Thermoelectric Conversion Devices

Abstract

A thermoelectric conversion device 1 comprises an element body 11 including a plurality of laminated substrates 10, and a meander wiring 20 provided inside the element body 11 and having a laminated structure. The meander wiring 20 includes a thermoelectric material having an anomalous Nernst effect. A thermoelectric conversion device 2 comprises a core portion 30 and a winding 40 wound around the core portion 30. The winding 40 includes a thermoelectric material having an anomalous Nernst effect. A thermoelectric conversion device 3 comprises a plurality of substrates 10 and a meander wiring 20 provided on the main surface of each substrate 10. The meander wiring 20 includes a thermoelectric material having an anomalous Nernst effect. Adjacent substrates 10 are arranged at an angle larger than 0 degree and smaller than 180 degrees.

Description

[Technical field]

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

[0002] As an example of a thermoelectric conversion device that converts heat into electricity by using a temperature difference inside a material, Patent Document 1 discloses a film-shaped heat flux sensor. The heat flux sensor described in Patent Document 1 includes a flexible film-like insulating member having a first surface and a second surface opposite to the first surface, a plurality of first thermoelectric members arranged inside the insulating member and made of a first thermoelectric material, a plurality of second thermoelectric members arranged inside the insulating member and made of a second thermoelectric material different from the first thermoelectric material and arranged alternately with the plurality of first thermoelectric members, a plurality of first conductor patterns arranged on the first surface side with respect to the plurality of first thermoelectric members and the plurality of second thermoelectric members and connecting first thermoelectric members and second thermoelectric members that are arranged adjacent to each other among the plurality of first thermoelectric members and the plurality of second thermoelectric members, and a plurality of second conductor patterns arranged on the second surface side with respect to the plurality of first thermoelectric members and the plurality of second thermoelectric members and connecting first thermoelectric members and second thermoelectric members that are arranged adjacent to each other among the plurality of first thermoelectric members and the plurality of second thermoelectric members. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Patent No. 6658572 Summary of the Invention [Problem to be solved by the invention]

[0004] The heat flux sensor described in Patent Document 1 is installed on the measurement surface of the object to be measured with one of the first surface and the second surface in contact with the measurement surface of the object to be measured. A heat flow passes through the heat flux sensor in a direction from one of the first surface and the second surface of the heat flux sensor to the other. At this time, a temperature difference occurs between the first surface side and the second surface side of the heat flux sensor. That is, a temperature difference occurs between one side and the other side of each of the first thermoelectric member and the second thermoelectric member connected to each other. As a result, a thermoelectromotive force is generated in the first thermoelectric member and the second thermoelectric member by the Seebeck effect. The heat flux sensor described in Patent Document 1 outputs this thermoelectromotive force, specifically, a voltage, as a sensor signal.

[0005] However, the heat flux sensor described in Patent Document 1 has a problem in that the electromotive force relative to the temperature difference per installation area is small, and therefore is not sufficient for applications requiring a small installation area.

[0006] The present invention has been made to solve the above problems, and has an object to provide a thermoelectric conversion device that can obtain a sufficient electromotive voltage per unit installation area even when the temperature difference is small. [Means for solving the problem]

[0007] In a first aspect, a thermoelectric conversion device of the present invention includes an element body including a plurality of stacked substrates, and a meander wiring having a stacked structure provided inside the element body. The meander wiring includes a thermoelectric material having the anomalous Nernst effect.

[0008] In a second aspect, a thermoelectric conversion device of the present invention includes a core portion and a winding wound around the core portion, the winding including a thermoelectric material having the anomalous Nernst effect.

[0009] In a third aspect, the thermoelectric conversion device of the present invention includes a plurality of substrates and meandering wiring provided on a main surface of each of the substrates. The meandering wiring includes a thermoelectric material having the anomalous Nernst effect. The adjacent substrates are disposed at an angle greater than 0 degrees and less than 180 degrees. Effect of the Invention

[0010] According to the present invention, it is possible to provide a thermoelectric conversion device that can obtain a sufficient electromotive force per unit installation area even when the temperature difference is small. [Brief description of the drawings]

[0011] [Figure 1] FIG. 1 is a perspective view that illustrates an example of a thermoelectric conversion device according to a first embodiment of the present invention. [Diagram 2] FIG. 2 is an exploded perspective view of the thermoelectric conversion device shown in FIG. [Diagram 3] FIG. 3 is a cross-sectional view of the thermoelectric conversion device shown in FIG. 2 taken along line III-III. [Figure 4] FIG. 4 is an exploded perspective view illustrating a first modified example of the thermoelectric conversion device according to the first embodiment of the present invention. [Diagram 5] FIG. 5 is an exploded perspective view that illustrates a second modified example of the thermoelectric conversion device according to the first embodiment of the present invention. [Figure 6] FIG. 6 is an exploded perspective view that illustrates a schematic diagram of a third modified example of the thermoelectric conversion device according to the first embodiment of the present invention. [Figure 7] FIG. 7 is a perspective view that illustrates an example of a thermoelectric conversion device according to the first embodiment of the present invention in the form of a chip. [Figure 8] FIG. 8 is an enlarged perspective view of a portion enclosed by a dashed line in FIG. [Figure 9] FIG. 9 is a perspective view that illustrates an example of the thermoelectric conversion device illustrated in FIG. 7 in a state in which no via conductors are provided. [Figure 10] FIG. 10 is a perspective view that illustrates a schematic diagram of another example of the thermoelectric conversion device according to the first embodiment of the present invention in the form of a chip. [Figure 11] FIG. 11 is a perspective view that illustrates an example of a state in which the thermoelectric conversion device illustrated in FIG. 7 or FIG. 10 is separated into individual pieces. [Figure 12]FIG. 12 is an exploded perspective view illustrating a schematic diagram of a fourth modified example of the thermoelectric conversion device according to the first embodiment of the present invention. [Figure 13] FIG. 13 is an exploded perspective view illustrating a schematic diagram of a fifth modified example of the thermoelectric conversion device according to the first embodiment of the present invention. [Figure 14] FIG. 14 is an exploded perspective view illustrating a sixth modified example of the thermoelectric conversion device according to the first embodiment of the present invention. [Figure 15] FIG. 15 is a perspective view that illustrates an example of a thermoelectric conversion device according to the second embodiment of the present invention. [Figure 16] FIG. 16 is a cross-sectional view taken along line XVI-XVI of the thermoelectric conversion device shown in FIG. [Figure 17] FIG. 17 is a perspective view that illustrates an example of a thermoelectric conversion device according to the third embodiment of the present invention. [Figure 18] FIG. 18 is an exploded perspective view of the thermoelectric conversion device shown in FIG. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0012] The thermoelectric conversion device of the present invention will be described below. However, the present invention is not limited to the following configurations, and can be modified as appropriate within the scope of the present invention. Note that the present invention also includes a combination of two or more of the individual desirable configurations described below.

[0013] In the thermoelectric conversion device of the present invention, the total length of the wiring or windings containing the thermoelectric material can be increased, and therefore the electromotive voltage caused by the temperature gradient can be increased.

[0014] The thermoelectric conversion device of the present invention is, for example, a chip component. By forming the thermoelectric conversion device into a chip structure, the thermoelectric conversion device can be mounted on an electronic substrate by soldering or the like.

[0015] The following embodiments are merely examples, and it goes without saying that partial replacement or combination of the configurations shown in the different embodiments is possible. From the second embodiment onwards, a description of the matters common to the first embodiment will be omitted, and only the differences will be described. In particular, similar effects due to similar configurations will not be mentioned in each embodiment.

[0016] The drawings shown below are schematic diagrams, and the dimensions, aspect ratio, and scale may differ from those of the actual product.

[0017] [First embodiment] A thermoelectric conversion device according to a first embodiment of the present invention includes an element body including a plurality of stacked substrates, and meander wiring having a stacked structure provided inside the element body. The meander wiring includes a thermoelectric material having the anomalous Nernst effect.

[0018] Fig. 1 is a perspective view showing a schematic example of a thermoelectric conversion device according to a first embodiment of the present invention. Fig. 2 is an exploded perspective view of the thermoelectric conversion device shown in Fig. 1. Fig. 3 is a cross-sectional view taken along line III-III of the thermoelectric conversion device shown in Fig. 2. External electrodes are omitted in Figs. 2 and 3.

[0019] The thermoelectric conversion device 1 shown in Fig. 1 is a chip component. As shown in Fig. 2 and Fig. 3, the thermoelectric conversion device 1 includes an element body 11 including a plurality of stacked substrates 10, and meander wiring 20 having a stacked structure provided inside the element body 11. As shown in Fig. 1, the external shape of the thermoelectric conversion device 1 is, for example, a polygonal prism such as a rectangular parallelepiped.

[0020] 2 and 3, a plurality of substrates 10 are stacked in the z-axis direction to form an element body 11. The element body 11 may include a substrate 10 that is not provided with meander wiring 20. The number of substrates 10 on which meander wiring 20 is provided is not particularly limited, but is, for example, 2 or more and 100 or less.

[0021] In this specification, the meander wiring means a wiring that extends in one direction while meandering. The shape of the meander wiring may have sharp corners or may have chamfered corners.

[0022] In the example shown in Fig. 2, the meander wiring 20 is provided on the main surface of each substrate 10 and extends in the x-axis direction while meandering. As shown in Fig. 2, the meander wiring 20 is preferably provided on the main surface in the positive direction among the main surfaces of each substrate 10 that face the z-axis direction. The shape of the meander wiring 20 in a plan view may be the same or different between the substrates 10.

[0023] The meander wiring 20 includes a thermoelectric material that has the anomalous Nernst effect. The anomalous Nernst effect is a phenomenon in which, when a heat flow is caused to flow through a magnetized magnetic body, a voltage is generated in a direction (cross product direction) perpendicular to both the magnetization direction and the heat flow direction of the magnetic body.

[0024] In order to control the magnetization direction and increase the electromotive voltage, it is preferable that the meander wiring 20 has first wiring 21 made of a thermoelectric material and second wiring 22 made of a conductor arranged alternately on the main surface of each substrate 10, as shown in Fig. 2. Note that the meander wiring 20 may be composed of only the first wiring 21 made of a thermoelectric material.

[0025] The thermoelectric material constituting the first wiring 21 is, for example, Fe. 3 Sn, Fe 3 Al, Fe 3 Ga, Fe 3 Ge, Co 2 MnGa,Co 2 MnAl, Co 2 MnIn, Mn 3 Ga, Mn 3 Sn, Mn 3 Ge, Fe 2 NiGa, CoTiSb, COVSb, CoCrSb, CoMnSb, TiGa 2 Mn, etc.

[0026] Examples of conductors that form the second wiring 22 include Ag, Cu, Au, Ni, and Pt.

[0027] 2, the meander wiring 20 has a layered structure in the z-axis direction, and is connected between adjacent substrates 10 in the layering direction (z-axis direction in FIG. 2). Specifically, the meander wiring 20 between each substrate 10 is electrically connected through via conductors 23. Therefore, the meander wiring 20 extends in the main surface direction of the substrate 10, and has a layered structure in the layering direction of the substrate 10.

[0028] The meandering wiring 20 containing a thermoelectric material having the anomalous Nernst effect is connected between the substrates 10, so that the total length of the wiring containing the thermoelectric material can be increased. Therefore, even if the temperature difference is small, a sufficient electromotive voltage per unit installation area can be obtained.

[0029] 2, if all of first wiring 21 made of thermoelectric material is magnetized in the positive direction of the x-axis, when a heat flow occurs in the negative direction of the z-axis, a temperature difference occurs in the negative direction of the z-axis. As a result, a voltage is generated in first wiring 21 made of thermoelectric material in the cross product direction (i.e., the positive direction of the y-axis) perpendicular to the magnetization direction (positive direction of the x-axis) and the heat flow direction (negative direction of the z-axis) due to the anomalous Nernst effect.

[0030] Furthermore, by forming the meander wiring 20 into a stacked structure and shaping it into a chip shape, heat dissipation from the side walls increases and the temperature difference increases, resulting in an increase in the electromotive force at the time of thermal equilibrium in the lower layers.

[0031] As shown in FIG. 1, external electrodes 24 and 25 electrically connected to the meander wiring 20 are preferably provided on the surface of the element body 11 .

[0032] The material constituting the substrate 10 is not particularly limited, but a ceramic material having low thermal conductivity and low electrical conductivity is preferable. Examples of the ceramic material constituting the substrate 10 include aluminum nitride, boron nitride, silicon carbide, alumina, spinel oxide, and perovskite oxide. The material constituting the substrate 10 may be a ceramic material, a glass material, or a resin material. When the thermoelectric material and the substrate 10 are simultaneously fired, a low-temperature co-fired ceramic material is preferable in order not to change the ordered phase of the thermoelectric material. Examples of the low-temperature co-fired ceramic material include a composite material containing borosilicate glass and alumina. From the viewpoint of passing a large heat flow through the meander wiring 20 to generate a high electromotive force, it is preferable that the thermal conductivity of the ceramic material constituting the substrate 10 is low. However, when measuring a change in instantaneous heat flux, it is preferable that the thermal conductivity of the ceramic material constituting the substrate 10 is high from the viewpoint of passing a heat flow quickly through the thermoelectric conversion device 1. From the viewpoint of suppressing electrical short circuits between the meander wirings 20, it is preferable that the electrical conductivity of the ceramic material constituting the substrate 10 is low.

[0033] The material constituting the substrate 10 may include a material having a resistance temperature coefficient. For example, when the substrate 10 includes a material having a negative resistance temperature coefficient (NTC), an internal conductor for temperature detection is formed inside the chip component, so that the ambient temperature and heat flux can be measured simultaneously.

[0034] In the thermoelectric conversion device according to the first embodiment of the present invention, from the viewpoint of increasing the electromotive force, it is preferable that a magnet is arranged on one end face of the chip component. In this case, it is more preferable that another magnet with the same magnetic pole is arranged on the end face opposite to the end face on which the magnet is arranged. For example, in the thermoelectric conversion device 1 shown in Figs. 1 to 3, it is preferable that a magnet is arranged on one of the end faces facing each other in the x-axis direction, and it is more preferable that another magnet with the same magnetic pole is arranged on the other end face.

[0035] When a magnet is disposed on an end face of the chip component, the direction of the magnetic field generated by the magnet is preferably perpendicular to the direction of the current flowing through the first wiring and the direction of the heat flow. For example, in the thermoelectric conversion device 1 shown in Figures 1 to 3, it is preferable to generate a magnetic field in the x-axis direction.

[0036] In the thermoelectric conversion device according to the first embodiment of the present invention, from the viewpoint of increasing the temperature gradient and increasing the electromotive voltage, it is preferable that a highly thermally conductive member such as a heat dissipation sheet (also simply referred to as a thermally conductive member) is disposed on at least one end face of the chip component. For example, in the thermoelectric conversion device 1 shown in Figs. 1 to 3, from the viewpoint of promoting heat dissipation from the thermoelectric conversion device 1 to the outside to increase the temperature gradient and increase the thermoelectromotive voltage, it is preferable that a highly thermally conductive member is disposed on the end face (top face) facing the positive direction among the end faces facing in the z-axis direction. On the other hand, from the viewpoint of promoting the heat flow from the heat source to the thermoelectric conversion device 1, it is preferable that a highly thermally conductive member is disposed on the end face (bottom face) facing the negative direction among the end faces facing in the z-axis direction.

[0037] In the thermoelectric conversion device according to the first embodiment of the present invention, from the viewpoint of increasing heat dissipation and increasing electromotive voltage, it is preferable that at least one end face of the chip component has irregularities. For example, in the thermoelectric conversion device 1 shown in Fig. 1 to Fig. 3, it is preferable that, among the end faces facing each other in the z-axis direction, the end face (top face) facing in the positive direction has irregularities.

[0038] The thermoelectric conversion device according to the first embodiment of the present invention may include a plurality of meandering wirings extending in different directions between adjacent substrates in the stacking direction, in which case electromotive force can be obtained from heat fluxes in a plurality of directions.

[0039] FIG. 4 is an exploded perspective view illustrating a first modified example of the thermoelectric conversion device according to the first embodiment of the present invention.

[0040] In the thermoelectric conversion device 1A shown in FIG. 4, the meander wiring 20A includes wiring that meanders and extends in the x-axis direction, and wiring that meanders and extends in the y-axis direction.

[0041] For example, in FIG. 4, when all of the first wiring 21 made of a thermoelectric material is magnetized in the negative direction of the z-axis, an electromotive voltage can be obtained from heat flux in two directions, the x-axis direction and the y-axis direction.

[0042] FIG. 5 is an exploded perspective view that illustrates a second modified example of the thermoelectric conversion device according to the first embodiment of the present invention.

[0043] In the thermoelectric conversion device 1B shown in Fig. 5, a plurality of substrates 10 are stacked in the z-axis direction to form an element body 11, similar to the thermoelectric conversion device 1 shown in Fig. 2. However, unlike the thermoelectric conversion device 1 shown in Fig. 2, the meander wiring 20B extends in the z-axis direction while meandering.

[0044] 5, meander wiring 20B is formed by alternately stacking substrates 10 having first wiring 21 made of a thermoelectric material provided on their main surfaces and substrates 10 having second wiring 22 made of a conductor provided on their main surfaces in the stacking direction of substrate 10 (z-axis direction in FIG. 5). Meander wiring 20B is electrically connected through via conductors 23 between substrates 10 adjacent to each other in the z-axis direction.

[0045] Furthermore, the meander wiring 20B has a layered structure in the x-axis direction. The meander wirings 20 adjacent to each other in the x-axis direction are electrically connected via the second wiring 22. Therefore, the meander wiring 20B extends in the layered direction of the substrate 10 and has a layered structure in the main surface direction of the substrate 10.

[0046] For example, in FIG. 5, when the magnetization direction of the first wiring 21 made of a thermoelectric material is denoted by M and the direction of heat flow is denoted by Q, a current flows in the direction indicated by I.

[0047] In the thermoelectric conversion device 1B shown in Fig. 5, unlike the thermoelectric conversion device 1 shown in Fig. 2, the first wiring 21 and the second wiring 22 are separately provided on the main surface of another substrate 10. Therefore, by thinning the second wiring 22, the total thickness of the chip component can be reduced without reducing the sensitivity. For example, by using a material having a lower resistivity than the thermoelectric material forming the first wiring 21 as the conductor forming the second wiring 22, it is possible to form the second wiring 22 thin.

[0048] FIG. 6 is an exploded perspective view that illustrates a schematic diagram of a third modified example of the thermoelectric conversion device according to the first embodiment of the present invention.

[0049] The thermoelectric conversion device 1C shown in Fig. 6 has a common configuration with the thermoelectric conversion device 1B shown in Fig. 5, except that the meander wiring 20C is composed only of the first wiring 21 made of a thermoelectric material. By controlling the magnetization direction of the first wiring 21 according to the direction of current flow as in Fig. 6, the thermoelectric material can be made longer, and therefore the electromotive voltage can be increased.

[0050] Fig. 7 is a perspective view showing a typical example of a thermoelectric conversion device according to the first embodiment of the present invention in the form of a chip, and Fig. 8 is an enlarged perspective view of a portion enclosed by a dashed line in Fig. 7.

[0051] The thermoelectric conversion device 1D shown in Fig. 7 is a chip-like representation of the thermoelectric conversion device 1B shown in Fig. 5. As shown in Fig. 7 and Fig. 8, the meander wiring 20D is electrically connected through the via conductors 23 between the substrates 10 adjacent to each other in the z-axis direction.

[0052] FIG. 9 is a perspective view that illustrates an example of the thermoelectric conversion device illustrated in FIG. 7 in a state in which no via conductors are provided.

[0053] 9, a first wiring 21 and a second wiring 22 adjacent to each other in the z-axis direction may be directly connected to each other without using a via conductor 23. Such a structure can be produced by, for example, pressing.

[0054] In a thermoelectric conversion device 1D shown in FIG. 7, similarly to the thermoelectric conversion device 1C shown in FIG. 6, the meander wiring 20D may be formed only from the first wiring 21 made of a thermoelectric material.

[0055] FIG. 10 is a perspective view that illustrates a schematic diagram of another example of the thermoelectric conversion device according to the first embodiment of the present invention in the form of a chip.

[0056] In the thermoelectric conversion device 1D shown in Fig. 7, the heat flow is in the z-axis direction, but the heat flow may be in the y-axis direction as in the thermoelectric conversion device 1E shown in Fig. 10. In the thermoelectric conversion device 1E shown in Fig. 10, the direction Q of the heat flow can be changed from the z-axis direction to the y-axis direction by appropriately changing the magnetization direction M of the first wiring 21 included in the meander wiring 20E.

[0057] FIG. 11 is a perspective view that illustrates an example of a state in which the thermoelectric conversion device illustrated in FIG. 7 or FIG. 10 is separated into individual pieces.

[0058] As shown in FIG. 11, the thermoelectric conversion device 1D shown in FIG. 7 or the thermoelectric conversion device 1E shown in FIG. 10 may be cut with a dicer or the like to be in an individual piece.

[0059] FIG. 12 is an exploded perspective view illustrating a schematic diagram of a fourth modified example of the thermoelectric conversion device according to the first embodiment of the present invention.

[0060] In the thermoelectric conversion device 1F shown in Fig. 12, a plurality of substrates 10 are stacked in the z-axis direction to form an element body 11, similar to the thermoelectric conversion device 1 shown in Fig. 2. However, unlike the thermoelectric conversion device 1 shown in Fig. 2, the meander wiring 20F extends in the x-axis direction while meandering between the substrates 10 adjacent in the stacking direction (the z-axis direction in Fig. 12).

[0061] 12, meander wiring 20F is formed by alternately stacking substrates 10 having first wiring 21 made of a thermoelectric material provided on their main surfaces and substrates 10 having second wiring 22 made of a conductor provided on their main surfaces in the stacking direction of substrate 10 (z-axis direction in FIG. 12). Meander wiring 20F is electrically connected through via conductors 23 between substrates 10 adjacent to each other in the z-axis direction.

[0062] Furthermore, the meander wiring 20F has a layered structure in the z-axis direction. Between the substrates 10 adjacent in the z-axis direction, the meander wiring 20F is electrically connected through the via conductors 23. Therefore, the meander wiring 20F extends in the main surface direction of the substrate 10 and has a layered structure in the layering direction of the substrate 10.

[0063] For example, in FIG. 12, when the magnetization direction of the first wiring 21 made of a thermoelectric material is denoted by M and the direction of heat flow is denoted by Q, a current flows in the direction indicated by I.

[0064] In the thermoelectric conversion device 1F shown in Fig. 12, the first wiring 21 and the second wiring 22 are provided separately on the main surface of another substrate 10, similarly to the thermoelectric conversion device 1B shown in Fig. 5. Therefore, by thinning the second wiring 22, the total thickness of the chip component can be reduced without reducing the sensitivity. Moreover, in the thermoelectric conversion device 1F shown in Fig. 12, the second wiring 22 provided in the bottom layer in the thermoelectric conversion device 1B shown in Fig. 5 is no longer necessary, and the total thickness of the chip component can be further reduced accordingly.

[0065] FIG. 13 is an exploded perspective view illustrating a schematic diagram of a fifth modified example of the thermoelectric conversion device according to the first embodiment of the present invention.

[0066] A thermoelectric conversion device 1G shown in FIG. 13 has a common configuration with the thermoelectric conversion device 1F shown in FIG. 12, except that a meander wiring 20G is composed only of a first wiring 21 made of a thermoelectric material.

[0067] FIG. 14 is an exploded perspective view illustrating a sixth modified example of the thermoelectric conversion device according to the first embodiment of the present invention.

[0068] In the thermoelectric conversion device 1H shown in Fig. 14, a plurality of substrates 10 are stacked in the x-axis direction to form an element body 11. The meander wiring 20H has a stacked structure in the x-axis direction. Specifically, the meander wiring 20H is configured in a coil shape. The coil axis of the meander wiring 20H extends in the x-axis direction.

[0069] The meander wiring 20H is preferably configured such that first wirings 21 made of a thermoelectric material and second wirings 22 made of a conductor are alternately arranged as shown in Fig. 14. Note that the meander wiring 20H may be configured only with the first wirings 21 made of a thermoelectric material.

[0070] The thermoelectric conversion device 1H shown in FIG. 14 can be fabricated using a conventional manufacturing process for a multilayer inductor component.

[0071] As described above, in the thermoelectric conversion device according to the first embodiment of the present invention, the meander wiring 20, etc. may include a first wiring 21 made of a thermoelectric material and a second wiring 22 made of a conductor, or may include only the first wiring 21 made of a thermoelectric material.

[0072] In the thermoelectric conversion device according to the first embodiment of the present invention, the width of the first wiring 21 included in the meander wiring 20 etc. is preferably 50 nm or more, more preferably 1 μm or more, and even more preferably 20 μm or more, from the viewpoints of reducing wiring resistance, preventing disconnection or short circuit, etc. On the other hand, from the viewpoint of increasing the wiring density and increasing the total wiring length, the width of the first wiring 21 is preferably 5 mm or less, more preferably 500 μm or less, and even more preferably 200 μm or less.

[0073] In the thermoelectric conversion device according to the first embodiment of the present invention, the thickness of the first wiring 21 included in the meander wiring 20, etc. is preferably 50 nm or more, more preferably 1 μm or more, and even more preferably 20 μm or more, from the viewpoint of reducing wiring resistance, etc. Also, from the viewpoint of promoting heat dissipation from the side walls and increasing the temperature difference, it is preferable that the first wiring 21 is thick. On the other hand, if the first wiring 21 becomes too thick, it becomes difficult to increase the wiring density. Therefore, the thickness of the first wiring 21 is preferably 5 mm or less, more preferably 500 μm or less, and even more preferably 200 μm or less.

[0074] In the thermoelectric conversion device according to the first embodiment of the present invention, the aspect ratio represented by the thickness of the first wiring 21 / the width of the first wiring 21 is preferably equal to or less than 3. If the aspect ratio is greater than 3, it becomes difficult to form the wiring. On the other hand, the lower limit of the aspect ratio represented by the thickness of the first wiring 21 / the width of the first wiring 21 is not particularly limited, but the aspect ratio is, for example, equal to or greater than 0.2.

[0075] In the thermoelectric conversion device according to the first embodiment of the present invention, when the meander wiring 20 or the like includes the second wiring 22, the width of the second wiring 22 may be the same as the width of the first wiring 21, or may be smaller than the width of the first wiring 21 from the viewpoint of causing a larger heat flow through the first wiring 21 to generate a high electromotive voltage, or may be larger than the width of the first wiring 21 from the viewpoint of reducing electrical resistance. The thickness of the second wiring 22 may be the same as the thickness of the first wiring 21, or may be smaller than the thickness of the first wiring 21 from the viewpoint of causing a larger heat flow through the first wiring 21 to generate a high electromotive voltage, or may be larger than the thickness of the first wiring 21 from the viewpoint of reducing electrical resistance. Furthermore, the aspect ratio represented by the thickness of the second wiring 22 / the width of the second wiring 22 may be the same as the aspect ratio of the first wiring 21, or may be smaller than the aspect ratio of the first wiring 21, or may be larger than the aspect ratio of the first wiring 21.

[0076] [Second embodiment] A thermoelectric conversion device according to a second embodiment of the present invention includes a core portion and a winding wound around the core portion. The winding contains a thermoelectric material having the anomalous Nernst effect.

[0077] Fig. 15 is a perspective view showing an example of a thermoelectric conversion device according to a second embodiment of the present invention, and Fig. 16 is a cross-sectional view taken along line XVI-XVI of the thermoelectric conversion device shown in Fig. 15.

[0078] The thermoelectric conversion device 2 shown in Fig. 15 is a chip component. As shown in Figs. 15 and 16, the thermoelectric conversion device 2 includes a winding core 30 and a winding 40 wound around the winding core 30. As shown in Figs. 15 and 16, the shape of the winding core 30 is, for example, a drum type. The shape of the winding core 30 may have a convex portion in the center. The shape of the winding 40 may be a wire shape or a sheet shape.

[0079] The winding 40 includes a thermoelectric material having the anomalous Nernst effect. The winding 40 may be composed only of a wire or sheet made of a thermoelectric material. The surface of the winding 40 is preferably covered with an insulating material. The number of turns of the winding 40 is not particularly limited.

[0080] The total length of the wiring including the thermoelectric material can be increased by winding 40 including the thermoelectric material having the anomalous Nernst effect around the winding core 30. Therefore, even if the temperature difference is small, a sufficient electromotive voltage per unit installation area can be obtained.

[0081] For example, in Figures 15 and 16, when the winding 40 is magnetized in the negative direction of the z-axis, a heat flow flows in a direction perpendicular to the z-axis, and a temperature difference occurs from the inside to the outside of the winding core portion 30, a voltage is generated in the cross product direction perpendicular to the magnetization direction and the heat flow direction.

[0082] The thermoelectric material constituting the winding 40 is, for example, Fe. 3 Sn, Fe 3 Al, Fe 3 Ga, Fe 3 Ge, Co2 MnGa,Co 2 MnAl, Co 2 MnIn, Mn 3 Ga, Mn 3 Sn, Mn 3 Ge, Fe 2 NiGa, CoTiSb, COVSb, CoCrSb, CoMnSb, TiGa 2 Mn, etc.

[0083] An example of the insulating material that covers the surface of the winding 40 is an insulating resin such as polyimide.

[0084] One end of the winding 40 is connected to an electrode 41, and the other end is connected to an electrode .

[0085] The material constituting the winding core 30 is not particularly limited, but a ceramic material having high thermal conductivity and low electrical conductivity is preferable. Examples of the ceramic material constituting the winding core 30 include aluminum nitride, boron nitride, silicon carbide, alumina, spinel oxide, and perovskite oxide. The material constituting the winding core 30 may be a ceramic material, a glass material, or a resin material. When the thermoelectric material and the substrate 10 are simultaneously fired, a low-temperature co-fired ceramic material is preferable in order not to change the ordered phase of the thermoelectric material. Examples of the low-temperature co-fired ceramic material include a composite material containing borosilicate glass and alumina.

[0086] The material constituting the winding core 30 may include a material having a temperature coefficient of resistance. For example, when the winding core 30 includes an NTC material, an internal conductor for temperature detection is formed inside the chip component, so that the ambient temperature and heat flux can be measured simultaneously.

[0087] In the thermoelectric conversion device according to the second embodiment of the present invention, from the viewpoint of increasing the electromotive force, it is preferable that a magnet is arranged on one end face of the chip component. In this case, it is more preferable that another magnet with the same magnetic pole is arranged on the end face opposite to the end face on which the magnet is arranged. For example, in the thermoelectric conversion device 2 shown in Figs. 15 and 16, it is preferable that a magnet is arranged on one of the end faces facing each other in the z-axis direction, and it is more preferable that another magnet with the same magnetic pole is arranged on the other end face.

[0088] When a magnet is disposed on the end face of the chip component, the direction of the magnetic field generated by the magnet is preferably parallel to the axis of the winding. For example, in the thermoelectric conversion device 2 shown in Fig. 15 and Fig. 16, it is preferable to generate a magnetic field in the z-axis direction.

[0089] In the thermoelectric conversion device according to the second embodiment of the present invention, from the viewpoint of increasing the temperature gradient and increasing the electromotive voltage, it is preferable that a highly thermally conductive member such as a heat dissipation sheet is disposed on one end face of the chip component. For example, in the thermoelectric conversion device 2 shown in Fig. 15 and Fig. 16, it is preferable that a highly thermally conductive member such as a heat dissipation sheet is disposed on the outer periphery of the winding 40.

[0090] In the thermoelectric conversion device according to the second embodiment of the present invention, from the viewpoint of increasing heat dissipation and increasing electromotive voltage, it is preferable that one end face of the chip component has unevenness. For example, in the thermoelectric conversion device 2 shown in Fig. 15 and Fig. 16, it is preferable that the surface of the winding core part 30 has unevenness.

[0091] [Third embodiment] A thermoelectric conversion device according to a third embodiment of the present invention includes a plurality of substrates and meandering wiring provided on a main surface of each of the substrates. The meandering wiring includes a thermoelectric material having an anomalous Nernst effect. Adjacent substrates are disposed at an angle greater than 0 degrees and less than 180 degrees.

[0092] Fig. 17 is a perspective view showing a typical example of a thermoelectric conversion device according to a third embodiment of the present invention, and Fig. 18 is an exploded perspective view of the thermoelectric conversion device shown in Fig. 17.

[0093] The thermoelectric conversion device 3 shown in Fig. 17 is a chip component. The thermoelectric conversion device 3 shown in Fig. 17 and Fig. 18 includes a plurality of substrates 10 and meander wiring 20 provided on the main surface of each substrate 10. As shown in Fig. 17, the outer shape of the thermoelectric conversion device 3 is, for example, a polygonal prism such as a triangular prism.

[0094] 17 and 18, adjacent substrates 10 are disposed at an angle greater than 0 degrees and less than 180 degrees. The number of substrates 10 on which meander wiring 20 is provided is not particularly limited, but is, for example, 2 or more and 4 or less.

[0095] 17 and 18, the meander wiring 20 extends in the y-axis direction while meandering. The meander wiring 20 may be provided on the principal surface of each substrate 10 that is on the outer side of the thermoelectric conversion device 3, or on the inner principal surface. The shape of the meander wiring 20 in a plan view may be the same or different between the substrates 10.

[0096] The meander wiring 20 includes a thermoelectric material having the anomalous Nernst effect. As described in the first embodiment of the present invention, the meander wiring 20 may be configured such that first wiring made of a thermoelectric material and second wiring made of a conductor are alternately arranged in order to control the magnetization direction and increase the electromotive voltage. Note that the meander wiring 20 may be configured only with first wiring made of a thermoelectric material.

[0097] The thermoelectric material constituting the first wiring is, for example, Fe. 3 Sn, Fe 3 Al, Fe 3 Ga, Fe 3 Ge, Co 2 MnGa,Co 2 MnAl, Co 2 MnIn, Mn 3 Ga, Mn 3 Sn, Mn3 Ge, Fe 2 Examples include NiGa, CoTiSb, CoVSb, CoCrSb, CoMnSb, TiGa2Mn, etc.

[0098] Examples of conductors constituting the second wiring include Ag, Cu, Au, Ni, and Pt.

[0099] By arranging multiple substrates 10 provided with meandering wiring 20 including a thermoelectric material having the anomalous Nernst effect, the total length of the wiring including the thermoelectric material can be increased. Therefore, even if the temperature difference is small, a sufficient electromotive voltage per unit installation area can be obtained.

[0100] Furthermore, by arranging adjacent substrates 10 at an angle greater than 0 degrees and less than 180 degrees, electromotive voltages can be obtained from heat fluxes in a plurality of directions.

[0101] For example, in FIG. 17 and FIG. 18, when the meander wiring 20 is magnetized in the positive direction of the y-axis, an electromotive voltage can be obtained from heat fluxes in three directions perpendicular to each substrate 10.

[0102] As shown in Fig. 17 and Fig. 18, a pair of substrates may be disposed facing each other in the y-axis direction. Although not shown in Fig. 17 and Fig. 18, it is preferable that an external electrode electrically connected to the meander wiring 20 is provided on the surface of the thermoelectric conversion device 3.

[0103] The material constituting the substrate 10 is not particularly limited, but a ceramic material having low thermal conductivity and low electrical conductivity is preferable. Examples of the ceramic material constituting the substrate 10 include aluminum nitride, boron nitride, silicon carbide, alumina, spinel oxide, and perovskite oxide. The material constituting the substrate 10 may be a ceramic material, a glass material, or a resin material. When the thermoelectric material and the substrate 10 are simultaneously fired, a low-temperature co-fired ceramic material is preferable in order not to change the ordered phase of the thermoelectric material. Examples of the low-temperature co-fired ceramic material include a composite material containing borosilicate glass and alumina. From the viewpoint of passing a large heat flow through the meander wiring 20 to generate a high electromotive force, it is preferable that the thermal conductivity of the ceramic material constituting the substrate 10 is low. However, when measuring a change in instantaneous heat flux, it is preferable that the thermal conductivity of the ceramic material constituting the substrate 10 is high from the viewpoint of passing the heat flow quickly to the thermoelectric conversion device 3. From the viewpoint of suppressing electrical short circuits between the meander wirings 20, it is preferable that the electrical conductivity of the ceramic material constituting the substrate 10 is low.

[0104] The material constituting the substrate 10 may include a material having a temperature coefficient of resistance. For example, when the substrate 10 includes an NTC material, an internal conductor for temperature detection is formed inside the chip component, so that the ambient temperature and heat flux can be measured simultaneously.

[0105] In the thermoelectric conversion device according to the third embodiment of the present invention, from the viewpoint of increasing the electromotive force, it is preferable that a magnet is arranged on one end face of the chip component. In this case, it is more preferable that another magnet with the same magnetic pole is arranged on the end face opposite to the end face on which the magnet is arranged. For example, in the thermoelectric conversion device 3 shown in Figs. 17 and 18, it is preferable that a magnet is arranged on one of the end faces facing each other in the y-axis direction, and it is more preferable that another magnet with the same magnetic pole is arranged on the other end face.

[0106] When a magnet is disposed on the end face of the chip component, the direction of the magnetic field formed by the magnet is preferably perpendicular to the direction of the current flowing through the first wiring and the direction of the heat flow. For example, in the thermoelectric conversion device 3 shown in Fig. 17 and Fig. 18, it is preferable to form a magnetic field in the y-axis direction.

[0107] In the thermoelectric conversion device according to the third embodiment of the present invention, from the viewpoint of increasing the temperature gradient and raising the electromotive voltage, it is preferable that a highly thermally conductive member such as a heat dissipation sheet is disposed on at least one end face of the chip component.

[0108] In the thermoelectric conversion device according to the third embodiment of the present invention, from the viewpoint of increasing heat dissipation and increasing the electromotive voltage, it is preferable that at least one end face of the chip component has projections and recesses.

[0109] The thermoelectric conversion device according to the third embodiment of the present invention may include a plurality of meandering wirings whose directions differ between the substrates. EXAMPLES

[0110] EXAMPLES Hereinafter, examples that more specifically disclose the thermoelectric conversion device of the present invention will be described, however, the present invention is not limited to only these examples.

[0111] [Example 1] Chemical formula Mn 3 The thermoelectric material represented by Sn and containing the ordered structure DO3 was pulverized to obtain a thermoelectric material powder having an average particle size of 5 μm. The average particle size of the thermoelectric material powder is preferably 0.05 μm or more and 300 μm or less.

[0112] The above thermoelectric material powder was mixed with a resin binder, an organic solvent, a dispersant, and a plasticizer to obtain a thermoelectric material paste.

[0113] A low-temperature co-fired ceramic powder, which was a mixture of borosilicate glass powder and alumina powder, was mixed with a resin binder, an organic solvent, a dispersant, and a plasticizer to obtain an element paste.

[0114] Silver (Ag) powder was mixed with a resin binder, an organic solvent, a dispersant, and a plasticizer to obtain a conductive paste.

[0115] An element layer of 20 μm thickness was formed by screen printing of element paste.

[0116] On the upper surface of the element layer, a meandering wiring having the structure shown in Figure 2 was formed by screen printing of a thermoelectric paste and a conductive paste.

[0117] The element paste was printed using a meander wiring negative screen.

[0118] The above printing was repeated to obtain a green chip having a laminated structure. The ends of the meandering wiring were exposed at both ends of the green chip.

[0119] The green chip was degreased in air at 350° C. for 2 hours, and then sintered in an argon atmosphere at 900° C. for 1 hour.

[0120] The fired chip was subjected to barrel processing, and then coated with an external electrode paste, baked and plated, followed by washing and drying.

[0121] In this manner, a thermoelectric conversion device 1 was obtained.

[0122] [Example 2] Chemical formula Fe 3 A thermoelectric material represented by Al and containing an ordered structure DO3 was used to obtain a winding wire having a wire diameter of 250 μm by melt spinning. The wire diameter of the winding wire is preferably 100 μm or more and 500 μm or less.

[0123] The surface of the winding is coated with a polyimide insulating coating.

[0124] Alumina (Al) with an average particle size of 2 μm 2 O 3 The powder was mixed with an organic solvent, a dispersant, and a plasticizer, and then spray-dried to obtain a powder of the powdered matrix.

[0125] The granulated powder was press-molded, then degreased and sintered to obtain a core portion.

[0126] The wire was wound around the core for 20 turns.

[0127] An electrode was formed on the bottom surface of the flange of the core.

[0128] The ends of the winding were connected to electrodes on the bottom surface of the flange of the winding core.

[0129] In this manner, a thermoelectric conversion device 2 was obtained.

[0130] [Example 3] Chemical formula Mn 3 The thermoelectric material represented by Sn and containing the ordered structure DO3 was pulverized to obtain a thermoelectric material powder having an average particle size of 5 μm. The average particle size of the thermoelectric material powder is preferably 0.05 μm or more and 300 μm or less.

[0131] The above thermoelectric material powder was mixed with a thermosetting resin binder, an organic solvent, a dispersant, and a plasticizer to obtain a thermoelectric material paste.

[0132] Alumina (Al 2 O 3 ) On the surface of the substrate, a meandering wiring having the structure shown in Figure 18 was formed by screen printing a thermoelectric paste and a conductive adhesive. The ends of the meandering wiring were exposed at both ends of the substrate.

[0133] The alumina substrate on which the meandering wiring was formed was heated in air at 250°C for 2 hours to harden the conductive paste.

[0134] After firing, the three substrates were arranged at a 60 degree angle to each other and glued together.

[0135] In this manner, a thermoelectric conversion device 3 was obtained.

[0136] [Sensor sensitivity calculation] The sensitivity as a sensor was calculated for the thermoelectric conversion device 1 shown in FIG. 2, the thermoelectric conversion device 1B shown in FIG. 5, and the thermoelectric conversion device 2 shown in FIG. 15 by the following formula. Sensitivity [V / (W*m -2 )]=S N L / κ S N : Anomalous Nernst coefficient [V / K] L: Total length of magnetic wiring [m] κ: Thermal conductivity of magnetic wiring [W / (m*K)]

[0137] Specifically, the anomalous Nernst coefficient S N The sensitivity range (upper and lower limits) was calculated assuming a thermal conductivity of 15 to 25 W / (m*K) and a thermal conductivity of 1 to 6 μV / K.

[0138] For the thermoelectric conversion device 1 shown in FIG. 2, the sensitivity was calculated with an overall size of 2 mm × 2 mm, number of layers: 1 or 20, width of first wiring 21 / width of second wiring 22 / spacing of meander wiring 20: 20 μm / 20 μm / 20 μm, and side gap (distance between the end face of substrate 10 and meander wiring 20 in the x-axis direction): 30 μm.

[0139] When the number of layers is one, the sensitivity is 0.002 to 0.019 μV / (W*m -2 ), whereas when two or more layers are laminated, the sensitivity increases according to the number of layers. For example, when the number of layers is 20, the sensitivity is 0.038 to 0.376 μV / (W*m -2 ), which provides much higher sensitivity than a single-layer structure.

[0140] For the thermoelectric conversion device 1B shown in FIG. 5, the sensitivity was calculated with an overall size of 2 mm × 2 mm, number of layers: 1 or 10, width of first wiring 21 / width of second wiring 22 / spacing of meander wiring 20B: 20 ​​μm / 20 μm / 20 μm, and side gap (distance between substrate 10 and meander wiring 20B in the x-axis direction): 30 μm.

[0141] When the first wiring 21, which is a magnetic wiring, is a single layer, the sensitivity is 0.004 to 0.038 μV / (W*m -2 ), whereas when two or more layers are laminated, the sensitivity increases according to the number of layers. For example, when ten layers of the first wiring 21, which is a magnetic wiring, are laminated, the sensitivity is 0.038 to 0.376 μV / (W*m -2 ), which provides much higher sensitivity than a single-layer structure.

[0142] In the thermoelectric conversion device 2 shown in FIG. 15, the sensitivity was calculated with a bottom size of 4 mm×4 mm, a diameter of the winding core part of 2 mm, a height of the winding core part of 3 mm, and a diameter of the winding wire of 200 μm (1 turn or 3 turns).

[0143] The sensitivity for one turn is 0.004~0.039μV / (W*m -2 ), whereas the sensitivity of two or more turns increases according to the number of turns. For example, the sensitivity of three turns is 0.013 to 0.134 μV / (W*m -2 ) which gives a much higher sensitivity than the single-turn configuration. [Explanation of symbols]

[0144] 1, 1A, 1B, 1C, 1D, 1E, 1F, 1G, 1H, 2, 3 Thermoelectric conversion devices 10 Substrate 11 Base 20, 20A, 20B, 20C, 20D, 20E, 20F, 20G, 20H Meander wiring 21 1st wiring 22 2nd wiring 23 Via conductor 24, 25 external electrode 30 Winding core 40 Windings 41, 42 electrode I Current direction M magnetization direction Q Heat flow direction

Claims

1. An element body including a plurality of stacked substrates; a meander wiring provided inside the element body and having a laminated structure; the meander wire includes a thermoelectric material having an anomalous Nernst effect; the meander wiring extends in a direction along a main surface of the substrate and has a layered structure in a layering direction of the substrate, the meander wiring includes a first wiring made of a thermoelectric material and a second wiring made of a conductor, A thermoelectric conversion device, wherein the width of the second wiring is smaller than the width of the first wiring, the thickness of the second wiring is smaller than the thickness of the first wiring, or both.

2. An element body including a plurality of stacked substrates; a meander wiring provided inside the element body and having a laminated structure; the meander wire includes a thermoelectric material having an anomalous Nernst effect; The meander wiring extends in a stacking direction of the substrate and has a stacked structure in a main surface direction of the substrate.

3. the meander wiring includes a first wiring made of a thermoelectric material and a second wiring made of a conductor, The thermoelectric conversion device according to claim 2 , wherein the width of the second wiring is smaller than the width of the first wiring, the thickness of the second wiring is smaller than the thickness of the first wiring, or both.

4. The thermoelectric conversion device according to claim 2 , wherein the meander wiring includes only a first wiring made of a thermoelectric material.

5. The thermoelectric conversion device according to any one of claims 1 to 4, wherein the thermoelectric conversion device is a chip component.

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