JP5630230B2 - Thermoelectric conversion element - Google Patents

Description

  The present invention relates to a thermoelectric conversion element and a thermoelectric conversion method based on a magnetic material.

  Expectations for thermal energy recovery technology are increasing as efforts to address environmental and energy issues toward a sustainable society become active. Heat can be recovered from various scenes such as body temperature, solar heat, engine, industrial waste heat, etc., is the most common energy source, and the need for heat recovery technology to realize an energy-efficient low-carbon society Is increasing.

  Thermoelectric conversion elements based on the Seebeck effect (or Peltier effect) have already been used in various situations, such as temperature difference power generation, heat sensors, and cooling. It is expected as a power supply / power supply device for driving small terminals and sensors. The thermoelectric conversion element has a module structure in which many thermocouples, which are a combination of p-type and n-type semiconductors, are connected in series. Since there are no moving parts, there is no noise / vibration, no scale effect, and small temperature difference. However, it has many advantages such as being able to generate electricity and being incorporated into various devices and environments.

  In recent years, a spin Seebeck effect has been discovered in which a magnetic material is given a temperature gradient to generate a flow of electron spin. Patent Document 1, Non-Patent Documents 1 and 2 describe spin thermoelectric conversion elements based thereon. Has been.

  The spin thermoelectric conversion element described in Patent Document 1 is composed of a ferromagnetic material and a metal electrode. When a temperature gradient is applied to a ferromagnetic material, a spin current is induced in a direction along the temperature gradient by the spin Seebeck effect. This induced spin current can be taken out as a current by the spin Hall effect in the metal electrode in contact with the magnetic material. Thereby, the temperature difference power generation which takes out electric power from heat similarly to the thermoelectric conversion element based on the Seebeck effect is attained.

JP2009-130070

  However, the thermoelectric conversion element described above has some problems in increasing the thermoelectromotive force output. A thermoelectric conversion element based on the Seebeck effect needs to have a structure in which a large number of thermocouples composed of a p-type semiconductor and an n-type semiconductor are electrically connected in series in order to increase the output voltage. Due to such a complicated structure, an increase in manufacturing cost is inevitable, and there is a problem in durability and impact resistance.

  On the other hand, in the case of a spin thermoelectric conversion element based on the spin Seebeck effect, it is not necessary to create a complicated structure, and it is possible in principle to increase the output of thermoelectromotive force simply by lengthening the metal electrode. Patent Document 1 describes a structure in which when a spin thermoelectric conversion element is applied to a heat source on a pipe, the number of windings is increased in the form of a roll cake in order to increase the thermoelectromotive force. Therefore, it is necessary to increase the number of turns as the output is increased, and there is a problem in miniaturization.

  The objective of this invention is providing the thermoelectric conversion element which solves the subject mentioned above.

  The thermoelectric conversion element according to the present invention includes a magnetic body having at least one magnetization direction and a plurality of electromotive bodies including a material disposed on a plane substantially parallel to the magnetization direction and having a spin orbit interaction. It is comprised, It connects in series so that the electromotive force of these electromotive bodies may be added, It is characterized by the above-mentioned.

  The thermoelectric conversion element according to the present invention can realize both high output and space saving.

It is a perspective view of the thermoelectric conversion element in a 1st embodiment. It is a perspective view of the thermoelectric conversion element in 2nd Embodiment. It is a perspective view of the thermoelectric conversion element in 2nd Embodiment. It is a top view of the thermoelectric conversion element in 2nd Embodiment. It is a top view of the thermoelectric conversion element in 2nd Embodiment. It is a top view of the thermoelectric conversion element in 3rd Embodiment. It is a top view of the thermoelectric conversion element in 3rd Embodiment. It is a top view of the thermoelectric conversion element in 4th Embodiment. It is a top view of the thermoelectric conversion element in 4th Embodiment. It is a top view of the thermoelectric conversion element in 5th Embodiment. It is a top view of the thermoelectric conversion element in 5th Embodiment. 1 is a perspective view of a thermoelectric conversion element in Example 1. FIG. 3 is a top view of the thermoelectric conversion element in Example 1. FIG. 6 is a top view of a thermoelectric conversion element in Example 2. FIG.

  Hereinafter, preferred embodiments for carrying out the present invention will be described with reference to the drawings. However, the preferred embodiments described below are technically preferable for carrying out the present invention, but the scope of the invention is not limited to the following.

  [First Embodiment] Next, this embodiment will be described in detail with reference to the drawings. FIG. 1 is a perspective view of a thermoelectric conversion element 1 in the present embodiment.

  [Description of Configuration] As shown in FIG. 1, the thermoelectric conversion element 1 in this embodiment includes a magnetic body 2 and an electromotive body 3.

The magnetic body 2 is a material having at least one magnetization direction. The magnetic body 2 is preferably a magnetic insulator because a material having a smaller thermal conductivity acts on the thermoelectric effect more efficiently. In this embodiment, for example, a garnet-based magnetic material can be used as the magnetic insulator, and yttrium iron garnet (Y ₃ Fe ₅ O ₁₂ , hereinafter abbreviated as YIG) is preferable. The material of the magnetic body 2 is not limited to the above, and a ferromagnetic metal such as permalloy that is an alloy of iron and nickel can also be used. The shape of the magnetic body 2 is preferably a flat plate shape, but is not particularly limited, and may have some planar roughness or distortion.

  The magnetic body 2 is formed by liquid phase epitaxial growth (LPE), sputtering, laser ablation (PLD), metal organic deposition method (MOD method), aerosol deposition method (AD method), or the like. In particular, the AD method is desirable for applications where a large area of a magnetic insulator such as YIG is formed on a plastic substrate. The film thickness of the magnetic body 2 can be changed according to the application of the thermoelectric power generation and the temperature range, but is usually set to about 100 nm to 500 μm.

A plurality of electromotive bodies 3 are provided on a plane substantially parallel to the magnetization direction of the magnetic body 2 and are connected in series so that electromotive forces generated by the individual electromotive bodies 3 are added. The electromotive force thus added is finally taken out as an added electromotive force V _sum between one end (A) and the other end (B) of the electromotive body 3. Note that the plurality of electromotive bodies 3 may not be provided in contact with the magnetic body 2 and may be provided above the magnetic body 2. That is, a gap or another structure may be provided between the electromotive body 3 and the magnetic body 2.

  The electromotive body 3 includes a material having a spin orbit interaction. For example, a metal material such as Au, Pt, or Pd having a relatively large spin orbit interaction or an alloy material thereof is used. The electromotive body 3 may be doped with impurities such as Fe and Cu in order to enhance the spin Hall effect. Here, it is preferable that the thickness of the electromotive body 3 is set to at least the spin diffusion length of the metal material. For example, it is desirable to set 50 nm or more for Au and 10 nm or more for Pt.

  [Explanation of Action] In the thermoelectric conversion element 1 of FIG. 1, when a temperature gradient is applied in the vertical direction (z direction in the drawing), the spin flow in the z direction parallel to the temperature gradient is caused by the spin Seebeck effect of the magnetic body 2. (Spin current) is induced.

  The spin current generated in the magnetic body 2 flows into the electromotive bodies 3 connected in series with each other. Thereafter, due to the reverse spin Hall effect in the electromotive body 3, the flow of the spin current is converted into a current (electromotive force) in the x direction that is perpendicular to the magnetization direction. That is, the thermoelectric conversion element 1 composed of the magnetic body 2 and the electromotive body 3 generates an electromotive force from the applied temperature gradient.

As a result of the series connection structure, the electromotive forces generated by the individual electromotive bodies 3 are added and extracted between the ends as the added electromotive force _Vsum . That is, the added electromotive force V _sum is the _sum of the electromotive forces in the individual electromotive bodies 3.

  Here, the electromotive force in each electromotive body 3 includes both the magnetization direction of the magnetic body 2 and the direction in which the spin current flows from the magnetic body 2 into the electromotive body 3 because of the symmetry required by the inverse spin Hall effect. Is always generated in one direction perpendicular to (the cross product direction of two vectors).

For example, in the arrangement shown in FIG. 1, since the magnetization direction is the y direction and the spin current flows in the z direction, the electromotive force is always generated in the x direction in each electromotive body 3. Therefore, when the electromotive members are connected in series as shown in FIG. 1, a positive contribution is made to the added voltage V _sum (an electromotive force is generated from one end (A) to the other end (B). Some electromotives make a negative contribution (generate electromotive force from the other end (B) toward one end (A)).

Therefore, the electromotive force generation efficiency in the electromotive body that generates electromotive force from one end (A) to the other end (B) is one end (A) from the other end (B). The element structure is designed so as to be larger than the electromotive force generation efficiency of the electromotive body that generates the electromotive force toward. As a result, added voltage V _sum of the electromotive element 3 connected in series is added to the positive as a whole. Of course, the above design may be reversed so that the addition voltage _Vsum is added negatively as a whole. If the above conditions are satisfied, the shape of the electromotive body 3 is not limited.

  From the symmetry for generating an electromotive force by the reverse spin Hall effect, the magnetization direction of the magnetic body 2, the direction of the spin current flowing into the electromotive body 3, and the stretching direction of the electromotive body 3 (the electromotive force is added) However, the structure of the thermoelectric conversion element 1 is not limited to that of the present embodiment as long as the arrangement satisfies these conditions. The magnetization direction of the magnetic body 2 and the arrangement of the electromotive body 3 with respect to the magnetic body 2 can be flexibly changed.

  [Explanation of Effects] The thermoelectric conversion element 1 in this embodiment is connected in series so that the electromotive force 3 provided above the magnetic material 2 is added with electromotive force. Therefore, the thermoelectric conversion element 1 can take out a high output in a small space.

  [Second Embodiment] Next, a second embodiment will be described with reference to FIG. FIG. 2 is a perspective view of the thermoelectric conversion element 1 in the present embodiment.

  [Description of Configuration] As shown in FIG. 2, the thermoelectric conversion element 1 in this embodiment includes a magnetic body 2 and an electromotive body 3 as in the first embodiment, and further includes a conductor 4. And output terminals 5 and 6.

  Similar to the first embodiment, the magnetic body 2 is a material having at least one magnetization direction, and is preferably a magnetic insulator, but a metal magnetic body can also be used. Further, the shape of the magnetic body 2 is preferably a flat plate shape, but is not particularly limited, and there may be some planar roughness or distortion.

  As in the first embodiment, a plurality of electromotive bodies 3 are provided on a surface substantially parallel to the magnetization direction of the magnetic body 2, and the longitudinal direction is substantially perpendicular to the magnetization direction of the magnetic body 2. It is the shape which has. In addition, a gap or another structure may be provided between the electromotive body 3 and the magnetic body 2.

  Here, in contrast to the electromotive body 3 that generates an electromotive force from the output terminal 5 toward the output terminal 6, the portion that generates the electromotive force from the output terminal 6 toward the output terminal 5 is referred to as the conductor 4. The electromotive force generation efficiency of the electromotive body 3 is greater than the electromotive force generation efficiency of the conductor 4.

  The plurality of electromotive bodies 3 are arranged substantially parallel to each other. The conductor 4 connects one end in the extending direction of the electromotive body 3 and the other end of the adjacent electromotive body 3. That is, the electromotive bodies 3 and the conductors 4 are alternately and continuously connected to each other to form a folded shape (zigzag meander shape) as shown in FIG.

  In addition, if the electromotive force production | generation efficiency of the electromotive body 3 is larger than the electromotive force production | generation efficiency of the conductor 4, the shape and arrangement | positioning of the connection of the electromotive body 3 and the conductor 4 will not be specifically limited. For example, the electromotive body 3 and the conductor 4 may be connected obliquely to each other as shown in FIG. Moreover, the spiral shape provided with the linear electromotive body 3 and the conductor 4 as shown in FIG. 4, and the spiral shape provided with the curved electromotive body 3 and the conductor 4 as shown in FIG. But you can.

  Further, the conductor 4 is not necessarily limited to the end portion of the electromotive body 3, and may be connected at a position closer to the center portion than the end portion.

  The output terminal 5 and the output terminal 6 are provided at the other end of the electromotive body 3 in which only one end is connected to the other electromotive body 3 (or the conductor 4). By providing the electromotive body 3 in this way, the maximum electromotive force (output voltage) can be obtained.

  Moreover, you may provide the several electromotive body 3 and the conductor 4 on the same plane.

  [Explanation of Action] When a temperature gradient is applied in the vertical direction with respect to the magnetization direction in which the magnetic body 2 acts in the plane direction, the spin flow (in the temperature gradient direction) due to the spin Seebeck effect of the magnetic body 2 ( Spin current) is induced.

  The spin current generated in the magnetic body 2 is converted into a current flowing in the extending direction of the electromotive body 3 and the conductor 4 perpendicular to the magnetization direction by the spin Hall effect of the electromotive bodies 3 connected in series with each other. Is done. That is, the thermoelectric conversion element 1 composed of the magnetic body 2, the electromotive body 3, and the conductor 4 generates electric power from the applied temperature gradient. Here, since the electromotive force 3 has higher electromotive force generation efficiency than the conductor 4, a current flows in one direction from the output terminal 5 to the output terminal 6.

  [Explanation of Effect] In the thermoelectric conversion element 1 according to the present embodiment, a plurality of electromotive bodies 3 provided on a magnetic body 2 are formed by conductors 4, and the electromotive bodies 3 and 4 are folded or spiral. Connected to form. With the structure described above, the electromotive forces can be effectively added from the output terminal 5 toward the output terminal 6 without canceling the electromotive forces at the folded portion or the like. As a result, the thermoelectric conversion element 1 can take out a high output in a small space without increasing its size.

  [Third Embodiment] Next, a third embodiment will be described. FIG. 6 is a top view of the thermoelectric conversion element 1 of the present embodiment.

  [Description of Structure] In this embodiment, as shown in FIG. 6, the materials of the electromotive body 3 and the conductor 4 are different. Other structures and connection relationships are the same as those in the second embodiment. That is, the thermoelectric conversion element 1 of the third embodiment includes a magnetic body 2, an electromotive body 3, a conductor 4, and output terminals 5 and 6.

  The electromotive body 3 is made of a metal having a large spin Hall effect (electromotive force generation efficiency) as in the first embodiment. For example, Pt or Au is preferable, but not limited thereto. The electromotive body 3 may be doped with impurities such as Fe and Cu in order to enhance the spin Hall effect.

  On the other hand, the conductor 4 is made of a metal having a small spin Hall effect (electromotive force generation efficiency). For example, the conductor 4 is preferably Cu or Al. However, the conductor 4 is not limited to this as long as the material has a smaller spin Hall effect than the electromotive body 3.

  [Explanation of Action / Effect] When a temperature gradient is applied in the vertical direction with respect to the magnetization direction in which the magnetic body 2 is acting in a plane direction, the spin Seebeck effect of the magnetic body 2 causes the spin in the temperature gradient direction. A flow (spin current) is induced.

The spin current generated in the magnetic body 2 is converted into a current flowing in the extending direction of the electromotive body 3, which is perpendicular to the magnetization direction, by the spin Hall effect of the electromotive bodies 3 connected in series with each other. That is, the thermoelectric conversion element 1 composed of the magnetic body 2 and the electromotive body 3 generates electric power from the applied temperature gradient. That is, the electromotive force is generated in the electromotive body 3 in one direction determined by the temperature gradient direction and the magnetization direction of the magnetic body 2. (Right direction in FIG. 6)
However, when the thermoelectric conversion element 1 has a simple folded structure, the directions of the currents taken out from the magnetic body 2 and generated in the electromotive body 3 and the conductor 4 are all rightward in the drawing, and therefore are shown in FIG. In this way, the currents cancel each other at the folded portion, and the output voltage may be canceled.

  Therefore, in the present embodiment, materials having different spin Hall effects (electromotive force generation efficiency) are applied to the electromotive body 3 and the conductor 4. That is, the electromotive body 3 is made of a material having a large spin Hall effect, and the conductor 4 is made of a material having a small spin Hall effect.

  That is, when generating a current flowing from the output terminal 5 to the output terminal 6, the electromotive body 3 that generates an electromotive force from the output terminal 5 toward the output terminal 6 is made of a material having a large spin Hall effect. On the other hand, the conductor 4 that generates an electromotive force from the output terminal 6 toward the output terminal 5 is made of a material having a small spin Hall effect.

  By changing the material as described above, the spin current flowing into the conductor 4 is hardly converted into current, and the spin current flowing into the electromotive body 3 is converted into current. Therefore, the output voltage can be efficiently taken out in one direction from the output terminal 5 to the output terminal 6.

  [Fourth Embodiment] Next, a fourth embodiment will be described. FIG. 8 is a top view of the thermoelectric conversion element 1 of the present embodiment.

  [Description of Structure] This embodiment is different from the second embodiment in that the widths of the electromotive body 3 and the conductor 4 in the extending direction are different as shown in FIG. Other structures and connection relationships are the same as those in the second embodiment. That is, the thermoelectric conversion element 1 of the fourth embodiment includes a magnetic body 2, an electromotive body 3, a conductor 4, and output terminals 5 and 6.

  The plurality of electromotive bodies 3 in the present embodiment are disposed substantially parallel to each other. The conductor 4 connects one end in the extending direction of the electromotive body 3 and the other end of the adjacent electromotive body 3.

  The width of the conductor 4 in the extending direction is shorter than the width of the electromotive body 3 in the extending direction. In addition, since the conductor 4 in this embodiment differs in the width | variety of an extending | stretching direction, you may form with the same material as the electromotive body 3, and the spin Hall effect (electromotive force production | generation efficiency) is more than the electromotive body 3. If it is a small metal, it will not be limited.

  Further, as shown in FIG. 9, a dielectric 4 having a narrower width than the electromotive bodies 3 may be connected in an oblique direction between the adjacent electromotive bodies 3.

  [Explanation of Action / Effect] When a temperature gradient is applied in the vertical direction with respect to the magnetization direction in which the magnetic body 2 is acting in a plane direction, the spin Seebeck effect of the magnetic body 2 causes the spin in the temperature gradient direction. A flow (spin current) is induced.

The spin current generated in the magnetic body 2 is converted into a current flowing in the extending direction of the electromotive body 3, which is perpendicular to the magnetization direction, by the spin Hall effect of the electromotive bodies 3 connected in series with each other. That is, the thermoelectric conversion element 1 composed of the magnetic body 2 and the electromotive body 3 generates electric power from the applied temperature gradient. That is, the electromotive force is generated in the electromotive body 3 in one direction determined by the temperature gradient direction and the magnetization direction of the magnetic body 2. (In FIG. 8, right direction)
However, when the thermoelectric conversion element 1 has a simple folded structure, since the directions of currents generated in the magnetic body 2 are all rightward in the drawing, the currents cancel each other at the folded portion as shown in FIG. As a result, the output may be canceled.

  Therefore, in this embodiment, the width in the extending direction of the electromotive body 3 is made larger than the width in the extending direction of the conductor 4. With this structure, the current converted from the spin current in the electromotive body 3 can be made larger than the current converted from the spin current in the conductor 4. As a result, the output voltage can be efficiently extracted in one direction.

  That is, when generating a current that flows from the output terminal 5 to the output terminal 6, the width in the extending direction of the electromotive body 3 that generates an electromotive force from the output terminal 5 toward the output terminal 6 is increased, whereas the output terminal The width in the extending direction of the conductor 4 that generates an electromotive force from 6 toward the output terminal 5 was reduced.

  Moreover, since the electromotive body 3 and the conductor 4 in this embodiment can be formed with the same material, they can be formed with fewer processes.

  [Fifth Embodiment] Next, a fifth embodiment will be described. FIG. 10 is a top view of the thermoelectric conversion element 1 of the present embodiment.

  [Description of Configuration] This embodiment is different from the second embodiment in that a barrier layer 8 for blocking the spin current is provided between the conductor 4 and the magnetic body 2 as shown in FIG. is there. Other structures and connection relationships are the same as those in the second embodiment. That is, the thermoelectric conversion element 1 of the fifth embodiment includes a magnetic body 2, an electromotive body 3, and output terminals 5 and 6.

  The plurality of electromotive bodies 3 in the present embodiment are arranged in parallel with each other. The conductor 4 connects one end in the extending direction of the electromotive body 3 and the other end of the adjacent electromotive body 3. The connection shape and arrangement of the conductor 4 are not particularly limited. For example, the electromotive body 3 and the conductor 4 are folded back (connected to form a zigzag meander shape as shown in FIG. 2, or connected obliquely as shown in FIG. 3), or FIG. Alternatively, a spiral shape as shown in FIG. 5 may be used.

  In the present embodiment, the same material having a large spin Hall effect is used for the electromotive body 3 and the conductor 4. However, while the electromotive body 3 is in direct contact with the magnetic body 2, a barrier layer 8 that blocks the spin current is inserted between the conductor 4 and the magnetic body 2.

  [Description of Actions and Effects] By inserting the barrier layer 8 only between the conductor 4 and the magnetic body 2 as described above, the spin current generated by the temperature gradient is blocked by the barrier layer 8, and the conductor 4 Then, no current is generated. As a result, the output voltage can be taken out in one direction without canceling the current between the electromotive body 3 and the conductor 4. The electrodes can also be formed in a spiral shape as shown in FIG.

  [Embodiment 1] Embodiment 1 will now be described. FIG. 12 is a perspective view of the thermoelectric conversion element 1 of the present embodiment, and FIG. 13 is a top view.

  [Description of Structure] The thermoelectric conversion element 1 in this embodiment is provided with a magnetic body 2, an electromotive body 3, a conductor 4, an output terminal 5, an output terminal 6, and a substrate 7.

  The substrate 7 is a polyimide substrate having a thickness of 300 μm.

  The magnetic body 2 uses yttrium iron garnet (hereinafter referred to as YIG) and forms a YIG film having a film thickness of 200 μm on the substrate by using an aerosol deposition (AD) method capable of forming a film at room temperature.

  The electromotive body 3 is made of Au, the conductor 4 is made of Cu, and a folded pattern as shown in FIG. 13 is formed. The film thickness of Au as the electromotive body 3 is 100 nm, the width is 4 mm, and the length is 40 mm. Similarly, the film thickness of Cu as the conductor 4 is also 100 nm, the width is 4 mm, and the length is 40 mm. The conductor 4 is provided with convex portions respectively connected to two electromotive bodies 3 opposed to each other with the conductor 4 interposed therebetween at both ends in the extending direction. In addition, the space | interval of the electromotive body 3 and the conductor 4 shall be 0.5 mm.

  An electrode structure having a rectangular size of 40 mm × 40 mm is formed by folding back an electrode composed of the electromotive body 3 (outward path) and the conductor 4 (return path). By these foldings, the total length of the electrode is 364 mm. The overall resistance is 11.1Ω (Au portion) + 6.9Ω (Cu portion) = 18.0Ω from the electrical conductivity of each material (Au: 45.2 × 106 S / m, Cu: 59.6 × 106 S / m) . Thereby, since the amount of current generated in the electromotive body 3 (outward path) is larger than the amount of current generated in the conductor 4 (return path), the electromotive force is taken out between the output terminal 5 and the output terminal 6. Can do.

  [Manufacturing Method] Dry YIG fine particles having an average diameter of 300 nm are used as the raw material of the magnetic body 2 and packed in an aerosol generating container. The substrate 7 is fixed to a holder in the film forming chamber. In this state, a pressure difference is generated between the film forming chamber and the aerosol generating container, whereby YIG fine particles are drawn into the film forming chamber and sprayed onto the substrate 7 through the nozzle.

  At this time, the YIG fine particles are crushed and recombined by the collision energy with the substrate 7, and a YIG polycrystal is formed on the substrate 7. A uniform YIG film is formed on the substrate 7 by scanning the stage two-dimensionally.

  The electromotive body 3 is formed by an ink jet method. First, using Au nanometal ink made by ULVAC, ink is ejected onto the YIG film by an ink jet device, and the electromotive body 3 (outward path) of the folded electrode is formed of Au. Thereafter, the conductor 4 (return path) of the folded electrode is similarly formed of Cu using Cu nano ink.

  [Embodiment 2] Embodiment 2 will now be described. FIG. 14 is a top view of the thermoelectric conversion element 1 of the present embodiment.

  [Description of Structure] The thermoelectric conversion element 1 in this embodiment is provided with a magnetic body 2, an electromotive body 3, a conductor 4, an output terminal 5, an output terminal 6, and a substrate 7.

  As the substrate 7, a polyimide substrate having a thickness of 500 μm is used.

  A YIG film having a film thickness of 200 μm is formed as the magnetic body 2 by the aerosol deposition (AD) method as in the first embodiment.

  Unlike Example 1, instead of forming with only one kind of Au, structural asymmetry between the electromotive body 3 (outward path) and the conductor 4 (return path) is used as shown in FIG. The film thickness of the electromotive body 3 and the conductor 4 is 100 nm, the electrode width of the electromotive body 3 (outward path) is 3 mm, and the electrode width of the conductor 4 (return path) is narrowed to 1 mm. As a result, since the amount of current generated in the conductor 4 (outward path) is larger than the amount of current generated in the conductor 4 (return path), the electromotive force can be taken out between the output terminal 5 and the output terminal 6. it can.

  [Description of Manufacturing Method] As in Example 1, the magnetic body 2 is formed on the substrate 7 by the AD method.

  The electromotive body 3 is formed by an electroless gold plating method. Using a gold plating solution containing gold sodium sulfite as a gold salt manufactured by Hitachi Chemical Co., Ltd., a gold plating film is formed on the YIG film using hypophosphite as a reducing agent.

  The application of the present invention is not limited to thermoelectric power generation that generates electric power from a temperature gradient. For example, it can be used as a highly sensitive heat sensor by increasing the effective electromotive force by increasing the effective length of the electrode by a folded structure. The electrode structure of the present invention can also be applied as an electrode for Peltier cooling, which is the opposite effect of thermoelectric power generation.

DESCRIPTION OF SYMBOLS 1 Thermoelectric conversion element 2 Magnetic body 3 Electromotive body 4 Electric conductor 5 Output terminal 6 Output terminal 7 Board | substrate 8 Barrier layer

Claims (10)

One and the magnetic material having a unidirectional magnetization direction,
A plurality of electromotive members disposed on the one magnetic body ;
The plurality of electromotive bodies includes a material having a spin orbit interaction,
The thermoelectric conversion element is connected in series so that the electromotive forces of the plurality of electromotive bodies are added. In the electromotive bodies connected in series with each other,
The electromotive force generation efficiency of the electromotive body that generates an electromotive force from one end to the other end is:
2. The thermoelectric conversion element according to claim 1, wherein the electromotive force generation efficiency of the electromotive body that generates an electromotive force from the other end portion toward the one end portion is larger than the electromotive force generation efficiency.   The thermoelectric conversion element according to claim 2, wherein the plurality of electromotive bodies have a shape having a longitudinal direction in a direction substantially perpendicular to the magnetization direction, and are disposed substantially parallel to each other.   The at least one of the plurality of electromotive bodies is provided with an output terminal at one end portion in a longitudinal direction, and the other end portion is connected to the other electromotive body. 3. The thermoelectric conversion element according to 3. The electromotive body that generates an electromotive force from the other end portion toward one end portion is configured by a conductor, and one end portion in the longitudinal direction of the electromotive body is the other end of the adjacent conductor. The thermoelectric conversion element according to claim 4, wherein the thermoelectric conversion element is connected to the end portion to form a folded shape. The electromotive body in which a current flows from the other end portion to the one end portion is composed of a conductor ,
The thermoelectric conversion element according to claim 4, wherein one end portion of the electromotive body in the longitudinal direction is connected to an end portion of the conductor to form a spiral shape. The plurality of electromotive bodies are connected in series by a conductor ,
Electromotive force generation efficiency of the photovoltaic body, the thermoelectric conversion element according to claim 1, characterized in that different electromotive force generation efficiency of the conductor. The thermoelectric conversion element according to any one of claims 5 to 7, wherein a width of the conductor in a stretching direction is narrower than a width of the plurality of electromotive bodies in a stretching direction. The thermoelectric conversion element according to any one of claims 5 to 8 , wherein the conductor includes a material having a smaller spin-orbit interaction than the plurality of electromotive bodies. The thermoelectric conversion element according to claim 5 , wherein a barrier layer is provided between the conductor and the magnetic body.

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