JPH09107130A - Thermoelectric conversion device and its manufacturing method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an efficient manufacturing method of a thermoelectric conversion device by improving the performance of the thermoelectric conversion device and at the same time improving the shock resistance at the time of machining and after forming a module which has been a problem in a thermoelectric material. SOLUTION: A first thin film 11, a first insulation substrate 7, a second thin film 12, and a second insulation substrate 8 form a multilayer structure and the first thin film 11 and the second thin film 12 are electrically connected in series by a first electrode formed on the end face of the first insulation substrate 7 and a second electrode formed on the end face of a second insulation substrate 8.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a thermoelectric conversion element used in a cooling device, a power generation device, a waste heat recovery device, etc., and a method for manufacturing the thermoelectric conversion device.

[0002]

2. Description of the Related Art Thermoelectric cooling elements and thermoelectric power generating elements are generically called thermoelectric conversion elements, which are solid elements of mutual conversion between heat and electricity without moving parts. This element forms an electric circuit by joining dissimilar metals at two points, and when a direct current is applied, heat is generated at one junction and heat absorption occurs at the other end, and one junction is heated and the other is cooled. Then, a thermoelectric power generation phenomenon in which an open circuit voltage depending on the temperature is generated between the open terminals reversibly occurs.

FIG. 9 shows the basic structure of a thermoelectric conversion element having a structure called π type. Various thermoelectric materials have been considered according to the operating temperature range, but P-type semiconductors and N-type semiconductors are basically used from the viewpoint of performance. The P-type semiconductor and the N-type semiconductor are subjected to steps such as composition adjustment, mixing, firing, and heat treatment to form a bulk, which is cut into a predetermined size to produce a P-type chip 1 and an N-type chip 2, respectively. It The P-type chip 1 and the N-type chip 2 are alternately connected in series by soldering via the electrodes 3 to form one unit. In addition, one thermoelectric conversion element can be formed by connecting a plurality of units in parallel according to the electrode connection method. Usually, the electric insulating plate 4 is installed so as to cover the upper and lower electrode surfaces, and a heat exchanger (not shown) is installed on each of the electric insulating plates 4,
The performance is improved by reducing the temperature difference between high temperature and low temperature of the element. When this is used as a thermoelectric cooling element, if a negative voltage is applied to the P-side terminal 5 and a positive voltage is applied to the N-side terminal 6, the electrode surface on the upper surface of each unit becomes the heat absorbing surface and the electrode surface on the lower surface of each unit becomes the heat generating surface. .

[0004]

The thermoelectric conversion element is a solid energy conversion element, and has the advantages that it is vibration-free, noise-free, maintenance-free, and does not require a refrigerant such as CFCs that affects the global environment. However, if cooling is taken as an example, its efficiency is lower than that of the vapor compression refrigeration cycle that is predominant in air conditioners and refrigerators, so far the applications have been small dehumidifiers, portable refrigerators, electronic devices and space equipment. Limited to special applications such as cooling. Therefore, although steady efforts have been made to develop thermoelectric materials to improve efficiency, no significant progress has been seen. The performance of the thermoelectric material is represented by an index called the performance index Z, and the performance of the thermoelectric conversion element improves as the performance index Z increases.

FIG. 10 shows the relationship between the temperature and the figure of merit Z of various representative thermoelectric materials (Kinichi Uemura, Isao Nishida: "Thermoelectric Semiconductors and Their Applications", 1988, p.36). FIG. 10 (a)
This is a case of the P type, and FIG. 10B is a case of the N type. These are all bulk material data, but as shown in the figure, there is an optimum operating temperature range depending on the material, and the temperature level of general air conditioners and refrigerators (about 30
If used as a cooling element at 0K), Bi, Te, S
Compound materials of chalcogenide materials such as b, Se, etc. are most suitable. The performance index Z in this case is 2.5 × 10 ⁻³ (1
/ K), and the dimensionless figure of merit ZT obtained by multiplying this by the operating temperature is currently ZT≈1 for bulk materials including materials mainly used for thermoelectric power generation at high temperatures. With such a performance index, when it is applied to, for example, a home-use refrigerator / freezer, the efficiency is very poor as compared with the compression type refrigeration cycle. For example, in the case of the compression type, the coefficient of performance COP (Coef
ficient of Performance) is about 1.0, but in the case of a thermoelectric conversion element, COP is about 0.2 to 0.3. For this reason, thermoelectric conversion elements have not been popularized in general, although they have great features such as noise-free and vibration-free.

Further, Bi-T normally used for cooling
Chalcogenide-based materials such as e-based materials have a strong cleavability, and the conventional manufacturing method has a problem that cracking occurs when the ingot is cut into chips and the yield is poor. Further, for the same reason, even when modularized into a product, there is a problem that the product has a problem that it is weak against impact and has a problem in commercial property.

By the way, recently, regarding the crystal material of Bi ₂ Te ₃ , the theoretical consideration that the dimensionless figure of merit ZT reaches about 7 times that of the bulk material due to the two-dimensional quantum well structure by the superlattice (LDHicks, "Effect of quantum- well structures
on the thermoelectric figure of merit ", 1994), in which the interaction between electrons and phonons is due to the effect of reducing phonon thermal conductivity due to phonon scattering at the superlattice interface and the effect of confining electrons in the quantum well. The main factor is the decrease in the electric conductivity.The calculation results of the thickness of the unit cell layer and the dimensionless figure of merit ZT according to this document are shown in Fig. 11. Crystal orientation of Bi ₂ Te _{3 in} the current direction. Depending on the result, for example, the basic translation vector a ₀ −b ₀
On the surface, the effect appears when the film thickness is 40 Å or less,
It is shown that, on the a ₀ -c ₀ plane, a figure of merit Z that is about 7 times that of the bulk can be obtained by thinning the film to about 10 Å.

The superlattice structure is composed of, for example, a quantum well laser and has been put to practical use. However, it is formed in a minute portion of a laser light oscillation element.
Realized by ultra-precision film formation by (Molecular Beam Epitaxy), it is produced as a product. However, in order to realize this at an industrially applicable level as an element structure of a power device such as a thermoelectric conversion element, it is necessary to form a superlattice in a considerable volume and at high speed.
It can be easily predicted that equipment such as MBE cannot be used at the current technical level.

Therefore, from the principle of improving the figure of merit, it is considered that the same effect can be obtained even with a single thin film. Therefore, the thermoelectric conversion element and the manufacturing method thereof according to the present invention are improved in thermoelectric conversion efficiency and the conventional method. It is an object of the present invention to solve the problem of cracking at the time of chipping (cutting) and to provide an efficient manufacturing method.

[0010]

In order to achieve the above-mentioned object, a thermoelectric conversion element according to claim 1 of the present invention is a first thermoelectric conversion element.
A first semiconductor thin film formed between the first insulating substrate and the second insulating substrate, and a second insulating substrate in a laminated structure in which the insulating substrate and the second insulating substrate are alternately laminated. A second semiconductor thin film formed between the substrate and the first insulating substrate;
The first insulating substrate is formed through an end surface of the first insulating substrate, and the first insulating substrate is formed.
A first electrode for electrically connecting the semiconductor thin film and the second semiconductor thin film, and an end face of the second insulating substrate facing each other with an end face on which the first electrode is formed, A second electrode for electrically connecting the second semiconductor thin film and the first semiconductor thin film is provided, and the first semiconductor thin film and the second semiconductor thin film are electrically connected in series. It is characterized by

According to a second aspect of the present invention, in addition to the means constituting the thermoelectric conversion element according to the first aspect, the first insulating substrate and the second insulating substrate are flexible. A film, wherein a first semiconductor thin film and a second semiconductor thin film are connected in series by a first electrode or a second electrode across the first insulating substrate or the second insulating substrate. It is characterized in that it has a structure in which it is wound in an overlapping state.

A method of manufacturing a thermoelectric conversion element according to a third aspect of the present invention comprises a step of forming a first semiconductor thin film on the front surface of a first insulating substrate and a second semiconductor thin film on the rear surface thereof, and A step of forming a first electrode for electrically connecting the first semiconductor thin film and the second semiconductor thin film on one end surface of the first insulating substrate; and a second step of stacking the first electrode on the first insulating substrate. After the step of forming a second electrode electrically connecting the front surface and the back surface of the second insulating substrate to the end surfaces of the insulating substrate facing each other with the end surface on which the first electrode is formed, It is characterized in that the first insulating substrate and the second insulating substrate are superposed and wound.

A method of manufacturing a thermoelectric conversion element according to a fourth aspect of the present invention comprises a step of forming a first semiconductor thin film on a surface of a first insulating substrate, and an end face on one side of the first insulating substrate.
A step of forming a first electrode for electrically connecting the first semiconductor thin film and a back surface of the first insulating substrate, and a surface of a second insulating substrate laminated on the first insulating substrate, A step of forming a second semiconductor thin film, and a step of forming the second insulating substrate,
After the step of forming a second electrode for electrically connecting the second semiconductor thin film and the back surface of the second insulating substrate on the end surfaces facing each other with the end surface on which the first electrode is formed, It is characterized in that the first insulating substrate and the second insulating substrate are superposed and wound.

According to a fifth aspect of the present invention, there is provided a method for producing a thermoelectric conversion element, which comprises, in addition to the steps constituting the method for producing a thermoelectric conversion element according to the third or fourth aspect, a first semiconductor thin film and Second semiconductor thin film, first electrode and second
And the second insulating substrate are superposed on each other and wound up after the step of intermittently forming the electrodes of a predetermined length at predetermined intervals.

According to a sixth aspect of the present invention, there is provided a method for producing a thermoelectric conversion element according to any one of the third to fifth aspects, in which a step of forming a semiconductor thin film is performed. The method is characterized by comprising a step of applying heat treatment after applying or spraying a solution in which a P-type semiconductor material or an N-type semiconductor material is dissolved or dispersed in advance to the first insulating substrate or the second insulating substrate. .

A method of manufacturing a thermoelectric conversion element according to a seventh aspect of the present invention is the first method in addition to the steps constituting the method of manufacturing a thermoelectric conversion element according to any one of the third to sixth aspects. The second electrode and the second electrode are made of a low-melting metal, and the first insulating substrate and the second insulating substrate are stacked by a stacking roller heated to a temperature equal to or higher than the melting point of the low-melting metal. Is characterized by.

[0017]

FIG. 1 shows the basic structure of a thermoelectric conversion element according to an embodiment of the present invention. FIG. 1A is a cross-sectional view in the direction crossing the heat absorbing surface and the heat generating surface, and FIG.
It is a center sectional view of a direction parallel to a heat absorption surface and a heat generation surface. Unless otherwise specified, the description will be made with the thermoelectric cooling element. The first insulating substrate 7 and the second insulating substrate 8 which are flexible films are, for example, a polymer material such as polyimide. The first thin film 11 and the second thin film 12 respectively have a first
The insulating substrate 7 and the second insulating substrate 8 are alternately sandwiched and laminated. The first thin film 11 is an N-type semiconductor material and the second thin film 12 is a P-type semiconductor material. If the purpose is cooling near room temperature, the N-type and P-type semiconductor materials are currently composed mainly of a combination of chalcogenide materials such as Bi, Sb, Te, and Se as shown in FIG. The highest performance. However, FIG. 10 is an example of what has been studied so far, and there is a sufficient possibility that a new high-performance material will be discovered in the future.

The first thin film 11 and the second thin film 12 are
Are electrically connected by the first electrode 9 or the second electrode 10 formed via the end surface of the insulating substrate 7 or the second insulating substrate 8. The first thin film 11 and the second thin film 12 are connected in series by a predetermined number by the first electrode 9 and the second electrode 10. In the present embodiment, the first
Directly on the insulating substrate 7 and the second insulating substrate 8 of
And a second electrode is formed. However, the first thin film 11 and the second thin film 12 formed on the insulating substrate may be electrically connected to each other. The second thin film 12 may be covered with the end surface of the first insulating substrate 7. When a positive voltage is applied to the N-type first thin film 11 side and a negative voltage is applied to the P-type second thin film 12 side, the first electrode 9 in which a current flows from the N-type to the P-type due to the so-called Peltier effect. Heat is absorbed, and heat is generated in the second electrode 10 in which a current flows from P type to N type, and the heat absorbing surface 13
Thus, the heating surface 14 is formed.

In this structure, since a current flows in the direction of the thin film, the electric resistance is basically large, and a large voltage is required to obtain a current for producing sufficient capacity. In order to avoid this, it is necessary to make the dimension a of the thin film in the figure as large as possible and the dimension b as small as possible.

In this structure, since the thermoelectric material is a thin film, a substrate is inevitable. This substrate becomes a factor of heat leakage from the heat generating surface to the heat absorbing surface, and thus becomes a factor that deteriorates the performance as a thermoelectric conversion element. Considering this heat conduction, it is desirable that the substrate be as thin as possible and that the substrate material have a small thermal conductivity.

In the thermoelectric conversion element according to the present invention, an electric current flows in the film direction of the thermoelectric material thin film, and if it is considered as a thermoelectric cooling element, the first electrode and the second electrode provided on the end surface of the insulating substrate are heat generating portions or It becomes an endothermic part. The structure in which these are stacked is a multilayer structure consisting of an insulating substrate and a thermoelectric material thin film,
The heat generating portion and the heat absorbing portion are separated by sandwiching the multilayer structure. That is, it provides a structure in which a heat generating surface and a heat absorbing surface are formed. By installing a heat exchanger similar to the conventional case, it is possible to efficiently cool a gas or a liquid.
Further, since the insulating substrate is flexible, it has a shock absorbing property.

Next, FIG. 2 shows a first embodiment of a method for manufacturing a thermoelectric conversion element according to the present invention. Although the present embodiment includes a vacuum process, the basic structure and operation of the vacuum equipment such as the vacuum chamber, the vacuum pump, the switching valve, etc. are known and will not be described.

A flexible first insulating substrate 7 and a flexible second insulating substrate 8 are wound around the first roller 15 and the second roller 16, respectively. The roller around which the substrate material is wound is placed in a vacuum device, and the substrate material is sufficiently outgassed. The first insulating substrate 7 drawn out from the first roller 15 and the second insulating substrate 8 drawn out from the second roller 16 are taken up by the take-up roller 17 in an overlapping manner. In the meantime, the following thin film fabrication, electrode formation,
A process such as heat treatment is performed.

The thin film is produced by a single vapor deposition machine using an alloy material, a multi-source vapor deposition machine capable of vapor depositing a single material simultaneously or in multiple layers,
Various methods such as sputtering and CVD can be considered. FIG. 2 shows the case of multi-source simultaneous vapor deposition. When depositing a P-type semiconductor containing Bi, Sb, and Te as a first thin film on the surface of the first insulating substrate 7, for example, an electron gun 21 is used as a vapor deposition heat source, and the respective strengths are different for each material. By adjusting to the corresponding appropriate conditions, a film having a predetermined composition is formed. Then, a second thin film such as Bi, Sb, T is formed on the back surface of the first insulating substrate 7 by the same method.
An N-type semiconductor containing e as a component is formed. Note that the second insulating substrate 8 is not formed.

Here, the first thin film and the second thin film are opened for a certain period of time by opening the first shutter 24 and the second shutter 24a so that the first thin film and the second thin film have a predetermined length a and are formed intermittently. The timer is controlled so that it will be closed for a certain time. At this time, since the first thin film 11 and the second thin film 12 are formed facing each other on the front and back of the first insulating substrate 7, the moving speed of the first insulating substrate 7 and the first thin film 11 The shift amount of the opening / closing timing of the first shutter 24 and the second shutter 24a is calculated in advance and controlled from the relationship between the vapor deposition positions of the second thin film 12 and the second thin film 12.

Next, the first insulating substrate 7 and the second insulating substrate 8
3 shows a method of forming an electrode connecting the first thin film 11 and the second thin film 12 with the first insulating substrate 7 as an example. This is paste solder, solder application roller 25
The paste solder 22 is continuously supplied from the solder supply pipe 18 to the roller surfaces of the pair of solder application rollers 25 which are installed on the front and back of the insulating substrate 7 and contact the front and back of the insulating substrate 7, respectively. The insulating substrate 7 is coated so that the front surface and the back surface thereof are electrically connected via the end faces. It is also possible to apply with a brush-like material (not shown) other than the roller.

For intermittent formation of the electrodes, the solder coating roller 25 or a brush (not shown) is intermittently formed on the insulating substrate 7.
This can be achieved by moving away from. However, the first electrode 9
Must be formed so as to overlap the same portion as the first thin film 11 and the second thin film 12 that are formed intermittently. Therefore, the timing for separating the solder coating roller 25 from the insulating substrate 7 depends on the moving speed of the insulating substrate 7 in FIG.
Also, the shift amount of the timing of the movement of the solder coating roller 25 is calculated and controlled from the second thin film forming position and the electrode forming position in advance. Alternatively, immediately before the solder coating roller 25, it is possible to detect the presence or absence of thin film vapor deposition by utilizing the difference in the reflectance of the substrate and to control the movement of the solder coating roller 25 accordingly.

Whether the electrode is formed before forming the thin film or after forming the thin film, the first thin film 11 is formed.
The second thin film 12 can be electrically connected to the second thin film 12. However, if the gas released from the solder in the vacuum device is taken into consideration, this step is performed before the first insulating substrate 7 is wound around the first roller 15. Alternatively, it is desirable to perform after forming the first thin film 11 and the second thin film 12 as described above.

The second electrode 10 is formed on the second insulating substrate 8 by the same method as described above. In this case, a thin film is not formed on the second insulating substrate 8 and the second electrode 10
Is directly coated on the second insulating substrate 8. The second electrode 10 is formed on the end face opposite to the surface on which the first electrode 9 is formed. However, the second electrode 10 needs to be formed so as to overlap the same portions as the first thin film 11, the second thin film 12, and the first electrode 9 which are intermittently formed. Therefore, as in the case of forming the first electrode 9, the timing of separating the solder coating roller from the second insulating substrate 8 is the first and second timings measured from the position of the overlapping roller 30 in FIG.
The amount of shift in the timing of movement of the solder coating roller 25 is calculated and controlled in advance from the difference in the distance between the electrode forming process positions and the substrate transport speed.

The first insulating substrate 7 and the second insulating substrate 8 on which the thin film and the electrodes are formed are superposed by the superposing roller 30 shown in FIG. At this time, a portion of the width of the superposing roller 30 corresponding to the width of the first and second electrodes is heated by the lamp heater 23 to a temperature higher than at least the melting point of the electrode material solder. Specifically, only the portion of the superposing roller 30 where the temperature is desired to be high (hatched portion in the figure) may be subjected to heat treatment such as black coating. At this time, since the superimposing roller 30 comes into contact with the molten solder, it is necessary to use a material whose roller surface is not wettable by solder. Thereby, the first electrode 9 and the second electrode 1
Solder, which is a material of No. 0, melts, the adhesion with the thin film material is improved, and the contact resistance can be reduced.

By the formation of such an intermittent thin film and electrode, and the winding after superposition, the first thin film 11 and the second thin film 12 having a predetermined length a are replaced by the first electrode 9
Alternatively, a series circuit unit electrically connected in series via the second electrode 10 is formed.

When the voltage applied to the thermoelectric cooling element is fixed, the current having the highest efficiency or the highest capacity cannot be passed only by the series circuit including the pair of the first thin film 11 and the second thin film 12. However, by forming a series circuit unit composed of a plurality of series circuits by the above method,
Appropriate current can be applied.

Further, after the series circuit unit is formed, the first and second insulating substrates are wound up without forming electrodes and thin films for a predetermined length, and then the series circuit unit is formed again. Then, a plurality of series circuit units can be continuously formed by repeating these steps.
FIG. 5 shows a shape of a thermoelectric conversion element in which a plurality of series circuit units are formed in an arc shape and wound in a circle. The black portion in the figure is one series circuit unit of length a, and as shown in the enlarged view, the thin film 11 and the thin film 12 are insulated substrates 7 and 8 respectively.
It is sandwiched between and is connected in series by electrodes (not shown) alternately on the front side and the back side of the paper.

Next, FIG. 6 shows a second embodiment of the method for manufacturing a thermoelectric conversion element according to the present invention. This embodiment is different from the first embodiment only in the steps up to electrode formation, and the heat treatment step is the same as in the first embodiment. The film forming method is similar to that of the first embodiment, and the difference from the first embodiment of FIG. 2 is that the first thin film 11 is formed on the surface of the first insulating substrate 7.
That is, the second thin film 12 is formed on the surface of the second insulating substrate 8.

FIG. 7 shows an embodiment in which a method for realizing the formation of a thin film by a method other than the vacuum process is performed on the first insulating substrate 7. First on the surface of the first insulating substrate 7.
As a thin film of P, for example, P containing Bi, Sb, and Te as components
-Type semiconductor is formed, and a second thin film such as B is formed on the back surface.
When an N-type semiconductor containing i, Sb, and Te as components is formed into a film, powders of a single substance are dissolved or dispersed in a suitable solvent in advance at predetermined composition ratios, respectively, and these are used as the first raw material liquid 2
6 and the second raw material liquid 27. The first raw material liquid 26 is continuously supplied to the roller surface of the first raw material liquid coating roller 28, and the second raw material liquid 27 is continuously supplied to the second raw material liquid coating roller 29. A film of the raw material liquid 26 and the second raw material liquid 27 is formed. It is also possible to apply with a brush-like material (not shown) other than the roller. The operation corresponding to the intermittent formation of the thin film described with reference to FIG. 2 can be realized by the raw material liquid coating roller 28 and the raw material liquid coating roller 29, or the intermittent vertical movement of the brush (not shown).

FIG. 8 shows another embodiment in which the method of forming the thin film by a method other than the vacuum process is performed on the first insulating substrate 7. First nozzle 31 and second nozzle 32
Are provided on the front side and the back side of the insulating substrate 7 so as to face each other, and the first raw material liquid 26 is sprayed from the first nozzle 31 and the second raw material liquid 27 is sprayed from the second nozzle 32. And a second thin film can be formed. The operation corresponding to the intermittent formation of the thin film in the description of FIG. 2 is such that the spraying from the first nozzle 31 and the second nozzle 32 is intermittent, or the spraying onto the insulating substrate 7 is controlled by a shutter (not shown). It can be realized by doing.

In the thin film forming method shown in FIGS. 7 and 8, it is necessary to remove the solvent components and combine the materials by heat treatment after these steps. Before the electrode forming step shown in FIG. Need to pass. The heating temperature is, for example, 500 to 60 for materials such as Bi and Te.
Since the melting point is about 0 ° C., a temperature higher than that is sufficient. The boiling point of a general solvent is not so high, and the solvent component can be removed simultaneously with the heat treatment of the material.

As a result, the above-described thin film forming method uses a process at atmospheric pressure to apply or spray a solution in which the first or second thermoelectric material is dissolved or dispersed to adhere it to the substrate and then heat it. As a result, only the solution evaporates, and only the thermoelectric material is formed as a thin film on the substrate.

[0039]

As described above, according to the first aspect of the present invention,
The thermoelectric conversion element described in 1 is an element with a very thin single thin film, and in the direction of such a thin film, the figure of merit is improved by the effect of reducing the thermal conductivity due to phonon scattering at the interface. The present invention provides a thermoelectric conversion element that can be effectively utilized as a power device.

In the thermoelectric conversion element according to the second aspect of the present invention, since the flexible film serving as the substrate has a shock absorbing function, the weakness to the shock which has been a problem in the conventional thermoelectric conversion element is eliminated. It

In the method of manufacturing a thermoelectric conversion element according to the third and fourth aspects of the present invention, the continuous structure of the first and second thin films connected in series is efficiently formed by the continuous process. Further, unlike general film formation on a fixed substrate, since the film is formed while the substrate is moving, the nonuniformity of the film, which would be a problem with the fixed substrate, is mitigated, and a film of good quality can be formed. Become.

The method of manufacturing a thermoelectric conversion element according to a fifth aspect of the present invention can realize a thermoelectric conversion element having a structure in which a plurality of series-connected circuit units are formed in a continuous process, and the conventional P-type, N-type Since it is not a stepwise process of forming, aligning, and soldering the mold, the problem of cracking when cutting an ingot as in the past is solved. Further, since the step of arranging chips is not involved, low cost manufacturing is possible.

The method of manufacturing a thermoelectric conversion element according to claim 6 of the present invention is a process at atmospheric pressure that does not use a vacuum device, and can be manufactured at low cost.

In the method for manufacturing a thermoelectric conversion element according to the seventh aspect of the present invention, since the pressing by the roller and the heating of the necessary portion can be performed at the same time, the adhesion between the electrode and the thin film is improved, and the contact resistance that greatly affects the performance is improved. Can be reduced.

[Brief description of the drawings]

FIG. 1A and FIG. 1B are diagrams showing a basic structure of a thermoelectric conversion element of the present invention.

FIG. 2 is a diagram showing a first embodiment of a method for manufacturing a thermoelectric conversion element according to the present invention.

FIG. 3 is a diagram showing a method of forming an electrode according to the present invention.

FIG. 4 is a diagram showing a method of superimposing an electrode and a thin film according to the present invention.

FIG. 5 is a diagram showing a shape of a thermoelectric conversion element of the present invention.

FIG. 6 is a diagram showing a second embodiment of a method for manufacturing a thermoelectric conversion element according to the present invention.

FIG. 7 is a diagram showing an embodiment of a thin film forming method according to the present invention.

FIG. 8 is a diagram showing another embodiment of the thin film forming method according to the present invention.

FIG. 9 is a diagram showing a basic structure of a conventional thermoelectric conversion element.

10 (a) and (b) are temperature-performance index diagrams of representative thermoelectric materials.

FIG. 11 is a film thickness-dimensionless figure of merit diagram.

[Explanation of symbols]

 1 P-type chip 2 N-type chip 3 Electrode 4 Electrical insulating plate 5 P-side terminal 6 N-side terminal 7 First insulating substrate 8 Second insulating substrate 9 First electrode 10 Second electrode 11 First thin film 12 Second thin film 13 Endothermic surface 14 Exothermic surface 15 First roller 16 Second roller 17 Winding roller 18 Paste solder supply pipe 19 First raw material liquid supply pipe 20 Second raw material liquid supply pipe 21 Electron gun 22 Paste Solder 23 Lamp heater 24 First shutter 24a Second shutter 25 Solder coating roller 26 First raw material liquid 27 Second raw material liquid 28 First raw material liquid coating roller 29 Second raw material liquid coating roller 30 Stacking roller 31 first nozzle 32 second nozzle

Front page continued (72) Inventor Kazuaki Minato 22-22 Nagaike-cho, Abeno-ku, Osaka-shi, Osaka Prefecture Sharp Corporation (72) Inventor Shigeo Harada 22-22 Nagaike-cho, Abeno-ku, Osaka-shi, Osaka Osaka Corporation (72) Inventor Yoshihiro Yamamoto 22-22 Nagaike-cho, Abeno-ku, Osaka-shi, Osaka Prefecture Sharp Corporation (72) In-house Takashi Tomita 22-22 Nagaike-cho, Abeno-ku, Osaka City, Osaka Prefecture

Claims (7)

[Claims] 1. A first semiconductor having a laminated structure in which a first insulating substrate and a second insulating substrate are alternately laminated, the first semiconductor being formed between the first insulating substrate and the second insulating substrate. A thin film, a second semiconductor thin film formed between the second insulating substrate and the first insulating substrate, an end surface of the first insulating substrate, and
A first electrode for electrically connecting the semiconductor thin film and the second semiconductor thin film, and an end face of the second insulating substrate facing each other with an end face on which the first electrode is formed, A second electrode is provided that electrically connects the second semiconductor thin film and the first semiconductor thin film, and the first semiconductor thin film and the second semiconductor thin film are electrically connected in series. A thermoelectric conversion element characterized by the above. 2. The first insulating substrate and the second insulating substrate are flexible films, and the first semiconductor thin film and the second semiconductor thin film are the first insulating substrate or the second insulating thin film. The thermoelectric conversion element according to claim 1, wherein the thermoelectric conversion element has a structure in which the insulating substrate is sandwiched and wound in a state of being connected in series by the first electrode or the second electrode and sandwiching the insulating substrate. 3. A first semiconductor thin film is formed on a front surface of a first insulating substrate and a second semiconductor thin film is formed on a back surface of the first insulating substrate, and the first semiconductor thin film and the first semiconductor thin film are formed on one end surface of the first insulating substrate. Forming a first electrode electrically connecting to the second semiconductor thin film, and facing the end face of the second insulating substrate laminated on the first insulating substrate, on which the first electrode is formed. After forming a second electrode on the end face that electrically connects the front surface and the back surface of the second insulating substrate, the first insulating substrate and the second insulating substrate are superposed,
A method for manufacturing a thermoelectric conversion element, which comprises winding. 4. A first semiconductor thin film is formed on the front surface of a first insulating substrate, and the first semiconductor thin film and the back surface of the first insulating substrate are electrically connected to one end surface of the first insulating substrate. Electrically connecting a first electrode, forming a second semiconductor thin film on the surface of the second insulating substrate laminated on the first insulating substrate, and forming a second semiconductor thin film on the surface of the second insulating substrate. After forming a second electrode for electrically connecting the second semiconductor thin film and the back surface of the second insulating substrate on an end surface opposite to the end surface on which the first electrode is formed, the first insulating film is formed. Stack the substrate and the second insulating substrate,
A method for manufacturing a thermoelectric conversion element, which comprises winding. 5. The first semiconductor thin film and the second semiconductor thin film, and the first electrode and the second electrode are intermittently formed with a predetermined length at a predetermined interval, and The method for manufacturing a thermoelectric conversion element according to claim 3 or 4, wherein the first insulating substrate and the second insulating substrate are stacked and wound. 6. The semiconductor is prepared by applying or spraying a solution in which a P-type semiconductor material or an N-type semiconductor material is dissolved or dispersed in advance onto the first insulating substrate or the second insulating substrate, and then performing heat treatment. A thin film is formed, The manufacturing method of the thermoelectric conversion element of any one of Claim 3 thru | or 5 characterized by the above-mentioned. 7. The first electrode and the second electrode are made of a low melting point metal, and the first insulating substrate and the second electrode are formed by a stacking roller heated to a temperature equal to or higher than the melting point of the low melting point metal. The method for manufacturing a thermoelectric conversion element according to any one of claims 3 to 6, wherein an insulating substrate is superposed.