Thermoelectric module

Abstract

To bypass a current when a thermoelectric circuit including a thermoelectric conversion element is disconnected with a simple and inexpensive configuration.SOLUTION: The thermoelectric module 1 includes a plurality of thermoelectric transducers 12 connected in series and each having a pair of a p-type transducer 12P and an n-type transducer 12N adjacent to each other, a resistor 33 connected in parallel to one or more pairs of a p-type transducer 12P and an n-type transducer 12N adjacent to each other, and a pair of first and second electrodes 14 and 16 that electrically connect the thermoelectric transducers 12 in series. 12a, the second electrodes 16 are disposed on the other end surface 12b of the thermoelectric transducer 12, and the resistance value of the resistor 33 is larger than the resistance value of one or more pairs of adjacent p-type device 12P and n-type device 12N.SELECTED DRAWING: Figure 3

Description

[Technical Field]

[0001] The present invention relates to a thermoelectric module. [Background technology]

[0002] Patent Document 1 discloses a technique for suppressing a decrease in output in a thermoelectric power generating device including a plurality of thermoelectric power generating elements connected in series by connecting bypass diodes to the thermoelectric power generating elements. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Application Laid-Open No. 2010-010637 Summary of the Invention [Problem to be solved by the invention]

[0004] In the technology described in Patent Document 1, bypass diodes are connected in parallel to thermoelectric power generation elements. Thermoelectric modules that require large output require a large number of thermoelectric power generation elements. Connecting diodes in parallel to each of the many thermoelectric power generation elements requires time and effort in manufacturing, increasing costs. In addition, current may flow in the reverse direction through the thermoelectric module, in which case a diode with reverse rectification properties must be added.

[0005] An aspect of the present disclosure aims to bypass current when a thermoelectric circuit including a thermoelectric conversion element is disconnected, using a simple and inexpensive configuration. [Means for solving the problem]

[0006] According to an aspect of the present disclosure, there is provided a thermoelectric module comprising: a thermoelectric conversion element having a pair of adjacent p-type and n-type elements connected in series; a resistor connected in parallel to the pair or pairs of adjacent p-type and n-type elements; and a pair of electrodes, a first electrode and a second electrode, electrically connecting the thermoelectric conversion elements in series, wherein the first electrode is disposed on one end surface of the thermoelectric conversion element and the second electrode is disposed on the other end surface of the thermoelectric conversion element; and the resistance value of the resistor is greater than the resistance value of the pair or pairs of adjacent p-type and n-type elements. [Effects of the Invention]

[0007] According to an aspect of the present disclosure, a current can be bypassed when a thermoelectric circuit including a thermoelectric conversion element is disconnected, using a simple and inexpensive configuration. [Brief explanation of the drawings]

[0008] [Figure 1] FIG. 1 is a schematic view showing a thermoelectric module according to an embodiment. [Figure 2] FIG. 2 is a cross-sectional view schematically showing the thermoelectric module according to the embodiment. [Figure 3] FIG. 3 is a cross-sectional view schematically showing a modified example of the thermoelectric module according to the embodiment. DETAILED DESCRIPTION OF THE INVENTION

[0009] Hereinafter, embodiments of the present invention will be described with reference to the drawings, but the present invention is not limited thereto. The components of the embodiments described below can be combined as appropriate. In addition, some components may not be used.

[0010] In the embodiment, the positional relationship of each part is described using the terms "left," "right," "front," "rear," "upper," and "lower." These terms indicate relative positions or directions based on the center of the thermoelectric module 1. The left-right direction, the front-rear direction, and the up-down direction are perpendicular to each other.

[0011] [Thermoelectric module] FIG. 1 is a schematic diagram showing a thermoelectric module according to an embodiment. FIG. 2 is a cross-sectional view showing a thermoelectric module according to an embodiment. The thermoelectric module 1 controls the temperature of a semiconductor substrate in a semiconductor manufacturing device, or controls the temperature of an optical component used in optical communication, for example. The thermoelectric module 1 includes a thermoelectric conversion element (thermoelectric element) 12, a first electrode 14, a second electrode 16, a first substrate 18, a second substrate 21, and a resistor 33. The arrangement of the thermoelectric conversion element 12, the first electrode 14, the second electrode 16, etc. in the drawings used in the following description is shown only schematically.

[0012] One or more thermoelectric conversion elements 12 are arranged in the thermoelectric module 1. The plurality of thermoelectric conversion elements 12 are electrically connected in series by a plurality of first electrodes 14 and second electrodes 16.

[0013] The thermoelectric conversion element 12 is formed of a thermoelectric material. Examples of thermoelectric materials that form the thermoelectric conversion element 12 include manganese silicide compounds (Mn—Si), magnesium silicide compounds (Mg—Si—Sn), skutterudite compounds (Co—Sb), half-Heusler compounds (Zr—Ni—Sn), and bismuth telluride compounds (Bi—Te). The thermoelectric conversion element 12 may be formed of one compound selected from the manganese silicide compounds, magnesium silicide compounds, skutterudite compounds, half-Heusler compounds, and bismuth telluride compounds, or may be formed of a combination of at least two compounds.

[0014] The thermoelectric conversion element 12 includes a p-type element 12P and an n-type element 12N. A plurality of the p-type elements 12P and n-type elements 12N are arranged in a predetermined plane. In the front-rear direction, the p-type elements 12P and the n-type elements 12N are arranged alternately. In the left-right direction, the p-type elements 12P and the n-type elements 12N are arranged alternately. The thermoelectric conversion element 12 has a plurality of pairs of p-type and n-type elements connected in series.

[0015] The pair of first electrode 14 and second electrode 16 are formed of a conductive metal. The first electrode 14 and second electrode 16 are formed of, for example, Cu. The first electrode 14 is disposed between the first substrate 18 and the thermoelectric conversion elements 12. The first electrode 14 and the second electrode 16 electrically connect the thermoelectric conversion elements 12 in series.

[0016] The first electrode 14 is disposed between the upper surface (one end surface) 12a of the thermoelectric conversion element 12 and the lower surface 18b of the first substrate 18. The first electrode 14 is disposed on the upper surface 12a of the thermoelectric conversion element 12. The first electrode 14 is disposed on the lower surface 18b of the first substrate 18. A plurality of first electrodes 14 are disposed in a predetermined plane parallel to the upper surface 12a of the thermoelectric conversion element 12 and the lower surface 18b of the first substrate 18.

[0017] The second electrode 16 is disposed between the thermoelectric conversion element 12 and the resistor 33. The second electrode 16 is disposed on the lower surface (the other end surface) 12b of the thermoelectric conversion element 12. The second electrode 16 is disposed on the upper surface 33a of the resistor 33.

[0018] The first electrode 14 and the second electrode 16 are connected to each of adjacent pairs of p-type element 12P and n-type element 12N. In the example of FIG. 2, adjacent pairs of p-type element 12P and n-type element 12N are connected to a single first electrode 14. Adjacent n-type element 12N and p-type element 12P connected to different first electrodes 14 are connected to a single second electrode 16. The first electrode 14 and the second electrode 16 connect multiple thermoelectric conversion elements 12 in series. The first electrode 14 and the second electrode 16 form a series circuit in which multiple thermoelectric conversion elements 12 are connected in series. The p-type element 12P and the n-type element 12N are electrically connected via the first electrode 14 and the second electrode 16 to form a pn element pair. Multiple pn element pairs are connected in series via the first electrode 14 and the second electrode 16 to form a series circuit including multiple thermoelectric conversion elements 12.

[0019] When a current is supplied to the thermoelectric conversion element 12, the thermoelectric module 1 absorbs or generates heat due to the Peltier effect. This effect is used to regulate the temperature of optical components and the like arranged above the thermoelectric module 1.

[0020] The thermoelectric conversion elements 12, the first electrodes 14, and the second electrodes 16 form a thermoelectric circuit 11. The thermoelectric circuit 11 is a circuit in which a plurality of thermoelectric conversion elements 12 are connected in series.

[0021] The first substrate 18 is a substrate that covers the upper surface of the first electrode 14 facing upward in the vertical direction. The first substrate 18 is disposed on the upper surface of the first electrode 14. The first substrate 18 is made of an electrically insulating material. Examples of electrically insulating materials include resin materials such as polyimide, and ceramics. An upper surface (one end surface) 18a of the first substrate 18 is a cooling surface (temperature control surface) of the thermoelectric module 1.

[0022] The second substrate 21 is a substrate that covers the lower surface of the resistor 33 facing downward in the vertical direction. The second substrate 21 is made of an electrically insulating material. The electrically insulating material is, for example, a highly heat-conductive resin material in which a ceramic filler is mixed into a resin material such as epoxy. The lower surface (the other end surface) 21b of the second substrate 21 is the heat dissipation surface of the thermoelectric module 1.

[0023] The first substrate 18 and the second substrate 21 are formed in a plate shape. In the embodiment, the first substrate 18 and the second substrate 21 are formed in a rectangular shape.

[0024] The resistor 33 is a resistor that forms a circuit that bypasses the current flowing through the thermoelectric conversion element 12, the first electrode 14, and the second electrode 16. The resistor 33 forms a bypass circuit that bypasses the current flowing through the thermoelectric circuit 11.

[0025] The resistor 33 is, for example, a resistor formed by etching a thin metal film such as Cu or SUS formed on the second substrate 21 serving as the base to form a circuit, or a resistor formed by printing conductive resin or conductive ceramic on the second substrate 21.

[0026] In the embodiment, one resistor 33 is arranged for each pair of adjacent p-type element 12P and n-type element 12N. The resistor 33 is electrically connected in parallel to the pair of adjacent p-type element 12P and n-type element 12N. The resistor 33 is electrically connected to two adjacent second electrodes 16. In the embodiment, the upper surface 33a of the resistor 33 is arranged on the lower surface 16b of the second electrode 16.

[0027] In the embodiment, the electrical resistance of the resistor 33 is greater than the resistance value of a pair of adjacent p-type element 12P and n-type element 12N. The electrical resistance of the resistor 33 is greater than the electrical resistance of the thermoelectric circuit 11 formed by the thermoelectric conversion element 12, the first electrode 14, and the second electrode 16, to which the resistor 33 is connected in parallel. This prevents current from flowing through the resistor 33 under normal conditions when the thermoelectric circuit 11 formed by the thermoelectric conversion element 12, the first electrode 14, and the second electrode 16 is not broken.

[0028] If any part of the thermoelectric circuit 11 is broken, a large current flows through the resistor 33, and Joule heat is generated locally in accordance with the resistor 33 and the current. For this reason, the bypass circuit using the resistor 33 must be provided on the side where a heat dissipation mechanism such as a cooling plate is located.

[0029] <effect> Next, the function of the resistor 33 according to the embodiment will be described. When a break occurs in any of the thermoelectric circuits 11 connected in series in the thermoelectric module 1, a current flows through the resistor 33 connected in parallel to the thermoelectric conversion element 12 corresponding to the broken location. As a result, the thermoelectric module 1 maintains its functions as a thermoelectric module 1, such as a temperature control function, by bypassing the current to the resistor 33 in the event of a break.

[0030] <Effects> As described above, in the embodiment, in the event of a wire breakage, current can be bypassed to the resistor 33 connected in parallel to the thermoelectric conversion element 12 corresponding to the broken location. According to the embodiment, even in the event of a wire breakage, the thermoelectric module 1 can maintain its functions, such as temperature control. According to the embodiment, current can be bypassed in the event of a wire breakage with a simple and inexpensive configuration. In this way, the embodiment can improve the life of the thermoelectric module 1 against temperature cycles.

[0031] In the embodiment, the electrical resistance of the resistor 33 is greater than the electrical resistance of the corresponding portion of the thermoelectric circuit 11 to which the resistor 33 is connected in parallel. According to the embodiment, it is possible to suppress current flow through the resistor 33 during normal operation when the thermoelectric circuit 11 is not disconnected.

[0032] [Variations] A modified example of the thermoelectric module 1 will be described using FIG. 3. FIG. 3 is a cross-sectional view schematically illustrating a modified example of the thermoelectric module according to the embodiment. In the example illustrated in FIG. 3, the connection between the resistor 33 and the second electrode 16 differs from that of the embodiment. The thermoelectric module 1 of the modified example includes a thermoelectric conversion element 12, a first electrode 14, a second electrode 16, a first substrate 18, a second substrate 21, a heat dissipation substrate 23, a resistor 33, a through hole 31, and an insulating portion 35. The thermoelectric conversion element 12, the first electrode 14, the second electrode 16, and the first substrate 18 are configured in the same manner as in the embodiment.

[0033] The second substrate 21 is disposed on the lower surface 16b of the second electrode 16. The lower surface 21b of the second substrate 21 is located below the lower surface of the resistor 33, which faces downward in the vertical direction. The second substrate 21 covers the heat dissipation substrate 23 and the resistor 33. The second substrate 21 is provided with through holes 31 that penetrate the second substrate 21 in the thickness direction and are filled with a conductor. The material of the second substrate 21 is the same as that of the embodiment.

[0034] The heat dissipation substrate 23 is a substrate that promotes heat dissipation on the second electrode 16 side. The heat dissipation substrate 23 faces the lower surface 16b of the second electrode 16 with the second substrate 21 interposed therebetween. The heat dissipation substrate 23 is disposed in the middle of the second substrate 21 in the up-down direction (thickness direction). The heat dissipation substrate 23 is formed in a plate shape. In the embodiment, the heat dissipation substrate 23 is formed in a rectangular shape similar to the first substrate 18 and the second substrate 21.

[0035] The heat dissipation substrate 23 is formed of a metal material with good thermal conductivity, such as Cu or aluminum. The heat dissipation substrate 23 may not be a metal-based substrate, but may be a substrate formed of a ceramic or resin material. A metal-based heat dissipation substrate 23 has better thermal conductivity.

[0036] The through holes 31 electrically connect the second electrode 16 and the resistor 33. The through holes 31 are holes that penetrate the second substrate 21 in the thickness direction (vertical direction). The through holes 31 are filled with a conductor such as a metal material such as Cu. The through holes 31 are arranged such that a pair of through holes 31s and 31t corresponds to a pair of p-type element 12P and n-type element 12N of the thermoelectric conversion element 12.

[0037] An upper surface 31sa of the through-hole 31s is connected to the lower surface 16b of the second electrode 16. An upper surface 31ta of the through-hole 31t is connected to the lower surface 16b of the second electrode 16.

[0038] A lower surface 31sb of the through-hole 31s is connected to an upper surface 33a of the resistor 33. A lower surface 31tb of the through-hole 31t is connected to an upper surface 33a of the resistor 33.

[0039] The resistor 33 electrically connects two adjacent second electrodes 16 via a pair of through holes 31s and 31t filled with a conductor. The resistor 33 is disposed in the middle of the second substrate 21 in the thickness direction, and is spaced further away from the second electrodes 16 than the heat dissipation substrate 23.

[0040] The insulating portion 35 is disposed so as to cover the outer peripheral surface of the through-hole 31. The insulating portion 35 is disposed on the outer periphery of the through-hole 31 below the heat dissipation substrate 23.

[0041] In the thermoelectric module 1 thus formed, the lower surface 21b side of the second substrate 21 is cooled by the cooling substrate 100. The cooling substrate 100 is a cooling plate. An upper surface 100a of the cooling substrate 100 faces the lower surface 21b of the second substrate 21.

[0042] In this modification, a bypass circuit is formed by the conductor and resistor 33 filled in the through hole 31. If a break occurs in any of the thermoelectric circuits 11 connected in series in the thermoelectric module 1, a current flows in the bypass circuit formed by the conductor and resistor 33 filled in the through hole 31, which is connected in parallel to the thermoelectric conversion element 12 corresponding to the broken location.

[0043] [Other variations] In the above description, one resistor 33 is arranged for a pair of p-type element 12P and n-type element 12N, but this is not limiting. One resistor 33 may be arranged for multiple pairs of p-type element 12P and n-type element 12N.

[0044] Although the thermoelectric module 1 used for temperature control has been described above, it can also be applied to a thermoelectric module used for thermoelectric power generation. In this case, the electrical resistance of the resistor 33 is greater than the resistance value of one or more pairs of adjacent p-type elements 12P and n-type elements 12N. [Explanation of symbols]

[0045] 1...thermoelectric module, 11...thermoelectric circuit, 12...thermoelectric conversion element, 12a...upper surface (one end surface), 12b...lower surface (other end surface), 12N...n-type element, 12Na...upper surface (one end surface), 12Nb...lower surface (other end surface), 12P...p-type element, 12Pa...upper surface (one end surface), 12Pb...lower surface (other end surface), 14...first electrode, 16...second electrode, 16b...lower surface, 18...first substrate, 18a...upper surface (one end surface), 18b...lower surface, 21...second substrate, 21b...lower surface (other end surface), 23...heat dissipation substrate, 31...through hole, 33...resistor, 33a...upper surface, 35...insulating portion, 100...cooling substrate, 100a...upper surface.

Claims

1. a plurality of thermoelectric conversion elements each having a pair of adjacent p-type and n-type elements connected in series; a resistor connected in parallel with the adjacent pair or pairs of p-type and n-type elements; a pair of electrodes, a first electrode and a second electrode, which electrically connect the thermoelectric conversion element in series; Equipped with the first electrode is disposed on one end surface of the thermoelectric conversion element, the second electrode is disposed on the other end surface of the thermoelectric conversion element, a resistance value of the resistor is greater than a resistance value of the adjacent pair or pairs of p-type elements and n-type elements; Thermoelectric module.

2. a first substrate disposed on one end surface of the first electrode; a second substrate disposed on the other end surface of the second electrode; a heat dissipation substrate disposed at a middle portion of the second substrate in a thickness direction; The thermoelectric module of claim 1 .

3. a through hole that penetrates the second substrate in a thickness direction and is filled with a conductor; Equipped with the second electrode and the resistor are electrically connected to each other through the through hole. The thermoelectric module according to claim 2 .

4. one end surface of the through hole is connected to the other end surface of the second electrode; The other end surface of the through hole is connected to one end surface of the resistor. The thermoelectric module according to claim 3 .

5. an insulating portion covering the outer peripheral surface of the through hole; The thermoelectric module of claim 3 , comprising:

6. the resistor is disposed at a middle portion of the second substrate in a thickness direction thereof so as to be spaced apart from the second electrode by more than the heat dissipation substrate. The thermoelectric module according to claim 2 or 3.

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