JP4589536B2 - Method for manufacturing thermoelectric element - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a thermoelectric element that generates electric power by a temperature difference between both ends of a thermocouple, and more particularly to a method for manufacturing a thermoelectric element that is small and includes a large number of thermocouples.
[0002]
[Prior art]
A thermocouple generates a voltage by giving a temperature difference between its two ends. A thermoelectric element uses this voltage as electric energy.
According to thermoelectric power generation using this thermoelectric element, heat energy can be directly converted into electric energy, and thus has attracted attention as an effective use method of heat energy as represented by waste heat utilization.
[0003]
As a conventional method for manufacturing a thermoelectric element, for example, DD 209545A is available.
A method for manufacturing the thermoelectric element described in this publication will be described with reference to FIGS.
[0004]
First, as shown in FIG. 10, first groove processing is performed on each of the n-type thermoelectric semiconductor block 1 and the p-type thermoelectric semiconductor block 2.
By this first groove processing, vertical grooves 16 and vertical partition walls 17 are formed in the n-type thermoelectric semiconductor block 1, and vertical grooves 26 and vertical partition walls 27 are formed in the p-type thermoelectric semiconductor block 2. The longitudinal grooves 16 and 27 are respectively performed in the middle of the thickness direction of the n-type thermoelectric semiconductor block 1 and the p-type thermoelectric semiconductor block 2, and a support portion in which the longitudinal grooves 16 and 26 are not formed is formed in each block. .
[0005]
The n-type thermoelectric semiconductor block 1 and the p-type thermoelectric semiconductor block 2 are combined such that the vertical partition wall 27 is engaged with the vertical groove 16 and the vertical partition wall 17 is engaged with the vertical groove 26, and then, as shown in FIG. The gap between the vertical partition walls 26 and the vertical partition walls 27 is filled with an epoxy adhesive, and the adhesive is cured to form an insulating resin layer 32 to form the integrated block 3.
[0006]
Next, as shown in FIG. 12, cutting is performed at the central portion of the integrated block 3 to form two separation blocks 30 and 30.
[0007]
Next, as shown in FIG. 13, the second groove processing is performed on each of the two separation blocks 30, 30 in the direction intersecting with the first groove processing to form the horizontal groove 46 and the horizontal partition wall 47.
[0008]
Next, as shown in FIG. 14, the horizontal grooves 46 and the horizontal partition walls 47 of the two separation blocks 30 and 30 are fitted to each other, and an epoxy-based adhesive is filled in the gap, and the adhesive is cured to insulate the insulating resin. Layer 32 is formed to form combination block 31.
[0009]
Next, as shown in FIG. 15, the support portion in which the upper and lower grooves of the combination block 31 are not formed is removed, and the n-type thermoelectric semiconductor element 51 and the p-type thermoelectric semiconductor element 52 are formed at the upper and lower end faces. The exposed thermoelectric element block 6 is formed.
Thereafter, the n-type thermoelectric semiconductor element 51 and the p-type thermoelectric semiconductor element 52 are connected by electrodes so as to form a thermocouple, thereby obtaining a thermoelectric element.
[0010]
[Problems to be solved by the invention]
By the way, the output voltage of a thermocouple using a BiTe material, which is said to have the highest performance index, is about 400 μV / ° C. per pair.
Since portable electronic devices are usually used near room temperature, a temperature difference inside the device cannot be expected so much.
[0011]
In the case of a wristwatch, the temperature difference inside the wristwatch caused by body temperature and outside air temperature is at most 2 ° C.
For example, in order to obtain a voltage of 1.5 V or more necessary for driving a watch, approximately 2000 or more BiTe thermocouples are required.
Furthermore, in the case of a wristwatch, the watch case is small because it is worn on the wrist, and the thermoelectric element must be housed in the watch case in addition to mechanical parts and electrical circuit parts, and the size of the thermoelectric element can be reduced. It is requested.
[0012]
In order to reduce the thermoelectric element and increase the number of thermocouples in this way, the n-type thermoelectric semiconductor element 51 and the p-type thermoelectric semiconductor element 52 embedded in the thermoelectric element block 6 are end faces of the thermoelectric element block 6. The size of the portion exposed from the substrate must be reduced, that is, refined.
When the areas of the n-type thermoelectric semiconductor element 51 and the p-type thermoelectric semiconductor element 52 are miniaturized, problems occur as described below.
[0013]
The volume of the insulating resin layer 32 made of an epoxy-based adhesive filled between the n-type thermoelectric semiconductor element 51 and the p-type thermoelectric semiconductor element 52 contracts by about several percent when cured.
When the volume of the insulating resin layer 32 contracts, stress is generated, and the n-type thermoelectric semiconductor element 51 and the p-type thermoelectric semiconductor element 52 are made of a hard and brittle BiTe-based sintered body as described above. If a crack occurs and the shrinkage stress is further increased, it will be damaged.
[0014]
For this reason, in the conventional method for manufacturing a thermoelectric element, the n-type thermoelectric semiconductor element 51 and the p-type thermoelectric semiconductor element 52 are not connected. As a result, no thermocouple is formed and no electromotive force is obtained. There are challenges.
Further, there is a problem that the n-type thermoelectric semiconductor element 51 and the p-type thermoelectric semiconductor element 52 are displaced due to contraction stress, and the electrode formation process is not connected or short-circuited, so that a predetermined electromotive force cannot be obtained. is there.
[0015]
(Object of invention)
An object of the present invention is to solve the above problems and provide a method for manufacturing a thermoelectric element having a large number of thermocouples in order to reduce the size and increase the output voltage.
[0016]
[Means for Solving the Problems]
In order to achieve the above object, the following means are employed in the method for manufacturing a thermoelectric element of the present invention.
[0017]
In the manufacturing method of the thermoelectric element of the present invention, the n-type thermoelectric semiconductor block and the p-type thermoelectric semiconductor block are fixed to the base via the stress absorbing member, respectively. Forming, and
Performing a first groove in each of the n-type thermoelectric semiconductor composite block and the p-type thermoelectric semiconductor composite block to form vertical grooves and vertical partition walls, and forming an n-type grooved block and a p-type grooved block; ,
A step of fitting the n-type grooved block and the p-type grooved block with the vertical groove and the vertical partition wall with a gap therebetween;
Forming an insulating adhesive in the gap to fix the n-type grooved block and the p-type grooved block and forming an integrated block having an insulating resin layer in the gap;
Removing the base on one end face of the integrated block;
A step of forming a lateral groove and a horizontal partition by forming a second groove in the direction where the base of the integrated block is removed and intersecting the first groove processing direction to form an integrated grooved block; When,
Forming an insulating resin layer in the lateral groove of the integrated grooved block;
Forming a thermoelectric element block having an n-type thermoelectric semiconductor element and a p-type thermoelectric element by removing the base on the other end face of the integrated grooved block;
Forming an electrode for connecting the n-type thermoelectric semiconductor element and the p-type thermoelectric semiconductor element.
It is characterized by that.
[0018]
[Action]
In the method for manufacturing a thermoelectric element of the present invention, a thermoelectric semiconductor block is fixed to a base via a stress absorbing member. Furthermore, it is preferable to form the vertical groove and the horizontal groove so as to cut into the stress absorbing member.
This stress absorbing member absorbs stress by being deformed when subjected to contraction stress generated when the insulating resin layer is cured, and prevents stress that causes cracking or breakage from being applied to the thermoelectric semiconductor block.
[0019]
In this way, the shrinkage stress during curing of the insulating resin layer is absorbed by the stress absorbing member that deforms when subjected to stress, and the stress due to volume shrinkage during curing of the insulating resin layer is not applied to the thermoelectric semiconductor, and cracks are generated. No damage will occur.
Therefore, a predetermined number of thermocouples are formed, and further, no positional deviation between the n-type thermoelectric semiconductor element and the p-type thermoelectric semiconductor element occurs, and no electrode is not connected or short-circuited in the electrode formation process. Therefore, in the present invention, it is possible to form a thermoelectric element that can obtain a predetermined electromotive force.
[0020]
Furthermore, in the method for manufacturing a thermoelectric element of the present invention, the stress absorbing member fixed to the base and the thermoelectric semiconductor block has a difference in fixing force between the two.
That is, the fixing force between the thermoelectric semiconductor block and the stress absorbing member is larger than the fixing force between the base and the stress absorbing member. For this reason, the shrinkage stress of the insulating resin layer is transmitted to the stress absorbing member, but not transmitted to the underlying base.
[0021]
In the present invention, as described above, since the stress absorbing member is firmly fixed to the thermoelectric semiconductor block from the base, when stress generated by contraction of the insulating resin layer is applied, the stress absorbing member is deformed and stress is applied. Absorb. As a result, no stress is applied to the vertical barrier ribs and the horizontal barrier ribs, and the thermoelectric semiconductor is not cracked or damaged.
For this reason, the pitch dimension error between the n-type thermoelectric semiconductor element and the p-type thermoelectric semiconductor element on the lower surface of the upper surface of the thermoelectric element is reduced, and the n-type thermoelectric semiconductor element and the p-type thermoelectric semiconductor element are not connected and short-circuited during electrode formation. The production yield is improved.
[0022]
In the thermoelectric element manufacturing method of the present invention, one base is removed before the second groove processing, and the second groove processing is performed from the side from which the base is removed to form the horizontal grooves and the horizontal partition walls. .
For this reason, the second groove processing can shorten the processing time for the thickness of the base. Further, if the stress absorbing member thereunder is removed following the base removal, the processing time can be further shortened.
[0023]
Furthermore, the thermoelectric semiconductor and the base are made of different materials, and it is necessary to set different processing conditions for the two. If the second groove processing is performed without removing the base, the manufacturing process becomes complicated. On the other hand, in the manufacturing method of the present invention, the base is removed before performing the second grooving, and the grooving can be performed on the thermoelectric semiconductor under a single processing condition, thereby simplifying the manufacturing process.
This effect is significant when a material such as glass or hard ceramics that is difficult to machine is used as a base.
[0024]
Before the end face of the thermoelectric semiconductor block is fixed to the base, the upper and lower end faces of the thermoelectric semiconductor block are smooth surfaces if the base fixing face and the surface opposite to the fixing face are polished. In the thermoelectric element manufacturing method of the present invention, the adhesion of the wiring material film in the wiring process is improved.
[0025]
Alternatively, after forming the integrated grooved block, the base may be removed, and then the electrode forming surface may be polished.
Employing such a manufacturing method has the following effects. Due to the shrinkage variation of the insulating resin layer, the electrode forming surface is slightly uneven, and when the stress absorbing member is removed, the adhesive may remain in the integrated grooved block. By polishing, the n-type thermoelectric semiconductor piece and the p-type thermoelectric semiconductor piece are completely exposed, and the surface is flattened to improve the adhesion of the electrode film.
[0026]
Furthermore, in the method for manufacturing a thermoelectric element of the present invention, the grooves in the thermoelectric semiconductor block are completely cut so as not to leave a support portion as in the prior art.
For this reason, utilization efficiency of expensive thermoelectric semiconductor materials can be improved, resources can be effectively used, and thermoelectric element costs can be reduced.
[0027]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, the manufacturing method of the thermoelectric element in the optimal embodiment of this invention is demonstrated in detail using drawing.
First, as shown in FIG. 1, an n-type thermoelectric semiconductor block 1 and a p-type thermoelectric semiconductor block 2 are prepared. In the present embodiment, a BiTeSe sintered body is used as the n-type thermoelectric semiconductor block 1, and a BiTeSb sintered body is used as the p-type thermoelectric semiconductor block 2.
[0028]
It is desirable that the n-type thermoelectric semiconductor block 1 and the p-type thermoelectric semiconductor block 2 are the same in all sizes including the thickness.
In the present embodiment, the n-type thermoelectric semiconductor block 1 and the p-type thermoelectric semiconductor block 2 are both 12 mm × 12 mm × 3 mm.
[0029]
More preferably, in the n-type thermoelectric semiconductor block 1 and the p-type thermoelectric semiconductor block 2, the upper and lower end surfaces forming the electrodes are polished to be smooth surfaces.
In the following drawings, the n-type thermoelectric semiconductor block 1 is shown with diagonal lines on the entire surface in order to easily distinguish between the two blocks of the n-type thermoelectric semiconductor block 1 and the p-type thermoelectric semiconductor block 2.
[0030]
Next, the n-type thermoelectric semiconductor block 1 is fixed to the base 10 via the stress absorbing member 11 to form an n-type thermoelectric semiconductor composite block 12.
Similarly, the p-type thermoelectric semiconductor block 2 is fixed to the base 20 via the stress absorbing member 21 to form a p-type thermoelectric semiconductor composite block 22.
Hereinafter, a method for fixing the bases 10 and 20 to the n-type thermoelectric semiconductor block 1 and the p-type thermoelectric semiconductor block 2 will be described in detail.
[0031]
As the stress-absorbing members 11 and 21 used in the present embodiment, for example, a single-sided type of product name Intellimer WS5030BL of a temperature-sensitive adhesive tape manufactured by NITTA CORPORATION is used.
In this stress absorbing member, an adhesive is formed on one surface of a polyethylene terephthalate (PET) film as a base material, and a protective film called a separator is formed on the adhesive.
[0032]
This temperature-sensitive adhesive tape decreases from 1/10 to 1/20 of the adhesive sticking force at a preset temperature (switching temperature) or higher according to external temperature changes, and can be easily peeled off. . In this embodiment, a stress absorbing member provided with an adhesive having a switching temperature of 50 ° C. was used.
The thickness of the base material constituting the stress absorbing member is 188 μm, and the thickness of the adhesive is 30 μm.
[0033]
First, after fixing the stress absorbing members 11 and 21 to the bases 10 and 20 with an adhesive, respectively, the n-type thermoelectric semiconductor block 1 and the p-type thermoelectric semiconductor block 2 are bonded to the base material of the stress absorbing member with a thermosetting adhesive. Use and stick.
[0034]
The stress absorbing members 11 and 21 are fixed to the bases 10 and 20 by peeling off the protective film and applying pressure from the substrate side using a rubber roller.
At this time, the stress absorbing members 11 and 21 are fixed to the bases 10 and 20 with sufficient care so that bubbles are not formed between the bases 10 and 20 and the stress absorbing members 11 and 21.
[0035]
For fixing the stress absorbing members 11, 21 to the n-type thermoelectric semiconductor block 1 and the p-type thermoelectric semiconductor block 2, a thermosetting adhesive is used. In this embodiment, Mitsui Toatsu Chemical Co., Ltd. The name Stratbond EH455NF was used.
This is a room temperature curable epoxy adhesive.
[0036]
In the present invention, there is a difference between the fixing force between the bases 10 and 20 and the stress absorbing members 11 and 21 and the fixing force between the stress absorbing members 11 and 21 and the thermoelectric semiconductor blocks 1 and 2. The fixing force is larger than the latter fixing force.
This is for the following reason. The fixing force between the stress absorbing members 11 and 21 and the thermoelectric semiconductor blocks 1 and 2 is increased so that the shrinkage stress is transmitted to the stress absorbing members 11 and 21 but is not transmitted to the bases 10 and 20. The stress absorbing members 11 and 21 were easily deformed when subjected to shrinkage stress during the resin layer curing.
[0037]
As the bases 10 and 20, various materials can be used as long as they have a certain degree of hardness, such as glass, ceramic, plastics, and metal.
In this embodiment, glass is used as the bases 10 and 20.
[0038]
Next, as shown in FIG. 2, the first groove processing is performed on the n-type thermoelectric semiconductor block 1 and the p-type thermoelectric semiconductor block 2.
The groove processing is performed by polishing using a wire saw or grinding using a dicing saw. In the present embodiment, polishing with a wire saw is applied, and the first groove processing is performed with a wire diameter of 105 μm and a pitch size of 200 μm. In addition, although the groove bottom surface is semicircular in wire saw processing, it is illustrated in a square shape in the following drawings.
[0039]
As a result, the n-type grooved block 13 and the p-type grooved block 13 and the p-type thermoelectric semiconductor block 1 and the p-type thermoelectric semiconductor block 2 are respectively formed with the vertical partition walls 17 and 27 having a width dimension of 90 μm and 110 μm vertical grooves 16 and 26 formed therein. A mold grooved block 23 is obtained.
[0040]
At this time, the longitudinal grooves 16 and 26 are formed halfway in the thickness direction of the base material of the stress absorbing members 11 and 21, that is, leaving a part in the thickness direction of the stress absorbing members 11 and 21.
If the stress absorbing members 11 and 21 are completely cut, the stress absorption becomes insufficient when contraction stress is applied, which is not preferable.
[0041]
In this first grooving process, the cut depth of the stress absorbing members 11 and 21 into the base material is preferably an amount slightly exceeding half of the wire diameter of 105 μm, and in this embodiment, the cut depth is 60 μm.
When this cut amount is used, the grooved blocks 13 and 23 are completely cut, and the vertical partition walls 17 and 27 can be formed in a comb shape parallel from top to bottom.
[0042]
The reason why the amount of cut of the stress absorbing members 11 and 21 into the base material is minimized is to facilitate the peeling of the stress absorbing members 11 and 21 from the integrated block, which is a process described later.
That is, when the cut amount of the stress absorbing members 11 and 21 into the base material is increased, a large amount of adhesive is formed in the grooves of the stress absorbing members 11 and 21, and the adhesive force is increased. The stress absorbing members 11 and 21 cannot be easily peeled from 2.
[0043]
At this time, in order to allow the n-type grooved block 13 and the p-type grooved block 23 to be fitted, the vertical partition walls 17 and 27 of both composite blocks 13 and 23 are comb-shaped, and the vertical groove 16 and the vertical groove In order to make the pitch dimension with the groove 26 the same and to secure an insulating adhesive space for bonding, the width of the vertical grooves 16 and 26 is made wider than the width of the vertical partition walls 17 and 27 as described above.
[0044]
Next, as shown in FIG. 3, a fitting process and a fixing process of the n-type grooved block 13 and the p-type grooved block 23 are performed.
Specifically, the n-type grooved block 13 and the p-type grooved block 23 are inserted into the vertical grooves 16 and 26 and the vertical partition walls 27 and 17 of the mating block are inserted into each other, and both are fitted together. The gap is filled with an insulating adhesive using capillary action. As this insulating adhesive, a thermosetting adhesive was used for an epoxy system, and in this embodiment, Epoxy Technology Corporation trade name EPO-TEK330 was used.
[0045]
Thereafter, a heat treatment at about 120 ° C. is performed to cure the epoxy thermosetting adhesive to form an insulating resin layer (not shown) in the gap between the vertical partition wall 17 and the vertical partition wall 27, and the n-type groove The integrated block 3 is formed by fixing the entering block 13 and the p-type grooved block 23.
[0046]
This insulating resin layer has a role of fitting and fixing the n-type grooved block 11 and the p-type grooved block 21 and between the thermoelectric semiconductors of the n-type grooved block 11 and the p-type grooved block 21. It also has the function of ensuring electrical insulation.
[0047]
In the present invention, since the inner walls of the longitudinal grooves 16 and 26 can be processed smoothly by polishing using a wire saw, the integrated block 3 before fixing is partially bonded to an epoxy insulating adhesive having a low viscosity. So that the insulating adhesive can be filled in the gaps between the vertical grooves 16 and 26 and the vertical partition walls 27 and 17 by capillary action, and there is very little air bubbles mixed in. Can be secured.
[0048]
Next, as shown in FIG. 4, the base is removed from one end face of the integrated block 3. In this embodiment, the base 20 is removed.
As a result, an integrated block 3 ′ from which the base 20 is removed is obtained.
[0049]
The base 20 is removed from the integrated block 3 while being heated to a temperature of 60 ° C.
As described above, in the present invention, since the stress absorbing members 11 and 21 in which the adhesive fixing force is reduced when the temperature is higher than the switching temperature are used, a large peeling force is not required and the base 20 is used as the stress absorbing member. 21 can be easily peeled off.
[0050]
If the base 10 fixed to the other surface of the integrated block 3 is not applied to the stress absorbing member 11 if the peeling force is not applied to the stress absorbing member 11, the state of fixing the stress absorbing member 11 and the base 10 is as follows. Maintained.
[0051]
In FIG. 4, the stress absorbing member 21 is fixed to the integrated block 3 ′. However, the stress absorbing member 21 is preferably removed from the integrated block 3 ′.
As a method of removing the stress absorbing member 21 from the integrated block 3 ′, the vertical partition wall (90 μm) is smaller than the vertical groove width (110 μm). Further, as described above, the first groove processing is performed. Since the cutting amount at is minimized, the fact that the adhesive force between the integrated block 3 ′ and the stress absorbing member 21 is weak is used.
[0052]
Next, as shown in FIG. 5, the integrated groove 3 ′ is subjected to the second groove processing to form the integrated grooved block 4.
This second grooving is performed from the end face side from which the base 20 is removed, and is performed in the longitudinal direction of the vertical partition walls 17 and 27, that is, in a direction intersecting with the first grooving.
[0053]
This second grooving can also be performed by polishing using a wire saw or grinding using a dicing saw, but in this embodiment, it is performed by polishing using a wire saw and a wire diameter of 70 μm is used. Performed at 200 μm.
As described above, since the stress absorbing member 21 is removed from the integrated block 3 ′, the wire saw processing time corresponding to the thickness of the base material of the stress absorbing member 21 can be shortened.
[0054]
The second groove processing is also preferably performed when the cutting depth of the stress absorbing member 11 into the base material is a cutting depth of about 40 μm, slightly exceeding half of the 70 μm wire diameter. The member 11 can be easily peeled off.
[0055]
As a result, the width dimension of the horizontal partition wall 47 in the integrated grooved block 4 is 125 μm,
A 75 μm lateral groove 46 is formed.
[0056]
Next, as shown in FIG. 6, an insulating resin layer 54 is formed in the lateral groove 46 formed in the integrated grooved block 4.
That is, the insulating resin layer 54 is formed by filling the lateral groove 46 of the block 4 with integrated grooves with an epoxy thermosetting adhesive as an insulating adhesive.
In the present embodiment, the insulating resin layer 54 is an epoxy technology company name.
EPO-TEK330 was used.
[0057]
Thereafter, a heat treatment at about 120 ° C. is performed to cure the epoxy thermosetting adhesive to obtain an integrated grooved block 4 ′ in which the insulating resin layer 54 is formed in the lateral groove 46.
[0058]
Next, as shown in FIG. 7, the base 10 is removed from the integrated grooved block 4 ′, the stress absorbing member 11 is further removed, and the n-type thermoelectric semiconductor element 51 and the p-type thermoelectric semiconductor element 52 shown in FIG. 8. And the thermoelectric element block 5 in which are alternately arranged.
[0059]
The removal of the base 10 and the stress absorbing member 11 is performed by the same method as the removing process of the base 20 and the stress absorbing member 21 described with reference to FIG.
[0060]
A large number of n-type thermoelectric semiconductor pieces 51 and p-type thermoelectric semiconductor pieces 52 are insulated from each other by the insulating resin layers 32 and 54 and fixed integrally therewith to the thermoelectric element block 6. The upper and lower surfaces of the p-type thermoelectric semiconductor element 52 are exposed.
[0061]
Finally, electrodes for forming electrodes on the upper and lower surfaces thereof so that the n-type thermoelectric semiconductor pieces 51 and the p-type thermoelectric semiconductor pieces 52 of the thermoelectric element block 6 shown in FIG. 8 are alternately electrically connected in series. The formation process is performed to obtain the thermoelectric element block 6 on which the electrodes shown in FIG. 9 are formed.
[0062]
FIG. 9 is a plan view showing one end face side of the thermoelectric element block 6, and electrodes are formed on the upper face side and the lower face side.
[0063]
An upper surface electrode 61a indicated by a solid circle and a lower surface electrode 62a indicated by a broken circle connect adjacent n-type thermoelectric semiconductor pieces 51 and p-type thermoelectric semiconductor pieces 52 in series to form a large number of thermocouples. Electrode.
Furthermore, the L-shaped upper surface electrode 61b and the lower surface electrode 62b are electrodes necessary at the peripheral portion of the thermoelectric element block 6, and although there is a useless meaning, n-type or p-type thermoelectric semiconductor pieces are connected in parallel. ing.
[0064]
The thermoelectric semiconductor pieces 51 and 52 are insulated from each other by the insulating adhesive layer 32 and the insulating resin layer 54.
Note that the lower surface electrodes 63 and 64 indicated by small broken circles are external voltage extraction electrodes.
[0065]
Each of these electrodes is formed by forming a gold (Au) film on the upper surface and lower surface of the thermoelectric element block 6 shown in FIG. 8 by a vacuum deposition method, a sputtering method, an electroless plating method, or the like. The gold film is patterned by technology.
[0066]
Alternatively, as another method of forming the electrode, a metal mask having an opening formed at a location where a gold film is to be formed is disposed so as to be in close contact with the thermoelectric element block 6, and the electrode is placed in the opening by vacuum deposition or sputtering. A forming method can also be applied.
[0067]
【The invention's effect】
As is apparent from the above description, according to the method for manufacturing a thermoelectric element of the present invention, the thermoelectric semiconductor member is subjected to grooving, which is precise machining, and the blocks subjected to such grooving are combined and integrated. By this process, a small and high output voltage thermoelectric element can be easily and efficiently manufactured.
[0068]
Moreover, the method for manufacturing a thermoelectric element of the present invention employs means for fixing a thermoelectric semiconductor block to the base via a stress absorbing member.
The stress absorbing member absorbs stress by deformation when subjected to contraction stress generated when the insulating resin layer is cured, and prevents stress that causes cracking or breakage from being applied to the thermoelectric semiconductor block.
[0069]
Thus, the shrinkage stress generated when the insulating resin layer is cured is absorbed by the stress absorbing member that deforms when subjected to the stress, and the stress caused by the volume shrinkage when the insulating resin layer is cured is not applied to the thermoelectric semiconductor, and cracks are generated. No damage will occur.
Therefore, a predetermined number of thermocouples are formed, and further, no positional deviation between the n-type thermoelectric semiconductor element and the p-type thermoelectric semiconductor element occurs, and no electrode is not connected or short-circuited in the electrode formation process. Therefore, in the present invention, it is possible to form a thermoelectric element that can obtain a predetermined electromotive force.
[0070]
Furthermore, in the method for manufacturing a thermoelectric element of the present invention, the stress absorbing member fixed to the base and the thermoelectric semiconductor block has a difference in fixing force between the two.
That is, the fixing force between the thermoelectric semiconductor block and the stress absorbing member is larger than the fixing force between the base and the stress absorbing member. For this reason, the shrinkage stress of the insulating resin layer is transmitted to the stress absorbing member, but not transmitted to the underlying base.
[0071]
In the method for manufacturing a thermoelectric element of the present invention, as described above, since the stress absorbing member is firmly fixed to the thermoelectric semiconductor block from the base, when stress generated by contraction of the insulating resin layer is applied, the stress absorbing member Deforms and absorbs stress. As a result, no stress is applied to the vertical barrier ribs and the horizontal barrier ribs, and the thermoelectric semiconductor is not cracked or damaged.
For this reason, the pitch dimension error between the n-type thermoelectric semiconductor element and the p-type thermoelectric semiconductor element on the lower surface of the upper surface of the thermoelectric element is reduced, and the n-type thermoelectric semiconductor element and the p-type thermoelectric semiconductor element are not connected and short-circuited during electrode formation. The production yield is improved.
[0072]
In the thermoelectric element manufacturing method of the present invention, one base is removed before the second groove processing, and the second groove processing is performed from the side from which the base is removed to form the horizontal grooves and the horizontal partition walls. .
For this reason, the second groove processing can shorten the processing time for the thickness of the base. If the stress absorbing member under the base is removed following the base removal, the processing time can be further shortened.
[0073]
Furthermore, the thermoelectric semiconductor and the base are made of different materials, and it is necessary to set different processing conditions for the two. If the second groove processing is performed without removing the base, the manufacturing process becomes complicated. On the other hand, in the manufacturing method of the present invention, the base is removed before performing the second grooving, and the grooving can be performed on the thermoelectric semiconductor under a single processing condition, thereby simplifying the manufacturing process.
This effect is significant when a material such as glass or hard ceramics that is difficult to machine is used as a base.
[0074]
Before the end face of the thermoelectric semiconductor block is fixed to the base, the upper and lower end faces of the thermoelectric semiconductor block are smooth surfaces if the base fixing face and the surface opposite to the fixing face are polished. In the thermoelectric element manufacturing method of the present invention, the adhesion of the wiring material film in the wiring process is improved.
[0075]
Alternatively, after forming the integrated grooved block, the base may be removed, and then the electrode forming surface may be polished.
Employing such a manufacturing method has the following effects. Due to the shrinkage variation of the insulating resin layer, the electrode forming surface is slightly uneven, and when the stress absorbing member is removed, the adhesive may remain in the integrated grooved block. By polishing, the n-type thermoelectric semiconductor piece and the p-type thermoelectric semiconductor piece are completely exposed, and the surface is flattened to improve the adhesion of the electrode film.
[0076]
Furthermore, in the method for manufacturing a thermoelectric element of the present invention, the grooves in the thermoelectric semiconductor block are completely cut so as not to leave a support portion as in the prior art.
For this reason, utilization efficiency of expensive thermoelectric semiconductor materials can be improved, resources can be effectively used, and thermoelectric element costs can be reduced.
[Brief description of the drawings]
FIG. 1 is a perspective view showing a method for manufacturing a thermoelectric element in an embodiment of the present invention.
FIG. 2 is a perspective view showing a method for manufacturing a thermoelectric element in an embodiment of the present invention.
FIG. 3 is a perspective view showing a method for manufacturing a thermoelectric element in an embodiment of the present invention.
FIG. 4 is a perspective view showing a method for manufacturing a thermoelectric element in an embodiment of the present invention.
FIG. 5 is a perspective view showing a method for manufacturing a thermoelectric element in an embodiment of the present invention.
FIG. 6 is a perspective view showing a method for manufacturing a thermoelectric element in an embodiment of the present invention.
FIG. 7 is a perspective view showing a method for manufacturing a thermoelectric element in an embodiment of the present invention.
FIG. 8 is a perspective view showing a method for manufacturing a thermoelectric element in an embodiment of the present invention.
FIG. 9 is a plan view showing a method for manufacturing a thermoelectric element in an embodiment of the present invention.
FIG. 10 is a perspective view showing a conventional method for manufacturing a thermoelectric element.
FIG. 11 is a perspective view showing a conventional method for manufacturing a thermoelectric element.
FIG. 12 is a perspective view showing a conventional method for manufacturing a thermoelectric element.
FIG. 13 is a perspective view showing a conventional method for manufacturing a thermoelectric element.
FIG. 14 is a perspective view showing a conventional method for manufacturing a thermoelectric element.
FIG. 15 is a perspective view showing a conventional method for manufacturing a thermoelectric element.
[Explanation of symbols]
1: n-type thermoelectric semiconductor block 2: p-type thermoelectric semiconductor block
3: Integrated block 4: Integrated grooved block
5: Thermoelectric element block 6: Thermoelectric element block
10: Base 11: Stress absorbing member
12: n-type thermoelectric semiconductor block 13: n-type grooved block
16: Vertical groove 17: Vertical partition 20: Base
21: Stress absorbing member 22: P-type thermoelectric semiconductor block
23: Block with p-type groove 26: Vertical groove
27: Vertical partition 46: Horizontal groove 47: Horizontal partition
51: n-type thermoelectric semiconductor element 52: p-type thermoelectric semiconductor element
54: Insulating resin layer

Claims (6)

The n-type thermoelectric semiconductor block and the p-type thermoelectric semiconductor block are respectively fixed to the base via a stress absorbing member in which an adhesive is formed on a base material made of a resin material. Forming a step;
Forming a vertical groove and a vertical partition wall in each of the n-type thermoelectric semiconductor composite block and the p-type thermoelectric semiconductor composite block to form an n-type grooved block and a p-type grooved block; ,
A step of fitting the n-type grooved block and the p-type grooved block with the vertical groove and the vertical partition wall with a gap therebetween;
An insulating resin layer is formed by filling the gap with an insulating adhesive and heat-treating, thereby fixing the n-type grooved block and the p-type grooved block, and integrating the insulating resin layer in the gap Forming a block;
Removing the base on one end face of the integrated block;
Forming the integrated grooved block by forming a lateral groove and a horizontal partition by performing a second groove processing on the side of the integrated block from which the base has been removed, and in a direction intersecting the first groove processing direction; When,
Forming an insulating resin layer by filling the transverse groove of the integrated grooved block with an insulating adhesive and performing a heat treatment ;
Forming a thermoelectric element block having an n-type thermoelectric semiconductor element and a p-type thermoelectric element by removing the base on the other end face of the integrated grooved block;
A method of manufacturing a thermoelectric element, comprising the step of forming an electrode connecting the n-type thermoelectric semiconductor element and the p-type thermoelectric element. Method of manufacturing a thermoelectric device according to claim 1, wherein said substrate is made of polyethylene terephthalate. 3. The method of manufacturing a thermoelectric element according to claim 1, wherein a fixing force between the n-type thermoelectric semiconductor block and the p-type thermoelectric semiconductor block and the stress absorbing member is larger than a fixing force between the base and the stress absorbing member. The n-type thermoelectric semiconductor block and the p-type thermoelectric semiconductor block and the stress absorbing member are fixed with a thermosetting adhesive,
The thermoelectric element manufacturing method according to claim 3, wherein the base and the stress absorbing member are fixed by the adhesive . The thermoelectric element manufacturing method according to claim 4 , wherein the thermosetting adhesive for fixing the n-type thermoelectric semiconductor block and the p-type thermoelectric semiconductor block to the stress absorbing member is an epoxy-based adhesive. The thermoelectric element manufacturing method according to any one of claims 1 to 5 , wherein the first and second grooving processes are cut halfway along a thickness direction of the stress absorbing member.

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