JPH06338636A - Manufacture of thermoelectric generating element - Google Patents

Abstract

PURPOSE:To provide a method of manufacturing a thermoelectric generating element in which a multitude of thermoplastic couples which are microscopic in size and cannot be fabricated by a conventional machining method are integrated on a narrow region, so as to develop a generating element usable for a small-sized electronic device such as a wrist watch. CONSTITUTION:A multitude of microscopic holes are opened in a substrate 10, such as a silicon wafer and a photosensitive ceramic substrate, using an anisotropic etching technique, two kinds of first and second thermoelectric materials 50 and 51 are formed in the holes by a plating method using first and second metal film electrodes 30 and 21, the two kinds of the thermoelectric materials adjacent to each other are connected to each other, a multitude of thermoelectric couples 70 are formed and moreover, a thermoelectric element is formed by connecting the thermoelectric couples in series. Thereby, the multitude of the microscopic thermoelectric couples can be integrated on a narrow region and a small-sized thermoelectric generating element, whose integration density and output density are improved and higher than those of a conventional thermoelectric generating element, can be manufactured.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method of manufacturing a thermoelectric power generating element using a thermoelectric material, and more particularly to a method of manufacturing a power generating element combining a substrate microfabrication technique and a thermoelectric material plating technique.

[0002]

2. Description of the Related Art Thermocouples generate a voltage by applying a temperature difference across their ends. Thermoelectric power generation attempts to utilize this voltage as electric energy.

Thermoelectric power generation is a method of directly converting thermal energy into electric energy, including the use of waste heat.
It has received a great deal of attention as an effective use of heat energy.

Further, since the structure is simple, it is advantageous in miniaturization as compared with other generators, and it does not wear out like an oxidation-reduction battery, and there is no problem of electrolyte leakage. The application to such portable electronic devices is drawing attention.

The general structure of a thermoelectric power generating element is shown in the perspective view of FIG. In the thermoelectric generator having a plate-like structure as a whole, many thermocouples 70 using p-type and n-type thermoelectric materials are arranged and connected in series.

A hot junction 71 and a cold junction 72 of the thermocouple 70.
Are located on the front and back of the plate-shaped thermoelectric generator,
Power is generated by the temperature difference between the front and back.

By the way, even in the case of the BiTe system, which has undergone a lot of research and has a high figure of merit, the current output voltage is about 400 μV / ° C. per pair.

Considering the application to a portable electronic device, since it is used near room temperature, a temperature difference cannot be expected so much.
That is, even if a temperature difference of 5 ° C. is obtained, 500 thermocouples are required to obtain a voltage of 1V.

There is no problem if the power generating element is increased in size.
00 thermocouples as big as button batteries, eg 1
Integration in the cm square is a very difficult problem.

Thermoelectric materials currently used for thermoelectric power generation are mainly produced by a sintering method. There is also a method of cutting and joining them one by one as thermocouples, and a more advanced method is, for example, JP-A-63-20880.
There is a manufacturing method disclosed in the publication.

The manufacturing method described in this publication is a method in which thin plates of p-type and n-type sintered materials are prepared, laminated with an insulating material, further thinly cut, and grooves are formed.

[0012] These methods rely on mechanical processing, and the processing in the minute area is limited. Further, since most of the sintered thermoelectric materials are very brittle, it is necessary to take great care not only in cutting but also in handling after cutting, which naturally lowers the production yield.

From these facts, in the conventional method using machining, it is considered that it is a common sense to handle a material having a thickness and a width of about 1 mm at most. The logarithm is only 50 pairs.

As another method, a method of forming a thermoelectric material as a thin film by using a film forming technique such as a vacuum vapor deposition method and then miniaturizing it by an etching method to form a small thermocouple is conceivable.

Although it is easy to make small pairs by this method, it is difficult to integrate many pairs in the end because they are arranged in a plane, and it is difficult to arrange hot junctions and cold junctions. . Further, since it is a thin film, the resistance value increases, the current value decreases, and the efficiency decreases.

[0016]

As described above, both the conventional machining method and the method for etching a vacuum deposited film produce a thermoelectric power generating element by integrating many thermocouples in a minute area. Is difficult. That is, since the logarithm cannot be increased by the conventional manufacturing method, it is impossible to make a small power generating element having a sufficient output.

Therefore, the object of the present invention is to solve the above-mentioned problems and to manufacture a thermoelectric power generation element which can obtain a sufficient output as a power generator even if it is small, so that a large number of thermocouples can be integrated in a minute area. For example, 500 in 1 cm square
It is to provide a method for manufacturing a thermoelectric power generation element capable of forming the above pairs.

[0018]

In order to achieve the above object, the present invention employs the manufacturing method described below.

The method of manufacturing a thermoelectric power generating element of the present invention comprises a step of etching a first hole penetrating from the front surface of the substrate to the back surface of the substrate, and a first metal film electrode formed on the back surface of the substrate. Forming a first thermoelectric body made of a first thermoelectric material by a plating method so as to fill the first hole by using the method described above;
Of the second metal film electrode formed on the front surface of the substrate by etching, forming a second hole penetrating from the back surface of the substrate to the front surface of the substrate so as to be arranged in a matrix with the holes of Forming a second thermoelectric body made of a second thermoelectric material so as to fill the second hole by a plating method; and patterning the second metal film electrode to make the first thermoelectric body and the second thermoelectric body adjacent to each other. The third thermocouple was formed on the back side of the substrate by forming a hot junction by connecting the thermoelectric body of
After forming cold junctions by patterning the metal film electrodes of, and connecting all the thermocouples in series, a base made of a metal plate is attached to the back surface of the substrate so as to contact the cold junctions of all the thermocouples. It has a process of

The method of manufacturing a thermoelectric power generating element according to the present invention comprises the steps of forming first metal film electrodes and second metal film electrodes, which are alternately arranged on the back surface of the substrate, and from the front surface of the substrate to the substrate. Forming a plating hole penetrating to the back surface by etching, and plating a first thermoelectric material made of a first thermoelectric material so as to fill half of the plating hole using the first metal film electrode And a second metal film electrode is used to alternately line up with the first thermoelectric body so that the whole substrate is arranged in a matrix with the first thermoelectric body so that the remaining half of the plating holes are filled. And a step of forming a second thermoelectric body made of a second thermoelectric material by a plating method, and patterning a metal film newly formed on the front surface and the back surface of the substrate, and The main part of the board is connected to the thermoelectric body of 2. After connecting all the thermocouples in series by forming hot junctions on the surface and cold junctions on the backside of the board, make sure that the base plate made of a metal plate on the backside of the board contacts the cold junctions of all thermocouples. And a step of pasting.

[0021]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A method for manufacturing a thermoelectric power generating element in an embodiment of the present invention will be described in detail below with reference to the drawings.

[0022]

Embodiment 1 A first embodiment of the present invention is shown in FIGS.
An explanation will be given using (h). FIG. 1 is a cross-sectional view of a main part of a method for manufacturing a thermoelectric power generation element according to the present invention.

For manufacturing, a low-doped silicon wafer having a (100) orientation and a thickness of about 200 μm and having both sides polished is used as the substrate 10.

First, as shown in FIG. 1A, a gold (Au) film having a film thickness of about 500 nm is formed on the front surface 11 of the substrate by a vacuum evaporation method. After that, a large number of rectangular patterns are formed on the entire surface of the gold film with a predetermined size and intervals using a photoresist.

This photoresist pattern (not shown)
Is used as an etching mask to etch the gold film as shown in FIG. 1A to form a first mask 20 having the same pattern shape as the photoresist.

At this time, for etching the gold film for forming the first mask 20, a mixed aqueous solution of iodine and potassium iodide (hereinafter referred to as potassium iodine iodide solution) is used as an etchant. After that, the photoresist is stripped and removed with a dedicated stripping solution.

Continuing on, the back surface 12 of the substrate also has about 500
A gold film having a thickness of nm is formed by a vacuum vapor deposition method, and the first metal film electrode 30 is manufactured. A Teflon-based polymer film (not shown) for protection is formed on the first metal film electrode 30 by spin coating.

The manufactured first mask 20 is used as a mask for etching, and as shown in FIG.
The exposed silicon wafer of 0 is removed by an etching method to form a first hole 40.

The substrate 10 is etched by a so-called anisotropic etching method in which a strong alkaline aqueous solution such as a potassium hydroxide (KOH) aqueous solution or a hydrazine-based aqueous solution is used for etching.

When a (100) -oriented silicon wafer is used as the substrate 10, a (111) plane appears in the etching cross section and the cross-sectional shape is linearly etched, and the angle is always about 54 °, and the reproducibility is high. Good.

The etching is performed until it penetrates the substrate 10, that is, until the first metal film electrode 30 of the gold film on the back surface 12 of the substrate appears. In this case, since the gold film is insoluble in the etchant, it remains on the back surface 12 of the substrate.

Subsequently, as shown in FIG. 1C, the first thermoelectric material 50 is manufactured by filling the first holes 40 with a first thermoelectric material by using a plating method.

The first thermoelectric body 50 is Bi, which is an n-type semiconductor.
TeSe alloy is used as the material. As the electrolyte, B
An acidic solution containing i (NO ₃ ), TeO ₂ , and SeO ₂ is used.

The first metal film electrode 30 on the back surface 12 of the substrate is used as a cathode, and a Pt plate is used as an anode, and a constant voltage is applied between both electrodes. BiTe by applying a voltage around 0.5V
The Se alloy is deposited on the first metal film electrode 30.

In this case, since the outer surface of the first metal film electrode 30 is protected by the polymer film as described above, Bi
The TeSe alloy can be deposited only in the first holes 40 to form the first thermoelectric body 50.

Further, since the silicon wafer which is exposed but has a low impurity doping amount is used, the resistance value is much higher than that of the gold film and no leakage current flows.

In the plating method, since the amount of deposition is determined by the amount of charge calculated from the current consumption during electrolysis, it is easy to stop the deposition by the depth of the first hole 40 each time by measuring the amount of charge. Is.

Further, the alloy composition can be changed by changing the ion concentration of Bi, Te, Se in the electrolytic solution or the applied voltage, and the material having the required output voltage or resistance value can be selected by setting these conditions. select.

After the plating for forming the first thermoelectric body 50 is completed, the polymer film is peeled and removed with an organic solvent such as toluene.

Next, as shown in FIG. 1 (d), a gold film is newly formed on the front surface 11 of the substrate to a thickness of 500 nm by the vacuum deposition method to form the second metal film electrode 21.

In this case, the gold film used as the first mask 20 is removed by etching with potassium iodine iodide solution in advance, but there is no problem if it is left. Also here, a Teflon-based polymer film (not shown) for protection is formed on the upper surface of the second metal film electrode 21 by spin coating.

Then, the first metal film electrode 30 on the rear surface 12 of the substrate is, as described in the manufacture of the first mask 20,
Use the photoresist as a mask for etching,
The second mask 31 is formed by patterning into a predetermined shape by an etching method using a potassium iodine iodide solution.

The second mask 31 is also used as an etching mask for the silicon wafer of the remaining substrate 10, and the same method as that for forming the first hole 40 is shown in FIG. 1 (e). Such a second hole 41 is formed.

That is, a so-called anisotropic etching method, in which a strong alkaline aqueous solution such as a KOH aqueous solution or a hydrazine-based aqueous solution is used for etching, is used to penetrate the substrate 10, that is, the gold film on the front surface 11 of the substrate. Second
Etching is performed until the metal film electrode 21 of 1.

In this case, the second mask 31 is formed to be slightly larger than the size of the first thermoelectric body 50 in contact with the second mask 31 in the patterning process described above. Therefore, some silicon layer of the material of the substrate 10 remains between the second hole 41 and the first thermoelectric body 50, and there is no spatially continuous portion between them.

The remaining of the silicon layer is the step described later, and the second thermoelectric body 5 formed in the second hole 41 is left.
This is to prevent the first thermoelectric body 50 from coming into contact with each other and electrically short-circuiting.

Subsequently, as shown in FIG. 1F, the second thermoelectric material 51 is prepared by filling the second hole 41 with the second thermoelectric material by using the plating method.

The first thermoelectric body 50 already manufactured,
The second thermoelectric element 51 constitutes a thermocouple in the element.

For the second thermoelectric element 51, a BiSbTe alloy which is a p-type semiconductor is used as a material. Then, as the electrolytic solution, Bi (NO ₃ ), SbCl ₃ , TeO _{2 are used.}
An acidic solution containing is used.

Similar to the case of manufacturing the first thermoelectric body 50, this time, the second metal film electrode 21 formed on the front surface 11 of the substrate is used as the cathode, and the Pt plate is used as the anode. A constant voltage is applied between the electrodes. The BiSbTe alloy is deposited on the second metal film electrode 21 by applying a voltage in the vicinity of 0.5 V, and the second thermoelectric body 51 is manufactured.

Since the outer surface of the second metal film electrode 21 is covered with the polymer film as described above, the second thermoelectric element 5
1 is deposited only in the second hole 41, and is also controlled by the reaction charge amount so as to be deposited only in the thickness of the substrate 10.

The electrical characteristics of the deposits are controlled by changing the plating bath composition, electrolysis voltage, and the like. After the plating process, the polymer film is peeled and removed with an organic solvent such as toluene.

Furthermore, a gold film is newly formed on the back surface 12 of the substrate.
The third metal film electrode 32 is formed with a film thickness of 00 nm by a vacuum evaporation method. The second mask 31 is dissolved by etching and then vacuum deposition is performed, but there is no problem even if it is left.

Then, the third metal film electrode 32 on the back surface 12 of the substrate and the second metal film electrode 21 on the front surface 11 of the substrate use photoresist as a mask for etching, and potassium iodine iodide is used. Patterning is performed by an etching method using a liquid, and the first thermoelectric body 50 and the second thermoelectric body 51 are alternately connected in series as shown in FIG.

Although a horizontal cross-sectional view is shown in FIG. 1, the actual element has a rectangular shape, and the thermoelectric bodies closest to the sides of the square in the vertical direction are also the first metal film electrodes. 30 or the second metal film electrode 21 so that all the thermoelectric elements are connected in series as a whole.

The metal film electrodes located at both ends of the thermoelectric elements connected in series are used as extraction electrodes for extracting the output to the outside. An example of the shape of the metal film electrode is shown in FIG. 2, which is a plan view of the element. By the way, the number of thermocouples 70 of the element shown in FIG. 2 is 22 pairs.

Finally, a base 60 having a size that is substantially the same as or slightly larger than that of the substrate 10 at the beginning of the process is adhered to the third metal film electrode 32.

The base 60 is made of a metal such as a copper plate, an aluminum plate, and a stainless plate, which has good heat conductivity.

In this case, the surface of the base 60 is oxidized so that the third metal film electrode 32 is not short-circuited.
Alternatively, an insulator is used as the base 60 or the third metal film electrode 32.
The third metal film electrode 32 and the base 6 must be coated on the base plate 6 or by using an insulating adhesive.
The insulating film 61 is interposed between the insulating film 61 and 0.

Further, if necessary, the remaining substrate 10
The material is dissolved by etching. This treatment can also reduce the overall thermal conductivity.

As one of the devices manufactured by the above method,
The bottom of each trapezoidal thermoelectric element has a dimension of 330 μm
Suppose you want to make something that is a corner. At this time, the top surface dimension of the trapezoid is about 50 μm square.

When the space size between the first thermoelectric element 50 and the second thermoelectric element 51 is 25 μm, 23 pairs of thermocouples 70 are formed in the lateral direction in a 1 cm square substrate and 28 pairs are formed in the vertical direction. , 644 pairs are obtained as a whole. This device can obtain an output of 1.2 V by applying a temperature difference of 5 ° C. to the front and back.

[0063]

[Embodiment 2] A method for manufacturing a thermoelectric power generating element according to a second embodiment of the present invention will be described with reference to FIGS. 3 (a) to 3 (g) are cross-sectional views of a main part showing a method for manufacturing a thermoelectric power generation element according to a second embodiment of the present invention, and
[FIG. 8] is a plan view showing a metal electrode for plating formed on the back surface 12 of the substrate according to the second embodiment of the present invention.

For fabrication, a low-doped silicon wafer having a (100) orientation and a thickness of about 200 μm and having both sides polished is used as the substrate 10.

First, as shown in FIG. 3A, a gold film having a thickness of about 500 nm is formed on the front surface 11 of the substrate by a vacuum evaporation method. After that, using the photoresist as a mask film for etching, a large number of square patterns are formed on the entire surface of the gold film with a predetermined size and intervals.

Then, using this photoresist pattern, the gold film was etched with a mixed aqueous solution of iodine and potassium iodide (hereinafter referred to as potassium iodine iodide solution) as shown in FIG. A first mask 20 having the same pattern shape as is produced. After that, the photoresist is stripped and removed with a dedicated stripping solution.

Next, as shown in FIG. 3B, the same applies to the back surface 12 of the substrate. A gold film having a thickness of about 500 nm is formed by a vacuum evaporation method. This gold film is also etched and patterned into two parts as shown in FIGS. 3B and 4 by a method using a photoresist and a potassium iodine iodide solution, and the first metal film electrode 30 and the second metal film electrode 30 are formed. Metal film electrode 21
To form.

Each of the first metal film electrode 30 and the second metal film electrode 21 has a pad portion 33, and the pad portions 33 are alternately arranged.

The number and positions of the pad portions 33 are the same as the number and positions of the rectangular patterns formed by the first mask 20 described above.

After this, the entire back surface 12 of the substrate is
A Teflon-based polymer film (not shown) for protection is formed by spin coating.

The first mask 20 produced above is used as an etching mask, and as shown in FIG. 3C, the silicon of the exposed portion of the substrate 10 is removed by an etching method to form a plated hole 42.

For the etching of the substrate 10, anisotropic etching using a KOH aqueous solution or a strong alkaline aqueous solution such as a hydrazine-based aqueous solution is applied as in the first embodiment.

The substrate 10 is etched until it penetrates the substrate 10 and exposes the first metal film electrode 30 and the second metal film electrode 21 on the back surface 12 of the substrate, as shown in FIG. 3C.

Next, as shown in FIG. 3D, a plating method is used in the plating holes 42 in which the first metal film electrodes 30 on the back surface 12 of the substrate corresponding to half of the plating holes 42 are exposed. And filled with the first thermoelectric material to prepare the first thermoelectric body 50.

The first thermoelectric body 50 is an n-type semiconductor Bi.
TeSe alloy is used as the material. An acidic solution containing Bi (NO ₃ ), TeO ₂ , and SeO ₂ is used as the electrolytic solution.

The first metal film electrode 30 on the rear surface 12 of the substrate is used as a cathode, and a Pt plate is used as an anode to apply a constant voltage between both electrodes. BiTe by applying a voltage around 0.5V
The Se alloy is deposited on the first metal film electrode 30.

In this case, since the outer surface of the first metal film electrode 30 is previously covered with the polymer film, the BiTeSe alloy is deposited only in the plating hole 42, and the first thermoelectric element 50 is formed.
Can be

Further, since the silicon wafer of the substrate 10 is exposed but has a low impurity doping amount, the resistance value is much higher than that of the gold film, and leakage current does not flow.

By changing the ion concentration of Bi, Te, Se in the electrolytic solution or the applied voltage, the first thermoelectric element 50 can be produced.
The alloy composition of can be changed, and the material of the required output voltage or resistance value can be selected by setting these conditions.

Next, as shown in FIG. 3E, the remaining plating holes 42, that is, the plating holes 42 in which the second metal film electrodes 21 on the rear surface 12 of the substrate are exposed, are also formed by the plating method. The second thermoelectric body 51 is manufactured by filling the second thermoelectric material with the thermoelectric material of No. 2.

The first thermoelectric body 50 already manufactured,
And the second thermoelectric elements 51 are alternately formed, and are formed in a matrix as a whole to form a thermocouple.

The second thermoelectric element 51 is a p-type semiconductor Bi.
SbTe alloy is used as a material. Then, an acidic solution containing Bi (NO ₃ ), SbCl ₃ , and TeO ₂ is used as the electrolytic solution.

Similar to the case of manufacturing the first thermoelectric body 50, this time, the second metal film electrode 21 on the back surface 12 of the substrate is used as a cathode, and a Pt plate is used as an anode to apply a constant voltage between both electrodes. To do. BiSbT by applying a voltage around 0.5V
The e alloy is deposited on the second metal film electrode 21, and the second thermoelectric body 51 can be manufactured.

Here, the second thermoelectric body 51 is controlled by the reaction charge amount so as to deposit by the thickness of the substrate 10, and the electrical characteristics of the deposit can be changed by changing the composition of the plating bath, the electrolytic voltage and the like. You can control.

The first thermoelectric body 50 and the second thermoelectric body 51
After the plating step with and, the protective polymer film is peeled and removed using an organic solvent such as toluene.

Further, as shown in FIG. 3 (f), a gold film is newly formed on the front surface 11 and the back surface 12 of the substrate.
It is formed with a film thickness of nm by a vacuum evaporation method.

Then, using the photoresist as a mask for etching, the gold film was patterned by an etching method using a potassium iodine iodide solution.
As shown in (f), the first thermoelectric body 50 and the second thermoelectric body 50 adjacent to each other
The thermoelectric elements 51 are connected to form hot contacts 71 on the front surface 11 of the substrate and cold contacts 72 on the back surface 12 of the substrate.

Each of the hot junction 71 and the cold junction 72
Means that all thermoelectric bodies in the substrate are connected so that all thermoelectric bodies are connected in series.

Here, the first mask 20, the first metal film electrode 30, and the second metal film electrode 21 are melted before the vacuum deposition, but there is no problem if they are left.

Finally, the cold junction 7 is installed on the base 60 having a size almost the same as or slightly larger than that of the substrate 10 at the beginning of the process.
Adhere to 2.

The base 60 is made of a metal such as a copper plate, an aluminum plate, and a stainless plate, which has good heat conductivity.

In this case, the surface of the base 60 is oxidized so that the cold junction 72 is not short-circuited, or an insulator is coated on the base 60 or the cold junction 72.
Alternatively, the insulating film 61 is always interposed between the cold junction 72 and the base 60 by using an insulating adhesive or the like.

Further, if necessary, the remaining substrate 10
The material is dissolved by etching. This treatment can also reduce the overall thermal conductivity.

As one of the devices manufactured by the above method,
It is assumed that each of the trapezoidal thermoelectric elements has a bottom surface dimension of 300 μm square. At this time, the top surface dimension of the trapezoid is about 27 μm square.

When the space size between the first thermoelectric element 50 and the second thermoelectric element 51 is 10 μm, 16 pairs of thermocouples 70 are formed in the lateral direction in a 1 cm square substrate and 32 pairs are formed in the vertical direction. , 512 pairs are obtained as a whole. This device can obtain an output of 1 V by applying a temperature difference of 5 ° C. to the front and back.

As described above, in the first and second embodiments, the (100) -oriented silicon wafer is used as the material of the substrate 10, but a (110) -oriented silicon wafer can also be used.

It is also possible to use photosensitive ceramics as the material of the substrate 10 instead of the silicon wafer.

Further, titanium (Ti), nickel (Ni), aluminum (Al), copper (Cu), iron (Fe) or the like can be used as the electrode material or the mask material instead of the gold film. If used only as a mask for etching, a SiO ₂ film or a Si ₃ N ₄ film can also be used.

Further, not only the vacuum vapor deposition method but also the sputtering method, the ion plating method, the CVD method and the like can be applied to the method of forming these coatings. Furthermore, as the thermoelectric body, any known material that can be plated can be used.

[0100]

As is apparent from the above description, according to the present invention, a new method of combining fine processing of a substrate by photolithography and etching technology and plating of a thermoelectric material to form a fine area in a narrow area can be achieved. It is possible to form a large number of different thermocouples.

This manufacturing method is effective for manufacturing a minute thermoelectric power generation element having a sufficient output, and the manufactured thermoelectric power generation element has a higher integration density and power density than ever before. By miniaturizing the thermoelectric power generation element by this method, there is a possibility that the temperature difference power generation can be used for a portable electronic device such as a wrist watch which has not been practically available in the past. Further, this manufacturing method is expected to be applied not only to the temperature difference power generation but also as a new manufacturing method for a small thermoelectric cooling device or a thermoelectric heating device.

[Brief description of drawings]

FIG. 1 is a cross-sectional view of essential parts showing a method for manufacturing a thermoelectric power generation element according to a first embodiment of the present invention.

FIG. 2 is a plan view showing a thermoelectric power generation element manufactured by the method for manufacturing a thermoelectric power generation element according to the first embodiment of the present invention.

FIG. 3 is a cross-sectional view of a main part showing a method for manufacturing a thermoelectric power generation element according to a second embodiment of the present invention.

FIG. 4 is a plan view showing a metal film electrode for plating formed on the back surface of a substrate, which is manufactured by a method for manufacturing a thermoelectric power generation element according to a second embodiment of the present invention.

FIG. 5 is a perspective view showing a structure of a thermoelectric power generation element.

[Explanation of symbols]

 10 substrate 11 substrate front surface 12 substrate back surface 20 first mask 21 second metal film electrode 30 first metal film electrode 31 second mask 32 third metal film electrode 40 first hole 41 second Hole 42 Plating hole 50 First thermoelectric body 51 Second thermoelectric body 60 Base 61 Insulating film 70 Thermocouple 71 Hot junction 72 Cold junction

Claims (2)

[Claims] 1. A step of forming a first hole penetrating from the front surface of the substrate to the back surface of the substrate by etching, and filling the first hole by using a first metal film electrode formed on the back surface of the substrate. The step of forming the first thermoelectric body made of the first thermoelectric material by the plating method, and the substrate is arranged from the back surface of the substrate so as to be arranged alternately with the first holes and arranged in a matrix with the first holes. A step of forming a second hole penetrating to the front surface by etching and a second step of filling the second hole by using the second metal film electrode formed on the front surface of the substrate.
Forming a second thermoelectric body made of a thermoelectric material by a plating method, and patterning the second metal film electrode to connect the first thermoelectric body and the second thermoelectric body which are adjacent to each other to warm them. After forming the contacts and making a number of thermocouples, patterning the third metal film electrode newly formed on the backside of the substrate to form cold junctions and connecting all the thermocouples in series, And a step of adhering a base made of a metal plate so as to come into contact with the cold junctions of all thermocouples. 2. A first substrate, each of which is alternately arranged on the back surface of the substrate.
Of forming the metal film electrode and the second metal film electrode, forming a plating hole penetrating from the front surface of the substrate to the back surface of the substrate by etching, and forming a plating hole using the first metal film electrode. A step of forming a first thermoelectric body made of a first thermoelectric material by a plating method so as to fill half of the plating holes therein, and a second metal film electrode is used to alternately line up the first thermoelectric body and the substrate. A step of forming a second thermoelectric body made of a second thermoelectric material by a plating method so as to fill the remaining half of the plating holes so as to be arranged in a matrix with the first thermoelectric body as a whole; Patterning the metal film formed on the front surface and the back surface of the substrate and connecting the adjacent first and second thermoelectric bodies to form a hot junction on the front surface of the substrate and a cold junction on the back surface of the substrate. By connecting all thermocouples in series The method of the thermoelectric power generation element rear surface of the substrate, characterized in that a step of pasting into contact with the cold junction of all the thermocouples base made of a metal plate.