonic homogenizer, spiral stirrer, planetary stirrer, disperser, and mixing stirrer, and mixing and dispersing them.

[0142] Examples of solvents mentioned above include toluene, ethyl acetate, methyl ethyl ketone, alcohols, tetrahydrofuran, methylpyrrolidone, ethyl cellosolve, etc. These solvents can be used alone or in combination of two or more. The concentration of the solid components in the thermoelectric semiconductor composition is not particularly limited, as long as it is suitable for the viscosity of the composition for application.

[0143] The thermoelectric conversion element formed from the above-described thermoelectric semiconductor composition is not particularly limited. For example, it can be formed by coating the thermoelectric semiconductor composition onto a substrate such as glass, alumina, silicon, or a resin film, or onto a substrate on which the sacrificial layer described later is formed, obtaining a coating film, and then drying it. The thermoelectric conversion element is obtained by appropriately separating it from the substrate. By forming it in this way, a large number of thermoelectric conversion elements can be easily obtained at low cost. As the resin film, it can be a heat-resistant film, preferably a film formed from polyamide resin, polyamide-imide resin, or polyimide resin.

[0144] Methods for obtaining thermoelectric conversion elements by coating thermoelectric semiconductor compositions include well-known methods such as screen printing, flexographic printing, gravure printing, spin coating, dip coating, die coating, spray coating, bar coating, and scraping coating, without particular limitation. When forming a patterned film, screen printing and slot die coating, which can easily form patterns using a screen with the desired pattern, are preferred.

[0145] Next, the obtained coating film can be dried to form a thermoelectric conversion element. As a drying method, existing and known drying methods such as hot air drying, hot roller drying, and infrared irradiation can be used. The heating temperature is typically 80~150℃, and the heating time varies depending on the heating method, but is usually from a few seconds to tens of minutes.

[0146] Furthermore, when a solvent is used in the preparation of a thermoelectric semiconductor composition, there are no particular restrictions on the heating temperature, as long as it falls within a temperature range that can dry the solvent used.

[0147] From the perspective of suppressing the resistance of the thermoelectric conversion element to a low level, making it easier to increase the current flowing through the thermoelectric conversion element, and thus contributing to the increase of heat absorption of the thermoelectric conversion assembly, it is preferable that the thickness of the thermoelectric conversion element is thin, typically less than 2000 μm.

[0148] The thickness of the thermoelectric conversion element is preferably 10 to 1600 μm, more preferably 50 to 1400 μm, further preferably 100 to 1200 μm, and particularly preferably 400 to 1000 μm. By making the thickness of the thermoelectric conversion element equal to or greater than the above lower limit value, the increase in the heat generation amount of the electrode, the solder material layer, and the like that constitute the π-type thermoelectric conversion module can be suppressed, and the heat absorption amount of the thermoelectric conversion module can be increased.

[0149] The electrical resistance value of each thermoelectric conversion element M is preferably 30 (mΩ) or less. By being 30 (mΩ) or less, the current value per unit area of the thermoelectric conversion element is easily increased, and thus the heat absorption amount is increased to a desired range. The lower limit value of the electrical resistance value is not particularly limited, and is about 0.01 (mΩ) from the viewpoint of ease of manufacture. From this viewpoint, the electrical resistance value is preferably 0.01 to 30 (mΩ), more preferably 0.1 to 20 (mΩ), further preferably 1.0 to 17 (mΩ), and particularly preferably 6 to 13 (mΩ).

[0150] The electrical resistance value of each thermoelectric conversion element K is preferably 100 (mΩ) or less. By being 100 (mΩ) or less, the current value per unit area of the thermoelectric conversion element is easily increased, and thus the heat absorption amount is increased to a desired range. The lower limit value of the electrical resistance value is not particularly limited, and is about 0.1 (mΩ) from the viewpoint of ease of manufacture. From this viewpoint, the electrical resistance value is preferably 0.1 to 100 (mΩ), more preferably 1 to 60 (mΩ), further preferably 10 to 50 (mΩ), and particularly preferably 30 to 45 (mΩ).

[0151] The areas of the upper and lower surfaces of the thermoelectric conversion element M are each independently preferably 0.04 to 30 (mm 2 ), more preferably 0.30 to 10 (mm 2 ), further preferably 0.5 to 4 (mm 2 ), and particularly preferably 0.7 to 2 (mm 2 ).

[0152] On the other hand, the areas of the upper and lower surfaces of the thermoelectric conversion element K are each independently preferably 0.01 to 2 (mm 2 ), more preferably 0.04 to 1 (mm 2 ), further preferably 0.06 to 0.9 (mm 2 ), and particularly preferably 0.1 to 0.6 (mm 2 ).

[0153] The ratio of the area of the upper surface to the area of the lower surface of each of the thermoelectric conversion elements M, K is preferably 0.80 to 1.20, more preferably 0.90 to 1.10, and further preferably 0.99 to 1.01, independently.

[0154] When the area of the upper surface to the area of the lower surface of the chip of the thermoelectric conversion element and the ratio of the area of the upper surface to the area of the lower surface of the thermoelectric conversion element are within the range, the resistance value can be suppressed to a low level, and the heat absorption amount can be easily increased.

[0155] In the case where the upper and lower surfaces of the thermoelectric conversion elements M, K are rectangular (the overall shape is a rectangular parallelepiped or a cubic shape), the length of one side is preferably 0.2 to 10 mm, more preferably 0.5 to 5 mm, and further preferably 0.8 to 2 mm.

[0156] However, the length of at least one side of the upper and lower surfaces of the thermoelectric conversion element K is shorter than the length of the same portion of the thermoelectric conversion element M. For example, the length of at least one side is preferably 1 to 90% of the length of the same portion of the thermoelectric conversion element M, more preferably 5 to 60%, and particularly preferably 10 to 30%.

[0157] By setting the length of one side of the upper and lower surfaces of the thermoelectric conversion elements M, K and the ratio of the lengths of the respective one sides to the above range, a π-type thermoelectric conversion module having a high heat absorption amount can be manufactured with good accuracy.

[0158] For the thermoelectric conversion element which is a thin film formed of the thermoelectric semiconductor composition, it is preferable to further perform an annealing treatment (hereinafter sometimes referred to as "annealing treatment B"). By performing the annealing treatment B, the thermoelectric properties can be stabilized, and the thermoelectric semiconductor particles in the thin film can be subjected to crystal growth, and the thermoelectric properties can be further improved. The annealing treatment B is not particularly limited, and is usually performed in a non-active gas atmosphere such as nitrogen or argon, in a reducing gas atmosphere, or under vacuum conditions, and can be performed at 100 to 700°C for several minutes to several tens of hours, although depending on the heat resistance temperature and the like of the resin and the ionic compound used. In addition, in the annealing treatment B, the thermoelectric semiconductor composition can be pressed to increase the density of the thermoelectric semiconductor composition.

[0159] As the above-mentioned sacrificial layer, a resin such as polymethyl methacrylate or polystyrene, or a mold release agent such as a fluorine-based mold release agent or a silicone-based mold release agent can be used. When a sacrificial layer is used, the thermoelectric conversion element formed on a substrate such as glass can be easily peeled from the above-mentioned glass or the like after the annealing treatment B.

[0160] The formation of the sacrificial layer is not particularly limited, and can be performed by a known method such as a flexographic printing method or a spin coating method.

[0161] <Substrate>

[0162] As the substrate of the π-type thermoelectric conversion module of the present application, that is, as the first substrate and the second substrate, a plastic film, a ceramic substrate, or the like which does not affect the decrease in the electrical conductivity or the increase in the thermal conductivity of the thermoelectric conversion element is preferably used. From the viewpoint that the substrate does not undergo thermal deformation even when the thermoelectric conversion element is subjected to an annealing treatment and that the performance, heat resistance, and dimensional stability of the π-type thermoelectric conversion module are high, as the plastic film, a polyimide film, a polyamide film, a polyetherimide film, a polyaramid film, a polyamideimide film, a glass / epoxy sheet is preferably used.

[0163] From the viewpoint of the flexibility, heat resistance, and dimensional stability, the thickness of the plastic film used for the above-described substrate is preferably 1 to 1000 μm, more preferably 10 to 500 μm, and further preferably 20 to 100 μm. On the other hand, the thickness of the ceramic substrate is preferably 100 μm to 30 mm, more preferably 500 μm to 10 mm, and particularly preferably 1 to 5 mm.

[0164] <Electrode>

[0165] The metal material used as the electrode of the π-type thermoelectric conversion module of the present application is not particularly limited, and, for example, as the metal material of the first electrode and the second electrode, gold, nickel, aluminum, rhodium, platinum, chromium, palladium, stainless steel, molybdenum, or an alloy containing any of these metals, or the like can be exemplified.

[0166] In addition, a paste containing a solvent and a resin component in addition to the metal material can be used for the formation. In the case of using the paste, the solvent and the resin component are preferably removed by firing or the like. As the paste, a silver paste, an aluminum paste is preferably used.

[0167] The thickness of the layer of the above-described electrode is preferably 10 nm to 200 μm. When the thickness of the layer of the electrode is within the above-described range, the electrical conductivity is high and the resistance is low, and sufficient strength as the electrode can be obtained.

[0168] As the method of forming the electrode, a method of processing into a given pattern shape by a publicly known physical treatment or chemical treatment mainly using a photolithography method or a combination thereof, or a method of forming a pattern of the electrode by a screen printing method, a stencil printing method, an inkjet method, or the like can be exemplified.

[0169] As the method of forming the electrode which is not patterned, a vacuum deposition method, a sputtering method, an ion plating method, or the like PVD (Physical Vapor Deposition), or a thermal CVD, an atomic layer deposition (ALD), or the like CVD (Chemical Vapor Deposition), or a vacuum film formation method, or a dipping method, a spin coating method, a spray coating method, a gravure coating method, a die coating method, a blade coating method, or the like various coating, an electrodeposition method, a silver salt method, an electroplating method, an electroless plating method, a lamination of a metal foil, or the like can be appropriately selected depending on the metal material.

[0170] < solder material layer >

[0171] The solder material layer is used for joining the thermoelectric conversion element and the electrode.

[0172] As the solder material constituting the solder material layer, known materials such as Sn, Sn / Pb alloy, Sn / Ag alloy, Sn / Cu alloy, Sn / Sb alloy, Sn / In alloy, Sn / Zn alloy, Sn / In / Bi alloy, Sn / In / Bi / Zn alloy, Sn / Bi / Pb / Cd alloy, Sn / Bi / Pb alloy, Sn / Bi / Cd alloy, Bi / Pb alloy, Sn / Bi / Zn alloy, Sn / Bi alloy, Sn / Bi / Pb alloy, Sn / Pb / Cd alloy, Sn / Cd alloy, etc. can be listed.

[0173] As the commercially available solder material, the following products can be listed. For example, 42Sn / 58Bi alloy (manufactured by TANUMA MFG. CO., LTD., product name: SAM10-401-27), 41Sn / 58Bi / Ag alloy (manufactured by NIHON HANDA CO., LTD., product name: PF141-LT7HO), 96.5Sn3Ag0.5Cu alloy (manufactured by NIHON HANDA CO., LTD., product name: PF305-207BTO), etc. can be used.

[0174] The thickness of the solder material layer (after heating and cooling) is preferably 10 to 200 μm. When the thickness of the solder material layer is in this range, adhesion to the thermoelectric conversion element and the electrode is easily obtained.

[0175] As the method for applying the solder material on the substrate, known methods such as stencil printing, screen printing, dispensing method, etc. can be listed. The heating temperature varies depending on the solder material, resin film, etc. used, but is usually performed at 150 to 280°C for 3 to 20 minutes.

[0176] < heat releasing layer >

[0177] In the π-type thermoelectric conversion module of the present application, from the viewpoint of thermoelectric performance, it is preferable that a heat releasing layer is further provided on at least one side of the above-mentioned substrate.

[0178] The material used for the heat releasing layer is not particularly limited, and known materials can be used. It is preferable to be selected from gold, silver, copper, nickel, tin, iron, chromium, platinum, palladium, rhodium, iridium, ruthenium, osmium, indium, zinc, molybdenum, manganese, titanium, aluminum, stainless steel, and brass.

[0179] As a method of laminating the heat releasing layer, there is no particular limitation, and dry process such as vacuum evaporation method, sputtering method, ion plating method, or CVD (Chemical Vapor Deposition) such as thermal CVD, atomic layer deposition (ALD), or various coating methods such as dip coating method, spin coating method, spray coating method, gravure coating method, die coating method, blade coating method, wet process such as electrodeposition method, silver salt method, electroplating method, or electroless plating method can be exemplified.

[0180] In addition, the patterning of the heat releasing layer can be performed by a known physical treatment or chemical treatment mainly using photolithography, or a combination thereof.

[0181] The thermal conductivity of the heat releasing layer is each independently preferably 5 to 500 W / (m-K).

[0182] The thickness of the heat releasing layer can be appropriately determined from the viewpoint of thermoelectric performance, and is preferably 1 to 550 μm.

[0183] In addition, the calculated heat absorption per unit area of one unit (one pair of the thermoelectric conversion member A and the heat backflow suppressing member B) constituting the thermoelectric conversion module is preferably 1 to 30 W / cm 2 , more preferably 2.5 to 10 W / cm 2 , and particularly preferably 3.5 to 5.0 W / cm 2 When in this range, a thermoelectric conversion module having a high heat absorption and a thin film is easily obtained.

[0184] The total thickness of the π-type thermoelectric conversion module is preferably 300 μm to 20 mm.

[0185] When the total thickness of the π-type thermoelectric conversion module is in this range, the module resistance value of the thermoelectric conversion module is easily suppressed, and thus a π-type thermoelectric conversion module having a high cooling performance and a thin profile is obtained.

[0186] The π-type thermoelectric conversion module of the present application has an excellent cooling performance in which the backflow of heat is suppressed.

[0187] Examples

[0188] Next, the present application will be described in more detail by examples, but the present application is not limited to any of these examples.

[0189] The heat absorption of the π-type thermoelectric conversion module of the present application, the π-type thermoelectric conversion module of the related art, and the single-leg thermoelectric conversion module was evaluated by the following method.

[0190] (a) Evaluation of heat absorption

[0191] For the thermoelectric conversion modules of Examples 1 to 2 and Comparative Examples 1 to 2, the cooling performance (heat absorption amount per unit area) of each 1 unit (one pair of the thermoelectric conversion member A and the heat backflow suppression member B) was evaluated by the thermal simulation described above.

[0192] (Example 1)

[0193] For the π-type thermoelectric conversion module of the embodiment (configuration A) shown in FIG. 1, the heat absorption amount per unit area was evaluated by thermal simulation. Figure 1

[0194] First, the temperature of the cooling surface (heat absorption surface) was set to 50°C, and the temperature of the heat radiation surface was set to 70°C.

[0195] In addition, the physical property values of the thermoelectric conversion member A used, the physical property values of the heat backflow suppression member B, the current value of the thermoelectric conversion module, and the resistance value of the thermoelectric conversion module, and the like were set as follows.

[0196] (Thermoelectric Conversion Member A)

[0197] Thermoelectric Conversion Element M [P-type (BiSbTe-based)]

[0198] Dimensions: rectangular parallelepiped shape with 1 mm in length, 1 mm in width, and 1 mm in thickness

[0199] Se: Seebeck coefficient [183 x 10 -6 (V / K)]

[0200] I: Current value of the thermoelectric conversion module [1 (A)]

[0201] T c : Temperature of the heat absorption surface of the thermoelectric conversion module [273.15 + 50 (K)]

[0202] T h : Temperature of the heat radiation surface of the thermoelectric conversion module [273.15 + 70 (K)]

[0203] ΔT: Temperature difference (T h -T c ) [20 (K)]

[0204] R: Resistance value of one thermoelectric conversion element M [10.5 (mΩ)]

[0205] λ: Thermal conductivity of the thermoelectric conversion element M [1.02 [W / (m·K)]]

[0206] L: Height (thickness) of the thermoelectric conversion element M [1 x 10 -3 (m)]

[0207] ​S: The area of ​​the thermoelectric conversion element M on the side where it connects with the first and second electrodes [1×10] -6 (m 2 )]

[0208] (Thermal backflow suppression component B)

[0209] Thermoelectric conversion element K [N-type (BiTe series)]

[0210] Dimensions: A rectangular parallelepiped with a top and bottom surface dimensions of 1mm x 0.2mm and a thickness of 1mm.

[0211] Se: Seebeck coefficient [-132×10] -6 (V / K)]

[0212] I: Current value of the thermoelectric conversion component [1 (A)].

[0213] T c Temperature of the heat-absorbing surface of the thermoelectric conversion component [273.15 + 50 K]

[0214] T h Temperature of the heat-dissipating surface of the thermoelectric conversion component [273.15 + 70 K]

[0215] ΔT: Temperature difference (T) h -T c [20(K)]

[0216] R: The resistance value of a thermoelectric conversion element K [44.7 (mΩ)]

[0217] λ: Thermal conductivity of thermoelectric conversion element K [1.02 [W / (m·K)]]

[0218] L: Height (thickness) of thermoelectric conversion element K [1×10] -3 (m)]

[0219] S: The area of ​​the thermoelectric conversion element K on the side where it connects with the first and second electrodes [0.2 × 10⁻⁶]. -6 (m 2 )]

[0220] Conductive components: None

[0221] The spacing between thermoelectric conversion element M and thermoelectric conversion element K: 0.1mm

[0222] Therefore, the unit area comprising thermoelectric conversion element M, thermoelectric conversion element K, and their spacing is 1.3 mm². 2 .

[0223] (Example 2)

[0224] In Example 1, the change is as follows:Figure 2 The π-type thermoelectric conversion module of the embodiment (configuration B) shown was evaluated for heat absorption per unit area in the same manner as in Example 1, except that the thickness of the thermoelectric conversion element K [N-type (BiTe-based)] was set to 0.2 mm, and copper having the following dimensions and thermal conductivity was used as a new conductive member.

[0225] Dimensions: rectangular parallelepiped with 1 mm in length x 0.2 mm in width x 0.8 mm in thickness

[0226] λ: thermal conductivity [398 [W / (m-K)]]

[0227] (Note that the resistance value of the conductive member was calculated as 0 mΩ.)

[0228] R: resistance value of one thermoelectric conversion element K [8.9 (mΩ)]

[0229] (Comparative Example 1)

[0230] In Example 1, the following was changed Figure 3 The thermoelectric conversion module (single-leg type) of the embodiment (configuration C) shown was evaluated for heat absorption per unit area in the same manner as in Example 1, except that copper having the following dimensions and thermal conductivity was used instead of the thermoelectric conversion element K [N-type (BiTe-based)] as a conductive member in the heat backflow suppression member B.

[0231] Dimensions: rectangular parallelepiped with 1 mm in length x 0.2 mm in width x 1.0 mm in thickness

[0232] λ: thermal conductivity [398 [W / (m-K)]]

[0233] (Comparative Example 2)

[0234] In Example 1, the following was changed Figure 4 The existing π-type thermoelectric conversion module of the embodiment (configuration D) shown was evaluated for heat absorption per unit area in the same manner as in Example 1, except that the dimensions of the thermoelectric conversion element K [N-type (BiTe-based)] were set as follows.

[0235] Dimensions: rectangular parallelepiped with 1 mm in length x 1.0 mm in width x 1.0 mm in thickness

[0236] The simulation results of the heat absorption of the thermoelectric conversion modules obtained in Examples 1 and 2 (π-type) and Comparative Examples 1 (single-leg type) and 2 (π-type) are shown in Table 1.

[0237]

[0238] As is apparent from Table 1, the π-type thermoelectric conversion module of Examples 1 and 2 satisfying the limitation of the present application can obtain a high heat absorption amount, as compared with the existing single-leg-type thermoelectric conversion module of Comparative Example 1 and the existing π-type thermoelectric conversion module of Comparative Example 2 not satisfying the limitation of the present application.

[0239] Industrial applicability

[0240] The π-type thermoelectric conversion module according to the present application, since having an excellent cooling performance with the backflow of heat being suppressed, as a cooling use, temperature control of, for example, a CPU (Central Processing Unit) used in a smart phone, various computers, and the like, and an image sensor such as a CMOS (Complementary Metal Oxide Semiconductor), a CCD (Charge Coupled Device), and the like, and a sensor such as a MEMS (Micro Electro Mechanical Systems), other light-receiving elements, and the like, in the field of electronic devices, and the like, can be considered.

Claims

1. A π-type thermoelectric conversion assembly, wherein a thermoelectric conversion member A comprising a thermoelectric conversion element M and a heat backflow suppression member B comprising a thermoelectric conversion element K are alternately disposed between a first substrate having a first electrode and a second substrate having a second electrode, and the thermoelectric conversion member A and the heat backflow suppression member B are electrically connected in series via the first electrode on the first substrate and the second electrode on the second substrate. The charge carriers of the thermoelectric conversion element M and the thermoelectric conversion element K are different; one has holes and the other has electrons. The total area S of the surfaces of the thermoelectric conversion component A that are in contact with the first electrode and the second electrode A The area S of the surface of the thermal backflow suppression member B that is in contact with the first electrode and the second electrode is greater than the sum of the areas of the surfaces. B ,in, S A and S B The unit is m 2 .

2. The π-type thermoelectric conversion component according to claim 1, wherein, S A Compared to S A With S B The ratio of their sums, R = S A / (S A +S B The value is greater than 0.55 and less than 0.

95. The S A This refers to the sum of the areas of the surfaces of the thermoelectric conversion component A that are in contact with the first electrode and the second electrode. The S B It is the sum of the areas of the surfaces of the thermal backflow suppression component B that are in contact with the first electrode and the second electrode.

3. The π-type thermoelectric conversion assembly according to claim 1 or 2, wherein, The thermal backflow suppression component B includes the thermoelectric conversion element K and the conductive component, which are stacked in the opposite direction of the first substrate and the second substrate.

4. The π-type thermoelectric conversion component according to claim 3, wherein, The height of the thermoelectric conversion element M in the thickness direction of the thermoelectric conversion member A is higher than the height of the thermoelectric conversion element K in the thickness direction of the thermal backflow suppression member B having the conductive member.

Images