Upper heat sink

Abstract

To provide a resistor with good heat dissipation and a method for manufacturing the same.SOLUTION: A resistor 300 includes a resistive element 320 and a plurality of upper heat dissipation elements 310a, 310b. A first heat dissipation element is coupled to the top surface of the resistive element by an adhesive 330 and is curved downwardly toward the resistive element in proximity to the first side of the resistive element, the bottom surface of the first heat dissipation element includes a curved first curved portion that also forms the outer portion of the heat dissipation element. A second heat dissipation element is also coupled to the top surface of the resistive element with an adhesive and is curved downward toward the resistive element in proximity to the second side of the resistive element, the bottom surface of the second heat dissipation element includes a curved second curved portion that also forms the outer portion of the heat dissipation element. A gap is provided between the first heat dissipation element and the second heat dissipation element, and a dielectric 340a fills the gap and electrically isolates components from each other.SELECTED DRAWING: Figure 3A

Description

Related Applications

[0001] This application claims priority to U.S. Provisional Application No. 62 / 584,505, filed November 10, 2017, and U.S. Provisional Application No. 16 / 181,006, filed November 5, 2018, the contents of which are incorporated by reference. [Technical field]

[0002] The present invention relates to electronic components, and more particularly to resistors and resistor fabrication. [Background technology]

[0003] Resistors are passive components used in circuits to provide electrical resistance by converting electrical energy into heat, which is then dissipated. Resistors can be used in electrical circuits for many purposes, such as limiting current, dividing voltages, detecting current levels, adjusting signal levels, and biasing active devices. In the case of high power resistors, required for applications such as automotive controls, such resistors are required to dissipate high wattages of power. The requirement that these resistors have a relatively high resistance value requires supporting resistive elements that are extremely thin and capable of maintaining their resistance for long periods of time under full power load. Summary of the Invention

[0004] The resistor and a method for making the resistor are described below.

[0005] In one embodiment, the resistor includes a resistive element and a plurality of separate conductive elements forming a heat dissipating element, the plurality of conductive elements may be electrically insulated from one another by a dielectric material and thermally coupled to the resistive element by an adhesive material disposed between each of the plurality of conductive elements and a surface of the resistive element, and the plurality of conductive elements may be thermally coupled to the resistive element by solderable terminals.

[0006] Another embodiment of the resistor of the present invention includes a resistive element having a top surface, a bottom surface, a first side surface, and a second side surface opposite the first side surface. The first and second conductive elements are bonded to the top surface of the resistive element by an adhesive. The first and second conductive elements function as heat dissipation elements. A gap is provided between the first and second conductive elements. The first and second conductive elements are positioned such that a portion of the adhesive is exposed on the top surface of the resistive element. A first conductive layer is positioned along the bottom of the resistive element, and a second conductive layer is positioned along the bottom of the resistive element. A dielectric covers the top surfaces of the first and second conductive elements and fills the gap between the first and second conductive elements. A dielectric is deposited on the exterior surface of the resistor. The dielectric may be deposited on both the top and bottom surfaces of the resistor.

[0007] The invention also relates to a method for manufacturing a resistor, which includes laminating a conductor to a resistive element using an adhesive, plating an electrode layer on the bottom of the resistive element, masking and patterning the conductor to separate the conductor into heat dissipation elements, depositing a dielectric on the top and bottom surfaces of the resistor, and plating a solderable layer on the sides of the resistor. In one embodiment, the resistive element can be patterned, e.g., using chemical etching, and thinned, e.g., using a laser, to achieve a target resistance value.

[0008] Another embodiment of the resistor has a resistive element bonded to a first heat dissipation element and a second heat dissipation element by an adhesive, the first heat dissipation element and the second heat dissipation element being electrically insulated from each other by a dielectric. An electrode is provided on a bottom surface of the resistive element. First and second solderable parts of the resistor may be provided on at least the first heat dissipation element, the second heat dissipation element and the resistive element. The first and second heat dissipation elements receive most of the heat generated by the resistor while receiving little or no current and without it flowing. The electrodes carry most of the device current. [Brief description of the drawings]

[0009] The present invention will now be described in detail with reference to the accompanying drawings.

[0010] [Figure 1A] FIG. 1A is a cross-sectional view of one embodiment of a resistor. [Figure 1B] FIG. 1B is a cross-sectional view of one embodiment of a resistor on a circuit board. [Figure 1C] FIG. 1C is a cross-sectional view of one embodiment of a resistor mounted on a circuit board. [Figure 2A] FIG. 2A is a cross-sectional view of one embodiment of a resistor with a swaged or stepped surface on the top corners of each heat dissipation element. [Figure 2B] FIG. 2B is a cross-sectional view of one embodiment of a resistor with a swaged or stepped surface on the top corners of each heat dissipation element. [Figure 2C] FIG. 2C is a cross-sectional view showing a resistor mounted on a circuit board with a swaged or stepped surface on the top corners of each heat dissipation element. [Figure 2D] FIG. 2D is a cross-sectional view of one embodiment of a resistor with a swaged or stepped surface on the top corners of each heat dissipation element, showing a portion of each heat dissipation element closer to the resistive element. [Figure 2E] FIG. 2E is a cross-sectional view of a resistor mounted on a circuit board with a swaged or stepped surface on the upper corners of each heat dissipation element, showing a portion of each heat dissipation element closer to the resistive element. [Figure 2F] FIG. 2F is a top view of the resistor embodiment shown in FIGS. 2A and 2D. [Figure 2G] FIG. 2G is a side view of the resistor embodiment shown in FIGS. 2A and 2D. [Figure 2H] FIG. 2H is a bottom view of the resistor embodiment shown in FIGS. 2A and 2D. [Figure 3A] FIG. 3A is a cross-sectional view of an example resistor showing the exterior of the heat dissipation element folded over the resistive element. [Figure 3B] FIG. 3B is a cross-sectional view of one embodiment of a resistor showing the exterior of the heat dissipation element bent toward the resistive element mounted on a circuit board. [Figure 4A]FIG. 4A is a top view of one embodiment of a resistor. [Figure 4B] FIG. 4B is a side view of the resistor of FIG. 4A including an enlarged view of a portion of the resistor. [Figure 4C] FIG. 4C is a bottom view of the resistor of FIG. 4A including an enlarged view of a portion of the resistor. [Figure 4D] FIG. 4D is an isometric view of the resistor of FIG. 4A, partially cut away to show internal components or layers. [Figure 5A] FIG. 5A is a top view of the resistor. [Figure 5B] FIG. 5B is a side view of the resistor of FIG. 5A including an enlarged view of a portion of the resistor. [Figure 5C] FIG. 5C is a bottom view of the resistor of FIG. 5A including an enlarged view of a portion of the resistor. [Figure 5D] FIG. 5D is an isometric view of the resistor of FIG. 5A, partially cut away to reveal internal components or layers. [Figure 6A] FIG. 6A is a top view showing a resistor. [Figure 6B] FIG. 6B is a side view of the resistor of FIG. 6A including an enlarged view of a portion of the resistor. [Figure 6C] FIG. 6C is a bottom view of the resistor of FIG. 6A including an enlarged view of a portion of the resistor. [Figure 6D] FIG. 6D is an isometric view of the resistor of FIG. 6A, partially cut away to reveal internal components or layers. [Figure 7] FIG. 7 is a flow chart showing one embodiment of a manufacturing method. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0011] The following description uses certain terms for purposes of illustration only and not for purposes of limitation. The terms "right", "left", "top" and "bottom" and the like refer to directions in the accompanying drawings to which reference is made. In the claims and the corresponding specification, the singular refers to the plural, unless otherwise specified. These terms and the like mean one or more of what is specifically described. The term "at least one" before "A, B or C" and the like may refer to A, B or C individually or in any combination thereof.

[0012] FIG. 1A illustrates a cross-sectional view of an exemplary resistor 100. The resistor 100 illustrated in FIG. 1 includes a resistive element 120 disposed across the width of the resistor 100 and disposed between a first solderable terminal 160a and a second solderable terminal 160b, as described in more detail below. In the relative position illustrated in FIG. 1A for purposes of illustration, the resistive element has a top surface 122 and a bottom surface 124. The resistive element 120 is preferably a foil resistor. The resistive element may be formed from, but is not limited to, copper, copper alloys, nickel, aluminum, or manganese, or combinations thereof. Additionally, the resistive element may be formed from copper-nickel-manganese alloy (CuNiMn), copper-manganese-tin alloy (CuMnSn), copper-nickel alloy (CuNi), nickel-chromium-aluminum alloy (NiCrAl), nickel-chromium alloy (NiCr), or other alloys known to those skilled in the art that may be used as foil resistors. As illustrated in FIG. 1A, the resistive element 120 has a width "W." 1A, resistive element 120 has a height or thickness "H." Opposite outer sides or surfaces of resistive element 120 may be generally planar or substantially flat.

[0013] As shown in FIG. 1A, the first heat dissipation element 110a and the second heat dissipation element 110b are adjacent to opposite ends of the resistive element 120, preferably with a gap 190 between the first heat dissipation element 110a and the second heat dissipation element 110b. The heat dissipation elements 110a and 110b are made of a thermally conductive material, preferably copper, such as C110 copper or C102 copper. Other metals exhibiting other thermally conductive properties, such as aluminum, may also be used for the heat dissipation elements, and one of ordinary skill in the art would be familiar with metals that may be used for the heat dissipation elements 110a and 110b. The first heat dissipation element 110a and the second heat dissipation element 110b extend at least partially to the outer edge (or outer surface) of the resistive element 120.

[0014] The heat dissipation elements 110a and 110b may be laminated, adhered, bonded or otherwise attached to the resistive element 120 via an adhesive 130. Examples of adhesives include, but are not limited to, DUPONT®, PYRALUX®, BOND PLY® or other acrylic, epoxy, polyimide or alumina filled resin adhesives and may be in sheet or liquid form. Additionally, the adhesive 130 may be comprised of a material that is both electrically insulating and thermally conductive. The adhesive 130 may extend along the width "W" of the top surface 122 of the resistive element 120.

[0015] The heat dissipation elements 110a and 110b are set so as to be located above the resistor and spaced apart from the circuit board when the resistor is mounted on a circuit board such as a printed circuit board (PCB), as shown in FIG. 1C.

[0016] 1A, first and second electrode layers 150a, 150b (sometimes referred to as conductive layers) are disposed along at least portions of opposing ends of the bottom surface 124 of the resistive element 120. The electrode layers 150a, 150b have opposing outer edges that preferably align with opposing outer edges (or exterior surfaces) of the resistive element 120. The first and second electrode layers 150a, 150b are preferably plated onto the bottom surface 124 of the resistive element 120. In a preferred embodiment, copper is used as the electrode layers, although any plateable, highly thermally conductive metal may be used, as is well known to those skilled in the art.

[0017] The outer edges (outer faces) of the resistive element 120 and the heat dissipating elements 110a and 110b form solderable surfaces that receive the solderable terminals 160a and 160b, also known as terminal plating. The resistive element 120 and the heat dissipating elements 110a and 110b preferably form planar, flat or smooth outer faces so that the outer edges of the resistive element 120 and the heat dissipating elements 110a and 110b, respectively, are aligned. As used herein, "flat" means "generally flat" and "smooth" means "within normal manufacturing tolerances." Note that the outer faces may be somewhat or more circular, arcuate, curved or corrugated, depending on the process used to form the resistors, but any of these may be considered "flat."

[0018] The solderable terminals 160a and 160b may be individually attached to the side ends 165a and 165b of the resistor 100 and the resistor 100 may be soldered to a circuit board, as described in more detail below with reference to FIG. 1B. As shown in FIG. 1A, the solderable terminals 160a and 160b preferably have portions that extend at least partially along the bottom surfaces 152a and 152b of the electrode layers 150a and 150b. As shown in FIG. 1A, the solderable terminals 160a and 160b preferably have portions that extend at least partially along the top surfaces 115a and 115b of the heat dissipation elements 110a and 110b. Additionally, the use of a conductive layer such as 150a and 150b on the side of the resistive element closest to the printed circuit board (PCB), as shown in FIG. 1B and described herein, aids in forming a strong solder joint during solder reflow and in centering the resistor on the PCB pad.

[0019] Figure 1B illustrates an exemplary resistor 100 mounted to a circuit board 170. In the embodiment illustrated in Figure 1B, resistor 100 is mounted to a printed circuit board (PCB) 170 using solder connections 180a and 180b between solderable terminals 160a and 160b and corresponding solder pads 175a and 175b on the circuit board 170.

[0020] The heat dissipation elements 110a and 110b are coupled to the resistive element 120 by adhesive 130. It should be noted that the heat dissipation elements 110a and 110b may be thermally and / or mechanically and / or electrically coupled / connected to the resistive element 120 or may be adhered, bonded or mounted by other means. In particular, solderable terminals 160a and 160b provide thermal and electrical connectivity between the resistive element 120 and the heat dissipation elements 110a and 110b. The thermal, electrical and / or mechanical coupling / connection between the resistive element 120 and the respective side ends of the heat dissipation elements 110a and 110b allows the heat dissipation elements 110a and 110b to be used as structural members of the resistor 110 and as heat spreaders. The use of heat dissipation elements 110a and 110b as structural components of resistor 100 allows resistive element 120 to be thinner than a freestanding resistive element, and resistor 100 can have a resistance value of about 1 mΩ to 20Ω using foil thicknesses of about 0.015 inches to about 0.001 inches. In addition to providing support for resistive element 120, heat dissipation elements 110a and 110b can be used efficiently as heat spreaders, allowing resistor 100 to effectively dissipate heat and thus have a higher power rating than resistors that do not use a heat spreader. For example, a typical power rating for a 2512 size metal strip resistor is 1 W. Using the embodiments described herein, a 2512 size metal strip resistor can have a power rating of 3 W.

[0021] Additionally, use of resistor 100 as shown in Figures 1A-1C reduces or eliminates the risk of resistor failure due to thermal coefficient of expansion (TCE).

[0022] In FIG. 1C, the dielectric coating 140 is shown with dot shading. It is noted that the dielectric coating 140 may be applied to selected portions or the entire exterior surface of the resistor 100. The dielectric 140 may be formed on the surface of the resistor 100, such as by a coating process. The dielectric 140 fills spaces or gaps and electrically insulates the components from one another. As shown in FIG. 1C, a first dielectric 140a is formed on the top of the resistor. The first dielectric 140a preferably extends between portions of the solderable terminals 160a and 160b and covers the exposed top surfaces 115a and 115b of the heat dissipation elements 110a and 110b. The first dielectric 140a also fills and separates the gap 190 between the heat dissipation elements 110a and 110b, and covers the exposed portions of the adhesive 130 facing the gap 190. Second dielectric 140b is formed along the bottom surface of resistive element 120 between portions of solderable terminals 160a and 160b and covers exposed portions of electrode layers 150a and 150b and bottom surface 124 of resistive element 120.

[0023] Based on modeling, it is believed that approximately 20% to approximately 50% of the heat generated during use of resistor 100 flows to heat dissipation elements 110a and 110b, thereby dissipating heat. Based on modeling, it is believed that heat dissipation elements 110a and 110b contain little or no current flowing through resistor 100, and that the current flowing through heat dissipation elements 110a and 110b is zero or close to zero during use. It is expected that all, or nearly all, of the current will flow to electrode layers 150a and 150b and then to resistive element 120.

[0024] 2A is a cross-sectional view of an exemplary resistor 200 according to another embodiment. In this embodiment, resistor 200 has swages 209a and 209b at its top corners, where the swage may be a step, a section with two different heights, a depression, a groove, a ridge, or any other shaped section or formation. In one example, swages 209a and 209b are steps at the top and outer corners of heat dissipation elements 210a and 210b. Solderable elements 260a and 260b covering heat dissipation elements 210a and 210b also have corresponding swages at the top and outer corners. The portions of solderable elements 260a and 260b having the swages will be in closer proximity to resistive element 220, as will be described in more detail below.

[0025] The swages 209a and 209b provide the heat dissipation elements 210a and 210b with inner top surfaces 215a and 215b that extend or match along the same level or plane, preferably lower than the top of the dielectric 240a, and with lower outer top surfaces 216a and 216b that extend or match along the same level or plane, lower than the innermost top surface. As shown, the heat dissipation elements 210a and 210b with swages 209a and 209b are used such that the height of the inner top surfaces 215a and 215b is equal to or greater than the height of the lower outer top surfaces 216a and 216b. The swages 209a and 209b provide the heat dissipation elements 210a and 210b with an overall length, indicated at 291a and 291b, and lengths 292a and 292b to the beginning of the swages 209a, 209b portions.

[0026] The swages 209a and 209b form an outer portion of the heat dissipation elements 210a and 210b having a height indicated as SH1 in FIG. 2B, and an inner portion having a height indicated as SH2. In a preferred embodiment, SH2 is greater than SH1. The total height SH2 of the heat dissipation elements 210a and 210b can be, for example, on average, more than twice the height H1 of the resistive element 220.

[0027] It is noted that the swages 209a and 209b can have one or more variations in shape to form stepped, angled, or rounded tops on the heat dissipation elements 210a and 210b. In this embodiment, the solderable elements 260a and 260b covering the heat dissipation elements 210a and 210b can have a corresponding shape.

[0028] The resistor 200 shown in FIG. 2B includes a resistive element 220 that is preferably located across the entire area of ​​the resistor 200, for example, along at least a portion of the length and width of the resistor 200. The resistive element has a top surface 222 and a bottom surface 224. The resistive element 220 is preferably a foil resistor. The resistive element may be formed from, but is not limited to, copper, copper alloys, nickel, aluminum, or manganese, or combinations thereof. Additionally, the resistive element may be formed from copper-nickel-manganese alloy (CuNiMn), copper-manganese-tin alloy (CuMnSn), copper-nickel alloy (CuNi), nickel-chromium-aluminum alloy (NiCrAl), nickel-chromium alloy (NiCr), or other alloys known to those skilled in the art that may be used as foil resistors. As shown in FIG. 2B, the resistive element 220 has a width "W2". As shown in FIG. 2B, the resistive element 220 has a height or thickness "H1". The opposing exterior sides or surfaces of resistive element 220 may be generally planar or substantially flat.

[0029] First and second solderable terminals 260a and 260b cover opposite ends of the resistor and may be formed in the same manner as described for solderable terminals 160a and 160b. Solderable terminals 260a and 260b extend from electrodes 250a and 250b along the sides of the resistor and along at least a portion of the inner top surfaces 215a and 215b of heat dissipation elements 210a, 210b.

[0030] The first and second heat dissipation elements 210a and 210b are adjacent to opposite ends of the resistive element 220, preferably with a gap 290 between the first and second heat dissipation elements 210a and 210b. The heat dissipation elements 210a and 210b are made of a thermally conductive material, preferably copper, such as C110 copper or C102 copper. Other metals exhibiting other thermally conductive properties, such as aluminum, may also be used for the conductive element, and one of ordinary skill in the art would be familiar with metals that may be used for the conductive element. The first and second heat dissipation elements 210a and 210b extend to the outer edge (or outer surface) of the resistive element 220. The outermost side edges (sides) of the heat dissipation elements 210a, 210b and the outer edge (or outer surface) of the resistive element 220 are aligned to form a flat outer surface of the resistor.

[0031] Heat dissipation elements 210a and 210b may be laminated, adhered, bonded or otherwise attached to resistive element 220 via adhesive 230. Examples of adhesives include, but are not limited to, DUPONT®, PYRALUX®, BOND PLY® or other acrylic, epoxy, polyimide or alumina filled resin adhesives and may be in sheet or liquid form. Additionally, adhesive 230 may be comprised of a material that is both electrically insulating and thermally conductive. Adhesive 230 preferably extends along the entire width “W2” of top surface 222 of resistive element 220.

[0032] FIG. 2C shows that when the resistor is mounted on the circuit board 270, the heat dissipation elements 210a and 210b can be positioned such that they are located above the resistor and spaced apart from the circuit board 270.

[0033] First and second electrode layers 250a, 250b (sometimes referred to as conductive layers) are disposed along at least portions of opposing ends of the bottom surface 224 of the resistive element 220. The electrode layers 250a, 250b have opposing outer edges that preferably align with opposing outer edges (or exterior surfaces) of the resistive element 220. The first and second electrode layers 250a, 250b are preferably plated onto the bottom surface 224 of the resistive element 220. In a preferred embodiment, the electrode layers may be copper, although any plateable, highly thermally conductive metal may be used, as is well known to those skilled in the art.

[0034] The outer edges (or outer faces) of the resistive element 220 and the thermal dissipation elements 210a and 210b form solderable surfaces that receive the solderable terminals 260a and 260b, also known as terminal plating. The portions of the outer faces (or outer faces) underlying the swages 209a and 209b of the solderable terminals 260a and 260b preferably form planar, flat or smooth outer faces. As used herein, "flat" means "generally flat" and "smooth" means "generally smooth" within "normal manufacturing tolerances." It should be noted that the outer faces of the solderable terminals 260a and 260b may be somewhat or more circular, arcuate, curved or corrugated depending on how the resistor is formed, but any of these may be considered "flat."

[0035] 2C, solderable terminals 260a and 260b may be attached to side ends 265a and 265b of resistor 200, respectively, and resistor 200 may be soldered to circuit board 270. Solderable terminals 260a and 260b preferably have portions that extend at least partially along bottom surfaces 252a and 252b of electrode layers 250a and 250b. Solderable terminals 260a and 260b preferably have portions that extend at least partially along top surfaces 215a and 215b of heat dissipation elements 210a and 210b.

[0036] 2C, the use of electrode layers such as 250a and 250b on the side of the resistive element closest to a circuit board (PCB) 270 aids in forming a strong solder joint during solder reflow and in centering resistor 200 on the PCB pads. Resistor 200 is mounted to circuit board 270 using solder connections 280a and 280b between solderable terminals 260a and 260b and corresponding solder pads 275a and 275b on circuit board 270.

[0037] The heat dissipation elements 210a and 210b are coupled to the resistive element 220 by adhesive 230. It should be noted that the heat dissipation elements 210a and 210b may be thermally and / or mechanically and / or electrically coupled / connected or otherwise adhered, bonded or mounted to the resistive element 220. Additionally, solderable terminals 260a and 260b provide thermal connectivity between the resistive element 220 and the heat dissipation elements 210a and 210b.

[0038] Resistor 200 may be applied, such as by coating, to a portion of the exterior surface of resistor 200 or to exposed surfaces, as shown. Dielectric coatings 140a and 140b are preferred. Dielectrics 240a and 240b fill spaces or gaps and electrically insulate the components from one another. A first dielectric 240a is formed on top of the resistor. This first dielectric 240a preferably extends between portions of solderable terminals 260a and 260b and covers the exposed top surfaces 215a and 215b of heat dissipation elements 210a and 210b. First dielectric 240a also fills and separates gap 290 between heat dissipation elements 210a and 210b, and covers the exposed portions of adhesive 230 facing gap 290. The second dielectric 240b extends between the solderable terminals 260a and 260b along the bottom surface 224 of the resistive element 220 and covers the exposed portions of the electrode layers 250a and 250b. A gap 271 may be provided between the second dielectric 240b and the circuit board 270 when the resistor is mounted.

[0039] 2D is a cross-sectional view of an exemplary resistor 200 in one embodiment with portions of heat dissipation elements 210a and 210b, respectively, closer to resistive element 220. Swages 209a and 209b can be formed by compressing or otherwise pressing portions of heat dissipation elements 210a and 210b toward resistive element 220 such that at least a portion of each heat dissipation element extends toward resistive element 220. Adhesive layer 230 can also be compressed in predetermined regions 201. The compressive force is the result of a die / punch that presses heat dissipation elements 210a and 210b downward from top surfaces 215a and 215b to form swages 209a and 209b. In this embodiment, adhesive layer 230 may be compressed or made thinner in areas 201 under swages 209a and 209b such that height AH2 of adhesive layer 230 under swages 209a and 209b is less than height AH1 of the remainder of the adhesive layer. Extending portions of heat dissipation elements 210a and 210b toward resistive element 220 brings heat dissipation elements 210a, 210b closer to resistive element 220 (i.e., AH2), facilitating heat transfer from the resistive elements to heat dissipation elements 210a and 210b.

[0040] Fig. 2E is a diagram showing a resistor having portions of heat dissipation elements 210a, 210b closely spaced by a resistive element 220 mounted on a circuit board 270. The structure shown in Fig. 2E may be constructed with components similar to those described with reference to Fig. 2C, and therefore the above description may be referred to.

[0041] FIG. 2F is a top view of the resistor embodiment shown in FIGS. 2A and 2D with the internal portions of the resistor shown in phantom.

[0042] FIG. 2G is a side view of the resistor embodiment shown in FIGS. 2A and 2D with the internal portions of the resistor shown in phantom.

[0043] FIG. 2H is a bottom view of the resistor embodiment shown in FIGS. 2A and 2D with the internal portions of the resistor shown in phantom.

[0044] The resistive element 220 is thermally, electrically, and / or mechanically coupled / connected to the side ends of the heat dissipation elements 210a and 210b, respectively, allowing the heat dissipation elements 210a and 210b to be used as structural members of the resistor 200 and as heat spreaders.

[0045] 3A is a cross-sectional view of an exemplary resistor 300 constructed in accordance with another embodiment of the present invention. The resistor 300 includes a resistive element 320 that is preferably located across the entire area of ​​the resistor 300, for example, along at least a portion of the length and width of the resistor 300. The resistive element 320 has a top surface 322 and a bottom surface 324. The resistive element 320 is preferably a foil resistor. Furthermore, the resistive element may be formed from, but is not limited to, copper, a copper alloy, a nickel alloy, an aluminum alloy, a manganese alloy, or combinations thereof. Furthermore, the resistive element may be formed from copper-nickel-manganese alloy (CuNiMn), copper-manganese-tin alloy (CuMnSn), copper-nickel alloy (CuNi), nickel-chromium-aluminum alloy (NiCrAl), nickel-chromium alloy (NiCr), or other alloys known to those skilled in the art that may be used as foil resistors. The resistive element 320 has a width "W3". Additionally, resistive element 320 has a height or thickness “H2.” The outer sides or surfaces of resistive element 320 in opposing directions may be generally planar or substantially flat.

[0046] The first and second heat dissipation elements 310a, 310b are adjacent opposite ends of the resistive element 320, preferably with a gap 390 between the first and second heat dissipation elements 310a, 310b. The heat dissipation elements 310a, 310b are made of a thermally conductive material, preferably copper, such as C110 copper or C102 copper. Other metals exhibiting other thermally conductive properties, such as aluminum, may also be used for the heat dissipation elements, and one of ordinary skill in the art would be familiar with metals that may be used as conductive elements.

[0047] Heat dissipation elements 310a and 310b may be laminated, adhered, bonded or otherwise attached to resistive element 320 via adhesive 330. Examples of adhesives include, but are not limited to, DUPONT®, PYRALUX®, BOND PLY® or other acrylic, epoxy, polyimide or alumina filled resin adhesives and may be in sheet or liquid form. Additionally, adhesive 330 may be comprised of a material that is both electrically insulating and thermally conductive. Adhesive 330 may extend along the entire width “W3” of top surface 322 of resistive element 320.

[0048] First and second electrode layers 350a, 350b (sometimes referred to as conductive layers) are disposed along at least portions of opposing ends of the bottom surface 324 of the resistive element 320. The electrode layers 350a, 350b have opposing outer edges that preferably align with the opposing outer edges (or exterior surfaces) of the resistive element 320. The first and second electrode layers 350a, 350b are preferably plated onto the bottom surface 324 of the resistive element 320. In a preferred embodiment, copper may be used for the electrode layers. However, any metal that can be plated and has good thermal conductivity may be used, as is well known to those skilled in the art.

[0049] As shown, the dielectric coatings 340a and 340b of the resistor 300 may be applied (such as by coating) to the exterior or exposed surfaces of some of the resistor 300. The dielectrics 340a and 340b fill spaces or gaps and electrically insulate the components from one another. A first dielectric 340a is formed on the top of the resistor 300. The first dielectric 340a covers the top surfaces 315a and 315b of the heat dissipation elements 310a and 310b. The first dielectric 340a also fills and separates the gap 390 between the heat dissipation elements 310a and 310b and covers the exposed portion of the adhesive layer 330 facing the gap 390. The second dielectric 340b is formed on the bottom surface 324 of the resistive element 320 and covers portions of the electrode layers 350a and 350b.

[0050] As shown in FIG. 3A, a portion of each of the heat dissipation elements 310a and 310b may be closer to the resistive element 320. The swages 309a and 309b may be formed by compressing or otherwise pressing portions of the heat dissipation elements 310a and 310b toward the resistive element 320. The adhesive layer 330 may also be compressed in the predetermined area 301. The compressive force is the result of a die / punch that presses the heat dissipation elements 310a and 310b down from the top surfaces 315a and 315b to form the swages 309a and 309b. In this embodiment, the adhesive layer 330 may be thinned in the area 301 under the swages 209a and 209b and bend down along the heat dissipation elements 310a and 310b.

[0051] Each heat dissipation element has at least a portion, such as an extension portion 302, that extends toward, adjacent to, or around the resistive element 320, as the case may be. The extension portion 302 of the first heat dissipation element 310a may be pressed or otherwise extended along the outer edge (or outer surface) of the adhesive layer 330. In one embodiment, the extension portion 302 of the first heat dissipation element 310a and the extension portion 302 of the second heat dissipation element 310b may extend toward the resistive element 320. The outer edges (sides) of the extension portions 302 of the heat dissipation elements 310a, 310b and the outer edge (or outer surface) of the resistive element 320 may be aligned, thus forming the outer surface of the resistor 300.

[0052] The bottom of adhesive layer 330 and heat dissipation elements 310a and 310b may be curved downwardly towards resistive element 320 within bend region 301. As shown in the close-up view, the bottom edges of heat dissipation elements 310a and 310b, as well as the outer edge of adhesive layer 330, may be rounded.

[0053] In this disclosure, a swage refers to a step, depression, groove, ridge, or other shaped formation. In one embodiment, swages 309a and 309b can be considered as steps at the top and outer corners of heat dissipation elements 310a and 310b.

[0054] The swages 309a and 309b form inner top surfaces 315a and 315b on the heat dissipation elements 310a and 310b that extend or match along the same level or plane, preferably lower than the top of the dielectric 340a, and lower outer top surfaces 316a and 316b that extend or match along the same level or plane, lower than the uppermost inner top surface. As shown, the use of heat dissipation elements 310a and 310b with swages 309a and 309b results in the height of the inner top surfaces 315a and 315b being equal to or greater than the height of the lower outer top surfaces 316a and 316b. Swages 309a and 309b further provide heat dissipation elements 310a and 310b with an overall length indicated at 391a and 391b, as well as lengths 391a and 391b to the beginnings of portions of swages 309a, 309b indicated at 392a and 392b.

[0055] The swages 309a and 309b form an outer portion of the heat dissipation elements 310a and 310b having a height SH3 and an inner portion of the heat dissipation elements 310a and 310b having a height SH4. In a preferred embodiment, SH4>SH3. The total height SH4 of the heat dissipation elements 310a and 310b can be, for example, on average twice the height H2 of the resistive element 320.

[0056] It should be noted that swages 309a and 309b can have one or more variations in shape to form stepped, angled, or rounded tops on heat dissipation elements 310a and 310b.

[0057] The first solderable terminal 360a and the second solderable terminal 306b may be formed on opposite ends of the resistor 300 in the same manner as described for the solderable terminals 160a, 160b and 260a, 260b. The solderable terminals 360a, 360b extend from the electrodes 350a, 350b along the sides of the resistor and along at least a portion of the inner top surfaces 315a and 315b of the heat dissipation elements 310a, 310b. The first dielectric 340a preferably extends between the solderable terminals 360a and 360b on the top surface of the resistor 300 and the second dielectric 340b preferably extends between portions of the solderable terminals 360a and 360b along the bottom surface 324 of the resistive element 320.

[0058] The outer edges (or outer surfaces) of the resistive element 320 and the thermal dissipation elements 310a, 310b form solderable surfaces that receive the solderable terminals 360a and 360b, also known as terminal plating. The portions of the outer edges (or outer surfaces) of the solderable terminals 360a and 360b that underlie the swages 309a and 309b form planar, or flat, or smooth outer surfaces. As used herein, "flat" means "generally flat," "smooth" means "generally smooth," and "generally smooth" means "within normal manufacturing tolerances." It should be noted that the outer surfaces of the solderable terminals 360a and 360b may be somewhat or more circular, arcuate, curved, or corrugated under the swages 309a and 309b depending on how the resistors are formed, but any of these may be considered "flat." Compressing the adhesive layer 330 and the thermal dissipation elements 310a and 310b allows the thermal dissipation elements 310a, 310b and the resistive element 320 to come into closer proximity within the curved region 301. This accelerates adhesion of the solderable terminals 310a, 310b to the thermal dissipation elements 310a, 310b and the resistive element 320.

[0059] The solderable terminals 360a and 360b covering the heat dissipation elements 310a and 310b will have corresponding swages in the top and outer corners. In this manner, the solderable elements 360a and 360b having the swages are in closer proximity to the resistive element 320.

[0060] Solderable terminals 360a and 360b preferably have portions that extend partially along top surfaces 315a and 315b of heat dissipation elements 310a and 310b.

[0061] As described above, compressing and folding the adhesive layer 330 brings the thermal dissipation elements 310a, 310b and the resistive element 320 into closer proximity to one another. Solderable terminals 360a and 360b can bridge the adhesive 330.

[0062] 3B is a diagram showing a state in which, when the resistor is attached to a circuit board 370 (PCB 370), the heat dissipation elements 310a and 310b are provided so that the heat dissipation elements 310a and 310b are located above the resistor and spaced apart from the circuit board 370. When the resistor is mounted, a gap 371 is generated between the second dielectric 340b and the circuit board 370.

[0063] Solderable terminals 360a and 360b may be individually attached to side ends of resistor 300, and resistor 300 may be soldered to circuit board 370. Solderable terminals 360a and 360b preferably have portions that extend at least partially along bottom surfaces 352a and 352b of electrode layers 350a and 350b.

[0064] The use of electrode layers 350a and 350b closest to the circuit board 370 helps to form a strong joint during solder reflow and to center the resistor 300 on the PCB pads 375a and 375b. The resistor 300 is mounted to the printed circuit board 370 using solder connections 380a and 380b between the solderable terminals 360a, 360b and corresponding solder pads 375a, 375b on the circuit board 170.

[0065] The heat dissipation elements 310a and 310b are coupled to the resistive element 320 by adhesive 330. The heat dissipation elements 310a and 310b may be thermally and / or mechanically and / or electrically coupled / connected to the resistive element 320 or may be adhered, bonded or mounted by other means. Solderable terminals 360a and 360b provide thermal and electrical connectivity between the resistive element 320 and the heat dissipation elements 310a, 310b. The thermal, electrical and / or mechanical coupling / connection between the resistive element 320 and the respective side ends of the heat dissipation elements 310a, 310b allows the heat dissipation elements 310a, 310b to be used as structural members of the resistor 300 and as heat spreaders.

[0066] Using heat dissipation elements 210a and 210b as the structural material of resistor 200 and heat dissipation elements 310a and 310b as the structural material of resistor 300 allows resistive elements 220 and 320 to be thinner than freestanding resistive elements, and resistors 200 and 300 to have resistance values ​​of about 1 mΩ to 30Ω using foil thicknesses of about 0.015 inches to about 0.001 inches. In addition to providing support for resistive elements 220 and 320, the efficient use of heat dissipation elements 210a, 210b and 310a, 310b as heat spreaders allows resistors 200 and 300 to effectively dissipate heat, resulting in a higher power rating than resistors that do not use a heat spreader. For example, a typical power rating for a 2512 size metal strip resistor is 1 W. Using the embodiments described herein, a 2512 size metal strip resistor can have a power rating of 3 W.

[0067] Additionally, the use of resistors 200 and 300 reduces or eliminates the risk of resistor failure due to thermal coefficient of expansion (TCE).

[0068] Based on modeling, it is believed that approximately 20% to approximately 50% of the heat generated during use of resistors 200 and 300 flows to heat dissipation elements 210a, 210b, 310a and 310b, thereby dissipating heat. Based on modeling, it is believed that heat dissipation elements 210a, 210b, 310a and 310b will not contain any or very little of the current flowing through resistors 200 and 300, and that the current flowing through heat dissipation elements 210a, 210b, 310a and 310b will be zero or close to zero during use. It is expected that all or nearly all of the current will flow through electrode layers 250a, 250b, 350a and 350b, and through resistive elements 220 and 320.

[0069] FIG. 4A is a top view of resistor 400, with each layer partially transparent for illustrative purposes. Resistor 400 may have a swage 409, and its overall configuration is similar to that described with reference to FIGS. 2A-2H or 3A-3B. Since resistor 400 is similar to resistor 200 or resistor 300, the description of resistor 200 or resistor 300 is incorporated herein by reference. FIG. 4A is a top view of resistor 400 in a transparent manner, showing heat dissipation element 410 (similar to heat dissipation element 210a, 210b or 310a, 310b described above), resistive element 420 (similar to resistive element 220 or 320 described above), and dielectric 440 (similar to dielectric 240a, 240b or 340a, 340b described above). Resistive element 420 has a substantially uniform surface area. As can be seen from FIG. 4A, the width of heat dissipation element 410 is approximately 2 to 4% wider than the width of resistance element 420.

[0070] 4B is a side view of resistor 400 with layers partially see-through for illustrative purposes. As shown in close-up 401 of a top corner of resistor 400, heat dissipation element 410 may be covered by solderable element 460. Swages 409 may be provided at the top and outer corners of heat dissipation element 410 and corresponding solderable element 460.

[0071] 4C is a bottom view of resistor 400, with layers partially see-through for illustrative purposes. A close-up 402 of resistor 400 details a central portion of resistor 400, showing resistive element 420, heat dissipation element 410, dielectric 440 covering the exterior of conductive element 410, and resistive element 420.

[0072] 4D is an isometric view of resistor 400 with cut-away portions for illustrative purposes. Heat dissipation element 410 can be thermally bonded to resistive element 420 by adhesive 430 (similar to adhesive 230 or 330) formed on the top surface of resistive element 420. An electrode layer 450 (similar to electrodes 250a, 250b or 350a, 350b) can be attached to the bottom surface of resistive element 420 as shown.

[0073] FIG. 5A is a top view of resistor 500 with layers partially transparent for illustrative purposes. Resistor 500 may have swage 509, and the overall configuration is as described with reference to FIGS. 2A-2H or 3A and 3B. Resistor 500 is similar to resistor 200 or resistor 300, and therefore the description of resistor 200 or resistor 300 is incorporated herein by reference. FIG. 5A is a top view of resistor 500 with transparency, showing heat dissipation element 510 (similar to heat dissipation element 210a, 210b or 310a, 310b described above), resistive element 520 (similar to resistive element 220 or 320 described above), and dielectric 540 (similar to dielectric 240a, 240b or 340a, 340b described above).

[0074] The resistive element 520 can be calibrated, for example, by thinning it to a desired thickness or by manipulating the current path by cutting the resistive element 520 at specific locations based on the target resistance value of the resistor 500. The patterning can be performed by chemical etching and / or laser etching. The resistive element 520 can be etched to form two grooves 504 under each of the heat dissipation elements 510. A dielectric material 540 fills the grooves 504. As can be seen from FIG. 5A, the width of the heat dissipation element 510 is about 2-4% larger than the width of the resistive element 520.

[0075] 5B is a side view of resistor 500, with layers partially see-through for illustrative purposes. As shown in close-up 501, which shows a top corner of resistor 500, heat dissipation element 510 can be covered by solderable element 560. Swages 509 can be provided at the top and outer corners of heat dissipation element 510 and corresponding solderable element 560.

[0076] 5C is a bottom view of resistor 500, with layers partially see-through for illustrative purposes. Enlarged view 502 details a central portion of resistor 500, showing resistive element 520, heat dissipation element 510, and dielectric 540 that covers the outer portions of conductive element 510 and resistive element 520.

[0077] 5D is an isometric view of resistor 500 with cut-away portions for illustrative purposes. Heat dissipation element 510 and resistive element 520 can be thermally bonded together by adhesive 530 (similar to adhesive 230 or 330) formed on the top surface of resistive element 520. An electrode layer 550 (similar to electrodes 250a, 250b or 350a, 350b) can be attached to the bottom surface of resistive element 520 as shown.

[0078] FIG. 6A is a top view of resistor 600, with each layer partially transparent for illustrative purposes. Resistor 600 may have a swage 609, and its overall configuration is similar to that described with reference to FIGS. 2A-2H or 3A-3B. Since resistor 600 is similar to resistor 200 or resistor 300, the description of resistor 200 or resistor 300 is incorporated herein by reference. FIG. 6A is a transparent top view of resistor 600, showing heat dissipation element 610 (similar to heat dissipation element 210a, 210b or 310a, 310b described above), resistive element 620 (similar to resistive element 220 or 320 described above), and dielectric 640 (similar to dielectric 240a, 240b or 340a, 340b described above).

[0079] The resistive element 620 can be calibrated, for example, by thinning it to a desired thickness or by manipulating the current path by cutting the resistive element 620 at specific locations based on the target resistance value of the resistor 600. The patterning can be performed by chemical etching and / or laser etching. The resistive element 620 can be etched to form two grooves 504 under each of the heat dissipation elements 610. A dielectric material 640 fills the grooves 604. As can be seen from FIG. 6A, the width of the heat dissipation element 610 is about 2-4% larger than the width of the resistive element 620.

[0080] 6B is a side view of resistor 600, with layers partially see-through for illustrative purposes. As shown in close-up 601, which shows a top corner of resistor 600, heat dissipation element 610 may be covered by solderable element 660. Swages 609 may be provided at the top and outer corners of heat dissipation element 610 and corresponding solderable element 660.

[0081] 6C is a bottom view of resistor 600, with layers partially see-through for illustrative purposes. Enlarged view 602 details a central portion of resistor 600, showing resistive element 620, heat dissipation element 610, and dielectric 640 that covers the outer portions of conductive element 610 and resistive element 620.

[0082] 6D is an isometric view of resistor 600 with cut-away portions for illustrative purposes. Heat dissipation element 610 and resistive element 620 may be thermally bonded together by adhesive 630 (similar to adhesive 230 or 330) formed on the top surface of resistive element 620. An electrode layer 650 (similar to electrodes 250a, 250b or 350a, 350b) may be attached to the bottom surface of resistive element 620 as shown.

[0083] FIG. 7 is a flow diagram illustrating an exemplary method for fabricating a resistor of the present invention. For example, resistor 200 will be used to illustrate the embodiment of the method shown in FIG. 7. In this embodiment of the method, the conductive layer(s) and resistive element 220 that will form the heat dissipation element may be, for example, cleaned and cut to a desired sheet size (705). The conductive layer(s) and resistive element 220 are laminated (710) using an adhesive. An electrode layer is plated (715) onto a portion of the bottom surface of resistive element 220 using known plating methods. The conductive layer is masked and patterned to separate the conductors into individual heat dissipation elements. In one embodiment, the resistive element is patterned, for example, using chemical etching, and / or thinned, for example, using a laser, to obtain a target resistance value. A dielectric is deposited, coated, or applied (720) to the top and bottom surfaces of resistor 200 to insulate the multiple conductive layers that form the heat dissipation element from each other. Optionally, a portion of the thermal dissipation element is compressed (725) to form a swage, as described with reference to Figures 2A-2H and 3A-3B. The compressive force causes the adhesive layer to compress (725) a portion of the thermal dissipation element to form a swage. The compression causes the adhesive layer to compress and / or the adhesive layer and the bottom of the thermal dissipation element to bend downward at the edges toward the resistive element.

[0084] A resistive element (heat sink element) having one or more conductive layers can be plated (730) with a solderable layer or terminal to electrically couple the resistive element to the conductive layers (heat sink element).

[0085] In any of the embodiments described herein, the adhesive can be cut during singulation, eliminating the need for a secondary laser process to remove the adhesive, such as Kapton, allowing the resistive element to be exposed prior to plating.

[0086] Although features and elements of the invention have been described in specific combinations in the embodiments, each feature can be used alone and other features and elements of the embodiments may be combined in various ways with the features and elements of the invention, or not. [Explanation of symbols]

[0087] 100, 200, 300, 400, 500, 600: Resistor 110a, 210a, 310a: first heat dissipation element 110b, 210b, 310b: second heat dissipation element 120, 220, 320, 420, 520, 620: Resistance elements 122, 222, 322, 115a, 115b, 215a, 215b, 216a, 216b, 315a, 315b, 316a, 316b: Top surface 124, 224, 324, 152a, 152b, 252a, 252b, 352a, 352b: Bottom 130, 230, 330, 430, 630: Adhesives, adhesives 140, 340, 440, 540, 640: Dielectric 140a, 240a, 340a: first dielectric 140b, 240b, 340b: second dielectric 150a, 250a, 350a: 1st electrode layer 150b, 250b, 350b: 2nd electrode layer 160a, 260a, 360a: first solderable terminal 160b, 260b, 360b: second solderable terminal 165a, 165b, 265a, 265b: Side edge 170, 270, 370: Circuit board 175a, 175b, 275a, 275b, 375a, 375b: solder pads 180a, 180b, 280a, 280b, 380a, 380b: solder joints 190, 271, 290, 371, 390: gap 201, 301: Area 209a, 209b, 309a, 309b, 409, 509, 609: Swage 410, 510, 610: Heat dissipation element 260a, 260b, 460, 560, 660: Solderable elements 292a, 292b, 391a, 391b: Length 302: Extension part 401, 402, 601: Enlarged view 450, 550, 650: Electrode layer 504: Groove AH1, AH2, H1, H2, SH1, SH2, SH3, SH4: Height W, W2, W3: Width

Claims

1. A resistor having a first side portion and a second side portion opposing the first side portion, the resistor having a top portion and a bottom portion opposing the top portion, a resistive element having a top surface facing the top side of the resistor and a bottom surface facing the bottom side of the resistor, the resistive element having a first side adjacent to the first portion of the resistor, the resistive element having a second side opposite the first portion of the resistor and adjacent to the second portion of the resistor; a first heat dissipation element formed of a conductive material, a first side portion of the first heat dissipation element that corresponds to a lower surface of an outer portion thereof is adjacent to the first side portion of the resistive element and is bonded to the upper surface of the resistive element via an adhesive, and a second side portion extends from the first side portion and is located away from the first side portion, the first side portion of the first heat dissipation element forming a first curved portion that is curved toward the upper surface of the resistive element, a second heat dissipation element formed of a conductive material, an I-side portion corresponding to the lower surface of the outer portion of the second heat dissipation element is adjacent to the second side portion of the resistive element and is bonded to the upper surface of the resistive element via an adhesive, and an II-side portion extends from the I-side portion and is located away from the I-side portion, and the I-side portion of the second heat dissipation element forms a second curved portion curved toward the resistive element, Furthermore, there is a gap between the first heat dissipation element and the second heat dissipation element, Furthermore, the first heat dissipation element and the second heat dissipation element are configured to be located on an upper surface side of the resistance element opposite to a side facing a mounting surface of the resistor. A resistor characterized in that

2. 2. The resistor of claim 1, wherein the first side of the resistive element is curved in a region adjacent the first curved portion and the second side of the resistive element is curved in a region adjacent the second curved portion.

3. 2. The resistor of claim 1, wherein the first heat dissipation element has a stepped, angled or arcuate top and peripheral corner adjacent the first side of the resistive element, and the second heat dissipation element has a stepped, angled or arcuate top and peripheral corner adjacent the second side of the resistive element.

4. 2. The resistor of claim 1, further comprising a first electrode layer disposed along the bottom surface of the resistive element adjacent to the first side of the resistive element, and a second electrode layer disposed along the bottom surface of the resistive element adjacent to the second side of the resistive element.

5. The resistor of claim 4 , further comprising a dielectric covering a portion of an upper surface of the first heat dissipation element and a portion of an upper surface of the second heat dissipation element and filling the gap between the first heat dissipation element and the second heat dissipation element.

6. 6. The resistor of claim 5, further comprising a dielectric deposited on at least a portion of the bottom surface of the resistive element, a portion of the bottom surface of the first electrode layer, and a portion of the bottom surface of the second electrode layer.

7. a first conductive layer extending along a first side portion of the resistor, the first conductive layer being in thermal or electrical communication with the resistive element, the first electrode layer, and the first heat dissipation element; a second conductive layer extending along a second side portion of the resistor, the second conductive layer being in thermal or electrical conduction with the resistive element, the second electrode layer, and the second heat dissipation element; 7. The resistor of claim 6 having the following formula:

8. the first conductive layer covers at least a portion of a top surface of the first heat dissipation element and at least a portion of the bottom surface of the first electrode layer; The resistor of claim 7 , wherein the second conductive layer covers at least a portion of a top surface of the second heat dissipation element and at least a portion of the bottom surface of the second electrode layer.

9. 2. The resistor of claim 1, wherein the adhesive is compressed in an area adjacent the first side of the resistive element and the adhesive is compressed in an area adjacent the second side of the resistive element.

10. 2. The resistor of claim 1, wherein each of the top and outer corners of the first heat dissipation element and the top and outer corners of the second heat dissipation element has a swage that forms a step in at least a portion of each of the first and second heat dissipation elements.

11. A method of making a resistor, comprising: Providing a resistive element, a first heat dissipation element formed of a conductive material, the first heat dissipation element being attached adjacent to a first side of the resistive element via an adhesive; a second heat dissipation element formed of a conductive material, the second heat dissipation element being attached adjacent to a second side of the resistive element via an adhesive, the first heat dissipation element and the second heat dissipation element being separated by a gap; a first curved portion that bends a lower surface of the first heat dissipation element at a position away from the gap toward the resistance element is formed on the first heat dissipation element, a second curved portion that bends a lower surface of the second heat dissipation element at a position away from the gap toward the resistor element is formed on the second heat dissipation element, Furthermore, the first heat dissipation element and the second heat dissipation element are configured to be located on the upper surface side of the resistance element opposite to the side facing the mounting surface of the resistor. A method of manufacturing comprising the steps of:

12. 12. The method of claim 11, further comprising rounding a first side of the resistive element in a region adjacent the first curved portion and rounding a second side of the resistive element in a region adjacent the second curved portion.

13. forming the first heat dissipation element having stepped, angled or arcuate top and peripheral corners adjacent the first side of the resistive element; 12. The method of claim 11, wherein the second heat dissipation element is formed to have stepped, angled or arcuate top and peripheral corners adjacent the second side of the resistive element.

14. further forming a first electrode layer along a bottom surface of the resistive element adjacent the first side of the resistive element; The method of claim 11 , further comprising forming a second electrode layer along a bottom surface of the resistive element adjacent the second side of the resistive element.

15. The method of claim 14 , further comprising covering a portion of a top surface of the first heat dissipation element and a portion of a top surface of the second heat dissipation element with a dielectric, and filling the gap between the first heat dissipation element and the second heat dissipation element with the dielectric.

16. 16. The method of claim 15, further comprising depositing at least a portion of the bottom surface of the resistive element, a portion of a bottom surface of the first electrode layer, and a portion of a bottom surface of the second electrode layer with a dielectric.

17. a first conductive layer for thermally or electrically conducting the first heat dissipation element, the resistive element, and the first electrode layer, the first conductive layer being plated to extend along a first side portion of the resistor; 17. The method of claim 16, further comprising plating a second conductive layer that thermally or electrically conducts the second heat dissipation element, the resistive element, and the second electrode layer, the second conductive layer extending along a second side portion of the resistor.

18. the first conductive layer covers at least a portion of a top surface of the first heat dissipation element and at least a portion of the bottom surface of the first electrode layer; 20. The method of claim 17, wherein the second conductive layer covers at least a portion of a top surface of the second heat dissipation element and at least a portion of the bottom surface of the second electrode layer.

19. 12. The method of claim 11, further comprising compressing the compressed adhesive in an area adjacent the first side of the resistive element, and further compressing the adhesive in an area adjacent the second side of the resistive element.

20. 12. The method of claim 11, further comprising forming swages at top and outer circumferential corners of the first heat dissipation element, and further forming swages at top and outer circumferential corners of the second heat dissipation element, each comprising a swage that forms a step in at least a portion of each of the first and second heat dissipation elements.

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