TWI407847B - Heat dissipating plate - Google Patents

Abstract

A heat dissipating plate is provided. The heat dissipating plate includes a substrate, a laminated insulation layer, a plurality of holes, and a heat conducting layer. The laminated insulation layer is disposed on the substrate and includes a plurality of stacked insulation layers. The plurality of holes penetrate through the laminated insulation layer and are filled with heat conducting material. The heat conducting layer is disposed on the laminated insulation layer.

Description

Heat sink substrate

The present invention relates to a heat dissipating substrate for use with electronic components. In particular, the present invention relates to a heat dissipating substrate for use with a light emitting diode.

In recent years, with the development of high-power light-emitting diode (LED) technology, its luminous efficiency has gradually increased to above 90~120lm/W. However, its electro-optic conversion efficiency is only about 15-20%. In other words, most of the input electrical energy is converted into thermal energy. If the thermal energy cannot be quickly led to the external environment, the temperature of the wafer will rise, which will affect the luminous intensity and life. Therefore, the thermal management of high-power LED products is receiving more and more attention.

In LED products, printed circuit boards are an indispensable part, providing support carriers for mounting and interconnecting electronic components, with heat-dissipating substrates as the main material. Generally, a metal substrate is generally used as a heat dissipation substrate in the industry. As shown in FIG. 1, the structure of the conventional heat dissipation substrate 80 includes a metal substrate 10, an insulating layer 30, and a copper foil layer 50. The largest thermal bottleneck of this type of substrate is the insulating layer 30 between the copper foil layer 50 and the metal substrate 10. Most of the insulating layer 30 uses epoxy resin as the main material, but because of its low heat transfer coefficient, it is necessary to separately add a heat conductive filler such as alumina, aluminum nitride and boron nitride to increase the heat transfer coefficient of the layer and thereby reduce The thermal impedance of the substrate. Even so, the thermal conductivity of the insulating layer 30 is still much lower than that of the metal material, so it is still the main bottleneck for heat dissipation of the heat dissipation substrate 80. In addition, when the content of the thermally conductive filler is too high, uneven dispersion or even delamination of the colloid may occur in the process, which affects the heat dissipation efficiency and mechanical properties of the layer.

The main object of the present invention is to provide a heat dissipating substrate with better heat dissipation effect.

Another object of the present invention is to provide a heat dissipating substrate having a relatively thin thickness.

The heat dissipation substrate of the present invention comprises a substrate, a laminated insulating layer, a plurality of holes, and a heat conductive layer. The laminated insulating layer is disposed on the substrate and includes a plurality of insulating layers disposed in a stacked manner. A plurality of holes penetrate the laminated insulating layer and are filled with a heat conductive material. The heat conductive layer is disposed on the laminated insulating layer.

The substrate may comprise a glass fiber resin, a metal or an alloy. The material of the plurality of insulating layers comprises a polyimide resin, an epoxy resin, an acrylic resin, a urethane resin, an organic resin, a polyparaxylene resin, and a bimaleimide (Bimaleimide). Resin, polyether ketone resin, unsaturated polyester resin, polyamide resin, urethane resin, phenol resin, polyether sulfone resin, polyethylene terephthalate or a mixture thereof. The thermal conductivity of the thermally conductive material is preferably greater than 10 W/mK and comprises metals, alloys, metals or non-metals and oxides thereof, metal-polymer composites, thermally conductive ruthenium resins or mixtures thereof. The metal may be silver, copper, aluminum, nickel or iron, and the alloy may be a tin-lead alloy, a tin-lead-silver alloy or a tin-silver-copper alloy. The metal or non-metal and its oxide may be alumina, boron nitride, aluminum nitride, tantalum carbide or carbon nanotubes. The laminated insulating layer has a thickness of less than 100 μm. The thermally conductive layer may comprise a metal or an alloy.

The plurality of holes may extend through the heat conducting layer and the laminated insulating layer, or may penetrate the insulating layer and the substrate, or penetrate the heat conducting layer, the laminated insulating layer, and the substrate. The heat dissipation substrate further includes a heat dissipation layer disposed under the substrate, and the heat dissipation layer is made of a metal or an alloy. A plurality of holes may penetrate the heat conducting layer, the laminated insulating layer, the substrate, and the heat dissipation layer. In various embodiments, the laminated insulating layer can be composed directly of polyimide.

As shown in the embodiment of FIG. 2, the heat dissipation substrate 800 of the present invention includes a substrate 100, a laminated insulating layer 300, a plurality of holes 400, and a heat conductive layer 500. The substrate 100 may comprise a glass fiber resin, a metal or an alloy. Specifically, the substrate 100 is used to carry an electronic component. Therefore, materials having good rigidity and hardness can be basically used for fabricating the substrate 100. The substrate 100 is preferably made of a metal or an alloy. Since such a material has good thermal conductivity, the heat dissipation effect of the heat dissipation substrate 800 as a whole can be further improved.

The laminated insulating layer 300 is disposed on the substrate 100 and includes a plurality of insulating layers 310 disposed in a stacked manner. The insulating layer 310 is made of a material having high electrical resistance, and is composed of a polyimide resin, an epoxy resin, an acrylic resin, a urethane resin, an organic resin, a polyparaxylene resin, and a double horse. a Bimaleimide resin, a polyether ketone resin, an unsaturated polyester resin, a polyamide resin, a polyurethane resin, a phenol resin, a polyether sulfone resin, a polyethylene terephthalate or a mixture thereof, It is preferably a polyimine resin. Wherein, each of the insulating layers 310 may be made of the same or different materials, that is, the adjacent insulating layers 310 may be sequentially stacked by the same or different materials. On the other hand, in the process, different insulating layers 310 using the same material can have different physical and chemical properties by controlling formation conditions such as ratio, temperature, time, and the like.

In the case of forming the laminated insulating layer 300 having the same total thickness, the laminated insulating layer 300 is formed by laminating a plurality of insulating layers 310 having a relatively small thickness as compared with the insulating layer 310 directly formed of a single thick thickness. The breakdown voltage. That is, if the laminated insulating layer 300 is composed of the insulating layers 310 which are laminated, even if the total thickness is thin, the breakdown voltage is not lower than the breakdown voltage of the laminated insulating layer 300 having a thick total thickness formed by the single insulating layer 310. In other words, if the laminated insulating layer 300 is composed of the insulating layers 310 which are laminated, if the laminated insulating layer 300 is formed by laminating a plurality of insulating layers 310, the thickness of the laminated insulating layer 300 can be reduced while still having a high collapse. Voltage. Thereby, the overall thickness of the heat dissipation substrate 800 can be further reduced. In a preferred embodiment, the laminated insulating layer 300 has a total thickness of less than 100 μm and a breakdown voltage of greater than 1 kV. On the other hand, the glass transition temperature of the laminated insulating layer 300 is preferably higher than 250 ° C, and the peel strength between the laminated insulating layer 300 and the substrate 100 is preferably more than 0.6 kgf / cm.

In the embodiment shown in FIG. 2, a plurality of holes 400 extend through the laminated insulating layer 300 and are filled with a thermally conductive material 410 therein. The thermal energy generated during operation of the electronic component 600 (see FIG. 3) can be conducted away from the thermally conductive layer 500 by the thermally conductive material 410 inside the hole 400, and further dissipated by the substrate 100 to the external environment. The position, the number, the inner diameter or the distribution manner of the hole 400 can be designed and configured according to the type, size, installation position, and coverage area of the electronic component 600. The thermal conductivity of the thermally conductive material is preferably greater than 10 W/mK and comprises metals, alloys, metals or non-metals and oxides thereof, metal-polymer composites, thermally conductive ruthenium resins or mixtures thereof. The metal may be silver, copper, aluminum, nickel or iron, and the alloy may be a tin-lead alloy, a tin-lead-silver alloy or a tin-silver-copper alloy. The metal or non-metal and its oxide may be alumina, boron nitride, aluminum nitride, tantalum carbide or carbon nanotubes. The laminated insulating layer has a thickness of less than 100 μm. The thermally conductive layer may comprise a metal or an alloy. The manner in which the heat conductive material is filled in the hole 400 may vary depending on the material properties thereof, for example, when the heat conductive resin heat conductive material is in a flowing state, it is poured into the hole 400, or the metal heat conductive material is plated in the hole 400, or mechanically The solid metal-polymer composite heat conductive material is pressed into the hole 400. The heat conductive material is not limited to filling the hole 400, and may be disposed to cover the sidewall of the hole 400. The laminated insulating layer has a thickness of less than 100 μm. The thermally conductive layer can comprise a metal or an alloy. The heat conductive layer 500 is disposed on the laminated insulating layer 300.

In various embodiments, the plurality of holes 400 may penetrate the heat conductive layer 500 and the laminated insulating layer 300 as shown in the design, or penetrate the laminated insulating layer 300 and the substrate 100, or penetrate the heat conductive layer 500, the laminated insulating layer 300, and the substrate 100. As shown in FIG. 3 , a plurality of holes 400 extend through the heat conducting layer 500 and the laminated insulating layer 300 , wherein the plurality of holes 400 are further disposed directly under the electronic component 600 . In particular, the heat generated by the electronic component 600 is conducted directly away from the thermally conductive material 410 in the lower aperture 400. At this time, since the heat conductive material 410 is not in contact with the heat conductive layer 500, both the heat conductive material 410 and the heat conductive layer 500 can use metal without a short circuit condition. As for other thermally conductive materials 410 having embodiments in contact with the thermally conductive layer 500, the thermally conductive material 410 may use materials that are not electrically conductive to avoid short circuits.

In the different embodiments shown in FIG. 4, a plurality of holes 400 extend through the laminated insulating layer 300 and the substrate 100. The heat dissipation substrate 800 further includes a heat dissipation layer 150 disposed under the substrate 100, that is, on the other side of the substrate 100 with respect to the laminated insulation layer 300. The heat dissipation layer 150 may comprise a metal or an alloy. Specifically, if a glass fiber resin is used as the material of the substrate 100, although the material has good hardness and rigidity, the heat dissipation property is inferior to that of the metal or the alloy, and the heat dissipation layer 150 may be further disposed at the time through the hole 400. The heat conducted by the heat conductive material 410 is dissipated to the external environment via the heat dissipation layer 150. In the different embodiments illustrated in FIG. 5, a plurality of holes 400 extend through the thermally conductive layer 500, the laminated insulating layer 300, and the substrate 100. Specifically, in different embodiments, the electronic component 600 can be disposed over the hole 400. The substrate 100 uses a fiberglass resin as a material, and the heat generated by the electronic component 600 is directly conducted by the heat conductive material 410 in the lower hole 400. The heat dissipation layer 150 is dispersed to the external environment via the heat dissipation layer 150. As shown in the preferred embodiment of FIG. 6, a plurality of holes 400 may extend through the thermally conductive layer 500, the laminated insulating layer 300, the substrate 100, and the heat dissipation layer 150. In the preferred embodiment, since the contact area of the heat conductive material 410 and the heat dissipation layer 150 is increased, that is, the area where the heat energy is conducted from the heat conductive material 410 to the heat dissipation layer 150 is increased, the heat dissipation efficiency of the heat dissipation substrate 800 can be further improved.

As shown in FIG. 7, in various embodiments, the laminated insulating layer 300 may be composed directly of polyimide. Specifically, the thickness of the insulating layer of the conventional heat-dissipating substrate must be greater than 1 mm to achieve a sufficiently high breakdown voltage, and polyimide is used as the material of the laminated insulating layer 300, and when the thickness is less than 100 μm, the insulating layer 300 is laminated. The breakdown voltage is still greater than 1kV. That is, the thickness of the laminated insulating layer 300 can be greatly reduced by using polyimide. In a different embodiment, as shown in FIG. 8 , a heat dissipation layer 150 may be further disposed on the other side of the substrate 100 relative to the polyimide layer 300 , wherein the plurality of holes 400 extend through the heat conduction layer 500 , the polyimide layer 300 , The substrate 100 and the heat dissipation layer 150.

While the foregoing description of the preferred embodiments of the invention, the embodiments of the invention The spirit and scope of the principles of the invention. Modifications of many forms, structures, arrangements, ratios, materials, components and components can be made by those skilled in the art to which the invention pertains. Therefore, the embodiments disclosed herein are to be considered as illustrative and not restrictive. The scope of the present invention is defined by the scope of the appended claims, and the legal equivalents thereof are not limited to the foregoing description.

10. . . Metal substrate

30. . . Insulation

50. . . Copper foil layer

80. . . Conventional heat sink substrate

100. . . Substrate

150. . . Heat sink

300. . . Laminated insulation

310. . . Insulation

400. . . Hole

410. . . Thermal material

500. . . Thermal layer

600. . . Electronic component

800. . . Heat sink substrate

Figure 1 is a schematic view of a conventional technique;

2 to 5 are schematic views of different embodiments of the present invention;

Figure 6 is a schematic view of a preferred embodiment of the present invention;

7 and 8 are schematic views of different embodiments of the present invention.

100. . . Substrate

150. . . Heat sink

300. . . Laminated insulation

310. . . Insulation

400. . . Hole

410. . . Thermal material

500. . . Thermal layer

800. . . Heat sink substrate

Claims (12)

A heat dissipating substrate comprising: a substrate; a laminated insulating layer disposed on the substrate, comprising a plurality of laminated insulating layers; a plurality of holes extending through the laminated insulating layer and filled with a heat conductive material; and a heat conducting A layer is disposed on the laminated insulating layer. The heat dissipating substrate according to claim 1, wherein the substrate comprises a glass fiber resin, a metal or an alloy. The heat dissipation substrate according to claim 1, wherein the material of the plurality of insulating layers comprises a polyimide resin, an epoxy resin, an acrylic resin, a urethane resin, an organic resin, and a polyparaxylene. Resin, Bimaleimide resin, polyether ketone resin, unsaturated polyester resin, polyamide resin, polyurethane resin, phenolic resin, polyether sulfone resin, polyethylene terephthalate Ester or a mixture thereof. The heat-dissipating substrate according to claim 1, wherein the heat-conducting material comprises a metal, an alloy, a metal or a non-metal and an oxide thereof, a metal-polymer composite material, a thermal conductive resin or a mixture thereof. The heat dissipation substrate according to claim 1, wherein the laminated insulating layer has a thickness of less than 100 μm. The heat dissipating substrate according to claim 1, wherein the heat conducting layer comprises a metal or an alloy. The heat dissipation substrate according to claim 1, wherein the plurality of holes penetrate the heat conduction layer and the laminated insulation layer. The heat dissipation substrate according to claim 1, wherein the plurality of holes penetrate the laminated insulating layer and the substrate. The heat dissipation substrate of claim 8, further comprising a heat dissipation layer disposed on the other side of the substrate relative to the laminated insulation layer, the heat dissipation layer being comprised of a metal or an alloy. The heat dissipation substrate according to claim 9, wherein the plurality of holes may penetrate the heat conduction layer, the laminated insulation layer, the substrate, and the heat dissipation layer. A heat dissipating substrate comprising: a substrate; a polyimide layer disposed on the substrate; a plurality of holes penetrating the polyimide layer and filled with a heat conductive material; and a heat conducting layer made of metal or The alloy is formed on the polyimide layer. The heat dissipation substrate of claim 11, further comprising a heat dissipation layer disposed on the other side of the substrate relative to the laminated insulation layer, the heat dissipation layer comprising a metal or an alloy, wherein the plurality of holes penetrate the heat conduction layer, a polyimide layer, the substrate, and the heat dissipation layer.