JP4013918B2 - Thermoelectric module substrate, manufacturing method thereof, and thermoelectric module - Google Patents

Description

  The present invention relates to a substrate for a thermoelectric module that converts thermal energy into electric power, a method for manufacturing the same, and a thermoelectric module, and more particularly to a substrate for a thermoelectric module that is resistant to thermal cycling, a method for manufacturing the same, and a thermoelectric module.

  Conventionally, as a thermoelectric module, what is indicated by patent documents 1 is known. FIG. 17 is a cross-sectional view showing a conventional thermoelectric module.

  As shown in FIG. 17, this conventional thermoelectric module 100 has a metal plate 101 coated with a ceramic layer 102, a board in which screw holes are drilled at necessary positions, and is sandwiched by the board to correspond to the screw holes. And the thermoelectric element 104 formed at both ends thereof. A pair of the substrates is used, and the thermoelectric element 104 is fixed by an insulating fixing screw 106 through the metal segment 103.

JP-A-10-144970

  However, in the conventional thermoelectric module 100 disclosed in Patent Document 1, the thermal expansion coefficient or the thermal shock is applied because the metal plate 101 formed of Cu or Al or the like has a different thermal expansion coefficient. Further, there is a problem that peeling occurs at the interface between the metal plate 101 and the ceramic layer 102 due to thermal stress.

  In addition, the conventional thermoelectric module 100 disclosed in Patent Document 1 has a problem in that the thermoelectric element 104 must be fixed with an insulating fixing screw 106, which is difficult to assemble.

  The present invention has been made in view of such a problem, and has a metal substrate formed with irregularities, a stress relaxation film is formed between the metal substrate and the insulation film, and further, the insulation film and the stress relaxation film. The substrate for a thermoelectric module that can prevent the separation at the interface between the metal substrate and the insulating film even when a thermal cycle or thermal shock is applied, a method for manufacturing the thermoelectric module, and the thermoelectric module The purpose is to provide.

A substrate for a thermoelectric module according to the first invention of the present application includes a metal substrate having an uneven surface, an insulating film formed on the metal substrate and impregnated with an organic or inorganic insulating material, and the insulating film. And an electrode formed on the substrate.

A thermoelectric module substrate according to a second invention of the present application is impregnated with a metal substrate, a stress relaxation film formed on the metal substrate, and an organic or inorganic insulating material formed on the stress relaxation film. And an electrode formed on the insulating film.

  These thermoelectric module substrates may be partitioned by grooves that reach the metal substrate for each of one or a plurality of electrode formation regions.

The thermoelectric module substrate according to the third invention of the present application includes a metal substrate that is partitioned by one or a plurality of electrode forming regions and an organic or inorganic insulating material formed on the metal substrate. It has an impregnated insulating film and an electrode formed on the insulating film.

A method for manufacturing a substrate for a thermoelectric module according to a fourth invention of the present application includes a step of forming irregularities on a surface of a metal substrate, a step of forming an insulating film on the surface of the metal substrate, and an organic or inorganic type on the insulating film. A step of impregnating with an insulating material , and a step of forming an electrode on the insulating film.

A method for manufacturing a substrate for a thermoelectric module according to a fifth invention of the present application includes a step of masking the surface of a metal substrate to form irregularities for each of one or more electrode formation scheduled areas, and the one or more electrode formation scheduled areas The method includes a step of forming an insulating film every time, a step of impregnating the insulating film with an organic or inorganic insulating material , and a step of forming an electrode on the insulating film.

  In these methods for manufacturing a thermoelectric module substrate, the electrodes can be formed by thermal spraying. The insulating film may be formed by thermal spraying.

  A thermoelectric module according to a sixth invention of the present application is characterized in that a pair of the aforementioned thermoelectric module substrates is provided, and a thermoelectric element connected to the electrode is provided between the thermoelectric module substrates.

  In the present invention, by forming irregularities on the surface of the metal substrate and increasing the adhesion with the insulating film formed on the surface, the metal is applied when thermal stress such as thermal cycle or thermal shock acts. Separation of the interface between the substrate and the insulating film can be prevented.

  Further, in the present invention, by forming a stress relaxation film between the metal substrate and the insulating film, when a thermal stress such as a thermal cycle or thermal shock acts, the stress relaxation film relaxes the thermal stress. Separation of the interface between the metal substrate and the insulating film can be prevented.

  According to the present invention, by forming unevenness on the surface of the metal substrate, it is possible to increase the adhesion with the insulating film formed on this surface, so that when thermal stress such as thermal cycle or thermal shock acts In this case, peeling of the interface between the metal substrate and the insulating film can be prevented.

  Further, in the present invention, by forming a stress relaxation film between the metal substrate and the insulating film, when a thermal stress such as a thermal cycle or thermal shock acts, the stress relaxation film relaxes the thermal stress. Separation of the interface between the metal substrate and the insulating film can be prevented. Furthermore, the heat cycle resistance can be improved by dividing the insulating film into one or a plurality of electrode formation regions of the metal substrate.

  Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings. FIG. 1 is a cross-sectional view showing a thermoelectric module substrate according to a first embodiment of the present invention.

  In the thermoelectric module substrate 1 according to the first embodiment of the present invention, an insulating film 4 is formed on a metal substrate 2 having an uneven surface 3. Furthermore, an electrode 6 is formed on the insulating film 4.

  As described above, by forming irregularities on the surface 3 of the metal substrate 2, the surface area can be increased, the adhesion between the metal substrate 2 and the insulating film 4 can be increased, and the heat cycle resistance can be improved.

  Next, a method for manufacturing a thermoelectric module according to the first embodiment of the present invention will be described with reference to FIGS. 2A and 2B are cross-sectional views showing a method of manufacturing a thermoelectric module substrate according to the first embodiment of the present invention in the order of steps. First, as shown in FIG. 2A, unevenness is formed on the surface 3 of the metal substrate 2 by, for example, sandblasting or chemical etching.

Next, as shown in FIG. 2B, for example, an Al ₂ O ₃ film is formed as the insulating film 4 on the surface 3 of the metal substrate 2 on which the unevenness is formed.

  Next, using a mask, a Cu sprayed film is formed by spraying, for example, as the electrode 6 in the region where the electrode 6 is to be formed on the insulating film 4. And as shown in FIG. 1, the board | substrate 1 for thermoelectric modules is formed.

  As described above, by forming irregularities on the surface 3 of the metal substrate 2, it is possible to form the insulating film 4 with an increased surface area and high adhesion.

  Next, a second embodiment of the present invention will be specifically described with reference to FIG. The same components as those in the first embodiment shown in FIGS. 1 and 2 are denoted by the same reference numerals, and detailed description thereof is omitted. FIG. 3 is a sectional view of a thermoelectric module substrate according to a second embodiment of the present invention.

  This embodiment is different from the first embodiment in that the insulating film 4 is formed only in the electrode 6 formation region, and the other configuration is the same as that of the first embodiment.

  As described above, by forming the insulating film 4 only in the electrode 6 formation region, the contact area between the insulating film 4 and the metal substrate 2 is reduced, and when thermal stress acts, the entire thermoelectric module substrate 1 is formed. It is possible to reduce the thermal stress that is received.

  Next, the manufacturing method of the thermoelectric module of a present Example is demonstrated. First, unevenness is formed over the entire surface 3 of the metal substrate 2 by, for example, sandblasting or chemical etching.

Next, a mask is applied to the surface 3 of the region where the electrode 6 is to be formed where irregularities are formed, and an Al ₂ O ₃ film, for example, is formed as an insulating film 4 on the surface 3.

  Next, a mask is formed on the insulating film 4 and a Cu sprayed film is formed as the electrode 6 by, for example, spraying. Then, as shown in FIG. 3, the thermoelectric module substrate 1 is formed. This reduces material costs.

  In this embodiment, the insulating film 4 is formed only in the electrode 6 formation region. However, the present invention is not particularly limited to this, and covers a region including a plurality of electrode 6 formation regions. The insulating film 4 can be formed.

  Next, a third embodiment of the present invention will be specifically described with reference to FIG. The same components as those in the first embodiment shown in FIGS. 1 and 2 are denoted by the same reference numerals, and detailed description thereof is omitted. FIG. 4 is a cross-sectional view of a thermoelectric module substrate according to a third embodiment of the present invention.

  In this embodiment, as compared with the first embodiment, unevenness is formed on the surface 3 of the metal substrate 2 only in the electrode 6 formation region, and the other surfaces 3 of the metal substrate 2 other than that are flattened. This is different from the first embodiment in that an insulating film 4 is formed on the surface 3 of the metal substrate 2 on which the irregularities are formed.

  As described above, when the unevenness is formed on the surface 3 of the metal substrate 2 only in the electrode 6 formation region and the surface 3 of the other metal substrate 2 is planarized, Since unnecessary residual stress is not generated in 2, deformation of the metal substrate 2 can be suppressed. In addition, since the contact area between the insulating film 4 and the metal substrate 2 is reduced and thermal stress acts, the thermal stress received by the thermoelectric module substrate 1 is reduced, so that the heat cycle resistance is improved.

  Next, the manufacturing method of the thermoelectric module of a present Example is demonstrated. First, the metal substrate 2 is masked, and unevenness is formed only on the surface 3 of the metal substrate 2 in the region where the electrode 6 is to be formed, for example, by sandblasting or chemical etching.

Next, the surface 3 is masked, and an Al ₂ O ₃ film, for example, is formed as the insulating film 4 on the surface 3 of the region where the electrode 6 is to be formed where the irregularities are formed.

  Next, using a mask, a Cu sprayed film is formed on the insulating film 4 as an electrode 6 by thermal spraying, for example. Then, as shown in FIG. 4, the thermoelectric module substrate 1 is formed. Since the insulating film 4 is formed only in the electrode 6 formation region, the metal substrate 2 and the insulating film 4 are formed more than the case where the insulating film 4 is formed over the entire surface 3 of the metal substrate 2. The stress generated at the interface is reduced and the heat cycle resistance is increased. In addition, material costs are reduced.

  In the present embodiment, the unevenness is formed on the surface 3 of the metal substrate 2 only in the electrode 6 formation region, but the present invention is not particularly limited to this, and the surface 3 of the metal substrate 2 is not limited to this. It can also be set as a flat structure.

  Next, a fourth embodiment of the present invention will be specifically described with reference to FIG. The same components as those in the first embodiment shown in FIGS. 1 and 2 are denoted by the same reference numerals, and detailed description thereof is omitted. FIG. 5 is a sectional view of a thermoelectric module substrate according to a fourth embodiment of the present invention.

  In this embodiment, as compared with the first embodiment, unevenness is formed on the surface 3 of the metal substrate 2 only in the electrode 6 formation region, and the other surface 3 of the metal substrate 2 reaches the metal substrate 2. A groove 7 is formed and partitioned. This is different from the first embodiment in that an insulating film 4 is formed on the surface 3 of the metal substrate 2 on which the irregularities are formed.

  As described above, by forming the groove 7 reaching the metal substrate 2 for each electrode 6 formation region, the residual stress generated in the metal substrate 2 is further reduced, and the deformation of the metal substrate 2 is suppressed. In addition, when heat is applied to the metal substrate 2, heat is released by the grooves 7 and the thermal stress received by the thermoelectric module substrate 1 is reduced, so that heat cycle resistance is improved.

  Next, the manufacturing method of the thermoelectric module of a present Example is demonstrated. First, the metal substrate 2 is masked, and irregularities are formed only on the surface 3 of the metal substrate 2 in the region where the electrodes 6 are to be formed, for example, by sandblasting or chemical etching. And the groove | channel 7 is formed by cutting in the metal substrate 2 except the unevenness | corrugation formed.

Next, using a mask, for example, an Al ₂ O ₃ film is formed as the insulating film 4 on the surface 3 of the region where the electrode 6 is to be formed.

  Next, using a mask, a Cu sprayed film is formed on the insulating film 4 as an electrode 6 by thermal spraying, for example. Then, as shown in FIG. 5, the thermoelectric module substrate 1 is formed. This reduces material costs.

  In this embodiment, the grooves 7 are formed by cutting. However, the present invention is not particularly limited to this, and the metal substrate 2 on which the grooves 7 are formed in advance can also be used.

  Further, in this embodiment, irregularities are formed on the surface 3 of the metal substrate 2, and further, grooves 7 reaching the metal substrate 2 are formed on the surface 3 of the other metal substrate 2 for each electrode 6 formation region. However, the present invention is not particularly limited to this, and the groove 7 may be formed over a plurality of electrode 6 formation regions. Further, the surface 3 of the metal substrate 2 can be made flat.

  Next, a fifth embodiment of the present invention will be specifically described with reference to FIGS. The same components as those in the first embodiment shown in FIGS. 1 and 2 are denoted by the same reference numerals, and detailed description thereof is omitted. FIG. 6 is a cross-sectional view of a thermoelectric module substrate according to a fifth embodiment of the present invention. 7A to 7C are cross-sectional views showing a method of manufacturing a thermoelectric module substrate according to a fifth embodiment of the present invention in the order of steps.

  The present embodiment is different from the first embodiment in that a stress relaxation film 5 is formed between the metal substrate 2 and the insulating film 4, and the rest is the same as the first embodiment. is there.

  As described above, by forming the stress relaxation film 5 between the metal substrate 2 and the insulating film 4, the thermal stress generated between the insulating film 4 and the electrode 6 and the metal substrate 2 is relaxed, and the metal substrate 2. Therefore, the heat cycle resistance is further improved.

  Next, the manufacturing method of the thermoelectric module of a present Example is demonstrated. First, as shown in FIG. 7A, irregularities are formed on the surface 3 of the metal substrate 2 by, for example, sandblasting or chemical etching.

Next, as shown in FIG. 7B, for example, a Ni ₈₀ Cr ₂₀ film is formed as the stress relaxation film 5 on the surface 3 of the metal substrate 2 on which the unevenness is formed.

Next, as shown in FIG. 7C, for example, an Al ₂ O ₃ film is formed as the insulating film 4 on the stress relaxation film 5.

  Next, using a mask, a Cu sprayed film is formed by spraying, for example, as the electrode 6 in the region where the electrode 6 is to be formed on the insulating film 4. Then, as shown in FIG. 6, the thermoelectric module substrate 1 is formed.

  As described above, since the metal substrate 2 and the insulating film 4 are formed via the stress relaxation film 5, the thermal stress between the metal substrate 2 and the insulating film 4 can be relaxed. Can be formed.

  In this embodiment, the unevenness is formed only on the surface 3 of the metal substrate 2, but the unevenness is also formed on the surface of the stress relaxation film 5 to increase the surface area and further improve the adhesion with the insulating film 4. Can do.

  Next, a sixth embodiment of the present invention will be specifically described with reference to FIG. The same components as those in the fifth embodiment shown in FIGS. 6 and 7 are denoted by the same reference numerals, and detailed description thereof is omitted. FIG. 8 is a cross-sectional view of a thermoelectric module substrate according to a sixth embodiment of the present invention.

  The present embodiment is different from the fifth embodiment in that the insulating film 4 and the stress relaxation film 5 are formed only in the electrode 6 formation region, and the other configuration is the same as that of the fifth embodiment. is there.

  As described above, since the insulating film 4 and the stress relaxation film 5 are formed only in the electrode 6 formation region and the thermal stress is applied, the formation area of the insulating film 4 is small. The thermal stress received by the whole 1 is reduced, and the thermal stress can be relaxed by the stress relaxation film 5.

  Next, the manufacturing method of the thermoelectric module of a present Example is demonstrated. First, unevenness is formed over the entire surface 3 of the metal substrate 2 by, for example, sandblasting or chemical etching.

Next, using a mask, the stress relaxation film 5 is formed on the surface 3 on which the unevenness of the region where the electrode 6 is to be formed is formed. On the stress relaxation film 5, for example, an Al ₂ O ₃ film is formed as the insulating film 4.

  Next, using a mask, a Cu sprayed film is formed by spraying, for example, as the electrode 6 in the region where the electrode 6 is to be formed on the insulating film 4. Then, as shown in FIG. 8, the thermoelectric module substrate 1 is formed. This reduces material costs.

  In this embodiment, the unevenness is formed only on the surface 3 of the metal substrate 2, but the unevenness is also formed on the surface 3 of the stress relaxation film 5 to increase the surface area and further improve the adhesion with the insulating film 4. be able to.

  In the present embodiment, the insulating film 4 and the stress relaxation film 5 are formed only in the electrode 6 formation region. However, the present invention is not particularly limited to this, and a plurality of electrodes 6 are formed. The insulating film 4 and the stress relaxation film 5 can be formed over the region including the region.

  Next, a seventh embodiment of the present invention will be specifically described with reference to FIG. The same components as those in the fifth embodiment shown in FIGS. 6 and 7 are denoted by the same reference numerals, and detailed description thereof is omitted. FIG. 9 is a sectional view of a thermoelectric module substrate according to a seventh embodiment of the present invention.

  In the present embodiment, as compared with the fifth embodiment, unevenness is formed on the surface 3 of the metal substrate 2 only in the electrode 6 formation region, and the other surfaces 3 of the metal substrate 2 other than that are flattened. This embodiment is the same as the fifth embodiment except that a stress relaxation film 5 is formed on the surface 3 of the metal substrate 2 on which the irregularities are formed, and an insulating film 4 is formed thereon.

  As described above, unevenness is formed on the surface 3 of the metal substrate 2 only in the electrode 6 formation region, and unevenness is formed on the surface 3 of the metal substrate 2 by flattening the surface 3 of the other metal substrate 2. Since there are few areas, the residual stress which arises in the metal substrate 2 decreases, and the deformation | transformation of the metal substrate 2 can be suppressed. Furthermore, when the thermal stress is applied, since the formation area of the insulating film 4 is small, the thermal stress applied to the entire thermoelectric module substrate 1 is reduced, and the thermal stress is reduced by the stress relaxation film 5. Therefore, heat cycle resistance is improved.

  Next, the manufacturing method of the thermoelectric module of a present Example is demonstrated. First, the surface 3 of the metal substrate 2 is masked, and unevenness is formed only in the electrode 6 formation region by, for example, sandblasting or chemical etching.

Next, using a mask, the stress relaxation film 5 is formed on the surface 3 of the region where the electrode 6 is to be formed where the irregularities are formed. On the stress relaxation film 5, for example, an Al ₂ O ₃ film is formed as the insulating film 4.

  Next, using a mask, a Cu sprayed film is formed on the insulating film 4 as an electrode 6 by thermal spraying, for example. Then, as shown in FIG. 9, the thermoelectric module substrate 1 is formed. This reduces material costs.

  In this embodiment, the unevenness is formed only on the surface 3 of the metal substrate 2, but the unevenness can also be formed on the surface of the stress relaxation film 5 to improve the adhesion with the insulating film 4.

  Next, an eighth embodiment of the present invention will be specifically described with reference to FIG. The same components as those in the fifth embodiment shown in FIGS. 6 and 7 are denoted by the same reference numerals, and detailed description thereof is omitted. FIG. 10 is a cross-sectional view of a thermoelectric module substrate according to an eighth embodiment of the present invention.

  In this embodiment, as compared with the fifth embodiment, unevenness is formed on the surface 3 of the metal substrate 2 only in the electrode 6 formation region, and the surface 3 of the other metal substrate 2 reaches the metal substrate 2. A groove 7 is formed and partitioned. This is different from the fifth embodiment except that a stress relaxation film 5 is formed on the surface 3 of the metal substrate 2 on which the irregularities are formed, and an insulating film 4 is formed thereon. .

  As described above, irregularities are formed on the surface 3 of the metal substrate 2 for each electrode 6 formation region, and a groove 7 reaching the metal substrate 2 is formed on the surface 3 of the other metal substrate 2, so that the metal When unevenness is formed on the surface 3 of the substrate 2, the residual stress generated in the metal substrate 2 is further reduced, so that deformation of the metal substrate 2 can be suppressed. In addition, when heat is applied to the metal substrate 2, heat is released by the grooves 7 to reduce the thermal stress received by the thermoelectric module substrate 1, and the stress relaxation film 5 can reduce the thermal stress. it can.

  Next, the manufacturing method of the thermoelectric module of a present Example is demonstrated. First, a mask is formed on the surface 3 of the metal substrate 2 and unevenness is formed only in the electrode 6 formation region by, for example, sandblasting or chemical etching. Except for the region where the irregularities are formed, the grooves 7 are formed.

Next, using a mask, for example, Al ₂ O ₃ is formed as the insulating film 4 on the stress relaxation film 5 on the surface 3 of the region where the electrode 6 is to be formed.

  Next, using a mask, a Cu sprayed film is formed on the insulating film 4 as an electrode 6 by thermal spraying, for example. Then, as shown in FIG. 10, the thermoelectric module substrate 1 is formed. This reduces material costs.

  In this embodiment, the unevenness is formed only on the surface 3 of the metal substrate 2, but the unevenness is also formed on the surface 3 of the stress relaxation film 5 to enlarge the surface area and further improve the adhesion with the insulating film 4. be able to.

In any of the above-described embodiments, the electrode 6 is formed by thermal spraying. However, the present invention is not particularly limited to this, and the electrode 6 can be formed by firing a metal paste. FIG. 11 is a cross-sectional view showing electrode formation by firing according to the thermoelectric module substrate of the present invention. As shown in FIG. 11, the electrode 6 can be formed by depositing and baking, for example, Cu or Ag paste in the region where the electrode 6 is to be formed. At this time, in the case of Cu paste, it is desirable that the insulating film 4 is Al ₂ O ₃ containing SiO ₂ that helps adhesion with the paste.

  Moreover, the electrode 6 can also be formed by plating. FIG. 12 is a sectional view showing electrode formation by plating according to the thermoelectric module substrate of the present invention. As shown in FIG. 12, a region other than the region where the electrode 6 is to be formed is covered on the insulating film 4 with a mask 8. Then, for example, a Pd film is formed on the insulating film 4 in a region where the electrode 6 is to be formed, and the electrode 6 can be formed by sequentially depositing Ni plating and Cu plating.

  Furthermore, the electrode 6 can be formed by adhesion. FIG. 13 is a cross-sectional view showing the formation of the electrode 6 by bonding according to the thermoelectric module substrate of the present invention. As shown in FIG. 13, the electrode 6 can be formed by sticking a Cu plate to the region where the electrode 6 is to be formed, for example, with an adhesive 9 made of an epoxy resin.

  In any of the above-described embodiments, the insulating film 4 is formed by a thermal spraying method. However, the present invention is not particularly limited to this, and a sputtering method, a CVD method, a vacuum deposition method or a sol is not limited thereto. -It can be formed by a gel method or the like.

Further, in any of the above-described embodiments, the metal substrate 2 can selectively use any of Al, Al alloy, Cu, or Cu alloy. Further, the insulating film 4 is not limited to the Al ₂ O ₃ film, and is not limited to AlN, TiO ₂ , CrO ₃ , CaO, MgO, SiO ₂ , Cr ₃ C ₂ , SiC, TiC, Si ₃ N ₄ , WC, Any of Y ₂ O ₃ , NiO and ZrO ₂ can be used selectively. The insulating film 4 may be a mixed film or a multilayer film.

Furthermore, in any of the above-described embodiments, the insulating properties can be improved by impregnating the insulating film 4 with an organic or inorganic material such as epoxy resin, silicone, or SiO ₂ .

  Next, a ninth embodiment of the present invention will be specifically described with reference to FIG. FIG. 14 is a sectional view of a thermoelectric module substrate according to a ninth embodiment of the present invention.

  In the present embodiment, for example, Al or an Al alloy is used as the metal substrate 2. An alumite film 10 is formed as an insulating film 4 on the metal substrate 2. An electrode 6 is formed on the alumite film 10.

  Thereby, the adhesive force between the metal substrate 2 and the insulating film 4 is improved.

  Next, the manufacturing method of the thermoelectric module of a present Example is demonstrated. An alumite film 10 is formed on the metal substrate 2. Next, using a mask, the electrode 6 is formed on the alumite film 10 so as not to break the alumite film 10.

  Thereby, since the thermal spraying method is used only when the electrode 6 is formed, the cost can be reduced.

  In any of the above-described embodiments, the insulating film 5 or the electrode 6 is shaped by a thermal spraying method, but this thermal spraying method often applies a plasma spraying method. However, the present invention is not particularly limited to this, and arc spraying method, line explosion spraying method, electrothermal explosion spraying method, laser spraying method, low-pressure plasma spraying method, laser composite spraying method, flame spraying method or explosion spraying. Thermal spraying methods such as the method can be used as appropriate. Further, when the insulating film 4 is formed separately for each electrode 6, the insulating reliability is improved by forming the insulating film 4 larger than the size of the electrode 6.

  Next, a tenth embodiment of the present invention will be specifically described with reference to FIG. The same components as those in the first embodiment shown in FIGS. 1 and 2 are denoted by the same reference numerals, and detailed description thereof is omitted. FIG. 15 is a perspective view of a thermoelectric module according to a tenth embodiment of the present invention.

  In the thermoelectric module according to the tenth embodiment of the present invention, an insulating film 4 is formed on a metal substrate 2 having an uneven surface 3 and an electrode is formed on the insulating film 4. And a plurality of thermoelectric elements 11 sandwiched between the pair of electric module substrates 1. Each of the thermoelectric elements 11 is in contact with the electrode 6 for each element unit A of the thermoelectric element 11.

  This eliminates the need for fixing with screws or the like and facilitates assembly. In addition, since the thermoelectric module substrate 1 is strong against thermal cycles, the thermoelectric module has excellent heat cycle characteristics.

  In the present embodiment, the thermoelectric module substrate is not particularly limited to this. For example, in the region other than the electrode 6 formation region, the groove 7 divided for each electrode 6 or for each of the plurality of electrodes 6 is formed. It can also be configured. In addition, the insulating film 4, the stress relaxation film 5, and the groove 7 are not limited to the structure formed for each electrode 6, but may be formed over a plurality of electrodes 6. Furthermore, the thermoelectric module substrate 1 of any of the above embodiments may be used.

  Hereinafter, the effects of the thermoelectric module substrate according to the present invention will be specifically described in comparison with comparative examples that are out of the scope of the present invention. FIG. 16 is a cross-sectional view showing a thermoelectric module according to an embodiment of the present invention.

First, using the thermoelectric module substrate 1 shown in Tables 1 to 6, a plurality of thermoelectric elements 11 are sandwiched by a pair of thermoelectric module substrates 1 as shown in FIG. A thermoelectric module was prepared so as to be in contact with the electrode 6 for each element unit A of the element 11. The substrate was 40 mm long, 40 mm wide, and 1 mm thick. In addition, Al, Al alloy (SOS2), anodized Al and Cu are used as the substrate material, and the size of the thermoelectric element is 1.4 mm in length, 1.4 mm in width, and 1.6 mm in height. 127 pairs of the thermoelectric elements were used. Further, as the sealing material, epoxy resin, silicone or SiO ₂ was used.

  Next, a heat cycle test was performed using the produced thermoelectric module. In the heat cycle test A, the temperature was kept at −40 ° C. for 15 minutes, then the temperature was raised to 85 ° C. and kept for 15 minutes, and this was repeated 20 cycles. In the heat cycle test B, the temperature was kept at −40 ° C. for 15 minutes, then the temperature was raised to 85 ° C. and kept for 15 minutes, and this was repeated 40 cycles.

  In the evaluation of the heat cycle tests A and B, the interface between the metal substrate 2 and the insulating substrate was observed after the completion of the test, and “O” indicates that there is no crack and “X” indicates that there is a crack. Moreover, it was set as x also when conduction in a thermoelectric module was lost. These evaluation results are shown in Tables 7 to 9.

  As shown in Tables 7 to 9, the examples within the scope of the present invention were able to obtain results equal to or better than the conventional comparative examples in the heat cycle test. On the other hand, the comparative example which is out of the scope of the present invention could not obtain good results.

  In Examples Nos. 1 and 2, the electrodes were formed by thermal spraying or plating instead of screwing, and the heat cycle resistance equivalent to screwing could be obtained even when the electrodes were integrated with the metal substrate. .

  In Examples Nos. 3 to 6, the heat cycle resistance was improved by forming a NiCr alloy as a stress relaxation film between the metal substrate and the insulating film. This is because thermal stress resulting from the difference in coefficient of thermal expansion between the metal substrate and the insulating film is relieved by this stress relaxation film, and the adhesive force with the metal substrate itself is higher than that of the insulating film.

  Example No. 7 is divided for each thermoelectric element region up to the unevenness forming region of the underlying metal substrate, the insulating film, and the NiCr film as the stress relaxation film. It is possible to prevent the metal substrate from warping due to the residual stress generated when the unevenness of the underlying metal surface is formed. In addition, the thermal stress generated can be reduced as compared with the case where an insulating film is formed on the entire surface of the metal substrate.

  In Example No. 8, an alumite film is used as an insulating film, and an electrode is formed by a thermal spraying method so as not to destroy the alumite film. Since the thermal spraying is performed only once, the cost can be reduced.

Examples Nos. 9 to 23 use substrates in which various ceramics are thermally sprayed onto a metal substrate. The insulating film is typically an Al ₂ O ₃ film, but may be other types of ceramics or composite ceramics composed of a plurality of ceramics.

In Examples Nos. 24 and 25, since the sprayed film is usually porous, fine holes are formed. In order to improve the insulating properties, filling with an organic or inorganic material such as epoxy resin, silicone or SiO ₂ and sealing treatment can provide excellent insulation and high reliability.

  In Comparative Examples No. 1 and 2, since the thermoelectric module was fixed by screwing, peeling occurred at the interface between the metal substrate and the insulating film.

It is sectional drawing which shows the board | substrate for thermoelectric modules which concerns on 1st Example of this invention. (A) And (b) is sectional drawing which shows the manufacturing method of the board | substrate for thermoelectric modules which concerns on 1st Example of this invention in process order. It is sectional drawing of the board | substrate for thermoelectric modules which concerns on 2nd Example of this invention. It is sectional drawing of the board | substrate for thermoelectric modules which concerns on 3rd Example of this invention. It is sectional drawing of the board | substrate for thermoelectric modules which concerns on 4th Example of this invention. It is sectional drawing of the board | substrate for thermoelectric modules which concerns on 5th Example of this invention. (A) thru | or (c) is sectional drawing which shows the manufacturing method of the board | substrate for thermoelectric modules which concerns on 5th Example of this invention in order of a process. It is sectional drawing of the board | substrate for thermoelectric modules which concerns on 6th Example of this invention. It is sectional drawing of the board | substrate for thermoelectric modules which concerns on 7th Example of this invention. It is sectional drawing of the board | substrate for thermoelectric modules which concerns on 8th Example of this invention. It is sectional drawing which shows electrode formation by baking which concerns on the board | substrate for thermoelectric modules of this invention. It is sectional drawing which shows the electrode formation by the plating which concerns on the board | substrate for thermoelectric modules of this invention. It is sectional drawing which shows the electrode 6 formation by adhesion | attachment which concerns on the board | substrate for thermoelectric modules of this invention. It is sectional drawing of the board | substrate for thermoelectric modules which concerns on 9th Example of this invention. It is a perspective view of the thermoelectric module which concerns on 10th Example of this invention. It is sectional drawing which shows the thermoelectric module which concerns on the Example of this invention. It is sectional drawing which shows the conventional thermoelectric module.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1; Thermoelectric module substrate, 2, 101; Metal substrate, 3; Surface, 4: Insulating film, 5; Stress relaxation film, 6, 105; Electrode, 7: Flat part, 8; Mask, 9; Alumite film, 11, 104; thermoelectric element, 100; thermoelectric module, 102; ceramic layer, 103, metal segment, 106; fixing screw, A; element unit

Claims (9)

A metal substrate having an uneven surface; an insulating film formed on the metal substrate and impregnated with an organic or inorganic insulating material; and an electrode formed on the insulating film. A substrate for a thermoelectric module. A metal substrate, a stress relaxation film formed on the metal substrate, an insulating film formed on the stress relaxation film and impregnated with an organic or inorganic insulating material, and formed on the insulating film And a thermoelectric module substrate. 3. The thermoelectric module substrate according to claim 1, wherein the thermoelectric module substrate is divided by a groove that reaches the metal substrate for each of one or a plurality of electrode formation regions. A metal substrate having grooves formed in one or a plurality of electrode formation regions, an insulating film formed on the metal substrate and impregnated with an organic or inorganic insulating material, and the insulating film A thermoelectric module substrate comprising: an electrode formed on the substrate; A step of forming irregularities on the surface of the metal substrate; a step of forming an insulating film on the surface of the metal substrate; a step of impregnating the insulating film with an organic or inorganic insulating material ; and A method of manufacturing a substrate for a thermoelectric module, comprising: forming an electrode. Masking the surface of the metal substrate to form irregularities for each of the one or more electrode formation scheduled areas, forming an insulating film for each of the one or more electrode formation scheduled areas, and forming an organic layer on the insulating film A method for manufacturing a substrate for a thermoelectric module, comprising: impregnating a base or inorganic insulating material ; and forming an electrode on the insulating film. The said electrode is formed by thermal spraying, The manufacturing method of the board | substrate for thermoelectric modules of Claim 5 or 6 characterized by the above-mentioned. The method for manufacturing a substrate for a thermoelectric module according to any one of claims 5 to 7, wherein the insulating film is formed by thermal spraying. Claims 1 to provided a pair of thermoelectric module substrate according to any one of 4, while the substrate the thermoelectric module, thermoelectric, characterized in that a connection thermoelectric element to the electrode module.

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