KR102366388B1 - Thermo electric element - Google Patents

Abstract

A thermoelectric element according to an embodiment of the present invention includes a first substrate, a plurality of P-type thermoelectric legs and a plurality of N-type thermoelectric legs alternately disposed on the first substrate, the plurality of P-type thermoelectric legs, and the plurality of A second substrate disposed on the N-type thermoelectric leg, the plurality of P-type thermoelectric legs, a plurality of electrodes connecting the plurality of N-type thermoelectric legs in series, and a dummy pad disposed between the plurality of electrodes.

Description

Thermoelectric element {THERMO ELECTRIC ELEMENT}

The present invention relates to a thermoelectric device.

The thermoelectric phenomenon is a phenomenon that occurs by the movement of electrons and holes inside a material, and refers to direct energy conversion between heat and electricity.

Thermoelectric element is a generic term for elements using thermoelectric phenomenon, elements using temperature change of electrical resistance, element using Seebeck effect, a phenomenon in which electromotive force is generated by temperature difference, and Peltier effect, which is a phenomenon in which heat absorption or heat is generated by current There are devices using .

Thermoelectric elements are being applied in various ways to home appliances, electronic parts, communication parts, and the like, and the demand for thermoelectric performance of thermoelectric elements is increasing.

A thermoelectric element includes a substrate, an electrode, and a thermoelectric leg. A plurality of electrodes are disposed adjacent to each other on the substrate, and a P-type thermoelectric leg and an N-type thermoelectric leg are disposed on each electrode.

Meanwhile, when a voltage is applied to the thermoelectric element under a high temperature and high humidity environment, a phenomenon in which one electrode migrates to another adjacent electrode may occur. In this case, a circuit constituting the thermoelectric element may be shorted.

An object of the present invention is to provide a thermoelectric device having excellent thermoelectric performance and reliability.

A thermoelectric element according to an embodiment of the present invention includes a first substrate, a plurality of P-type thermoelectric legs and a plurality of N-type thermoelectric legs alternately disposed on the first substrate, the plurality of P-type thermoelectric legs, and the plurality of A second substrate disposed on the N-type thermoelectric leg, the plurality of P-type thermoelectric legs, a plurality of electrodes connecting the plurality of N-type thermoelectric legs in series, and a dummy pad disposed between the plurality of electrodes.

The plurality of electrodes may include 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 the second substrate and the plurality of P-type thermoelectric legs; a plurality of second electrodes disposed between the plurality of N-type thermoelectric legs, wherein the dummy pad is disposed between the plurality of first electrodes on the first substrate or the plurality of second electrodes on the second substrate It may be disposed between the electrodes.

The dummy pad may be disposed to be spaced apart from the plurality of first electrodes between the plurality of first electrodes, or disposed to be spaced apart from the plurality of second electrodes between the plurality of second electrodes.

The dummy pad may include Cu.

The dummy pad may further include at least one of silver (Ag), gold (Au), and platinum (Pt).

The P-type thermoelectric leg and the N-type thermoelectric leg may not be disposed on the dummy pad.

According to an embodiment of the present invention, a thermoelectric device having excellent thermoelectric performance and reliability may be obtained. In particular, even if migration of the electrode occurs under a high temperature or high humidity environment, it is possible to obtain a structure in which a short circuit of a circuit constituting the thermoelectric element is prevented.

1 is a cross-sectional view of a thermoelectric element, and FIG. 2 is a perspective view of the thermoelectric element.
3 is a diagram for describing a relationship between an electrode and a thermoelectric leg in detail.
4 to 5 are diagrams showing the migration phenomenon of the electrode.
6 is a thermoelectric device according to an embodiment of the present invention.
7 is a thermoelectric device according to another embodiment of the present invention.
8 to 10 are thermoelectric devices according to still another embodiment of the present invention.

Since the present invention may have various changes and may have various embodiments, specific embodiments will be illustrated and described in the drawings. However, this is not intended to limit the present invention to specific embodiments, and it should be understood to include all modifications, equivalents and substitutes included in the spirit and scope of the present invention.

Terms including an ordinal number such as second, first, etc. may be used to describe various elements, but the elements are not limited by the terms. The above terms are used only for the purpose of distinguishing one component from another. For example, without departing from the scope of the present invention, the second component may be referred to as the first component, and similarly, the first component may also be referred to as the second component. and/or includes a combination of a plurality of related listed items or any of a plurality of related listed items.

When a component is referred to as being “connected” or “connected” to another component, it may be directly connected or connected to the other component, but it is understood that other components may exist in between. it should be On the other hand, when it is said that a certain element is "directly connected" or "directly connected" to another element, it should be understood that the other element does not exist in the middle.

The terms used in the present application are only used to describe specific embodiments, and are not intended to limit the present invention. The singular expression includes the plural expression unless the context clearly dictates otherwise. In the present application, terms such as “comprise” or “have” are intended to designate that a feature, number, step, operation, component, part, or combination thereof described in the specification exists, but one or more other features It should be understood that this does not preclude the existence or addition of numbers, steps, operations, components, parts, or combinations thereof.

Unless defined otherwise, all terms used herein, including technical or scientific terms, have the same meaning as commonly understood by one of ordinary skill in the art to which this invention belongs. Terms such as those defined in commonly used dictionaries should be interpreted as having a meaning consistent with the meaning in the context of the related art, and should not be interpreted in an ideal or excessively formal meaning unless explicitly defined in the present application. does not

Hereinafter, the embodiment will be described in detail with reference to the accompanying drawings, but the same or corresponding components are given the same reference numerals regardless of reference numerals, and overlapping descriptions thereof will be omitted.

1 is a cross-sectional view of a thermoelectric element, and FIG. 2 is a perspective view of the thermoelectric element.

1 to 2 , the thermoelectric element 100 includes a lower substrate 110 , a lower electrode 120 , a P-type thermoelectric leg 130 , an N-type thermoelectric leg 140 , an upper electrode 150 , and an upper substrate. (160).

The lower electrode 120 is disposed between the lower substrate 110 and the lower bottom surfaces of the P-type thermoelectric leg 130 and the N-type thermoelectric leg 140 , and the upper electrode 150 is formed between the upper substrate 160 and the P-type thermoelectric leg 140 . It is disposed between the thermoelectric leg 130 and the upper bottom surface of the N-type thermoelectric leg 140 . Accordingly, the plurality of P-type thermoelectric legs 130 and the plurality of N-type thermoelectric legs 140 are electrically connected by the lower electrode 120 and the upper electrode 150 .

For example, when a voltage is applied to the lower electrode 120 and the upper electrode 150 through a lead wire, the substrate through which current flows from the P-type thermoelectric leg 130 to the N-type thermoelectric leg 140 due to the Peltier effect is heated. The substrate in which current flows from the N-type thermoelectric leg 140 to the P-type thermoelectric leg 130 may be heated to act as a heat generating part.

Here, the P-type thermoelectric leg 130 and the N-type thermoelectric leg 140 may be bismuth telluride (Bi-Te)-based thermoelectric legs including bismuth (Bi) and tellurium (Ti) as main raw materials. P-type thermoelectric leg 130 is antimony (Sb), nickel (Ni), aluminum (Al), copper (Cu), silver (Ag), lead (Pb), boron (B), gallium (Ga), tellurium It may be a bismuthtelluride (Bi-Te)-based thermoelectric leg including at least one of (Te), bismuth (Bi), and indium (In). N-type thermoelectric leg 140 is selenium (Se), nickel (Ni), aluminum (Al), copper (Cu), silver (Ag), lead (Pb), boron (B), gallium (Ga), tellurium It may be a bismuthtelluride (Bi-Te)-based thermoelectric leg including at least one of (Te), bismuth (Bi), and indium (In).

The P-type thermoelectric leg 130 and the N-type thermoelectric leg 140 may be formed in a bulk type or a stack type. In general, the bulk-type P-type thermoelectric leg 130 or the bulk-type N-type thermoelectric leg 140 heat-treats a thermoelectric material to manufacture an ingot, grinds the ingot and sieves to obtain a powder for the thermoelectric leg, and then It can be obtained through the process of sintering and cutting the sintered body. The laminated type P-type thermoelectric leg 130 or the laminated type N-type thermoelectric leg 140 is formed by applying a paste containing a thermoelectric material on a sheet-shaped substrate to form a unit member, then stacking the unit member and cutting the unit through the process. can be obtained

The performance of the thermoelectric element according to an embodiment of the present invention may be expressed as a Seebeck index. The Seebeck index (ZT) can be expressed as in Equation (1).

Here, α is the Seebeck coefficient [V/K], σ is the electrical conductivity [S/m], and α ² σ is the power factor (Power Factor, [W/mK ² ]). And, T is the temperature, k is the thermal conductivity [W/mK]. k can be expressed as a·c _p ·ρ, a is the thermal diffusivity [cm ² /S], c _p is the specific heat [J/gK], ρ is the density [g/cm ³ ].

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

3 is a diagram for describing a relationship between an electrode and a thermoelectric leg in detail.

Referring to FIG. 3 , an N-type thermoelectric leg 140-1 and a P-type thermoelectric leg 130-1 are disposed on the lower electrode 120-1. In addition, a P-type thermoelectric leg 130-1 and an N-type thermoelectric leg 140-2 are disposed under the upper electrode 150-1. In addition, an N-type thermoelectric leg 140-2 and a P-type thermoelectric leg 130-2 are disposed on the lower electrode 120-2. In addition, a P-type thermoelectric leg 130-2 and an N-type thermoelectric leg 140-3 are disposed under the upper electrode 150-2. In this way, the plurality of P-type thermoelectric legs 130 and the plurality of N-type thermoelectric legs 140 may be electrically connected in series through the lower electrode 120 and the upper electrode 150 .

Meanwhile, as illustrated in FIGS. 4 to 5 , when a voltage is applied to the thermoelectric element under a high temperature or high humidity environment, an electrode migration phenomenon may occur. For example, when the lower electrode 120 - 2 grows toward the adjacent lower electrode 120 - 5 , the thermoelectric element is caused by the contact between the lower electrode 120 - 2 and the lower electrode 120 - 5 . The circuit of (100) may be shorted.

According to an embodiment of the present invention, a dummy pad is disposed between the electrodes to prevent a short circuit due to migration of the electrodes.

6 is a thermoelectric device according to an embodiment of the present invention. For convenience of description, only the lower substrate, the lower electrode, and the thermoelectric leg are illustrated and described, but the same structure may be applied to the upper substrate and the upper electrode.

Referring to FIG. 6 , a plurality of lower electrodes 120 are disposed on the lower substrate 110 , and a P-type thermoelectric leg and an N-type thermoelectric leg are disposed on each lower electrode 120 . The plurality of P-type thermoelectric legs and the plurality of N-type thermoelectric legs are connected in series through the plurality of lower electrodes 120 and the plurality of upper electrodes, through which current may flow.

In addition, a dummy pad 170 is disposed between the plurality of lower electrodes 120 on the lower substrate 110 . In addition, the P-type thermoelectric leg and the N-type thermoelectric leg are not disposed on the dummy pad 170 . Accordingly, even when a voltage is applied to the thermoelectric element, no current flows through the dummy pad 170 .

As such, even if a voltage is applied to the thermoelectric element under a high temperature or high humidity environment to cause migration of the lower electrode 120 - 2 , it does not come into contact with the adjacent lower electrode 120 - 5 , so the circuit of the thermoelectric element 100 is not in contact. Short circuit can be prevented.

In this case, the dummy pad 170 may include the same material as the lower electrode 120 . For example, when the lower electrode 120 is made of copper (Cu), the dummy pad 170 may also be made of Cu.

Alternatively, when the lower electrode 120 is made of Cu, the dummy pad 170 may further include at least one of silver (Ag), gold (Au), and platinum (Pt) as well as Cu. Silver (Ag), gold (Au), and platinum (Pt) are materials with excellent cohesion with Cu. Accordingly, when a voltage is applied to the thermoelectric element under a high temperature or high humidity environment, the lower electrode 120 grows in the direction of the dummy pad 170 . As described above, since the dummy pad 170 blocks the growth path of one lower electrode 120 - 2 to the adjacent lower electrode 120 - 5 , a short circuit in the thermoelectric element 100 can be prevented. .

In this case, the dummy pad 170 may be disposed between the plurality of lower electrodes 120 to be spaced apart from the plurality of lower electrodes 120 . For example, when the width of the dummy pad 170 is 100, the separation distance between the dummy pad 170 and the lower electrode 120 may be 1 to 10. When the distance between the dummy pad 170 and the lower electrode 120 is within the above range, the dummy pad 170 grows into the dummy pad 170 during migration of the lower electrode 120, and a growth path toward the adjacent lower electrode 120 is taken. easy to block

Meanwhile, although it is illustrated in FIG. 6 that the distance between the dummy pad 170 and the lower electrodes 120 - 2 and 120 - 5 is the same, the present invention is not limited thereto.

As shown in FIG. 7 , the spacing between the lower electrodes 120-1, 120-2, and 120-3 in one row and the dummy pad 170 is equal to the lower electrode 120-4, 120-5, and 120-5 in the other adjacent row. 120 - 6 ) and the dummy pad 170 may be formed to be narrower than the gap. Accordingly, it is possible to reduce the possibility that both lower electrodes 120 - 2 and 120 - 5 simultaneously contact the same dummy pad 170 .

Meanwhile, although it is illustrated that the length of the electrode and the length of the dummy pad are the same in FIGS. 6 to 7 , the present invention is not limited thereto. The shape of the dummy pad may be variously modified.

8 to 10 show a thermoelectric device according to still another embodiment of the present invention.

8 to 10 , a plurality of lower electrodes 120 are disposed on the lower substrate 110 , and a P-type thermoelectric leg and an N-type thermoelectric leg are disposed on each lower electrode 120 . The plurality of P-type thermoelectric legs and the plurality of N-type thermoelectric legs are connected in series through the plurality of lower electrodes 120 and the plurality of upper electrodes, through which current may flow.

In addition, a dummy pad 170 is disposed between the plurality of lower electrodes 120 on the lower substrate 110 . In addition, the P-type thermoelectric leg and the N-type thermoelectric leg are not disposed on the dummy pad 170 . Accordingly, even when a voltage is applied to the thermoelectric element, no current flows through the dummy pad 170 .

As illustrated in FIG. 8 , the dummy pad 170 may be disposed to correspond to a column formed by the plurality of lower electrodes 120 - 1 , 120 - 2 , and 120 - 3 . Accordingly, since the process for forming the dummy pad 170 is simple, manufacturing cost is low.

Alternatively, as illustrated in FIG. 9 , the dummy pad 170 may be disposed to have a size smaller than that of one lower electrode 120 - 1 . Accordingly, the possibility that both lower electrodes contact one dummy pad at the same time may be reduced.

Alternatively, as illustrated in FIG. 10 , the dummy pad structures of FIGS. 8 and 9 may be mixed and disposed.

Although the above has been described with reference to the preferred embodiment of the present invention, those skilled in the art can variously modify and change the present invention within the scope without departing from the spirit and scope of the present invention as described in the claims below. You will understand that it can be done.

120: lower electrode
130: P-type thermoelectric leg
140: N-type thermoelectric leg
170: dummy pad

Claims (6)

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 electrodes connecting the plurality of P-type thermoelectric legs and the plurality of N-type thermoelectric legs in series; and
a dummy pad disposed between the plurality of electrodes;
The plurality of electrodes,
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
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;
the dummy pad is disposed between a first column electrode and a second column electrode among the plurality of first electrodes on the first substrate;
A distance between the first column electrode and the dummy pad and a distance between the second column electrode and the dummy pad are 1 to 10% of a width of the dummy pad, respectively;
A distance between the first column electrode and the dummy pad is different from a distance between the second column electrode and the dummy pad. According to claim 1,
The dummy pad is further disposed between the plurality of second electrodes on the second substrate. delete According to claim 1,
The dummy pad is a thermoelectric element including Cu. 5. The method of claim 4,
The dummy pad further includes at least one of silver (Ag), gold (Au), and platinum (Pt). 5. The method of claim 4,
A thermoelectric device in which the P-type thermoelectric leg and the N-type thermoelectric leg are not disposed on the dummy pad.

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