JP2005101473A - Thermoelectric module and its manufacturing method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a highly reliable thermoelectric module in which the joining strength of a lead wire is high. <P>SOLUTION: In joining of the lead wire 3 and the end part 4a of a wiring conductor 4, by providing a gap 6a between the lead wire 3 and solder 6 and a thermoelectric element 5, degradation by the reaction of the lead wire 3 and the solder 6 and the thermoelectric element 5 is prevented. Especially, by joining the solder 6 by a laser and controlling the cooling time, the above effect is improved further. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to a thermoelectric module that can be suitably used for cooling a heating element such as a semiconductor and the like and capable of preventing deterioration due to a reaction between a lead wire and solder and a thermoelectric element, and a method for manufacturing the same.

  Conventionally, a thermoelectric element using the Peltier effect has been used as a thermoelectric element for cooling because one end generates heat and the other end absorbs heat when an electric current is passed. In particular, temperature control of laser diodes as thermoelectric modules, small size and simple structure, cooling devices without refrigerators, refrigerators, thermostats, photodetectors, electronic cooling elements such as semiconductor manufacturing equipment, temperature control of laser diodes, etc. Use is expected.

  The thermoelectric element material used for the thermoelectric module used near room temperature is a thermoelectric element made of an A2B3 type crystal (A is Bi and / or Sb, and B is Te and / or Se) from the viewpoint of excellent cooling characteristics. Is generally used.

For example, a solid solution of Bi ₂ Te ₃ (bismuth telluride) and Sb ₂ Te ₃ (antimony telluride) is used for a P-type thermoelectric element, and Bi ₂ Te ₃ and Bi ₂ Se ₃ (for a N-type thermoelectric element). Solid solutions with bismuth selenide) exhibit particularly good performance.

  As shown in FIG. 2, the thermoelectric module has wiring conductors 4 formed on the surfaces of the support substrates 1 and 2, respectively, and is joined with solder so as to sandwich the thermoelectric element 5. The thermoelectric element 5 is used as a cooling module by electrically connecting a plurality of N-type thermoelectric elements 5a and P-type thermoelectric elements 5b in series.

  The end 4a of the wiring conductor 4 was joined to the lead wire 3, and as shown in FIG. 3, the lead wire 3 and the solder 6 for joining the lead 3 wire were joined to the thermoelectric element 5 without a gap.

As a method for soldering the lead wire 3 to the wiring conductor 4, a manual method for soldering manually, or after soldering cream solder on the tip 3 a of the lead wire 3, heat melting and joining using a reflow furnace is performed. There was a heat bonding method. Further, there has been disclosed a laser joining method in which cream solder is attached to the distal end portion 3a of the lead wire 3 and then laser light is irradiated and heated for a predetermined time to solder the cream solder attaching portion of the lead wire 3 (Patent Document). 1).
JP-A-4-49678

  However, in the joining method of the lead wire 3 based on the conventional method, the lead wire 3 and the solder 6 for joining the lead 3 wire are joined to the thermoelectric element 5 without any gap by any of the methods described above. The Sn plating component of the lead wire 3, the Sn component in the solder 6, and the like react with Te of the thermoelectric element, causing problems such as deterioration in performance of the thermoelectric element 5 and inferior durability.

  Therefore, the present invention prevents the reaction between the Sn plating component of the lead wire 3 or the Sn component in the solder 6 and the thermoelectric element 5 and can improve the performance and durability of the thermoelectric element 5 and its manufacture. It aims to provide a method.

  In view of the above, the present invention provides an opposing support substrate, a plurality of thermoelectric elements that are sandwiched and arranged between the support substrates, a wiring conductor that electrically connects the plurality of thermoelectric elements, and the wiring conductor. In the thermoelectric module including a pair of solder-bonded lead wires, a gap is provided between the solder to which the lead wires are joined and the thermoelectric element.

  The gap between the solder and the thermoelectric element to which the lead wire is bonded has a shortest distance of 0.0005 to 1.5 mm.

  The gap between the lead wire and the thermoelectric element has a shortest distance of 0.0005 to 1.5 mm.

  In addition, a reaction preventing layer is filled in a gap between the solder and the thermoelectric element joined to the lead wire and / or a gap between the lead wire and the thermoelectric element.

  Also, an opposing support substrate, a plurality of thermoelectric elements arranged sandwiched between the support substrates, a wiring conductor that electrically connects the plurality of thermoelectric elements, and a pair of leads soldered to the wiring conductor In the thermoelectric module having a wire, the solder cooling rate after the solder melting of the lead wire is 5 to 50 ° C./second.

  In addition, the solder for joining the lead wires is melted using a laser beam.

  The thermoelectric module of the present invention can prevent deterioration due to the reaction between the lead wire, the solder, and the thermoelectric element by providing a gap in the lead wire, the solder, and the thermoelectric element at the joint between the lead wire and the wiring conductor.

  In particular, the above effects can be further enhanced by performing solder bonding with a laser and controlling the cooling time.

  The present invention relates to joining of lead wires in a thermoelectric module.

  As shown in FIG. 1, the thermoelectric module used for solder bonding is one in which wiring conductors 4 are formed on the surfaces of support substrates 1 and 2, respectively, and are joined with solder 7 so as to sandwich a plurality of thermoelectric elements 5. is there.

  The thermoelectric element 5 is composed of a plurality of N-type thermoelectric elements 5a and P-type thermoelectric elements 5b, which are connected by a wiring conductor 4 so that they are electrically in series, and the wiring conductor 4 is connected to the lead wire 3 and the solder 6 Is electrically connected.

In addition, the thermoelectric element 5 is preferably a sintered body mainly composed of a compound containing Bi, Sb, Te, Se, and particularly includes at least one of Bi ₂ Te ₃ , Bi ₂ Se ₃ and Sb ₂ Te _3. Is preferred. For example, Bi ₂ Te _2.85 Se _0.15 or Bi ₂ Te _2.9 Se _0. For example, Bi _0.4 Sb _1.6 Te ₃ or Bi _0.5 Sb _1.5 Te ₃ can be preferably used as the P-type thermoelectric element 5b. By selecting such a material, the risk of composition deviation is reduced, which is advantageous for obtaining a sintered body having a more uniform composition and structure.

  A Cu electrode is preferably used for the wiring conductor 4, and the solder connection with the thermoelectric element 5 is strengthened, and in order to prevent a decrease in wettability due to oxidation, the connection surface between the thermoelectric element 5 and the supporting substrates 1 and 2 is not provided. It is preferable that plating of Ni, Au or the like is formed.

  As shown in FIG. 1B, it is necessary to provide gaps W1 and W2 in the lead wire 3, the solder 6, and the thermoelectric element 5.

  In particular, the shortest distance W1 between the solder 6 to which the lead wire 3 is bonded and the thermoelectric element 5 is preferably 0.0005 to 1.5 mm.

  As a result, the thermoelectric element 5 does not react with the Sn component or the like contained in the solder 6 to which the lead wire 3 is bonded, and there is no concern that the performance of the thermoelectric element 5 is deteriorated or the durability is inferior.

  When the shortest distance W1 is narrower than 0.0005 mm, there is a problem in that the solder 6 joined to the lead wire 3 reacts with the thermoelectric element 5 so that the performance of the thermoelectric element 5 is lowered or the reliability is easily lowered. .

  On the other hand, if the shortest distance W1 is larger than 1.5 mm, the amount of solder for fixing the lead wire 3 is reduced, and the problem that the bonding strength of the lead wire 3 is likely to decrease is not preferable. Accordingly, the shortest distance W1 between the solder 6 to which the lead wire 3 is bonded and the thermoelectric element 5 is preferably 0.0005 to 1.5 mm, preferably 0.001 to 1 mm, and more preferably 0.005 to 0.005. It is good to set it as 0.05 mm.

  The shortest distance W2 between the lead wire 3 and the thermoelectric element 5 is preferably 0.0005 to 1.5 mm.

  As a result, the Sn plating component of the lead wire 3 does not react with the thermoelectric element, and there is no concern that the performance of the thermoelectric element 5 is deteriorated or the durability is inferior. In addition, when the shortest distance W2 becomes narrower than 0.0005 mm, there is a problem that the lead wire 3 and the thermoelectric element 5 react to deteriorate the performance of the thermoelectric element 5 or to reduce the reliability.

  On the other hand, when the shortest distance W2 is larger than 1.5 mm, the length that can fix the lead wire 3 is shortened, and the bonding strength of the lead wire 3 is likely to be lowered, which is not preferable. Therefore, the shortest distance W2 between the lead wire 3 and the thermoelectric element 5 is preferably 0.0005 to 1.5 mm, preferably 0.001 to 1 mm, and more preferably 0.005 to 0.05 mm. Is good.

  Note that the shortest distance W1 of the gap between the solder 6 to which the lead wire 3 is bonded and the thermoelectric element 5 and the shortest distance W2 of the gap between the lead wire 3 and the thermoelectric element 5 can be confirmed by magnifying from the side surface of the thermoelectric element 5. good. A CCD camera of about 100 times is simple, but it may be judged by performing SEM or other magnified observation.

  Further, as shown in FIG. 1C, a reaction preventing layer 8 is provided in the gap 6a between the solder 6 and the thermoelectric element 5 joined to the lead wire 3 and / or the gap 6a between the lead wire 3 and the thermoelectric element 5. It may be filled. As a result, the gap 6a can be ensured, and the performance degradation and reliability degradation problems of the thermoelectric element 5 can be prevented in advance.

  The reaction prevention layer 8 filled in the gap 6a may be a resin that can withstand the use temperature of the thermoelectric module (generally about 80 ° C.) and has high permeability. For example, a polyester resin, a silicone resin, or a polyimide resin is preferably used. it can.

  Next, the present invention relates to a support substrate 1 that is opposed, a plurality of thermoelectric elements 5 that are sandwiched and arranged between the support substrates 2, a wiring conductor 4 that electrically connects the plurality of thermoelectric elements 5, and the wiring conductor. In the thermoelectric module including the pair of lead wires 3 joined to the solder 4 to the solder 4, it is important that the cooling rate of the solder after the soldering of the lead wire 3 is 5 to 50 ° C./second, particularly preferably. The solder cooling rate is preferably 20 to 40 ° C./second.

  As a result, a gap 6 a is generated in the lead wire 3, the solder 6, and the thermoelectric element 5 in the joining of the lead wire 3 and the wiring conductor 4, thereby preventing deterioration due to the reaction of the lead wire 3, the solder 6, and the thermoelectric element 5. Can do.

Note that the cooling rate of the solder 6 is important from the melting of the solder to the fixation of the solder near the solid phase point, and here, the cooling rate in the range of 100 ° C. to the solder liquid phase temperature is defined. Note that the liquid phase point of the solder is about 240 ° C. in the case of SnSb solder with Sn = 95% by volume and Sb = 5% by volume, and about 280 ° C. in the case of AuSn solder with Au = 80% by volume and Sb = 20% by volume. Become.
By the way, when the cooling rate of the solder 6 for joining the lead wires 3 exceeds 50 ° C./second, there is a problem that the segregation of the solder 6 increases and the joining reliability of the solder 6 deteriorates. If the cooling rate of the solder 6 for joining the lead wire 3 is less than 5 ° C./second, the gap 6 a cannot be provided in the lead wire 3 and the solder 6 and the thermoelectric element 5. The method for cooling the solder 6 is preferably cooling by nitrogen blow in which nitrogen at room temperature is directly injected into the joint portion. However, if the solder is joined by laser light having a small heat capacity, it is 5 to 50 ° C. even if it is naturally cooled. It is possible to achieve a cooling rate of / sec.

  Furthermore, the solder for joining the lead wires 3 is preferably melted using a laser beam having a beam spot diameter of 0.05 to 1 mm. Thereby, only the solder joint part 6 can be heated, the characteristic deterioration of the thermoelectric element 5 can be prevented, and homogeneous solder joint can be achieved.

  On the other hand, if the beam spot diameter exceeds 1 mm, adverse effects such as deterioration of the characteristics of the thermoelectric element 5 due to overheating will occur. If the beam spot diameter is smaller than 0.05 mm, the solder 6 cannot be heated as a whole, and uniform solder joining becomes difficult.

  Note that the solder 6 at this time is preferably heated to a temperature about 50 ° C. higher than the liquid phase temperature of the solder 6. This is because if the temperature is too close to the liquidus temperature, the melting of the solder 6 becomes incomplete, and if it is too high, the solder 6 is scattered or the bonding strength is deteriorated due to oxidation. The laser output for this purpose is preferably about 20 to 50 Watt.

  Also, the solder 6 for joining the lead wire 3 advances the thread solder with respect to the joint portion 3a of the lead wire 3 at a predetermined speed in accordance with the timing of starting the laser light irradiation, and the laser light irradiation. However, it is preferable to perform a quantitative supply by a solder feeding robot in which the supply of thread solder is stopped in accordance with the completion timing of the soldering. On the other hand, a preform solder molded in a predetermined size can also be supplied in a fixed amount and can be suitably used.

  The shape of the preform solder may be a shape that wraps the lead wire 3, or may be a foil shape of about 1 × 1 × 0.05 mm that matches the end 4 a of the wiring conductor 4. Can be preferably used.

  In addition, it is preferable to irradiate the said laser beam, after apply | coating a liquid flux beforehand to the solder joint part 3a of the lead wire 3, and drying this. The component of the flux is not particularly limited, but a non-corrosive flux composed of organic compound composed of 25% rosin, 74.8% isopropyl alcohol, stearic acid and the like can be suitably used.

  As the thread solder, so-called solder containing solder containing flux may be used.

The thermoelectric module of FIG. 1 was prepared. For the thermoelectric element 5, Bi ₂ Te _2.85 Se _0.15 was used as the N-type thermoelectric element 5a, and Bi _0.4 Sb _1.6 Te ₃ was used as the P-type thermoelectric element 5b. Note that 0.09 wt% of SbI ₃ was added as a dopant to the N-type thermoelectric element 5a.

  The support substrates 1 and 2 were made of alumina ceramic having a length of 12 mm, a width of 8 mm, and a thickness of 0.3 mm. Cu is formed on the end surfaces of the supporting substrates 1 and 2 as the wiring conductor 4, and the N-type thermoelectric element 5a and the P-type thermoelectric element 5b are arranged on the wiring conductor 4 so as to be electrically in series, and the thermoelectric element Bonding was performed using solder 7 so that 5 was sandwiched between support substrates 1 and 2.

  The number of N-type thermoelectric elements 5a and P-type thermoelectric elements 5b arranged was 37 pairs.

  As solder 6 for joining the lead wire 3 to the end 4a of the wiring conductor 4, Sb—Sn or Sn—Au thread solder was used. The lead wire 3 was made of Cu as a main component and Sn plated on the surface.

  A thermoelectric module for joining such lead wires 3 was prepared, and a liquid flux was applied in advance to the tip portion 3a of the lead wires 3 to which at least the solder 6 was joined before laser light irradiation.

  As the flux, non-corrosive flux (RMA) composed of 25% rosin, 74.8% isopropyl alcohol, 0.2% organic compound composed of stearic acid or the like was used.

  The lead wire 3 was joined to the end 4 a of the wiring conductor 4 by solder 6. As a laser beam, a 30 Watt laser beam oscillated from a YAG laser was used by adjusting the beam spot diameter to φ0.3 mm.

  For the thermoelectric module thus obtained, the lead wire 3 and the gap 6a between the solder 6 and the thermoelectric element 5 were measured. The measurement was performed using a CCD camera image in which the attachment site of the lead wire 3 was magnified 100 times. Further, a thermoelectric module for investigating the effect as the reaction preventing layer 8 by filling the lead wire 3 and the gap 6a between the solder 6 and the thermoelectric element 5 with a polyester resin or a silicone resin was also manufactured.

  Next, the bonding strength of the lead wire 3 was measured. The bonding strength of the lead wire 3 is measured by an Instron universal testing machine 1125 type to determine the force required to peel off the lead wire 3 bonded to the end 4a of the wiring conductor 4 on the support substrate 1 with the solder 6. 10N or more was accepted.

The thermoelectric module performance and its reliability were also measured. The thermoelectric module performance was measured by measuring the maximum endothermic amount Qcmax as an initial value, and again measuring the maximum endothermic amount Qcmax after exposure to an atmosphere of −40 ° C. to 85 ° C. for 5000 cycles every 30 minutes, and evaluating the rate of change. . The thermoelectric module performance was measured in a 1 Pa vacuum with the heat dissipation surface of the thermoelectric module and the temperature of the cooling surface of the thermoelectric module being heated with a separately prepared heater while keeping the heat dissipation surface of the thermoelectric module at 27 ° C. This was done by measuring the heater power when they were the same. The results are shown in Table 1.

  Sample No. of the present invention. Nos. 1 to 16 had good appearance, a bonding strength of 10 N or higher, a maximum heat absorption Qcmax of 8 Watt or higher, and an excellent change rate of 5% or less.

  In particular, sample No. 1 was tested in which the shortest distance W1 between the solder 6 and the thermoelectric element 5 to which the lead wire 3 was joined and / or the shortest distance W2 between the lead wire 3 and the thermoelectric element 5 was changed. 1-12, sample No. 1 having the shortest gap distances W1 and W2 of 0.0005 to 1.5 mm. In Nos. 6 to 11, since the bonding strength of the lead wire 3 is as large as 10 N or more and the change rate of the maximum heat absorption amount is as small as 5% or less, it was found that a highly reliable thermoelectric module can be obtained.

It should be noted that sample No. 1 was tested in which a reaction preventing layer 8 was filled in the gap 6a between the solder 6 and the thermoelectric element 5 joined to the lead wire 3 and / or the gap 6a between the lead wire 3 and the thermoelectric element 5. Nos. 14 to 16 are sample Nos. With no gap 6a. Similar to 13, high bonding strength of the lead wire 3 was obtained. Sample No. 1 in which the gap 6a is filled with an insulator such as polyester resin or silicone resin having a specific resistance of 1 × 10 ¹² Ωcm or more is used. Samples Nos. 15 to 16 have no deterioration of the thermoelectric element 5 due to the reaction with the solder 6, Similar to 13, high reliability was obtained.

However, sample No. 1 in which the gap 6a was filled with a conductive resin having a specific resistance of 1 × 10 ³ Ωcm or less. No. 14 was slightly inferior in reliability.

  On the other hand, Comparative Examples 1 and 2 based on conventional knowledge have low bonding strength of the lead wire 3 and poor reliability.

The thermoelectric module of FIG. 1 was prepared. For the thermoelectric element 5, Bi ₂ Te _2.85 Se _0.15 was used as the N-type thermoelectric element 5a, and Bi _0.4 Sb _1.6 Te ₃ was used as the P-type thermoelectric element 5b. Note that 0.09 wt% of SbI ₃ was added as a dopant to the N-type thermoelectric element 5a.

  The support substrates 1 and 2 were made of alumina ceramic having a length of 12 mm, a width of 8 mm, and a thickness of 0.3 mm. Cu is formed on the end surfaces of the supporting substrates 1 and 2 as the wiring conductor 4, and the N-type thermoelectric element 5a and the P-type thermoelectric element 5b are arranged on the wiring conductor 4 so as to be electrically in series, and the thermoelectric element Bonding was performed using solder 7 so that 5 was sandwiched between support substrates 1 and 2. The number of N-type thermoelectric elements 5a and P-type thermoelectric elements 5b arranged was 37 pairs.

  As solder 6 for joining the lead wire 3 to the end 4a of the wiring conductor 4, Sb—Sn or Sn—Au thread solder was used. The lead wire 3 was made of Cu as a main component and Sn plated on the surface.

  A thermoelectric module for joining such lead wires 3 was prepared, and at least a portion 3a of the lead wires 3 to which the solder 6 was joined was previously applied with a liquid flux before laser light irradiation. As the flux, non-corrosive flux (RMA) composed of 25% rosin, 74.8% isopropyl alcohol, 0.2% organic compound composed of stearic acid or the like was used.

  The lead wire 3 was joined to the wiring conductor 4 by solder 6. As a means for solder joining, a reflow furnace or a hot plate was used in addition to the means using laser light.

  Here, an experiment was conducted on the shortest distance W1 of the gap between the solder 6 and the thermoelectric element 5 to which the lead wire 3 was joined and / or the shortest distance W2 of the gap between the lead wire 3 and the thermoelectric element 5 and the cooling rate of the solder 6. .

At this time, the irradiation time τ of the laser beam in the solder joint was set to 0.5 to 10 seconds.

  Sample No. of the present invention. 1-7 represent the shortest distance W1 between the solder 6 and the thermoelectric element 5 to which the lead wire 3 is joined and / or the shortest distance W2 between the lead wire 3 and the thermoelectric element 5 between 0.0005 and 1.5 mm. It was found that this was a good manufacturing method. In particular, the sample No. 1 with the cooling rate of the solder 6 set to 20 to 40 ° C./second. In the case of 2-3, the shortest distance W1 of the gap between the solder 6 and the thermoelectric element 5 to which the lead wire 3 is joined and / or the shortest distance W2 of the gap between the lead wire 3 and the thermoelectric element 5 is kept at 0.005 mm. Was the best.

  In this sample No. In the case of 1 to 7, the method of soldering the lead wire 3 to the wiring conductor 4 is a first step of heating the lead wire 3, the wiring conductor 4 and the solder 6, and a second step of melting and adhering to the thermoelectric element 5 The solder 6 was cooled and peeled off from the thermoelectric element 5 to form a gap 6a.

  Next, the sample No. 1 in which the test of joining the lead wire 3 by changing the beam spot diameter of the laser beam was performed. In Nos. 4 to 7, sample Nos. With a beam spot diameter of 0.03 mm were used. No. 5 is slightly low in reliability, and sample No. 5 with a beam spot diameter of 1.2 mm. 7 also had slightly lower reliability. However, the sample No. 5 was melted using a laser beam having a beam spot diameter of 0.05 to 1 mm. 4 and sample no. No. 6 was able to heat only the solder joint 6 and good reliability was obtained.

  On the other hand, in Comparative Examples 1 to 4 based on conventional knowledge, the shortest distance W1 between the solder 6 and the thermoelectric element 5 to which the lead wire 3 is joined and / or the shortest distance W2 between the lead wire 3 and the thermoelectric element 5 are used. Was inappropriate and unreliable. In the case of Comparative Examples 1 to 3, the method of soldering the lead wire 3 to the wiring conductor 4 is the first step of heating the lead wire 3, the wiring conductor 4 and the solder, and the solder melts and adheres to the thermoelectric element 5. Up to the second step, and the third step of cooling the solder and peeling from the thermoelectric element 5 to form the gap 6a is not performed, and therefore the gap 6a between the solder 6 and the thermoelectric element 5 to which the lead wire 3 is joined, and / Or there was no gap 6a between the lead wire 3 and the thermoelectric element 5.

  Furthermore, in Comparative Example 4 in which the cooling rate of the solder 6 for joining the lead wires 3 was 50 ° C./second or more, the segregation of the solder 6 was increased, and the reliability of the thermoelectric module was deteriorated.

FIG. 2 shows a solder joint portion of the thermoelectric module of the present invention, (a) an enlarged sectional view, (b) an enlarged sectional view of a gap, and (c) an enlarged sectional view of a reaction preventing layer. It is a perspective view which shows a thermoelectric module. It is sectional drawing which shows the solder joint part of the conventional thermoelectric module.

Explanation of symbols

1, 2 ... Support substrate 3a ... Lead wire tip (solder joint)
4 ... Wiring conductor 4a ... End of wiring conductor (lead wire attachment)
DESCRIPTION OF SYMBOLS 5 ... Thermoelectric element 5a ... N-type thermoelectric element 5b ... P-type thermoelectric element 6 ... Solder of the junction part of a thermoelectric element and a lead wire 6a ... Thermoelectric element, a lead wire, and / or a lead wire Solder gap 7 of the solder 7 ... Solder 8 of the junction between the thermoelectric element and the wiring conductor 8 ... Reaction prevention layer

Claims (6)

Opposing support substrate, a plurality of thermoelectric elements sandwiched and arranged between the support substrates, a wiring conductor that electrically connects the plurality of thermoelectric elements, and a pair of lead wires soldered to the wiring conductor A thermoelectric module comprising: a gap between the solder to which the lead wire is joined and the thermoelectric element. The thermoelectric module according to claim 1, wherein the gap between the solder to which the lead wire is bonded and the thermoelectric element has a shortest distance of 0.0005 to 1.5 mm. The thermoelectric module according to claim 1, wherein the gap between the lead wire and the thermoelectric element has a shortest distance of 0.0005 to 1.5 mm. 4. The thermoelectric module according to claim 1, wherein a reaction preventing layer is filled in a gap between the solder and the thermoelectric element joined to the lead wire and / or a gap between the lead wire and the thermoelectric element. . An opposing support substrate, a plurality of thermoelectric elements sandwiched and arranged between the support substrates, a wiring conductor that electrically connects the plurality of thermoelectric elements, and a pair of lead wires soldered to the wiring conductor The method of manufacturing a thermoelectric module according to claim 1, wherein a cooling rate of the solder after the lead wire solder is melted is 5 to 50 ° C./second. The method for manufacturing a thermoelectric module according to claim 5, wherein the solder for joining the lead wires is melted by using laser light.

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