Patent Description:
<CIT> discloses a thermoelectric device according to the preamble of claim <NUM>. <CIT> discloses a thermoelectric module, which includes a first and a second substrates, plural thermoelectric elements, plural first and second metal electrodes, plural first and second solder layers, and spacers.

A thermoelectric phenomenon is a phenomenon which occurs due to movement of an electron and a hole in a material and refers to direct energy conversion between heat and electricity.

The thermoelectric device is a generic term for a device using a thermoelectric phenomenon and has a structure in which a P-type thermoelectric material and an N-type thermoelectric material are bonded between metal electrodes to form a PN junction pair.

The thermoelectric device may be classified into a device using a temperature change of an electrical resistance, a device using a Seebeck effect which is a phenomenon in which an electromotive force is generated by a temperature difference, and a device using a Peltier effect which is a phenomenon in which heat absorption or heat generation occurs due to currents.

Thermoelectric devices have been variously applied to home appliances, electronic components, communication components, and the like. For example, the thermoelectric device may be applied to a cooling device, a heating device, a power generating device, or the like. Accordingly, demands for thermoelectric performance of the thermoelectric device are further increased.

The thermoelectric device includes a substrate, an electrode, and thermoelectric legs, and a plurality of thermoelectric legs are arranged in an array shape between an upper substrate and a lower substrate, and a plurality of upper electrodes and a plurality of plurality of lower electrodes are disposed between the upper substrate and the plurality of thermoelectric legs and between the lower substrate and the plurality of thermoelectric legs, respectively. Here, the upper electrodes and the lower electrodes serially connect the thermoelectric legs.

The thermoelectric device may be assembled by a surface mount technology (SMT) which arranges thermoelectric legs in an array shape on a substrate on which a plurality of electrodes are disposed and then goes through a reflow process. Generally, a space between the lower electrodes and the thermoelectric legs and a space between the upper electrodes and the thermoelectric legs may be bonded by solder. <FIG> is a view illustrating a problem which can occur when the thermoelectric device is assembled by the SMT. Referring to <FIG>, the solder may be partially melted through the reflow process. In this case, there is no problem in arrangement between lower electrodes <NUM> and thermoelectric legs <NUM>, but a solder <NUM> at upper electrodes <NUM> is partially driven down by gravity. Accordingly, as shown in <FIG>, since a space in which the solder <NUM> is not disposed is formed between the thermoelectric legs <NUM> and the electrodes <NUM>, the thermoelectric legs <NUM> and the electrodes <NUM> cannot be bonded to each other, or as shown in <FIG>, since the solder <NUM> is driven to a center, a short circuit can be generated between a pair of thermoelectric legs <NUM>.

Meanwhile, generally, a space between the upper substrate and the upper electrodes and a space between the lower substrate and the lower electrodes may be directly bonded or adhered by an adhesion layer. When the space between the upper substrate and the upper electrodes and the space between the lower substrate and the lower electrodes are directly bonded, it is advantageous in terms of thermal conductivity in comparison with the case in which adhesion is performed by the adhesion layer, but there is a problem in that reliability is inferior due to a large thermal expansion coefficient difference between the substrate and the electrodes. Meanwhile, when the space between the upper substrate and the upper electrodes and the space between the lower substrate and the lower electrodes are adhered by the adhesion layer, the adhesion layer is deteriorated during the reflow process and thus the electrodes can be separated from the substrate.

The present invention is directed to providing an electrode structure of a thermoelectric device.

One aspect of the present invention provides a thermoelectric device including a first substrate, a plurality of P-type thermoelectric legs and a plurality of N-type thermoelectric legs alternately disposed on the first substrate, a second substrate disposed on the plurality of P-type thermoelectric legs and the plurality of N-type thermoelectric legs, a plurality of first electrodes disposed between the first substrate and the plurality of P-type thermoelectric legs and the plurality of N-type thermoelectric legs and respectively having a pair of P-type thermoelectric leg and N-type thermoelectric leg disposed therein, and a plurality of second electrodes disposed between the second substrate and the plurality of P-type thermoelectric legs and the plurality of N-type thermoelectric legs and respectively having a pair of P-type thermoelectric leg and N-type thermoelectric leg disposed therein, wherein a pair of P-type solder layer and N-type solder layer and a barrier layer disposed between the pair of P-type solder layer and N-type solder layer are disposed on each of the plurality of first electrodes, a pair of P-type solder layer and N-type solder layer and a barrier layer disposed between the pair of P-type solder layer and N-type solder layer are disposed on each of the plurality of second electrodes, each of the P-type thermoelectric legs directly comes into contact with each of the P-type solder layers, each of the N-type thermoelectric legs directly comes into contact with each of the N-type solder layers, and a melting point of the barrier layer is greater than a melting point of each of the pair of P-type solder layer and N-type solder layer. The barrier layer has an insulation property. An adhesive resin layer is further provided between the first substrate and the plurality of first electrodes.

A height of the barrier layer may be greater than a height of each of the pair of P-type solder layer and N-type solder layer.

Side surfaces of the barrier layer may come into contact with the pair of P-type solder layer and N-type solder layer.

The barrier layer may include a first region having a first height, and a second region having a second height which is lower than the first height, at least a portion of the first region may come into contact with a side surface of each of the pair of P-type solder layer and N-type solder layer, and the second region may be surrounded by the first region.

The first height may be <NUM> to <NUM> times the second height.

An area of the first region may be <NUM>% to <NUM>% of an entire area of the barrier layer.

The barrier layer may include an epoxy resin.

A plated layer may be further disposed on each of the plurality of first electrodes and the plurality of second electrodes.

The barrier layer may be directly adhered onto the plated layer.

Another embodiment does not form part of the present invention but represents background art that is useful for understanding the invention. This embodiment provides a thermoelectric device including a first substrate in which a plurality of first grooves are formed in an edge thereof, a plurality of P-type thermoelectric legs and a plurality of N-type thermoelectric legs alternately disposed on the first substrate, a second substrate disposed on the plurality of P-type thermoelectric legs and the plurality of N-type thermoelectric legs, a plurality of first electrodes disposed between the first substrate and the plurality of P-type thermoelectric legs and the plurality of N-type thermoelectric legs and respectively having a pair of P-type thermoelectric leg and N-type thermoelectric leg disposed therein, a plurality of second electrodes disposed between the second substrate and the plurality of P-type thermoelectric legs and the plurality of N-type thermoelectric legs and respectively having a pair of P-type thermoelectric leg and N-type thermoelectric leg disposed therein, and an electrode fixing member configured to fix the first substrate and the plurality of first electrodes, wherein the electrode fixing member includes a plurality of first lines disposed in a first direction, a plurality of second lines disposed in a second direction crossing the first direction, and third lines configured to extend in a direction perpendicular to the plurality of first lines and the plurality of second lines at both ends of the plurality of first lines and both ends of the plurality of second lines to be inserted into the plurality of first grooves, and each of at least some of the plurality of first lines is disposed between the pair of P-type thermoelectric leg and N-type thermoelectric leg on the plurality of first electrodes.

Each of the at least some of the plurality of first lines may be disposed to be in close contact with the plurality of first electrodes at a space between the pair of P-type thermoelectric leg and N-type thermoelectric leg.

At least some of the plurality of second lines may be disposed on an adhesion layer at spaces between the plurality of first electrodes.

A plurality of second grooves may be formed in at least some of points spaced apart from the plurality of first grooves on the first substrate at predetermined intervals, and the electrode fixing member may further include fourth lines configured to extend in the direction perpendicular to the plurality of first lines and the plurality of second lines from points spaced apart from both ends of the plurality of first lines at the predetermined intervals to be inserted into the plurality of second grooves.

A depth of each of the plurality of first grooves may be <NUM> to <NUM> times a height of the first substrate.

At least some of the plurality of first grooves may be filled with the third line and adhesives.

The electrode fixing member may be formed of an insulating material.

Still another embodiment does not form part of the present invention but represents background art that is useful for understanding the invention. This embodiment provides a thermoelectric device including a first substrate in which a plurality of first grooves are formed in an edge thereof, a plurality of P-type thermoelectric legs and a plurality of N-type thermoelectric legs alternately disposed on the first substrate, a second substrate disposed on the plurality of P-type thermoelectric legs and the plurality of N-type thermoelectric legs, a plurality of first electrodes disposed between the first substrate and the plurality of P-type thermoelectric legs and the plurality of N-type thermoelectric legs and respectively having a pair of P-type thermoelectric leg and N-type thermoelectric leg disposed therein, a plurality of second electrodes disposed between the second substrate and the plurality of P-type thermoelectric legs and the plurality of N-type thermoelectric legs and respectively having a pair of P-type thermoelectric leg and N-type thermoelectric leg disposed therein, and an electrode fixing member configured to fix the first substrate and the plurality of first electrodes, wherein the electrode fixing member includes a plurality of first lines disposed in a first direction, a plurality of second lines disposed in a second direction crossing the plurality of first lines and forming a plurality of openings, and third lines configured to extend in a direction perpendicular to the plurality of first lines and the plurality of second lines at both ends of the plurality of first lines and both ends of the plurality of second lines to be inserted into the plurality of first grooves, at least some of the plurality of first lines are disposed on the plurality of first electrodes, and the P-type thermoelectric leg disposed on one first electrode and the N-type thermoelectric leg disposed on another first electrode adjacent to the one first electrode are disposed in each of the openings.

Two first lines forming each of the openings may be disposed to be in close contact with the plurality of first electrodes, and two second lines may be disposed between the plurality of first electrodes.

According to an embodiment of the present invention, a thermoelectric device having excellent performance can be obtained. Specifically, according to the embodiment of the present invention, defects generated during a reflow process for assembling the thermoelectric device can be reduced. Further, according to the embodiment of the present invention, adhesion between electrodes and legs can be improved, and a short circuit between the thermoelectric legs due to movement of a solder can be prevented.

Further, according to the embodiment of the present invention, a thermoelectric device having excellent heat conductivity and high reliability and in which a substrate and electrodes are solidly fixed can be obtained. Accordingly, even when adhesion between the electrodes and the substrate is weakened during a high-temperature reflow process or a wiring work, separation of the electrodes from the substrate can be prevented.

Hereinafter, preferable embodiments of the present invention will be described in detail with reference to the accompanying drawings.

Further, terms used in the embodiments of the present invention (including technical and scientific terms), may be interpreted with meanings that are generally understood by those skilled in the art unless particularly defined and described, and terms which are generally used, such as terms defined in a dictionary, may be understood in consideration of their contextual meanings in the related art.

In addition, terms used in the description are provided not to limit the present invention but to describe the embodiments.

In the specification, the singular form may also include the plural form unless the context clearly indicates otherwise and may include one or more of all possible combinations of A, B, and C when disclosed as at least one (or one or more) of "A, B, and C".

In addition, terms such as first, second, A, B, (a), (b), and the like may be used to describe elements of the embodiments of the present invention.

The terms are only provided to distinguish the elements from other elements, and the essence, sequence, order, or the like of the elements are not limited by the terms.

Further, when particular elements are disclosed as being "connected," "coupled," or "linked" to other elements, the elements may include not only a case of being directly connected, coupled, or linked to other elements but also a case of being connected, coupled, or linked to other elements by elements between the elements and other elements.

In addition, when one element is disclosed as being formed "on or under" another element, the term "on or under" includes both a case in which the two elements are in direct contact with each other and a case in which at least another element is disposed between the two elements (indirectly). Further, when the term "on or under" is expressed, a meaning of not only an upward direction but also a downward direction may be included with respect to one element.

<FIG> is a cross-sectional view of the thermoelectric device, and <FIG> is a perspective view of the thermoelectric device.

Referring to <FIG> and <FIG>, a thermoelectric device <NUM> includes a lower substrate <NUM>, lower electrodes <NUM>, P-type thermoelectric legs <NUM>, N-type thermoelectric legs <NUM>, upper electrodes <NUM>, and an upper substrate <NUM>.

The lower electrodes <NUM> are disposed between the lower substrate <NUM> and lower surfaces of the P-type thermoelectric legs <NUM> and the N-type thermoelectric legs <NUM>, and the upper electrodes <NUM> are disposed between the upper substrate <NUM> and upper surfaces of the P-type thermoelectric legs <NUM> and the N-type thermoelectric legs <NUM>. Accordingly, the plurality of P-type thermoelectric legs <NUM> and the plurality of N-type thermoelectric legs <NUM> are electrically connected to each other by the lower electrodes <NUM> and the upper electrodes <NUM>. The pair of P-type thermoelectric leg <NUM> and N-type thermoelectric leg <NUM> which are disposed between the lower electrodes <NUM> and the upper electrodes <NUM> and electrically connected to each other may form a unit cell.

For example, when a voltage is applied to the lower electrodes <NUM> and the upper electrodes <NUM> through lead lines <NUM> and <NUM>, due to a Peltier effect, the substrate in which current flows from the P-type thermoelectric leg <NUM> to the N-type thermoelectric leg <NUM> absorbs heat and thus may act as a cooling part, and the substrate in which current flows from the N-type thermoelectric legs <NUM> to the P-type thermoelectric legs <NUM> is heated and thus may act as a heating part.

Here, the P-type thermoelectric legs <NUM> and the N-type thermoelectric legs <NUM> may be bismuth telluride (Bi-Te)-based thermoelectric legs including bismuth (Bi) and tellurium (Te) as main raw materials. The P-type thermoelectric leg <NUM> may be a thermoelectric leg including a bismuth telluride (Bi-Te)-based main raw material of <NUM> to <NUM> wt% including at least one among antimony (Sb), nickel (Ni), aluminum(Al), copper (Cu), silver (Ag), lead (Pb), boron (B), gallium (Ga), tellurium (Te), bismuth (Bi), and indium (In) and a compound of <NUM> to <NUM> wt% including bismuth (Bi) or tellurium (Te) on the basis of a total weight of <NUM> wt%. For example, the main raw material may be bismuth-selenium-tellurium (Bi-Se-Te) and may further include bismuth (Bi) or tellurium (Te) at <NUM> to <NUM> wt% of the total weight. The N-type thermoelectric leg <NUM> may be a thermoelectric leg including a bismuth telluride (Bi-Te)-based main raw material of <NUM> to <NUM> wt% including at least one among selenium (Se), nickel (Ni), aluminum (Al), copper (Cu), silver (Ag), lead (Pb), boron (B), gallium (Ga), tellurium (Te), bismuth (Bi), and indium (In) and a compound of <NUM> to <NUM> wt% including bismuth (Bi) or tellurium (Te) on the basis of a total weight of <NUM> wt%. For example, the main raw material may be bismuth-antimony-tellurium (Bi-Sb-Te) and may further include bismuth (Bi) or tellurium (Te) at <NUM> to <NUM> wt% of the total weight.

Each of the P-type thermoelectric leg <NUM> and the N-type thermoelectric leg <NUM> may be formed as a bulk type or a stacked type. Generally, the bulk type P-type thermoelectric leg <NUM> or the bulk type N-type thermoelectric leg <NUM> may be obtained by a process of performing heat-treatment on a thermoelectric material to manufacture an ingot, pulverizing and sieving the ingot to obtain powder for thermoelectric legs, and then sintering the powder and cutting a sintered body. The stacked type P-type thermoelectric legs <NUM> or the stacked type N-type thermoelectric legs <NUM> may be obtained by a process of coating paste including the thermoelectric material on a sheet-shaped base material to form a unit member and then stacking and cutting the unit material.

In this case, the pair of P-type thermoelectric leg <NUM> and N-type thermoelectric leg <NUM> may have the same shape and volume or different shapes and volumes. For example, since electrical conduction characteristics of the P-type thermoelectric leg <NUM> and the N-type thermoelectric leg <NUM> are different, a height or cross-sectional area of the N-type thermoelectric leg <NUM> may be formed to be different from a height or cross-sectional area of the P-type thermoelectric leg <NUM>.

The performance of the thermoelectric device according to one embodiment of the present invention may be shown by the Seebeck index. The Seebeck index (ZT) may be shown as Formula <NUM>.

Here, α is the Seebeck coefficient [V/K], σ is electrical conductivity [S/m], and α<NUM>σ is a power factor [W/mK<NUM>]. Further, T is a temperature and k is thermal conductivity [W/mK]. k may be shown as a•cp•ρ, a is thermal diffusivity [cm<NUM>/S], cp is specific heat [J/gK], and ρ is density [g/cm<NUM>].

In order to obtain the Seebeck index of the thermoelectric device, a Z value (V/K) may be measured using a Z meter, and the Seebeck index (ZT) may be calculated using the measured Z value.

According to another embodiment of the present invention, each of a P-type thermoelectric leg <NUM> and an N-type thermoelectric leg <NUM> may have a structure shown in <FIG>. Referring to <FIG>, the thermoelectric legs <NUM> and <NUM> include thermoelectric material layers <NUM> and <NUM>, first plated layers <NUM>-<NUM> and <NUM>-<NUM> respectively stacked on one surfaces of the thermoelectric material layers <NUM> and <NUM>, second plated layers <NUM>-<NUM> and <NUM>-<NUM> stacked on other surfaces disposed to face the one surfaces of the thermoelectric material layers <NUM> and <NUM>, first bonding layers <NUM>-<NUM> and <NUM>-<NUM> disposed between the thermoelectric material layers <NUM> and <NUM> and the first plated layers <NUM>-<NUM> and <NUM>-<NUM> and second bonding layers <NUM>-<NUM> and <NUM>-<NUM> disposed between the thermoelectric material layers <NUM> and <NUM> and the second plated layers <NUM>-<NUM> and <NUM>-<NUM>, and first metal layers <NUM>-<NUM> and <NUM>-<NUM> stacked on the first plated layers <NUM>-<NUM> and <NUM>-<NUM> and second metal layers <NUM>-<NUM> and <NUM>-<NUM> stacked on the second plated layers <NUM>-<NUM> and <NUM>-<NUM>.

In this case, the thermoelectric material layers <NUM> and <NUM> and the first bonding layers <NUM>-<NUM> and <NUM>-<NUM> may directly come into contact with each other, and the thermoelectric material layers <NUM> and <NUM> and the second bonding layers <NUM>-<NUM> and <NUM>-<NUM> may directly come into contact with each other. Further, the first bonding layers <NUM>-<NUM> and <NUM>-<NUM> and the first plated layers <NUM>-<NUM> and <NUM>-<NUM> may directly come into contact with each other, and the second bonding layers <NUM>-<NUM> and <NUM>-<NUM> and the second plated layers <NUM>-<NUM> and <NUM>-<NUM> may directly come into contact with each other. In addition, the first plated layers <NUM>-<NUM> and <NUM>-<NUM> and the first metal layer <NUM>-<NUM> and <NUM>-<NUM> may directly come into contact with each other, and the second plated layers <NUM>-<NUM> and <NUM>-<NUM> and the second metal layers <NUM>-<NUM> and <NUM>-<NUM> may directly come into contact with each other.

Here, each of the thermoelectric material layers <NUM> and <NUM> may include bismuth (Bi) and tellurium (Te) which are semiconductor materials. The thermoelectric material layers <NUM> and <NUM> may be formed of a material or have a shape the same as that of the P-type thermoelectric leg <NUM> or N-type thermoelectric leg <NUM> shown in FIG.

Further, the first metal layers <NUM>-<NUM> and <NUM>-<NUM> and the second metal layers <NUM>-<NUM> and <NUM>-<NUM> may each be selected from copper (Cu), a copper alloy, aluminum (Al), and an aluminum alloy, and may each have a thickness of <NUM> to <NUM>, and preferably, <NUM> to <NUM>. Since a thermal expansion coefficient of each of the first metal layers <NUM>-<NUM> and <NUM>-<NUM> and the second metal layers <NUM>-<NUM> and <NUM>-<NUM> is greater than or similar to a thermal expansion coefficient of each of the thermoelectric material layers <NUM> and <NUM>, during sintering, a compression stress is applied at an interface between the first metal layers <NUM>-<NUM> and <NUM>-<NUM> and the second metal layers <NUM>-<NUM> and <NUM>-<NUM> and the thermoelectric material layers <NUM> and <NUM>, and thus cracks or peeling may be prevented. Further, since a coupling force between the first metal layers <NUM>-<NUM> and <NUM>-<NUM> and the second metal layers <NUM>-<NUM> and <NUM>-<NUM> and the electrodes <NUM> and <NUM> is high, the thermoelectric legs <NUM> and <NUM> may be stably coupled to the electrodes <NUM> and <NUM>.

In addition, each of the first plated layers <NUM>-<NUM> and <NUM>-<NUM> and the second plated layers <NUM>-<NUM> and <NUM>-<NUM> may include at least one among Ni, Sn, Ti, Fe, Sb, Cr, and Mo and may have a thickness of <NUM> to <NUM>, and preferably, <NUM> to <NUM>. Since the first plated layers <NUM>-<NUM> and <NUM>-<NUM> and the second plated layers <NUM>-<NUM> and <NUM>-<NUM> prevent a reaction between Bi or Te which are the semiconductor materials of the thermoelectric material layers <NUM> and <NUM> and the first metal layers <NUM>-<NUM> and <NUM>-<NUM> and the second metal layers <NUM>-<NUM> and <NUM>-<NUM>, the performance degradation of the thermoelectric device may be prevented, and oxidization of the first metal layers <NUM>-<NUM> and <NUM>-<NUM> and the second metal layers <NUM>-<NUM> and <NUM>-<NUM> may also be prevented.

In this case, the first bonding layers <NUM>-<NUM> and <NUM>-<NUM> may be disposed between the thermoelectric material layers <NUM> and <NUM> and the first plated layers <NUM>-<NUM> and <NUM>-<NUM> and the second bonding layers <NUM>-<NUM> and <NUM>-<NUM> may be disposed between the thermoelectric material layers <NUM> and <NUM> and the second plated layers <NUM>-<NUM> and <NUM>-<NUM>. In this case, each of the first bonding layers <NUM>-<NUM> and <NUM>-<NUM> and the second bonding layers <NUM>-<NUM> and <NUM>-<NUM> may include Te. For example, each of the first bonding layers <NUM>-<NUM> and <NUM>-<NUM> and the second bonding layers <NUM>-<NUM> and <NUM>-<NUM> may include at least one among Ni-Te, Sn-Te, Ti-Te, Fe-Te, Sb-Te, Cr-Te and Mo-Te. According to the embodiment of the present invention, a thickness of each of the first bonding layers <NUM>-<NUM> and <NUM>-<NUM> and the second bonding layers <NUM>-<NUM> and <NUM>-<NUM> may be <NUM> to <NUM>, and preferably, <NUM> to <NUM>. According to the embodiment of the present invention, the first bonding layers <NUM>-<NUM> and <NUM>-<NUM> and second bonding layers <NUM>-<NUM> and <NUM>-<NUM> including Te may be disposed between the thermoelectric material layers <NUM> and <NUM> and the first plated layers <NUM>-<NUM> and <NUM>-<NUM> and the second plated layers <NUM>-<NUM> and <NUM>-<NUM> in advance to prevent diffusion of Te in thermoelectric material layers <NUM> and <NUM> to the first plated layers <NUM>-<NUM> and <NUM>-<NUM> and the second plated layers <NUM>-<NUM> and <NUM>-<NUM>. Accordingly, generation of a Bi rich region may be prevented.

Accordingly, a Te content is greater than a Bi content from center portions of the thermoelectric material layers <NUM> and <NUM> to interfaces between the thermoelectric material layers <NUM> and <NUM> and the first bonding layers <NUM>-<NUM> and <NUM>-<NUM>, and a Te content is greater than a Bi content from center portions of the thermoelectric material layers <NUM> and <NUM> to interfaces between the thermoelectric material layers <NUM> and <NUM> and the second bonding layers <NUM>-<NUM> and <NUM>-<NUM>. The Te content from the center portions of the thermoelectric material layers <NUM> and <NUM> to interfaces between the thermoelectric material layers <NUM> and <NUM> and the first bonding layers <NUM>-<NUM> and <NUM>-<NUM> or the Te content from the center portions of the thermoelectric material layers <NUM> and <NUM> to interfaces between the thermoelectric material layers <NUM> and <NUM> and the second bonding layers <NUM>-<NUM> and <NUM>-<NUM> may be <NUM> to <NUM> times a Te content in the center portions of the thermoelectric material layers <NUM> and <NUM>. For example, a Te content in a thickness within <NUM> in a direction from the interfaces between the thermoelectric material layers <NUM> and <NUM> and the first bonding layers <NUM>-<NUM> and <NUM>-<NUM> to the center portions of the thermoelectric material layers <NUM> and <NUM> may be <NUM> to <NUM> times the Te content in the center portions of the thermoelectric material layers <NUM> and <NUM>. Here, the Te content in the thickness within <NUM> in the direction from the interfaces between the thermoelectric material layers <NUM> and <NUM> and the first bonding layers <NUM>-<NUM> and <NUM>-<NUM> to the center portions of the thermoelectric material layers <NUM> and <NUM> may be uniformly maintained, for example, a change rate of a Te weight ratio in the thickness within <NUM> in the direction from the interfaces between the thermoelectric material layers <NUM> and <NUM> and the first bonding layers <NUM>-<NUM> and <NUM>-<NUM> to the center portions of the thermoelectric material layers <NUM> and <NUM> may be <NUM> to <NUM>.

Further, a Te content in the first bonding layers <NUM>-<NUM> and <NUM>-<NUM> or the second bonding layers <NUM>-<NUM> and <NUM>-<NUM> may be the same as or similar to the Te content in the thermoelectric material layers <NUM> and <NUM>. For example, the Te content in the first bonding layers <NUM>-<NUM> and <NUM>-<NUM> or the second bonding layers <NUM>-<NUM> and <NUM>-<NUM> may be <NUM> to <NUM> times the Te content in the thermoelectric material layers <NUM> and <NUM>, preferably, <NUM> to <NUM> times, more preferably, <NUM> to <NUM> times, and even more preferably, <NUM> to <NUM> times. Here, the content may be a weight ratio. For example, when the Te content in the thermoelectric material layers <NUM> and <NUM> is included at <NUM> wt%, the Te content in the first bonding layers <NUM>-<NUM> and <NUM>-<NUM> or the second bonding layers <NUM>-<NUM> and <NUM>-<NUM> may be <NUM> to <NUM> wt%, preferably, <NUM> to <NUM> wt%, more preferably, <NUM> to <NUM> wt%, and even more preferably, <NUM> to <NUM> wt%. Further, the Te content in the first bonding layers <NUM>-<NUM> and <NUM>-<NUM> or the second bonding layers <NUM>-<NUM> and <NUM>-<NUM> may be greater than a Ni content. The Te content in the first bonding layers <NUM>-<NUM> and <NUM>-<NUM> or the second bonding layers <NUM>-<NUM> and <NUM>-<NUM> is uniformly distributed, however, the Ni content may be reduced in the first bonding layers <NUM>-<NUM> and <NUM>-<NUM> or the second bonding layers <NUM>-<NUM> and <NUM>-<NUM> in a direction closer to the thermoelectric material layers <NUM> and <NUM>.

Further, a Te content from the interfaces between the thermoelectric material layers <NUM> and <NUM> and the first bonding layers <NUM>-<NUM> and <NUM>-<NUM> or the interfaces between the thermoelectric material layers <NUM> and <NUM> and the second bonding layers <NUM>-<NUM> and <NUM>-<NUM> to interfaces between the first plated layers <NUM>-<NUM> and <NUM>-<NUM> and the first bonding layers <NUM>-<NUM> and <NUM>-<NUM> or interfaces between the second plated layers <NUM>-<NUM> and <NUM>-<NUM> and the second bonding layers <NUM>-<NUM> and <NUM>-<NUM> may be uniformly distributed. For example, a change rate of a Te weight ratio from the interfaces between the thermoelectric material layers <NUM> and <NUM> and the first bonding layers <NUM>-<NUM> and <NUM>-<NUM> or the interfaces between the thermoelectric material layers <NUM> and <NUM> and the second bonding layers <NUM>-<NUM> and <NUM>-<NUM> to the interfaces between the first plated layers <NUM>-<NUM> and <NUM>-<NUM> and the first bonding layers <NUM>-<NUM> and <NUM>-<NUM> or the interfaces between the second plated layers <NUM>-<NUM> and <NUM>-<NUM> and the second bonding layers <NUM>-<NUM> and <NUM>-<NUM> may be <NUM> to <NUM>. Here, it may mean that the Te content from the interfaces between the thermoelectric material layers <NUM> and <NUM> and the first bonding layers <NUM>-<NUM> and <NUM>-<NUM> or the interfaces between the thermoelectric material layers <NUM> and <NUM> and the second bonding layers <NUM>-<NUM> and <NUM>-<NUM> to the interfaces between the first plated layers <NUM>-<NUM> and <NUM>-<NUM> and the first bonding layers <NUM>-<NUM> and <NUM>-<NUM> or the interfaces between the second plated layers <NUM>-<NUM> and <NUM>-<NUM> and the second bonding layers <NUM>-<NUM> and <NUM>-<NUM> may be uniformly distributed when the change rate of the Te weight ratio is close to <NUM>.

Further, a Te content in surfaces of the first bonding layers <NUM>-<NUM> and <NUM>-<NUM> which come into contact with the first plated layers <NUM>-<NUM> and <NUM>-<NUM>, that is, interfaces between the first plated layers <NUM>-<NUM> and <NUM>-<NUM> and the first bonding layers <NUM>-<NUM> and <NUM>-<NUM>, or in surfaces of the second bonding layers <NUM>-<NUM> and <NUM>-<NUM> which come into contact with the second plated layers <NUM>-<NUM> and <NUM>-<NUM>, that is, interfaces between the second plated layers <NUM>-<NUM> and <NUM>-<NUM> and the second bonding layers <NUM>-<NUM> and <NUM>-<NUM> may be <NUM> to <NUM> times, preferably, <NUM> to <NUM> times, more preferably, <NUM> to <NUM> times, and even more preferably, <NUM> to <NUM> times the Te content in surfaces of the thermoelectric material layers <NUM> and <NUM> which come into contact with the first bonding layers <NUM>-<NUM> and <NUM>-<NUM>, that is, interfaces between the thermoelectric material layers <NUM> and <NUM> and the first bonding layers <NUM>-<NUM> and <NUM>-<NUM>, in surfaces of the thermoelectric material layers <NUM> and <NUM> which come into contact with the second bonding layers <NUM>-<NUM> and <NUM>-<NUM>, that is, interfaces between the thermoelectric material layers <NUM> and <NUM> and the second bonding layers <NUM>-<NUM> and <NUM>-<NUM>. Here, the content may be a weight ratio.

Further, the Te content of the center portions of the thermoelectric material layers <NUM> and <NUM> may be the same as or similar to the Te content of the interfaces between the thermoelectric material layers <NUM> and <NUM> and the first bonding layers <NUM>-<NUM> and <NUM>-<NUM> or the interfaces between the thermoelectric material layers <NUM> and <NUM> and the second bonding layers <NUM>-<NUM> and <NUM>-<NUM>. That is, the Te content of the interfaces between the thermoelectric material layers <NUM> and <NUM> and the first bonding layers <NUM>-<NUM> and <NUM>-<NUM> or the interfaces between the thermoelectric material layers <NUM> and <NUM> and the second bonding layers <NUM>-<NUM> and <NUM>-<NUM> may be <NUM> to <NUM> times, preferably, <NUM> to <NUM> times, more preferably, <NUM> to <NUM> times, and even more preferably, <NUM> to <NUM> times the Te content of the center portions of the thermoelectric material layers <NUM> and <NUM>. Here, the content may be a weight ratio. Here, the center portions of the thermoelectric material layers <NUM> and <NUM> may refer to surrounding regions including centers of the thermoelectric material layers <NUM> and <NUM>. Further, the interfaces may refer to the interfaces themselves or may include the interfaces and regions around the interfaces which are adjacent to the interfaces within a predetermined distance.

Further, the Te content in the first plated layers <NUM>-<NUM> and <NUM>-<NUM> or the second plated layers <NUM>-<NUM> and <NUM>-<NUM> may be shown to be lower than the Te content in the thermoelectric material layers <NUM> and <NUM> or the Te content in the first bonding layers <NUM>-<NUM> and <NUM>-<NUM> or the second bonding layers <NUM>-<NUM> and <NUM>-<NUM>.

In addition, the Bi content of the center portions of the thermoelectric material layers <NUM> and <NUM> may be the same as or similar to a Bi content of the interfaces between the thermoelectric material layers <NUM> and <NUM> and the first bonding layers <NUM>-<NUM> and <NUM>-<NUM> or the interfaces between the thermoelectric material layers <NUM> and <NUM> and the second bonding layers <NUM>-<NUM> and <NUM>-<NUM>. Accordingly, since the Te content is shown to be greater than the Bi content from the center portions of the thermoelectric material layers <NUM> and <NUM> to the interfaces between the thermoelectric material layers <NUM> and <NUM> and the first bonding layers <NUM>-<NUM> and <NUM>-<NUM> or the interfaces between the thermoelectric material layers <NUM> and <NUM> and the second bonding layers <NUM>-<NUM> and <NUM>-<NUM>, an interval in which the Bi content is greater than the Te content is not present around the interfaces between the thermoelectric material layers <NUM> and <NUM> and the first bonding layers <NUM>-<NUM> and <NUM>-<NUM> or the interfaces between the thermoelectric material layers <NUM> and <NUM> and the second bonding layers <NUM>-<NUM> and <NUM>-<NUM>. For example, the Bi content of the center portions of the thermoelectric material layers <NUM> and <NUM> may be <NUM> to <NUM> times, preferably, <NUM> to <NUM> times, more preferably, <NUM> to <NUM> times, and even more preferably, <NUM> to <NUM> times the Bi content of the interfaces between the thermoelectric material layers <NUM> and <NUM> and the first bonding layers <NUM>-<NUM> and <NUM>-<NUM> or the interfaces between the thermoelectric material layers <NUM> and <NUM> and the second bonding layers <NUM>-<NUM> and <NUM>-<NUM>. Here, the content may be a weight ratio.

Here, the lower electrodes <NUM> disposed between the lower substrate <NUM> and the P-type thermoelectric leg <NUM> and the N-type thermoelectric leg <NUM>, and the upper electrodes <NUM> disposed between the upper substrate <NUM> and the P-type thermoelectric leg <NUM> and the N-type thermoelectric leg <NUM> may each include at least one among copper (Cu), silver (Ag), and nickel (Ni).

Further, the lower substrate <NUM> and the upper substrate <NUM> facing each other may be insulating substrates or metal substrates. The insulating substrate may be an alumina substrate or a polymer resin substrate having flexibility. The polymer resin substrate having flexibility may include various insulating resin materials such as polyimide (PI), polystyrene (PS), polymethyl methacrylate (PMMA), cyclic olefin copoly (COC), polyethylene terephthalate (PET), high transmission plastic such as a resin, and the like. Alternatively, the insulating substrate may also be a fabric. The metal substrate may include Cu, a Cu alloy, or a Cu-Al alloy. Further, when each of the lower substrate <NUM> and the upper substrate <NUM> are the metal substrate, a dielectric layer <NUM> may be further formed at each of a space between the lower substrate <NUM> and the lower electrodes <NUM> and a space between the upper substrate <NUM> and the upper electrodes <NUM>. The dielectric layer <NUM> may include a material having a heat conductivity of <NUM> to <NUM> W/K.

In this case, sizes of the lower substrate <NUM> and the upper substrate <NUM> may be formed to be different. For example, a volume, a thickness, or an area of one of the lower substrate <NUM> and the upper substrate <NUM> may be formed to be greater than a volume, a thickness, or an area of the other one. Accordingly, heat absorption performance or heat dissipation performance of the thermoelectric device may be improved.

Further, a heat dissipation pattern, for example, an uneven pattern, may be formed in a surface of at least one of the lower substrate <NUM> and the upper substrate <NUM>. Accordingly, the heat dissipation performance of the thermoelectric device may be improved. When the uneven pattern is formed in a surface which comes into contact with the P-type thermoelectric legs <NUM> or the N-type thermoelectric legs <NUM>, a bonding characteristic between the thermoelectric legs and the substrates may be improved.

Meanwhile, the P-type thermoelectric leg <NUM> or the N-type thermoelectric leg <NUM> may have a cylindrical shape, a polygonal pillar shape, an elliptical pillar shape, and the like.

Further, the P-type thermoelectric leg <NUM> or the N-type thermoelectric leg <NUM> may have a stacked structure. For example, the P-type thermoelectric leg <NUM> or the N-type thermoelectric leg <NUM> may be formed using a method of stacking a plurality of structures on which a semiconductor material is coated on a sheet-shaped base material and then cutting the structures. Accordingly, material loss may be prevented and an electrical conduction characteristic may be improved.

Further, the P-type thermoelectric leg <NUM> or the N-type thermoelectric leg <NUM> may be manufactured in a zone melting manner or a powder sintering manner. According to the zone melting manner, the thermoelectric legs are obtained by a method of manufacturing an ingot using a thermoelectric material, slowly applying heat to the ingot to refine the ingot so that particles are rearranged in one direction, and then slowly cooling the ingot. According to the powder sintering manner, the thermoelectric legs are obtained through a process of manufacturing an ingot using a thermoelectric material, pulverizing and sieving the ingot to obtain powder for thermoelectric legs, and then sintering the powder.

<FIG> is a cross-sectional view of a thermoelectric device according to one embodiment of the present invention, and <FIG> is a plan view of a substrate and an electrode structure of the thermoelectric device according to one embodiment of the present invention. Overlapping descriptions of contents which are the same as <FIG> and <FIG> will be omitted.

Referring to <FIG>, a thermoelectric device <NUM> includes a first substrate <NUM>, a plurality of P-type thermoelectric legs <NUM> and a plurality of N-type thermoelectric legs <NUM> alternately disposed on the first substrate <NUM>, a second substrate <NUM> disposed on the plurality of P-type thermoelectric legs <NUM> and the plurality of N-type thermoelectric legs <NUM>, a plurality of first electrodes <NUM> disposed between the first substrate <NUM> and the plurality of P-type thermoelectric legs <NUM> and the plurality of N-type thermoelectric legs <NUM>, and a plurality of second electrodes <NUM> disposed between the second substrate <NUM> and the plurality of P-type thermoelectric legs <NUM> and the plurality of N-type thermoelectric legs <NUM>.

In this case, the plurality of first electrodes <NUM> and the plurality of second electrodes <NUM> may each be disposed in an array shape of m*n (here, each of m and n may be an integer greater than or equal to <NUM>, and m and n may be the same or different), but are not limited thereto. The plurality of first electrodes <NUM> and the plurality of second electrodes <NUM> may each be disposed in the array shape of m*n, and additional first electrodes <NUM> and second electrodes <NUM> may also be disposed at edges. Each first electrode <NUM> may be disposed to be spaced apart from other first electrodes <NUM> adjacent thereto. For example, each first electrode <NUM> may be disposed to be spaced apart from other first electrodes <NUM> adjacent thereto at a distance of <NUM> to <NUM>.

Further, a pair of P-type thermoelectric leg <NUM> and N-type thermoelectric leg <NUM> may be disposed on each first electrode <NUM>, and a pair of P-type thermoelectric leg <NUM> and N-type thermoelectric leg <NUM> may be disposed on each second electrode <NUM>.

In addition, one surface of the P-type thermoelectric leg <NUM> may be disposed on the first electrode <NUM>, and the other surface of the P-type thermoelectric leg <NUM> is disposed on the second electrode <NUM>, and one surface of the N-type thermoelectric leg <NUM> may be disposed on the first electrode <NUM>, and the other surface of the N-type thermoelectric leg <NUM> may be disposed on the second electrode <NUM>. When the P-type thermoelectric leg <NUM> of the pair of P-type thermoelectric leg <NUM> and N-type thermoelectric leg <NUM> disposed on the first electrode <NUM> is disposed on one of the plurality of second electrodes <NUM>, the N-type thermoelectric leg <NUM> may be disposed on another second electrode <NUM> adjacent to the one second electrode <NUM>. Accordingly, the plurality of P-type thermoelectric legs <NUM> and the plurality of N-type thermoelectric legs <NUM> may be serially connected through the plurality of first electrodes <NUM> and the plurality of second electrodes <NUM>.

In this case, a pair of solder layers <NUM> which bonds the pair of P-type thermoelectric leg <NUM> and N-type thermoelectric leg <NUM> may be coated on the first electrode <NUM>, and the pair of P-type thermoelectric leg <NUM> and N-type thermoelectric leg <NUM> may be disposed on the pair of solder layers <NUM>. Here, the pair of solder layers <NUM> may be used with a pair of P-type solder layer and N-type solder layer, each P-type solder layer may be referred to as a solder layer which directly comes into contact with each P-type thermoelectric leg, and each N-type solder layer may be referred to as a solder layer which directly comes into contact with each N-type thermoelectric leg.

Meanwhile, the pair of P-type solder layer and N-type solder layer <NUM> may be spaced apart from each other, and a barrier layer <NUM> is disposed between the pair of P-type solder layer and N-type solder layer <NUM> on the first electrode <NUM>. In this case, the barrier layer <NUM> has an insulation performance, may have a height greater than a height of each of the pair of P-type solder layer and N-type solder layer <NUM>, and has a melting point greater than a melting point of each of the pair of P-type solder layer and N-type solder layer <NUM>.

Accordingly, when the thermoelectric legs <NUM> and <NUM> are disposed on the solder layers <NUM> and exposed to a high temperature during a reflow process to assemble the thermoelectric device <NUM>, since the barrier layer <NUM> is not melted even when the solder layers <NUM> are melted, a problem in which the solder layers <NUM> flow over the barrier layer <NUM> may be prevented. Further, even when the P-type solder layer or N-type solder layer <NUM> is partially melted and thus the P-type thermoelectric leg <NUM> or the N-type thermoelectric leg <NUM> is tilted, since the P-type thermoelectric leg <NUM> or the N-type thermoelectric leg <NUM> is blocked by the barrier layer <NUM>, a short circuit between the P-type thermoelectric leg <NUM> and the N-type thermoelectric leg <NUM> may be prevented.

<FIG> is a flow chart illustrating a method of manufacturing the thermoelectric device according to one embodiment of the present invention.

Referring to <FIG>, a plurality of first electrodes <NUM> are disposed on a first substrate <NUM> (S600). In this case, an adhesion layer may be disposed between the first substrate <NUM> and the plurality of first electrodes <NUM>. To this end, the plurality of first electrodes <NUM> may be stacked on the first substrate <NUM> after coating an adhesive on the first substrate <NUM>. Alternatively, after attaching the plurality of arranged first electrodes <NUM> to a flexible film, for example, a polyethylene (PE) film, the film may be removed after disposing the plurality of first electrodes <NUM> on the first substrate <NUM> on which the adhesive is coated in advance.

Further, a barrier layer <NUM> is printed on each of the electrodes <NUM> (S610). The barrier layer <NUM> may be printed on a middle region of each of the electrodes <NUM> and may be printed by a mask or directly printed.

Further, solder layers <NUM> are disposed on the electrodes <NUM> (S620). The solder layers <NUM> may be disposed in pairs with the barrier layer <NUM> therebetween in each of the pairs. <FIG> is a photograph illustrating a region in which a plurality of electrodes are disposed on the substrate, and then a barrier layer is printed. As shown in <FIG>, the barrier layer <NUM> may be printed in the middle region of each of the electrodes <NUM>, and the pair of solder layers <NUM> may be disposed with the barrier layer <NUM> therebetween.

In this case, a melting point of the solder layer <NUM> may be lower than a melting point of the barrier layer <NUM>. A process of operations S600 to S620 may be identically performed to manufacture the upper substrate and electrodes.

Further, thermoelectric legs <NUM> and <NUM> are disposed on the pair of solder layers <NUM> (S630), and the reflow process is performed (S640). Here, the pair of solder layers <NUM> may be used with a pair of P-type solder layer and N-type solder layer, and a P-type thermoelectric leg may be disposed on the P-type solder layer to come into contact with the P-type solder layer directly, and an N-type thermoelectric leg may be disposed on the N-type solder layer to come into contact with the N-type solder layer directly. The reflow process may be performed at a temperature greater than the melting point of the solder layer <NUM> and lower than the melting point of the barrier layer <NUM>. Accordingly, the solder layers <NUM> may be partially melted and thus the thermoelectric legs <NUM> and <NUM> may be bonded with the solder layers <NUM>, and the barrier layer <NUM> is not melted and thus it is possible to prevent a problem that the solder layers <NUM> flow over the barrier layer <NUM> or a problem of a short circuit occurring between the thermoelectric legs <NUM> and <NUM> with the barrier layer <NUM> therebetween.

Hereinafter, the embodiment of the present invention will be described in more detail.

<FIG> is a cross-sectional view of a portion of the thermoelectric device according to one embodiment of the present invention.

Referring to <FIG>, the electrode <NUM> is disposed on the substrate <NUM>, the pair of solder layers <NUM> are disposed on the electrode <NUM>, and the barrier layer <NUM> is disposed between the pair of solder layers <NUM> on the electrode <NUM>.

In this case, the substrate <NUM> and the electrode <NUM> are adhered to each other by an adhesion layer <NUM>. The adhesion layer <NUM> may include a resin composition having adhesive performance. An inorganic filler having heat conduction performance may be dispersed in the resin composition. For example, the inorganic filler may have a diameter in a range of <NUM> to <NUM> and may be formed of aluminum oxide. Accordingly, the adhesion layer <NUM> may have heat dissipation performance in addition to the adhesive performance.

In this case, as shown in <FIG>, the adhesion layer <NUM> may be coated on an entire surface of the substrate <NUM>. Alternatively, as shown in <FIG>, the adhesion layer <NUM> may be coated to be partitioned according to the electrodes <NUM> disposed to be spaced apart from each other. As described above, when the adhesion layer <NUM> is coated to be partitioned according to the electrodes <NUM>, a region on which the adhesion layer <NUM> is not disposed may be present in a portion of the substrate <NUM>, and accordingly, since the adhesion layer <NUM> is not excessively coated on the substrate <NUM>, the cooling capacity and heat dissipation characteristic of the thermoelectric device <NUM> may be maintained well. In addition, since a coating amount of the adhesion layer <NUM> may be sharply reduced, material costs may be reduced, and a short circuit due to movement of the remaining solder may be prevented.

In addition, a plated layer <NUM> may be further disposed on the electrode <NUM>, and the pair of solder layers <NUM> and the barrier layer <NUM> may be disposed on the plated layer <NUM>. The plated layer <NUM> may include nickel(Ni) or tin(Sn). When the plated layer <NUM> is disposed on the electrode layer <NUM> and then the solder layers <NUM> are disposed, since the metal layer <NUM> and the solder layers <NUM> may be bonded without thermal grease or adhesive, heat exchange efficiency between the electrode layer <NUM> and the solder layers <NUM> is improved, and it is possible to compact.

Meanwhile, according to the embodiment of the present invention, the pair of solder layers <NUM> may be disposed on the plated layer <NUM>, and the barrier layer <NUM> may be further disposed between the pair of solder layers <NUM>. The melting point of the barrier layer <NUM> is greater than the melting point of the solder layer <NUM>, and a height H2 of the barrier layer <NUM> may be greater than a height H1 of the solder layer <NUM>. Accordingly, when the reflow process is performed at a temperature between the melting point of the solder layer <NUM> and the melting point of the barrier layer <NUM>, the solder layer <NUM> is partially melted to be bonded with the thermoelectric legs <NUM> and <NUM>, and it becomes difficult for the melted solder layer <NUM> to flow over the barrier layer <NUM>. Further, in this case, since the barrier layer <NUM> is not melted, and thus the thermoelectric legs <NUM> and <NUM> are supported by the barrier layer <NUM> even when the solder layers <NUM> are excessively melted and thus a lift between the thermoelectric legs <NUM> and <NUM> and the solder layers <NUM> is generated, probability of the short circuit between the thermoelectric legs <NUM> and <NUM> being generated may be reduced.

For example, the melting point of the plated layer <NUM> may be about <NUM>, the melting point of the solder layer <NUM> may be about <NUM>, and the melting point of the barrier layer <NUM> may be about <NUM>. Further, the height H2 of the barrier layer <NUM> may be <NUM> to <NUM> times, preferably, <NUM> to <NUM> times, and more preferably, <NUM> to <NUM> times the height H1 of the solder layer <NUM>. For example, the height H2 of the barrier layer <NUM> may be about <NUM> to <NUM>, preferably, <NUM> to <NUM>, and more preferably, <NUM> to <NUM>. When a relationship between the height H2 of the barrier layer <NUM> and the height H1 of the solder layer <NUM> deviates from such ranges, the solder layers <NUM> melted through the flow process may flow over the barrier layer <NUM>, or a process of disposing the solder layers <NUM> after disposing the barrier layer <NUM> may become difficult.

In this case, side surfaces <NUM> of the barrier layer <NUM> may come into contact with the solder layers <NUM>. For example, the pair of solder layers <NUM> may be disposed adjacent to the barrier layer <NUM>, and side surfaces of the pair of solder layers <NUM> may be formed to come into contact with the side surface of the barrier layer <NUM> after the reflow process.

According to the embodiment of the present invention, the barrier layer <NUM> may be formed of an adhesive which includes an epoxy resin, has an insulation performance, and is attachable to metal. For example, the barrier layer <NUM> may have a peeling strength of <NUM> N/mm<NUM> or more at <NUM>, <NUM> N/mm<NUM> or more at <NUM>, <NUM> N/mm<NUM> or more at <NUM>, and <NUM> N/mm<NUM> or more at <NUM> with metal such as copper, aluminum, nickel, tin, and the like. As described above, when the barrier layer <NUM> has an insulation performance, the performance of the thermoelectric device <NUM> may not be influenced even when the barrier layer <NUM> comes into contact with the solder layers <NUM> or comes into contact with the thermoelectric legs <NUM> and <NUM>. Further, when the barrier layer <NUM> is formed of an adhesive attachable to the metal, the barrier layer <NUM> is directly adhered to the electrodes <NUM> or the plated layer <NUM> and thus may not be easily separated from the thermoelectric device <NUM>.

<FIG> are cross-sectional views of a portion of a thermoelectric device according to another embodiment of the present invention. Overlapping descriptions of contents the same as the contents described in <FIG> will be omitted.

Referring to <FIG>, the barrier layer <NUM> includes first regions A1 each having a first height h1 and a second region A2 having a second height h2 lower than the first height h1, wherein at least portions of the first regions A1 come into contact with the side surfaces of the pair of solder layers <NUM>, and the second region A2 is surrounded by the first regions A1. When the barrier layer <NUM> is printed in the above-described shape, printing defects may be prevented, and a problem that the melted solder layers <NUM> flow over the barrier layer <NUM> may be prevented.

For example, the first height h1 may be <NUM> to <NUM> times the second height h2, and the first region A1 may have an area of <NUM> to <NUM>% of an entire area of the barrier layer <NUM>. When the first height h1 is smaller than <NUM> times the second height h2, it is difficult for the first height h1 to serve as a barrier which prevents the solder layers <NUM> from flowing due to the first region A1, and when the first height h1 is greater than <NUM> to <NUM> times the second height h2, the first region A1 becomes fragile and thus may be easily broken. Further, when an area of the first region A1 is greater than <NUM>% of the entire area of the barrier layer <NUM>, since overall strength of the barrier layer <NUM> becomes weak, there is a problem that it is difficult to sufficiently serve as a barrier between the thermoelectric legs <NUM> and <NUM>.

Meanwhile, referring to <FIG>, not all of the side surfaces of the solder layers <NUM> may come into contact with the side surfaces of the barrier layer <NUM>, but only some of the side surfaces of the solder layers <NUM> may come into contact with the side surfaces of the barrier layer <NUM>. The above described shape may be formed in a process in which the solder layers <NUM> are partially melted and thus flow to the barrier layer <NUM> during the reflow process in the case in which the solder layers <NUM> and the barrier layer <NUM> are disposed to be spaced apart from each other when the barrier layer <NUM> is printed and then the solder layers <NUM> are disposed. As described above, in the case in which the solder layers <NUM> and the barrier layer <NUM> are disposed to be spaced apart when the solder layers <NUM> are disposed, since the solder layers <NUM> are not coated with an excessive amount of solder, a problem of the solder layers <NUM> flowing may be prevented.

In the description, although the first substrate <NUM> and the first electrodes <NUM> are mainly described for convenience of description, the same structure may be applied to the second substrate <NUM> and the second electrodes <NUM>. Alternatively, the structure according to the present disclosure may be applied to only the first substrate <NUM> and the first electrodes <NUM>, and a barrier layer may not be disposed on the second substrate <NUM> and the second electrode <NUM>, and alternatively, the structure according to the present disclosure may be applied to only the second substrate <NUM> and the second electrodes <NUM>, and a barrier layer may not be disposed on the first substrate <NUM> and the first electrodes <NUM>.

Meanwhile, <FIG> is a view illustrating an example of a substrate and an electrode structure included in the thermoelectric device, and <FIG> is a cross-sectional view of <FIG>.

A space between the lower substrate <NUM> and the lower electrodes <NUM> and a space between the upper substrate <NUM> and the upper electrodes <NUM> may be directly bonded or adhered by an adhesion layer. When the space between the lower substrate <NUM> and the lower electrodes <NUM> and the space between the upper substrate <NUM> and the upper electrodes <NUM> are directly bonded, heat conductivity is advantageous in comparison with the case of adhesion by the adhesion layer, but reliability is inferior due to a large thermal expansion coefficient difference between the substrate and the electrode.

Referring to <FIG> and <FIG>, an adhesion layer <NUM> may be coated on the lower substrate <NUM>, and a plurality of lower electrodes <NUM> may be disposed on the adhesion layer <NUM> in an array shape. Further, a pair of thermoelectric legs (not shown) may be bonded to each of the lower electrodes <NUM>. Structures of the lower substrate <NUM> and the lower electrodes <NUM> are mainly described for convenience of descriptions, but are not limited thereto, and the same structure may be applied to the upper substrate <NUM> and the upper electrodes <NUM>. In this case, the lower substrate <NUM> is a ceramic substrate and may have a heat conductivity of about <NUM> W/mK, and the lower electrodes <NUM> may have a heat conductivity of about <NUM> W/mK. When power is applied to the thermoelectric device <NUM>, although one of the upper substrate <NUM> and the lower substrate <NUM> becomes a heating surface and thus has a high probability of expansion and the other one becomes a heat absorption surface and thus has a high probability of contraction, the adhesion layer <NUM> may serve as a buffer which absorbs a thermal shock between the lower substrate <NUM> and the lower electrodes <NUM> or the upper substrate <NUM> and the upper electrodes <NUM>.

However, since the adhesion layer <NUM> is weak to heat, the adhesion layer <NUM> is degraded during a reflow process treated at a temperature of about <NUM> or more, and thus the lower electrodes <NUM> may be easily separated from the lower substrate <NUM>.

According to the embodiment of the present invention, the substrate and the electrodes will be fixed to each other using an electrode fixing member. However, the lower substrate and the lower electrodes are described as an example for convenience of description, and the same structure may be applied to the upper substrate and the upper electrodes.

<FIG> is a top view in which an electrode fixing member is disposed on a lower substrate and lower electrodes of the thermoelectric device according to one embodiment of the present invention, <FIG> is a top view of the lower substrate and the lower electrodes of the thermoelectric device according to one embodiment of the present invention, and <FIG> is a perspective view of an electrode fixing member according to one embodiment of the present invention. <FIG> is a cross-sectional view taken along line Y1 in <FIG>, <FIG> is a cross-sectional view taken along line Y2 in <FIG>, and <FIG> is a cross-sectional view taken along line X1 in <FIG>.

Referring to <FIG>, the lower electrodes <NUM> (hereinafter, may also be used as a plurality of first electrodes) are disposed on the lower substrate <NUM> (hereinafter, may also be used as a first substrate). In this case, the plurality of first electrodes <NUM> may have an array shape of m*n (here, each of m and n may be an integer greater than or equal to <NUM>), and one column may be spaced apart from another column adjacent thereto at a predetermined interval, and like the above, one row may be spaced apart from another row adjacent thereto at a predetermined interval. An adhesion layer <NUM> may be disposed between the first substrate <NUM> and the plurality of first electrodes <NUM>. A pair of N-type thermoelectric leg <NUM> and P-type thermoelectric leg <NUM> are disposed on the first electrodes <NUM>. In addition, overlapping descriptions of contents the same as the contents described in <FIG> will be omitted. Although not shown, the first electrodes <NUM> may be bonded to the pair of N-type thermoelectric leg <NUM> and P-type thermoelectric leg <NUM> by the solder layers.

According to the embodiment of the present invention, a plurality of first grooves <NUM> are formed in an edge of the first substrate <NUM>. In this case, the plurality of first grooves <NUM> are formed in the edge of the first substrate <NUM> and may be formed in points, in which the plurality of first electrodes <NUM> are not disposed, in advance. For example, the plurality of first grooves <NUM> may be formed in side surfaces of the first electrodes <NUM> forming the outermost column and the outermost row among the plurality of first electrodes <NUM>. More specifically, the plurality of first grooves <NUM> may be formed in middle points of one side surfaces in a longitudinal direction of the first electrodes <NUM> forming the outermost column and the outermost row among the plurality of first electrodes <NUM>. Here, the longitudinal direction may refer to a direction having a great length when a shape of the first electrode <NUM> is a rectangular shape, and the N-type thermoelectric legs <NUM> and the P-type thermoelectric legs <NUM> may be disposed in the longitudinal direction. That is, the middle point of one side surface in the longitudinal direction of the first electrode <NUM> may be a point corresponding to a side surface between the N-type thermoelectric leg <NUM> and the P-type thermoelectric leg <NUM>.

The thermoelectric device <NUM> according to the embodiment of the present invention further includes an electrode fixing member <NUM> which fixes the first substrate <NUM> and the plurality of first electrodes <NUM>. To this end, a portion of the electrode fixing member <NUM> may be fit into at least some of the plurality of first grooves <NUM> formed in the first substrate <NUM>, and the remaining portion of the electrode fixing member <NUM> may be disposed on the plurality of first electrodes <NUM>.

Specifically, the electrode fixing member <NUM> may include a plurality of first lines <NUM> in a first direction, a plurality of second lines <NUM> in a second direction crossing the first direction, and third lines <NUM> which extend from both ends of the plurality of first lines <NUM> and both ends of the plurality of second lines <NUM> in directions perpendicular to the plurality of first lines <NUM> and the plurality of second lines <NUM> to be inserted into the plurality of first grooves <NUM>. In this case, the plurality of first lines <NUM> and the plurality of second lines <NUM> cross each other to form a plurality of openings <NUM>. For example, the plurality of first lines <NUM> and the plurality of second lines <NUM> may form a mesh shape.

Accordingly, at least some of the plurality of first lines <NUM> are disposed on each of the plurality of first electrodes <NUM> and may be disposed between the pair of N-type thermoelectric leg <NUM> and P-type thermoelectric leg <NUM>. In this case, at least some of the plurality of first lines <NUM> may be disposed between the pair of N-type thermoelectric leg <NUM> and P-type thermoelectric leg <NUM> to be in close contact with the plurality of first electrodes <NUM>. That is, with respect to the openings <NUM>, in each of the openings <NUM>, the N-type thermoelectric leg <NUM> disposed on one first electrode <NUM> and the P-type thermoelectric leg <NUM> disposed on another first electrode <NUM> adjacent to the one first electrode <NUM> may be disposed, and the two first lines <NUM> forming the openings <NUM> may be disposed between the pair of N-type thermoelectric leg <NUM> and P-type thermoelectric leg <NUM> to be in close contact with the plurality of first electrodes <NUM>, and the two second lines <NUM> may be disposed between the plurality of first electrodes <NUM>.

As described above, when the electrode fixing member <NUM> is disposed to be in close contact with the plurality of first electrodes <NUM> and is fit into the plurality of first grooves <NUM> formed in the first substrate <NUM>, the first substrate <NUM> and the plurality of first electrodes <NUM> may be firmly fixed, and a problem that at least some of the plurality of first electrodes <NUM> are separated from the first substrate <NUM> may be prevented.

In this case, the electrode fixing member <NUM> may be formed of an insulating material. For example, the electrode fixing member <NUM> may be formed of a ceramic material, and more specifically, alumina. Accordingly, even when the electrode fixing member <NUM> is disposed to be in close contact with the plurality of first electrodes <NUM>, the electrode fixing member <NUM> may not electrically influence the thermoelectric device <NUM>.

Meanwhile, according to the embodiment of the present invention, the adhesion layer <NUM> may be further disposed between the first substrate <NUM> and the plurality of first electrodes <NUM>, and at least some of the plurality of second lines <NUM> may be disposed on the adhesion layer <NUM> between the plurality of first electrodes <NUM>. Accordingly, the mesh-shaped electrode fixing member <NUM> may have stable supporting strength and may not disturb the arrangement of the N-type thermoelectric legs <NUM> and the P-type thermoelectric legs <NUM>.

Here, the adhesion layer <NUM> may include a resin composition having adhesive performance. An inorganic filler having heat conduction performance may be dispersed in the resin composition. For example, the inorganic filler may include aluminum oxide. Accordingly, the adhesion layer <NUM> may have heat dissipation performance in addition to the adhesive performance. Further, an example in which the adhesion layer <NUM> is coated on an entire surface of the first substrate <NUM> is described, but the present invention is not limited thereto. The adhesion layer <NUM> may be disposed to be partitioned according to the plurality of first electrodes <NUM>. That is, the adhesion layer <NUM> is not disposed on the entire surface of the first substrate <NUM> but may be disposed on each of the first electrodes <NUM> which are disposed to be spaced apart from each other. Accordingly, a region on which the adhesion layer <NUM> is not disposed may present in at least a portion of the first substrate <NUM>. Since the adhesion layer <NUM> is not excessively coated on the first substrate <NUM> while serving as a buffer which absorbs a thermal shock to the first substrate <NUM>, the cooling capacity and heat dissipation characteristic of the thermoelectric device <NUM> may be well maintained. In addition, since a coating amount of the adhesion layer <NUM> may be sharply reduced, material costs may be reduced, and a short circuit due to movement of the remaining solder may be prevented.

Meanwhile, referring to <FIG>, a thickness D of each of the plurality of first lines <NUM> and the plurality of second lines <NUM> may be <NUM> to <NUM>, preferably, <NUM> to <NUM>, and more preferably, <NUM> to <NUM>. Accordingly, the electrode fixing member <NUM> may have stable supporting strength, and even when solder which bonds the first electrodes <NUM> to the N-type thermoelectric leg <NUM> or the P-type thermoelectric leg <NUM> is melted through the reflow process, a situation in which the melted solder flows to the thermoelectric leg or electrode adjacent thereto may be blocked by the plurality of first lines <NUM> and the plurality of second lines <NUM>.

Although not shown, a thickness of each of the plurality of first lines <NUM> and a thickness of each of the plurality of second lines <NUM> may be different. For example, the plurality of first lines <NUM> may are disposed on the plurality of first electrodes <NUM>, and the plurality of second lines <NUM> may be disposed between the plurality of first electrodes <NUM>. Accordingly, the thickness of each of the plurality of second lines <NUM> may be greater than the thickness of each of the plurality of first lines <NUM> by a thickness of the electrode.

Further, referring to <FIG>, a depth H2 of each of the plurality of first grooves <NUM> formed in the first substrate <NUM> may be <NUM> to <NUM> times, preferably, <NUM> to <NUM> times, and more preferably, <NUM> to <NUM> times a height H1 of the first substrate <NUM>. Accordingly, the electrode fixing member <NUM> may be stably coupled to the plurality of first grooves <NUM> formed in the first substrate <NUM>, and a problem that the third lines <NUM> of the electrode fixing member <NUM> protrude to a lower surface of the first substrate <NUM> may be prevented.

In this case, a width W1 of each of the plurality of first grooves <NUM> may be greater than a width W2 of each of the third lines <NUM>, and a tolerance between wall surfaces of the plurality of first grooves <NUM> and the third lines <NUM> may be filled with adhesives. Accordingly, the electrode fixing member <NUM> may be easily mounted in the plurality of first grooves <NUM>.

Further, referring to <FIG>, a plurality of second grooves <NUM> are further formed in at least some of points spaced apart from the plurality of first grooves <NUM> at a predetermined interval in the first substrate <NUM>, and the electrode fixing member <NUM> may further include fourth lines <NUM> which extend from points spaced apart from both ends of the plurality of first lines <NUM> at a predetermined interval in the directions perpendicular to the plurality of first lines <NUM> and the plurality of second lines <NUM> to be inserted into the plurality of second grooves <NUM>. Accordingly, the electrode fixing member <NUM> may be more stably coupled to the first substrate <NUM>. The plurality of second grooves <NUM> may be formed around, for example, a column adjacent to the outermost column or a row adjacent to the outermost row among the plurality of first electrodes <NUM>. That is, the predetermined interval may be a longitudinal interval of each of the plurality of first electrodes <NUM>. Here, the longitudinal direction may refer to a direction having a small length when a shape of the first electrode <NUM> is a rectangular shape.

<FIG> is a flow chart illustrating a method of disposing the substrate and the electrode of the thermoelectric device according to the embodiment of the present invention.

Referring to <FIG>, the plurality of grooves <NUM> and <NUM> are formed in the edge of the first substrate <NUM> (S1100). Here, a depth of each of the grooves <NUM> and <NUM> may be <NUM> to <NUM> times a height of the first substrate <NUM>.

Further, the adhesion layer <NUM> is coated on the first substrate <NUM> (S1110). Here, the adhesion layer <NUM> may include a resin composition having adhesive performance, and adhesives may flow into the grooves <NUM> and <NUM> of the first substrate <NUM>.

Further, the plurality of first electrodes <NUM> are disposed on the adhesion layer <NUM> in an array shape (S1120). In this case, the plurality of first electrodes <NUM> may have an array shape of m*n (here, each of m and n may be an integer greater than or equal to <NUM>), and one column may be spaced apart from another column adjacent thereto at a predetermined interval, and like the above, one row may be spaced apart from another row adjacent thereto at a predetermined interval.

In addition, the electrode fixing member <NUM> is disposed on the array-shaped plurality of first electrodes <NUM> and then pressurized (S1130). In this case, the third lines <NUM> and the fourth lines <NUM> of the electrode fixing member <NUM> may be inserted into the grooves <NUM> and <NUM> of the first substrate <NUM>, and the first lines <NUM> may be disposed at middle points in the longitudinal direction of the first electrode <NUM>, that is, between a region in which the N-type thermoelectric legs <NUM> are disposed and a region in which the P-type thermoelectric leg <NUM> are disposed. Accordingly, the electrode fixing member <NUM> may firmly fix the first substrate <NUM> and the plurality of first electrodes <NUM>.

Here, in the description, the embodiment in which the barrier layer is disposed on the electrodes according to <FIG> and the embodiment in which the electrode fixing member is disposed on the electrode according to <FIG> are separately described, but the embodiments may be combined with each other.

For example, a portion of the electrode fixing member disposed on the electrode according to <FIG> may be the barrier layer disposed on the electrodes according to <FIG>. Alternatively, the electrode fixing member according to <FIG> may be further disposed on the electrodes on which the barrier layer is disposed according to <FIG>.

Hereinafter, an example in which the thermoelectric device according to the embodiment of the present invention is applied to a water purifier will be described with reference to <FIG>.

<FIG> is a block diagram of a water purifier to which the thermoelectric device according to the embodiment of the present invention is applied.

A water purifier <NUM> to which the thermoelectric device according to the embodiment of the present invention is applied includes a raw water supply pipe 12a, a purified water tank introduction pipe 12b, a purified water tank <NUM>, a filter assembly <NUM>, a cooling fan <NUM>, a heat storage tank <NUM>, a cold water supply pipe 15a, and a thermoelectric apparatus <NUM>.

The raw water supply pipe 12a is a supply pipe which introduces water to be purified into the filter assembly <NUM> from a water source, the purified water tank introduction pipe 12b is an introduction pipe which introduces the water purified from the filter assembly <NUM> into the purified water tank <NUM>, and the cold water supply pipe 15a is a supply pipe from which cold water cooled in the purified water tank <NUM> by thermoelectric apparatus <NUM> by a predetermined temperature is supplied to a user.

The purified water tank <NUM> temporarily accommodates the purified water so that the water purified through the filter assembly <NUM> and introduced through the purified water tank introduction pipe 12b is stored and supplied to the outside.

The filter assembly <NUM> is composed of a sediment filter 13a, a pre carbon filter 13b, a membrane filter 13c, and a post carbon filter 13d.

That is, water introduced into the raw water supply pipe 12a may be purified through the filter assembly <NUM>.

The heat storage tank <NUM> is disposed between the purified water tank <NUM> and the thermoelectric apparatus <NUM>, cold air formed from the thermoelectric apparatus <NUM> is stored in the heat storage tank <NUM>. The cold air stored in the heat storage tank <NUM> is transferred to the purified water tank <NUM> and cools the water accommodated in the purified water tank <NUM>.

For smooth cold air transference, the heat storage tank <NUM> may come into surface contact with the purified water tank <NUM>.

As described above, the thermoelectric apparatus <NUM> is provided with a heat absorption surface and a heating surface, wherein one side is cooled and the other side is heated due to electron movement on a P-type semiconductor and an N-type semiconductor.

Here, the one side may be a side at the purified water tank <NUM>, and the other side may be a side opposite the purified water tank <NUM>.

Further, as described above, since the thermoelectric apparatus <NUM> exhibits excellent waterproof and dustproof performance and has the improved heat flow performance, the thermoelectric apparatus <NUM> may efficiently cool the purified water tank <NUM> in the water purifier.

Hereinafter, an example in which the thermoelectric device according to the embodiment of the present invention is applied to a refrigerator will be described with reference to <FIG>.

<FIG> is a block diagram of a refrigerator to which the thermoelectric device according to the embodiment of the present invention is applied.

The refrigerator includes a deep evaporation chamber cover <NUM>, an evaporation chamber partition wall <NUM>, a main evaporator <NUM>, a cooling fan <NUM>, and a thermoelectric apparatus <NUM> in a deep evaporation chamber.

The inside of the refrigerator is portioned into a deep storage chamber and the deep evaporation chamber by the deep evaporation chamber cover <NUM>.

Specifically, an inner space which is a front of the deep evaporation chamber cover <NUM> may be defined as the deep storage chamber, and an inner space which is a rear of the deep evaporation chamber cover <NUM> may be defined as the deep evaporation chamber.

A discharge grill 23a and a suction grill 23b may be formed in a front surface of the deep evaporation chamber cover <NUM>.

The evaporation chamber partition wall <NUM> is installed at a point spaced apart from a back wall of an inner cabinet in a frontward direction to partition a space in which a deep storage chamber system is placed and a space in which the main evaporator <NUM> is placed.

Cold air cooled by the main evaporator <NUM> is supplied to a freezer compartment and then returns to the main evaporator.

The thermoelectric apparatus <NUM> is accommodated in the deep evaporation chamber and forms a structure of which a heat absorption surface faces a drawer assembly of the deep storage chamber and a heating surface faces the evaporator. Accordingly, a heat absorption phenomenon which occurs in the thermoelectric apparatus <NUM> may be used to quickly cool food stored in the drawer assembly in an ultra-low temperature below a temperature of <NUM>.

Further, as described above, since the thermoelectric apparatus <NUM> exhibits excellent waterproof and dustproof performance and has the improved heat flow performance, the drawer assembly may be efficiently cooled in the refrigerator.

The thermoelectric device according to the embodiment of the present invention may be applied to a power generation device, a cooling device, a heating device, and the like. Specifically, the thermoelectric device according to the embodiment of the present invention may be mainly applied to an optical communication module, a sensor, a medical device, a measuring device, the aerospace industry, a refrigerator, a chiller, an automotive ventilation seat, a cup holder, a washing machine, a dryer, a wine cellar, a water purifier, a power supply device for a sensor, a thermopile, and the like. Alternatively, the thermoelectric device according to the embodiment of the present invention may be applied to a power generation device that generates electricity using waste heat generated from an engine of an automobile, a ship, or the like.

Here, a polymerase chain reaction (PCR) device is an example in which the thermoelectric device according to the embodiment of the present invention is applied to a medical device. The PCR device is equipment which determines a deoxyribonucleic acid (DNA) base sequence by amplifying DNA and is a device which demands precise temperature control and requires a thermal cycle. To this end, a Peltier-based thermoelectric device may be applied.

A photo detector is another example in which the thermoelectric device according to the embodiment of the present invention is applied to the medical device. Here, the photo detector includes devices such as infrared/ultraviolet detectors, charge coupled device (CCD) sensors, X-ray detectors, thermoelectric thermal reference sources (TTRS), and the like. The Peltier-based thermoelectric device may be applied to cool the photo detector. Accordingly, a wavelength change, an output decrease, and a resolution decrease, and the like due to a temperature increase in the photo detector may be prevented.

Another example in which the thermoelectric device according to the embodiment of the present invention is applied to the medical device includes an immunoassay field, an in vitro diagnostics field, general temperature control and cooling systems, physiotherapy, a liquid chiller system, a blood/plasma temperature control field, and the like. Accordingly, precise temperature control may be performed.

Still another example in which the thermoelectric device according to the embodiment of the present invention is applied to the medical device includes an artificial heart. Accordingly, power may be supplied to the artificial heart.

An example in which the thermoelectric device according to the embodiment of the present invention is applied to the aerospace industry includes a star tracking system, a thermal imaging camera, an infrared/ultraviolet detector, a CCD sensor, the Hubble Space Telescope, a target tracking radar (TTRS), and the like. Accordingly, the temperature of an image sensor may be maintained.

Another example in which the thermoelectric device according to the embodiment of the present invention is applied to the aerospace industry includes a cooling device, a heater, a power generation device, and the like.

In addition, the thermoelectric device according to the embodiment of the present invention may be applied to other industrial fields for power generation, cooling, and warming.

Claim 1:
A thermoelectric device (<NUM>) comprising:
a first substrate (<NUM>);
a plurality of P-type thermoelectric legs (<NUM>) and a plurality of N-type thermoelectric (<NUM>) legs alternately disposed on the first substrate (<NUM>);
a second substrate disposed on the plurality of P-type thermoelectric legs (<NUM>) and the plurality of N-type thermoelectric legs (<NUM>);
a plurality of first electrodes (<NUM>) disposed between the first substrate (<NUM>) and the plurality of P-type thermoelectric legs (<NUM>) and the plurality of N-type thermoelectric legs (<NUM>) and respectively having a pair of P-type thermoelectric leg (<NUM>) and N-type thermoelectric leg (<NUM>) disposed therein; and
a plurality of second electrodes (<NUM>) disposed between the second substrate and the plurality of P-type thermoelectric legs (<NUM>) and the plurality of N-type thermoelectric legs (<NUM>) and respectively having a pair of P-type thermoelectric leg (<NUM>) and N-type thermoelectric leg (<NUM>) disposed therein,
wherein a pair of P-type solder layer (<NUM>) and N-type solder layer (<NUM>) and a barrier layer (<NUM>) disposed between the pair of P-type solder layer (<NUM>) and N-type solder layer (<NUM>) are disposed on each of the plurality of first electrodes (<NUM>),
a pair of P-type solder layer (<NUM>) and N-type solder layer (<NUM>) and a barrier layer (<NUM>) disposed between the pair of P-type solder layer (<NUM>) and N-type solder layer (<NUM>) are disposed on each of the plurality of second electrodes (<NUM>),
each of the P-type thermoelectric legs (<NUM>) directly comes into contact with each of the P-type solder layers (<NUM>), and
each of the N-type thermoelectric legs (<NUM>) directly comes into contact with each of the N-type solder layers (<NUM>),
characterized in that
a melting point of the barrier layer (<NUM>) is greater than a melting point of each of the pair of P-type solder layer (<NUM>) and N-type solder layer (<NUM>),
that each of the barrier layers (<NUM>) has an insulation property, and
that an adhesive resin layer (<NUM>) is further provided between the first substrate (<NUM>) and the plurality of first electrodes (<NUM>).