thermoelectric element

Abstract

A thermoelectric element is provided according to an embodiment, including: a first insulating portion; a plurality of first electrodes provided on the first insulating portion; a second electrode provided above the first electrodes; a first conductive semiconductor structure and a second conductive semiconductor structure provided between the first electrodes and the second electrode spaced apart from each other; and a second insulating portion provided on the second electrode, wherein the first insulating portion includes a first protruding portion protruding toward the first electrodes, and the second insulating portion includes a second protruding portion protruding toward the second electrode.

Description

Technical Field

[0001] This invention relates to thermoelectric elements, and more particularly to the structure of electrodes disposed on a substrate. Background Technology

[0002] The thermoelectric effect is a direct energy conversion between heat and electricity that occurs due to the movement of electrons and holes in a material.

[0003] Thermoelectric elements are often referred to as elements that utilize the thermoelectric effect and have a structure in which P-type thermoelectric materials and N-type thermoelectric materials are disposed between and bonded to the metal electrodes to form a PN junction pair.

[0004] Thermoelectric elements can be classified into elements that utilize resistance changes that depend on temperature, elements that utilize the Seebeck effect in which an electromotive force is generated due to a temperature difference, and elements that utilize the Peltier effect in which heat absorption or heating occurs due to current, etc.

[0005] Thermoelectric elements have been widely used in household appliances, electronic components, and communication devices. For example, they can be used in cooling devices, heating devices, and power generation devices. Therefore, the demand for the thermoelectric performance of thermoelectric elements is gradually increasing.

[0006] In this case, the thermoelectric element has the problem of dielectric breakdown between the electrode and the substrate. Summary of the Invention

[0007] Technical issues

[0008] The present invention aims to provide a structure for electrodes of thermoelectric elements for improving reliability.

[0009] Technical solutions

[0010] One aspect of the present invention provides a thermoelectric element comprising: a first insulating portion; a plurality of first electrodes disposed on the first insulating portion; a second electrode disposed above the first electrodes; a first conductive semiconductor structure and a second conductive semiconductor structure disposed spaced apart from each other between the first electrodes and the second electrodes; and a second insulating portion disposed on the second electrodes, wherein the first insulating portion includes a first protrusion protruding toward the first electrodes, and the second insulating portion includes a second protrusion protruding toward the second electrodes.

[0011] The first and second protrusions may overlap in the vertical direction.

[0012] Based on the first conductive semiconductor structure and the second conductive semiconductor structure, the first protrusion and the second protrusion can have the same shape.

[0013] Based on the first conductive semiconductor structure and the second conductive semiconductor structure, the first protrusion and the second protrusion can have different shapes.

[0014] The first protrusion and the second protrusion can be arranged at intervals from each other in the vertical direction.

[0015] The height of the first protrusion can be less than or equal to 0.5 times the thickness of the first electrode.

[0016] The height of the first protrusion can be greater than or equal to 0.5 times the thickness of the first electrode.

[0017] Each of the first electrode and the second electrode may include a recessed portion disposed at an edge of a surface facing the adjacent substrate; and the recessed portion may have a closed loop when viewed from above.

[0018] Each of the first protrusion and the second protrusion can be disposed in the groove portion.

[0019] Each of the first electrode and the second electrode may further include a protruding electrode disposed at the edge of the lower surface of the groove portion; and the height of the protrusion in the vertical direction may be less than or equal to the height of the groove portion in the vertical direction.

[0020] Beneficial effects

[0021] According to embodiments of the present invention, thermoelectric elements with high electrical reliability can be obtained.

[0022] Specifically, according to embodiments of the present invention, a thermoelectric element comprising a groove formed along an edge of a surface disposed toward a substrate adjacent to an electrode can be provided.

[0023] Furthermore, the thermoelectric element according to the embodiments of the present invention can be applied not only to small-scale applications but also to large-scale applications, such as vehicles, ships, steel mills, and incinerators. Attached Figure Description

[0024] Figure 1 This is a perspective view showing a thermoelectric element according to an embodiment of the present invention.

[0025] Figure 2 This is a cross-sectional view showing a thermoelectric element according to an embodiment of the present invention.

[0026] Figure 3 This is a perspective view showing an electrode according to a first embodiment of the present invention.

[0027] Figure 4 This is a top view showing the electrode according to a first embodiment of the present invention.

[0028] Figure 5 This is a side view showing an electrode according to a first embodiment of the present invention.

[0029] Figure 6 This is a bottom view showing the electrode according to a first embodiment of the present invention.

[0030] Figure 7 This is a perspective view showing the electrode and the first protrusion according to a first embodiment of the present invention.

[0031] Figure 8 This is a cross-sectional view showing the electrode and the first protrusion according to a first embodiment of the present invention.

[0032] Figure 9 This is a cross-sectional view showing a thermoelectric element according to a second embodiment of the present invention.

[0033] Figure 10 It is shown Figure 9 A magnified view of part K1.

[0034] Figure 11 It is shown Figure 10 A view of the modified implementation method.

[0035] Figure 12 This is a cross-sectional view showing a thermoelectric element according to a third embodiment of the present invention.

[0036] Figure 13 It is shown Figure 12 A magnified view of part of K2.

[0037] Figure 14 It is shown Figure 13 The diagram shows the modified implementation method.

[0038] Figure 15 This is a side view showing the electrode and the first protrusion according to another modified embodiment.

[0039] Figures 16a to 16e This is a diagram used to describe a method for manufacturing an electrode according to the first embodiment. Detailed Implementation

[0040] In the following, exemplary embodiments of the present invention will be described in detail with reference to the accompanying drawings.

[0041] However, the spirit of the present invention is not limited to the embodiments described, and can be implemented using various other embodiments. Furthermore, at least one component of an embodiment can be selectively coupled, replaced, and used within the scope of the spirit of the present invention.

[0042] Furthermore, unless otherwise explicitly and specifically defined by the context, all terms used herein (including technical and scientific terms) may be interpreted as having the meaning commonly understood by those skilled in the art, and the meaning of commonly used terms, for example, as defined in commonly used dictionaries, will be interpreted by taking into account the contextual meaning of the relevant art.

[0043] Furthermore, the terminology used in the embodiments of the present invention is considered in a descriptive sense and is not intended to limit the present invention.

[0044] In this specification, unless the context specifically indicates otherwise, the singular form may include its plural form, and in the case of describing “at least one (or one or more) of A, B and C”, this may include at least one combination of all possible combinations of A, B and C.

[0045] In addition, in the description of the components of the present invention, terms such as "first", "second", "A", "B", "(a)" and "(b)" may be used.

[0046] These terms are used only to distinguish one element from another, and the nature, order, etc., of the elements are not limited by these terms.

[0047] In addition, when an element is referred to as being “connected” or “coupled” to another element, such a description may include not only cases where the element is directly connected to or coupled to another element, but also cases where the element is connected to or coupled to another element and another element is disposed therebetween.

[0048] Furthermore, when any element is described as being formed or disposed "above" or "below" another element, such a description includes not only cases where the two elements are formed or disposed in direct contact with each other, but also cases where one or more other elements are formed or disposed between the two elements. Additionally, when an element is described as being disposed "above or below" another element, such a description can include cases where one element is disposed on the upper or lower side relative to the other element.

[0049] Figure 1 This is a perspective view showing a thermoelectric element according to an embodiment of the present invention, and Figure 2 This is a cross-sectional view showing a thermoelectric element according to an embodiment of the present invention.

[0050] Reference Figure 1 and Figure 2 The thermoelectric element 100 includes a lower substrate 110, a lower electrode 120, a second conductive semiconductor structure 130, a first conductive semiconductor structure 140, an upper electrode 150, and an upper substrate 160.

[0051] A lower electrode 120 is disposed between the lower substrate 110 and the lower surfaces of the second conductive semiconductor structure 130 and the first conductive semiconductor structure 140, and an upper electrode 150 is disposed between the upper substrate 160 and the upper surfaces of the second conductive semiconductor structure 130 and the first conductive semiconductor structure 140. Therefore, a plurality of second conductive semiconductor structures 130 and a plurality of first conductive semiconductor structures 140 are electrically connected via the lower electrode 120 and the upper electrode 150. Pairs of second conductive semiconductor structures 130 and first conductive semiconductor structures 140 disposed between and electrically connected to the lower electrode 120 and the upper electrode 150 can form a unit cell. In this specification, the lower electrode 120 can be used interchangeably with "first electrode." Additionally, in this specification, the lower electrode 120 can be used interchangeably with "second electrode." Furthermore, the term "electrode" has the meaning of including all upper and lower electrodes. Additionally, the lower substrate can be used interchangeably with "first substrate," and the upper substrate can be used interchangeably with "second substrate." Additionally, in this specification, the first direction (X-axis direction) may include a direction X1 from the first substrate toward the second substrate and a direction X2 opposite to direction X1, and may be used as a "vertical direction". Furthermore, the first electrode and the second electrode may be configured as multiple first electrodes and multiple second electrodes.

[0052] For example, when a voltage is applied to the lower electrode 120 and the upper electrode 150 via leads 181 and 182, due to the Peltier effect, current flowing through the substrate of the second conductive semiconductor structure 130 to the first conductive semiconductor structure 140 can absorb heat to serve as a cooling component, and current flowing through the substrate of the first conductive semiconductor structure 140 to the second conductive semiconductor structure 130 can be heated to serve as a heating component. Alternatively, when different temperatures are applied to the lower electrode 120 and the upper electrode 150, due to the Seebeck effect, charge can move through the second conductive semiconductor structure 130 and the first conductive semiconductor structure 140, thereby also generating electricity.

[0053] In this configuration, each of the second conductive semiconductor structure 130 and the first conductive semiconductor structure 140 may be a Bi-Te-based thermoelectric leg primarily comprising bismuth (Bi) and tellurium (Te). The second conductive semiconductor structure 130 may be a Bi-Te-based thermoelectric leg comprising at least one of antimony (Sb), nickel (Ni), aluminum (Al), copper (Cu), silver (Ag), lead (Pb), boron (B), gallium (Ga), tellurium (Te), bismuth (Bi), and indium (In). As an example, based on a total weight of 100 wt%, the second conductive semiconductor structure 130 may comprise 99 wt% to 99.999 wt% Bi-Sb-Te as the main material and 0.001 wt% to 1 wt% of at least one of nickel (Ni), aluminum (Al), copper (Cu), silver (Ag), lead (Pb), boron (B), gallium (Ga), and indium (In). The first conductive semiconductor structure 140 may be a Bi-Te-based thermoelectric arm comprising at least one of selenium (Se), nickel (Ni), aluminum (Al), copper (Cu), silver (Ag), lead (Pb), boron (B), gallium (Ga), tellurium (Te), bismuth (Bi), and indium (In). As an example, based on 100 wt% of total weight, the first conductive semiconductor structure 140 may comprise 99 wt% to 99.999 wt% of Bi-Se-Te as the main material and 0.001 wt% to 1 wt% of at least one of nickel (Ni), aluminum (Al), copper (Cu), silver (Ag), lead (Pb), boron (B), gallium (Ga), and indium (In).

[0054] Each of the second conductive semiconductor structure 130 and the first conductive semiconductor structure 140 can be formed as a bulk type or a stacked type. Typically, the bulk type second conductive semiconductor structure 130 or the bulk type first conductive semiconductor structure 140 can be formed by a process in which the thermoelectric material is heat-treated to produce an ingot, the ingot is ground and strained to obtain powder for a thermoelectric arm, the powder is sintered, and the sintered powder is cut. In this case, each of the second conductive semiconductor structure 130 and the first conductive semiconductor structure 140 can be a polycrystalline thermoelectric arm. As described above, when each of the second conductive semiconductor structure 130 and the first conductive semiconductor structure 140 is a polycrystalline thermoelectric arm, the strength of each of the second conductive semiconductor structure 130 and the first conductive semiconductor structure 140 can be increased. The stacked second conductive semiconductor structure 130 or the stacked first conductive semiconductor structure 140 can be formed by a process in which a paste containing thermoelectric material is applied to respective sheet-shaped substrate members to form unit members, and the unit members are stacked and cut.

[0055] In this case, the paired second conductive semiconductor structure 130 and the first conductive semiconductor structure 140 may have the same shape and volume, or they may have different shapes and volumes. As an example, since the second conductive semiconductor structure 130 and the first conductive semiconductor structure 140 have different conductivity characteristics, the height or cross-sectional area of ​​the first conductive semiconductor structure 140 may be different from that of the second conductive semiconductor structure 130.

[0056] In this case, the second conductive semiconductor structure 130 or the first conductive semiconductor structure 140 may have a cylindrical shape, a polygonal prism shape, an elliptical prism shape, etc.

[0057] The performance of a thermoelectric element according to one embodiment of the present invention can be expressed as a thermoelectric performance quality factor (ZT). The thermoelectric performance quality factor (ZT) can be expressed by Equation 1.

[0058] [Equation 1]

[0059] ZT=α 2 ·σ·T / k

[0060] Here, α represents the Seebeck coefficient [V / K], σ represents the conductivity [S / m], and α 2 σ represents the power factor [W / mK] 2 Additionally, T represents temperature, and k represents thermal conductivity [W / mK]. k can be expressed as a·cp·ρ, where a represents thermal diffusivity [cm]. 2 / s], cp represents specific heat [J / gK], and ρ represents density [g / cm³]. 3 ].

[0061] To obtain the thermoelectric performance quality factor (ZT) of a thermoelectric element, the Z value (V / K) is measured using a Z meter, and the measured Z value can be used to calculate the thermoelectric performance quality factor (ZT).

[0062] In this configuration, each of the lower electrode 120 disposed between the lower substrate 110 and the second conductive semiconductor structure 130 and the first conductive semiconductor structure 140, and the upper electrode 150 disposed between the upper substrate 160 and the second conductive semiconductor structure 130 and the first conductive semiconductor structure 140, may include at least one of copper (Cu), silver (Ag), aluminum (Al), and nickel (Ni), and may have a thickness of 0.01 mm to 0.3 mm. When the thickness of the lower electrode 120 or the upper electrode 150 is less than 0.01 mm, the electrode function is reduced, and therefore the conductivity may be reduced. Conversely, when the thickness of the lower electrode 120 or the upper electrode 150 is greater than 0.3 mm, the resistance increases, and therefore the conduction efficiency may be reduced.

[0063] Furthermore, the lower substrate 110 and the upper substrate 160, which are opposite each other, can be metal substrates, and the thickness of each of the lower substrate 110 and the upper substrate 160 can be in the range of 0.1 mm to 1.5 mm. When the thickness of the metal substrate is less than 0.1 mm or greater than 1.5 mm, the reliability of the thermoelectric element may be reduced because the thermal radiation properties or thermal conductivity may become too high.

[0064] In addition, when the lower substrate 110 and the upper substrate 160 are metal substrates, the first insulating portion 170a and the second insulating portion 170b can be further formed between the lower substrate 110 and the lower electrode 120 and between the upper substrate 160 and the upper electrode 150.

[0065] Therefore, the thermoelectric element 100 according to this embodiment may further include an insulating portion 170, which includes a first insulating portion 170a and a second insulating portion 170b.

[0066] First, each of the first insulating portion 170a and the second insulating portion 170b may include a material having a thermal conductivity of 1 W / mK to 20 W / mK. In this case, each of the first insulating portion 170a and the second insulating portion 170b may be a resin composition comprising at least one of epoxy resin and silicone resin and an inorganic material, a layer formed of a silicon composite comprising silicon and an inorganic material, or an alumina layer. In this case, the inorganic material may be at least one of oxides, carbides, and nitrides comprising aluminum, boron, silicon, etc.

[0067] Additionally, the insulating portion 170 may be disposed between adjacent lower electrodes 120 or adjacent upper electrodes 150, and located closer to the second conductive semiconductor structure 130 or the first conductive semiconductor structure 140 than the protrusion 180, which will be described below. For example, the length of the insulating portion 170 in the first direction (X-axis direction) may be greater than the length of the protrusion 180 in the first direction.

[0068] Additionally, the insulating portion 170 may protrude toward adjacent substrates between adjacent lower electrodes 120 or adjacent upper electrodes 150. For example, the upper surface of the first insulating portion 170a may be located above the upper surface of the first protrusion 180a and may protrude toward the lower substrate 110 between adjacent lower electrodes 120. Alternatively, the upper surface of the first insulating portion 170a may be recessed toward the upper substrate 160. Such descriptions can be applied equivalently to the various embodiments described below.

[0069] In this case, the dimensions of the lower substrate 110 and the upper substrate 160 can also be different. That is, the volume, thickness, or area of ​​one of the lower substrate 110 and the upper substrate 160 can be larger than the volume, thickness, or area of ​​the other. In this case, the thickness can be the thickness in the direction from the lower substrate 110 toward the upper substrate 160, and the area can be the area in the direction perpendicular to the direction from the substrate 110 toward the upper substrate 160. Therefore, the heat absorption or radiation performance of the thermoelectric element can be improved. Preferably, at least one of the volume, thickness, and area of ​​the lower substrate 110 can be larger than that of the upper substrate 160. In this case, when the lower substrate 110 is disposed in a high-temperature region for the Seebeck effect or used as a heating region for the Peltier effect, or when a sealing member for protecting the thermoelectric element (described below) from the influence of the external environment is disposed on the lower substrate 110, at least one of the volume, thickness, and area of ​​the lower substrate 110 can be larger than that of the upper substrate 160. In this case, the area of ​​the lower substrate 110 can be formed in the range of 1.2 to 5 times the area of ​​the upper substrate 160. When the area of ​​the current substrate 110 is less than 1.2 times the area of ​​the upper substrate 160, the increase in heat transfer efficiency may be minimal. However, when the area of ​​the current substrate 110 is more than 5 times the area of ​​the upper substrate 160, the heat transfer efficiency may decrease significantly, and the basic shape of the thermoelectric device may not be maintained.

[0070] Additionally, a thermal radiation pattern, such as a non-uniform pattern, can be formed on the surface of at least one of the lower substrate 110 and the upper substrate 160. Therefore, the thermal radiation performance of the thermoelectric element can be improved. When a non-uniform pattern is formed on the surface in contact with the second conductive semiconductor structure 130 or the first conductive semiconductor structure 140, the bonding properties between the thermoelectric arm and the substrate can be improved. The thermoelectric element 100 includes a lower substrate 110, a lower electrode 120, a second conductive semiconductor structure 130, a first conductive semiconductor structure 140, an upper electrode 150, and an upper substrate 160.

[0071] Although not shown in the accompanying drawings, a sealing member may be further disposed between the lower substrate 110 and the upper substrate 160. The sealing member may be disposed on the side surfaces of the lower electrode 120, the second conductive semiconductor structure 130, the first conductive semiconductor structure 140, and the upper electrode 150 between the lower substrate 110 and the upper substrate 160. Therefore, the lower electrode 120, the second conductive semiconductor structure 130, the first conductive semiconductor structure 140, and the upper electrode 150 can be sealed to prevent the influence of external moisture, heat, contamination, etc.

[0072] Furthermore, in the thermoelectric element according to this embodiment, the first insulating portion 170a and the second insulating portion 170b may also include a first protrusion 180a and a second protrusion 180b. The first protrusion 180a and the second protrusion 180b may be disposed in the recessed portions of the lower electrode 120 and the upper electrode 150, which will be described below. For example, the first protrusion 180a and the second protrusion 180b may include a first protrusion 180a disposed in the recessed portion of the lower electrode 120 and a second protrusion 180b disposed in the recessed portion of the upper electrode 150. Due to this configuration, the problem of dielectric breakdown and electrical connection between the lower electrode 120 and the upper electrode 150 and the lower substrate 110 and the upper substrate 160 caused by the lower electrode 120 and the upper electrode 150 passing through the first insulating portion 170a and the second insulating portion 170b can be prevented. This will be described below. In this specification, the first protrusion 180a will be described primarily, which is equivalent to the second protrusion 180b, and the insulating portion 170 may or may not include the first protrusion 180a and the second protrusion 180b as elements. That is, the first insulating portion 170a may be formed of a material different from that of the first protrusion 180a. Alternatively, the first insulating portion 170a may be formed of the same material as the first protrusion 180a. Therefore, it should be understood that the first insulating portion 170a may or may not have a boundary surface between the first insulating portion 170a and the first protrusion 180a. Thus, the protrusion will be described as an element included in the insulating portion or as an element different from the insulating portion.

[0073] Figure 3 This is a perspective view showing the electrode according to a first embodiment of the present invention. Figure 4 This is a top view showing the electrode according to a first embodiment of the present invention. Figure 5 This is a side view showing the electrode according to a first embodiment of the present invention, and Figure 6 This is a bottom view showing the electrode according to a first embodiment of the present invention.

[0074] Reference Figures 3 to 6 The electrode 120 or 150 according to the first embodiment includes a first electrode 120 or a second electrode 150, and the first electrode 120 will be mainly described below.

[0075] The first electrode 120 may include a first surface S1, a second surface S2, and a third surface S3.

[0076] The first surface S1 may be a surface disposed on one side of a substrate (e.g., lower substrate 110) adjacent to the first electrode 120. At least a portion of the first surface S1 may be adjacent to the substrate 110 or the first insulating portion 170a on the substrate 110 (see [link to relevant documentation]). Figure 2 Contact. The first surface S1 can be rectangular, but it can also be polygonal or circular.

[0077] Additionally, the first surface S1 may include a first edge portion E1, a second edge portion E2, a third edge portion E3, and a fourth edge portion E4 as the outermost portion.

[0078] The first edge portion E1 can be configured to face the second edge portion E2. Additionally, the third edge portion E3 can be configured to face the fourth edge portion E4. Furthermore, the third edge portion E3 and the fourth edge portion E4 can be located between the first edge portion E1 and the second edge portion E2.

[0079] Furthermore, the lengths of the first edge portion E1 and the second edge portion E2 in the second direction (Y-axis direction) may differ from the lengths of the third edge portion E3 and the fourth edge portion E4 in the third direction (Z-axis direction). In this case, the second direction (Y-axis direction) and the third direction (Z-axis direction) are two perpendicular directions on a plane perpendicular to the first direction (X-axis direction).

[0080] As an example, the lengths of the first edge portion E1 and the second edge portion E2 in the second direction (Y-axis direction) can be less than the lengths of the third edge portion E3 and the fourth edge portion E4 in the third direction (Z-axis direction).

[0081] Additionally, a groove portion G1 may be provided along the edge of the first surface S1. That is, the first surface S1 may include a groove portion G1. In other words, the first surface S1 may have a shape with a protruding structure extending from the center portion toward an adjacent substrate (e.g., the lower substrate). In this specification, the first electrode 120 and the second electrode 150 include groove portions G1 and G2, but as described above, the first electrode 120 and the groove portion G1 provided in the first electrode 120 will be described primarily.

[0082] The groove portion G1 can extend along the edge of the first surface S1 and have a closed loop in the plane YZ. Therefore, the groove portion G1 can be configured to surround a protruding structure located at the center of the first surface S1.

[0083] On the first surface S1, the first edge portions E1 to the fourth edge portions E4 can be configured to be spaced apart from the center portion of the first surface S1 in a first direction. That is, the lower surface GS1a of the groove portion G1 and the center surface S1a of the first surface S1 can be spaced apart from each other. Therefore, the first surface S1 can have a height difference caused by the groove portion G1, and this height difference can correspond to the height H2 of the groove portion G1 in the first direction.

[0084] According to the embodiment, the ratio of the height H2 of the groove portion G1 to the height H1 of the first electrode 120 can be in the range of 1:1.8 to 1:3.2. When this ratio is less than 1:1.8, there is a problem that the resistance of the electrode increases, thereby reducing the performance of the thermoelectric element. In addition, when this ratio is greater than 1:3.2, there is a problem that the first protrusion 180a located in the groove portion separates from the electrode. Furthermore, there may be a problem that the first protrusion formed in the groove portion penetrates the first insulating portion 170a, causing dielectric breakdown on the first insulating portion 170a.

[0085] Additionally, the first surface S1 may include the lower surface GS1a and the side surface GS2a of the groove portion G1, as well as the center surface S1a.

[0086] Furthermore, according to the embodiment, the ratio of the width W1 of the groove portion G1 to the width W2 of the first electrode 120 can be in the range of 1:20 to 1:54.2. When this ratio is less than 1:20, there is a problem of reduced mechanical reliability between the electrode and the protrusion. Conversely, when this ratio is greater than 1:54.2, there is a problem of increased resistance of the electrode.

[0087] The second surface S2 can be configured to face the first surface S1. Alternatively, the second surface S1 can be a surface disposed on a thermoelectric arm electrically connected to the first electrode 120. At least a portion of the second surface S2 can be in contact with or electrically connected to the second conductive semiconductor structure or the first conductive semiconductor structure.

[0088] The third surface S3 can be disposed between the first surface S1 and the second surface S2. When the first surface S1 and the second surface S2 are the lower surface and the upper surface of the first electrode 120, the third surface S3 can correspond to the side surface of the first electrode 120.

[0089] Figure 7 This is a perspective view showing the electrode and the first protrusion according to a first embodiment of the present invention, and Figure 8 This is a cross-sectional view showing the electrode and the first protrusion according to a first embodiment of the present invention.

[0090] Reference Figure 7 and Figure 8 The first protrusion 180a may be disposed in the recessed portion G1 of the first electrode 120. In this case, the first protrusion 180a may have a shape corresponding to the shape of the recessed portion G1. That is, each surface of the first protrusion 180a may be coplanar with one of the first surface S1 and the third surface S3.

[0091] Furthermore, the first protrusion 180a and the first electrode 120 can contact the first insulating portion 170a disposed below the first protrusion 180a and the first electrode 120 as described above. Additionally, the first protrusion 180a and the first electrode 120 can be coupled to the lower substrate via the first insulating portion 170a.

[0092] Furthermore, according to the embodiment, the first electrode 120 includes a groove portion G1 at its edge, and the first protrusion 180a is located in the groove portion G1. Therefore, a protruding electrode protruding from the first electrode (or the first surface) toward the lower substrate can be avoided. That is, the first protrusion 180a can prevent the formation of a protruding electrode. Therefore, since damage to the first insulating portion 170a due to the protrusion will not occur, electrical connection between the first electrode and the lower substrate (or between the second electrode and the upper substrate) due to dielectric breakdown of the insulating portion 170a (or the second insulating portion 170b) can be prevented. That is, the electrical reliability of the thermoelectric element can be improved.

[0093] Figure 9 This is a cross-sectional view showing a thermoelectric element according to a second embodiment of the present invention, and Figure 10 It is shown Figure 9 A magnified view of part K1.

[0094] Reference Figures 9 to 10 As described above, the thermoelectric element according to the second embodiment may include a lower substrate 110, a lower electrode 120, a second conductive semiconductor structure 130, a first conductive semiconductor structure 140, an upper electrode 150, an upper substrate 160, a first insulating portion 170a, and a second insulating portion 170b. Except as described below, the above description can be applied equivalently.

[0095] According to the thermoelectric element based on the second embodiment, each of the first electrodes 120 may include a protruding electrode PR that protrudes from the outermost side of the first surface S1 toward the adjacent substrate.

[0096] First, the protruding electrode PR may include a first protruding electrode PR1a of the first electrode 120 and a second protruding electrode PR1b of the second electrode 150, and in the following, each of the first protruding electrode PR1a and the second protruding electrode PR1b will be described as a protruding electrode PR.

[0097] The protruding electrode PR can be disposed on the lower surface GS1a of the groove portion G1. Alternatively, the protruding electrode PR can also be disposed on the outermost side, i.e., the edge, of the lower surface GS1a of the groove portion G1. Furthermore, the protruding electrode PR can have a closed loop similar to the groove portion G1 in a plane YZ perpendicular to the first direction. Alternatively, the protruding electrode PR can have an open loop in a plane YZ perpendicular to the first direction.

[0098] The height H3 of the protruding electrode PR in the first direction can be less than or equal to the height H2 of the groove portion G1. Due to this construction, the protruding electrode PR may not pass through the first insulating portion 170a or at least a portion thereof. Therefore, not only is the mechanical reliability of the first insulating portion 170a improved, but also the reduction in the electrical reliability of the thermoelectric element due to dielectric breakdown of the first insulating portion 170a can be prevented.

[0099] Additionally, the first insulating portion 170a can contact and couple with the first electrode 120 and the lower substrate 110. In this case, the first insulating portion 170a can extend into the groove portion G1 in the bonding region OR where the first insulating portion 170a overlaps with the first electrode 120. That is, the first insulating portion 170a can also include a first protrusion 180a protruding along the edge of an adjacent electrode (e.g., the first electrode) in the bonding region OR. The first protrusion 180a can overlap with the groove portion G1 in a first direction. Due to protruding electrodes, the shapes of the first protrusion 180a and the second protrusion 180b in the figures may differ from the shapes of the first protrusion 180a and the second protrusion 180b in other figures, which will be described below.

[0100] Furthermore, the first protrusion 180a can contact both the lower surface GS1a and the side surface GS2a of the recessed portion G1. Therefore, the coupling force between the first protrusion 180a and the first electrode 120 can be improved, and the first protrusion 180a can easily support the first electrode 120. Thus, the reliability of the thermoelectric element according to the embodiment can be improved. The description of this embodiment can also be equivalently applied to the second protrusion and the second insulating portion.

[0101] Figure 11 It is shown Figure 10 The diagram shows the modified implementation method.

[0102] Reference Figure 11 As described above, the thermoelectric element according to the modified embodiment may include a lower substrate 110, a lower electrode 120, a second conductive semiconductor structure 130, a first conductive semiconductor structure 140, an upper electrode 150, an upper substrate 160, a first insulating portion 170a, and a second insulating portion 170b. Except as described below, the above description can be applied equivalently.

[0103] According to the modified embodiment, each of the first electrodes 120 may include a protruding electrode PR that protrudes toward the adjacent substrate at the outermost part of the first surface S1. The above can be equivalently applied to the protruding electrode PR.

[0104] The protruding electrode PR can be disposed on the lower surface GS1a of the groove portion G1. Alternatively, the protruding electrode PR can be disposed on the outermost side, i.e., the edge, of the lower surface GS1a of the groove portion G1. Furthermore, the protruding electrode PR can have a closed loop similar to the groove portion G1 in a plane YZ perpendicular to the first direction. Alternatively, the protruding electrode PR can have an open loop in a plane YZ perpendicular to the first direction.

[0105] The height H3 of the protruding electrode PR in the first direction can be less than or equal to the height H2 of the groove portion G1. Due to this construction, the protruding electrode PR may not pass through the first insulating portion 170a or at least a portion thereof. Therefore, not only is the mechanical reliability of the first insulating portion 170a improved, but also the reduction in the electrical reliability of the thermoelectric element due to dielectric breakdown of the first insulating portion 170a can be prevented.

[0106] Furthermore, according to the modified embodiment, the first insulating portion 170a can contact and couple with the first electrode 120 and the lower substrate 110. In this case, the first insulating portion 170a can extend into the groove portion G1 in the bonding region OR where the first insulating portion 170a overlaps with the first electrode 120. The same applies to the second insulating portion 170b and the second electrode 150.

[0107] In this configuration, the first insulating portion 170a may include a first protrusion 180a projecting along the edge of an adjacent electrode (e.g., the first electrode) in the mating region OR. According to a modified embodiment, the first protrusion 180a overlaps with the recessed portion G1 in a first direction, but may be spaced apart from the lower surface GS1a of the recessed portion G1 in the first direction. The height H4 of the first protrusion 180a may be less than the height H2 of the recessed portion G1.

[0108] Furthermore, at least a portion of the first protrusion 180a can contact the side surface GS2a of the recessed portion G1. Even when the first insulating portion 170a is coupled to the lower substrate and the first electrode 120 due to heat and pressure between the lower substrate and the first electrode 120, the first insulating portion 170a will not extend into the entire recessed portion G1 due to its thickness, etc. Because of this construction, an air gap can exist between the first protrusion 180a and the lower surface GS2a in the recessed portion G1. When viewed from above, the air gap can also have a closed loop along the recessed portion G1. Therefore, the electrical connection distance between the first electrode and the lower substrate is increased in a predetermined area, thereby improving the electrical reliability of the first electrode.

[0109] Furthermore, the contact area between the first protrusion 180a and the second protrusion 180b, the first insulating portion 170a and the second insulating portion 170b and the electrodes 120 and 150 can be increased to improve the coupling force. Therefore, the reliability of the thermoelectric element can be improved.

[0110] The above description can also be applied equivalently to the second protrusion and the second insulating part.

[0111] Figure 12 This is a cross-sectional view showing a thermoelectric element according to a third embodiment of the present invention, and Figure 13 It is shown Figure 12 A magnified view of part of K2.

[0112] As described above, the thermoelectric element according to the third embodiment may include a lower substrate 110, a lower electrode 120, a second conductive semiconductor structure 130, a first conductive semiconductor structure 140, an upper electrode 150, an upper substrate 160, a first insulating portion 170a, and a second insulating portion 170b. Except as described below, the above description can be applied equivalently.

[0113] According to the thermoelectric element based on the third embodiment, each of the first electrodes 120 may include a protruding electrode PR that protrudes toward an adjacent substrate at the outermost part of the first surface S1. First, the protruding electrode PR may include a first protruding electrode PR1a of the first electrode 120 and a second protruding electrode PR1b of the second electrode 150, and in the following, each of the first protruding electrode PR1a and the second protruding electrode PR1b will be described as a protruding electrode PR.

[0114] The protruding electrode PR can be disposed on the lower surface GS1a of the groove portion G1. Alternatively, the protruding electrode PR can also be disposed on the outermost side, i.e., the edge, of the lower surface GS1a of the groove portion G1. Furthermore, the protruding electrode PR can have a closed loop similar to the groove portion G1 in a plane YZ perpendicular to the first direction. Alternatively, the protruding electrode PR can have an open loop in a plane YZ perpendicular to the first direction.

[0115] According to the third embodiment, the height H5 of the protruding electrode PR in the first direction can be greater than the height H2 of the recessed portion G1. However, the height difference between the height H5 of the protruding electrode PR in the first direction and the height H2 of the recessed portion G1 can be less than the thickness H6 of the first insulating portion 170a. Due to this structure, even when the protruding electrode PR passes through a portion of the first insulating portion 170a, the protruding electrode PR will not pass through the entire first insulating portion 170a. Therefore, the electrical reliability of the thermoelectric element due to breakage of the first insulating portion 170a can also be prevented.

[0116] The first insulating portion 170a can contact and couple with the first electrode 120 and the lower substrate 110. In this case, the first insulating portion 170a can extend into the groove portion G1 in the bonding region OR where the first insulating portion 170a overlaps with the first electrode 120. That is, the first insulating portion 170a may also include a first protrusion 180a protruding along the edge of an adjacent electrode (e.g., the first electrode) in the bonding region OR. The first protrusion 180a may overlap with the groove portion G1 in a first direction.

[0117] According to the embodiment, the first protrusion 180a can contact both the lower surface GS1a and the side surface GS2a of the recessed portion G1. Therefore, the coupling force between the first protrusion 180a and the first electrode 120 can be further improved, and the first protrusion 180a can easily support the first electrode 120. Therefore, the reliability of the thermoelectric element according to the embodiment can be improved.

[0118] Figure 14 It is shown Figure 13 The diagram shows the modified implementation method.

[0119] As described above, the thermoelectric element according to the modified embodiment may include a lower substrate 110, a lower electrode 120, a second conductive semiconductor structure 130, a first conductive semiconductor structure 140, an upper electrode 150, an upper substrate 160, a first insulating portion 170a, and a second insulating portion 170b. Except as described below, the above description can be applied equivalently. Furthermore, except as described below, the above description can be applied equivalently to the protruding electrode PR, the first insulating portion 170a, and the second insulating portion 170b.

[0120] According to the modified embodiment, the first insulating portion 170a can contact the first electrode 120 and the lower substrate 110, and can couple the first electrode 120 and the lower substrate. In this case, the first insulating portion 170a can extend into the groove portion G1 in the bonding area OR where the first insulating portion 170a overlaps with the first electrode 120.

[0121] In this case, the first insulating portion 170a may include a first protrusion 180a protruding along the edge of an adjacent electrode (e.g., the first electrode) in the bonding region OR. According to a modified embodiment, the first protrusion 180a overlaps with the recessed portion G1 in the first direction, but may be spaced apart from the lower surface GS1a of the recessed portion G1 in the first direction.

[0122] Furthermore, at least a portion of the first protrusion 180a can contact the side surface GS2a of the recessed portion G1. Even when the first insulating portion 170a is coupled to the lower substrate and the first electrode 120 due to heat and pressure between the lower substrate and the first electrode 120, the first insulating portion 170a will not extend into the entire recessed portion G1 due to its thickness, etc. Because of this construction, an air gap can exist between the first protrusion and the lower surface GS2a in the recessed portion G1. When viewed from above, the air gap can also have a closed loop along the recessed portion G1. Therefore, the electrical connection distance between the first electrode and the lower substrate is increased in a predetermined area, thereby improving the electrical reliability of the first electrode.

[0123] Furthermore, the contact area between the first protrusion 180a, the first insulating portion 170a, and the electrode 120 can be increased to improve the coupling force. Therefore, the reliability of the thermoelectric element can be improved.

[0124] Furthermore, according to various embodiments, the first protrusion 180a and the second protrusion 180b may overlap in the vertical direction (e.g., the X-axis direction). Due to this configuration, since the supporting forces generated by the first protrusion 180a and the second protrusion 180b can be applied to the same position in the vertical direction, the reliability of the thermoelectric element can be improved.

[0125] Furthermore, the first protrusion 180a and the second protrusion 180b can have the same shape. For example, based on the first conductive semiconductor structure 140 and the second conductive semiconductor structure 130, the first protrusion 180a and the second protrusion 180b can be the same.

[0126] Therefore, the shape of the groove portion of the first electrode 120 and the shape of the second electrode 150 can be the same. Additionally, the shapes of the first protrusion 180a and the second protrusion 180b located in the groove portion can also be the same. Therefore, since the coupling force between the first electrode 120 and the first substrate 110 via the first insulating portion 170a is similar to the coupling force between the second electrode 150 and the second substrate 160 via the second insulating portion 170b, delamination caused by uneven coupling forces is reduced, thus improving reliability.

[0127] Furthermore, the shapes of the first protrusion 180a and the second protrusion 180b can be different from each other. For example, based on the first conductive semiconductor structure 140 and the second conductive semiconductor structure 130, the shapes of the first protrusion 180a and the second protrusion 180b can be different from each other. Therefore, the coupling force of the first insulating portion 170a and the second insulating portion 170b according to the positional difference between the second electrode 150 and the first electrode 120 can be maintained uniformly. For example, the second electrode 150 and the first electrode 120 can partially overlap in the vertical direction. In addition, the first protrusion 180a and the second protrusion 180b can be arranged spaced apart from each other in the vertical direction. Therefore, the shapes of the first protrusion 180a and the second protrusion 180b can be different in the regions where the first electrode and the second electrode do not overlap in the vertical direction. Therefore, delamination problems caused by non-uniformity can be reduced.

[0128] Furthermore, the height of the first protrusion 180a can be less than or equal to 0.5 times the thickness of the first electrode. Therefore, the occurrence of cracks in the first insulating layer 170a due to the protruding electrode of the first electrode can be minimized.

[0129] Alternatively, the height of the first protrusion 180a may be greater than or equal to 0.5 times the thickness of the first electrode. This configuration improves the coupling force between the first protrusion 180a and the first electrode 120.

[0130] Figure 15 This is a side view showing the electrode and the first protrusion according to another modified embodiment.

[0131] Reference Figure 15 In another modified embodiment of the electrode, at least one of the lower surface GS1a and the side surface GS2a of the groove portion G1 may have a pattern. That is, any one or at least a portion of the lower surface GS1a and the side surface GS2a of the groove portion G1 may have a non-uniform pattern. For example, the surface roughness of the groove portion G1 may be greater than the roughness of other surfaces besides the groove portion. Therefore, the first protrusion 180a and the second protrusion 180b can be more easily coupled to the first electrode 120 to improve mechanical reliability.

[0132] Figures 16a to 16e This is a diagram used to describe a method for manufacturing an electrode according to the first embodiment.

[0133] The method for manufacturing the electrode, the first protrusion, and the second protrusion according to the first embodiment includes an etching process of a substrate member, a coating process of the first and second protrusions, a grinding process of the first and second protrusions to a portion of the region, and a separation process for each electrode. The first protrusion will be described primarily below.

[0134] First, refer to Figure 16a and Figure 16b A portion of the area outside the region corresponding to multiple electrodes can be etched into the substrate component SB.

[0135] The substrate component SB can be formed of a material corresponding to the first electrode and the second electrode. In the following text, the first electrode and the second electrode will be described as electrodes.

[0136] Additionally, areas other than those corresponding to the dimensions of the multiple electrodes can be etched into the substrate component SB. Edge portions EP of the areas corresponding to the dimensions of the multiple electrodes spaced apart from each other can be etched into the substrate component SB to improve manufacturing yield. Furthermore, the width d11 of the edge portions corresponding to adjacent electrodes can be the same.

[0137] Reference Figure 16c The first protrusion 180A can be applied to the etched substrate member SB. Therefore, the first protrusion 180A can be located over the entire area corresponding to the plurality of electrodes. In this case, the material of the first protrusion 180A can be different from the material of the insulating portion.

[0138] Reference Figure 16d The first protrusion 180A on the substrate member SB can be ground to a predetermined area. Due to the grinding, the area corresponding to the multiple electrodes, excluding the edge portion EP, can be exposed. However, the ground first protrusion 180B can be located at the edge portion EP. Therefore, the edge portion EP may not be exposed.

[0139] Additionally, the substrate component SB can be divided into individual electrodes (e.g., a first electrode and a second electrode) along the edge portion EP. That is, a cutting process can be performed. The cutting process can be performed along virtual lines SL1 and SL2 corresponding to the boundary lines between adjacent electrodes among the plurality of electrodes.

[0140] refer to Figure 16e The substrate components can be divided into electrodes 120 and 150 through a cutting process. Electrodes 120 and 150 can be etched to have grooved portions at their edges. The grooved portions can correspond to the edge portion EP.

[0141] The thermoelectric element described in this specification can be applied to thermoelectric devices. A thermoelectric device may include a thermoelectric element and a heat sink coupled to the thermoelectric element.

[0142] Furthermore, the thermoelectric device can be used in a power generation device or a power generation system including such a device. For example, a power generation system may include a power generation device and a fluid pipe, wherein the fluid introduced into the fluid pipe may be a source of heat generated by an engine in a vehicle, ship, etc., a power plant, a steel mill, etc. However, the present invention is not limited thereto. Additionally, the temperature of the fluid discharged from the fluid pipe is lower than the temperature of the fluid introduced into the fluid pipe. For example, the temperature introduced into the fluid pipe may be higher than or equal to 100°C, preferably 200°C or higher, and more preferably in the range of 220°C to 250°C, but is not limited thereto, and may vary depending on the temperature difference between the low-temperature and high-temperature portions of the thermoelectric element. Therefore, the thermoelectric element according to embodiments of the present invention can operate in power generation devices, cooling devices, heating devices, etc.

[0143] Although the invention has been described with reference to exemplary embodiments thereof, those skilled in the art will understand that various changes and modifications may be made to the invention without departing from the spirit and scope of the invention as defined by the following appended claims.

Claims

1. A thermoelectric element, comprising: First insulating part; A plurality of first electrodes are disposed on the first insulating portion; Multiple second electrodes are disposed above the first electrode; A first conductive semiconductor structure and a second conductive semiconductor structure are disposed spaced apart from each other between the first electrode and the second electrode; as well as The second insulating portion is disposed on the second electrode. The first insulating portion includes a first protrusion that protrudes toward the first electrode. The second insulating portion includes a second protrusion that protrudes toward the second electrode. Each of the first electrode and the second electrode includes a groove portion disposed at an edge of the surface facing the adjacent substrate. When viewed from above, the groove portion has a closed loop. Each of the first electrode and the second electrode further includes a protruding electrode, which is disposed at the edge of the lower surface of the groove portion. The height of the protruding electrode in the vertical direction is less than the height of the groove portion in the vertical direction.

2. The thermoelectric element of claim 1, wherein, The first protrusion and the second protrusion overlap in the vertical direction.

3. The thermoelectric element of claim 2, wherein, Based on the first conductive semiconductor structure and the second conductive semiconductor structure, the first protrusion and the second protrusion have the same shape.

4. The thermoelectric element of claim 2, wherein, Based on the first conductive semiconductor structure and the second conductive semiconductor structure, the first protrusion and the second protrusion have different shapes.

5. The thermoelectric element of claim 1, wherein, The first protrusion and the second protrusion are arranged at a distance from each other in the vertical direction.

6. The thermoelectric element of claim 1, wherein, The height of the first protrusion is less than or equal to 0.5 times the thickness of the first electrode.

7. The thermoelectric element according to claim 1, wherein, The height of the first protrusion is greater than or equal to 0.5 times the thickness of the first electrode.

8. The thermoelectric element according to claim 1, wherein, Each of the first protrusion and the second protrusion is disposed in the groove portion.

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