Heat conduction component and circuit board

Abstract

The utility model discloses a heat conduction component and a circuit board. Wherein the heat conduction component comprises a metal main body, at least one surface of the metal main body in the thickness direction is provided with metalized insulating ceramic, the insulating ceramic comprises a ceramic substrate and a metal film, the thickness of the ceramic substrate is smaller than that of the metal main body, and the metal film is arranged on the surface, facing and back to the metal main body, of the ceramic substrate. The circuit board includes a thermally conductive member disposed therein. According to the utility model, at least one surface of the metal main body is provided with the metalized insulating ceramic with relatively thin thickness to form the heat conduction part, and the heat conduction part has good heat conduction and insulation characteristics, and especially has more stable heat conduction performance.

Description

Technical Field

[0001] The utility model relates to the field of circuit boards; more specifically, to a heat-conducting component and a circuit board using the heat-conducting component. Background Art

[0002] To improve thermal conductivity, metal thermally conductive components, such as pure copper, can be incorporated into the circuit board. Pure copper offers excellent workability and a thermal conductivity of approximately 400 W / m·K, which decreases only slightly with increasing operating temperature, resulting in excellent thermal stability. However, because copper is a conductive material, the use of copper thermally conductive components prevents the creation of conductive structures, necessitating the use of a heat-isolating design for the circuit board. This also results in relatively poor voltage resistance.

[0003] Compared to metal thermally conductive components, using ceramic thermally conductive components with insulating properties can improve the voltage resistance of circuit boards and can also be equipped with conductive structures. However, the thermal conductivity of ceramic thermally conductive components decreases significantly with increasing operating temperature. For example, the thermal conductivity of aluminum nitride ceramics is approximately 170 W / m·K at room temperature, but decreases to approximately 150 W / m·K (a decrease of approximately 11.7%) as the operating temperature increases. This results in relatively poor thermal stability and a significant decrease in thermal conductivity at operating temperatures. Utility Model Content

[0004] In view of the deficiencies in the prior art, the main purpose of the present invention is to provide a heat-conducting component that has both heat-conducting and insulating properties and good heat-conducting stability.

[0005] Another object of the present invention is to provide a circuit board using the aforementioned heat-conducting component.

[0006] In order to achieve the above-mentioned main purpose, the first aspect of the present invention discloses a heat-conducting component, including a metal body, wherein the metal body is provided with a metallized insulating ceramic on one surface or two opposite surfaces in the thickness direction of the metal body, and the insulating ceramic includes a ceramic substrate and a metal film, wherein the ceramic substrate has a thickness smaller than that of the metal body, and the metal film is arranged on the surface of the ceramic substrate facing and facing away from the metal body.

[0007] Furthermore, the insulating ceramic and the metal body are connected via a metal sintered material.

[0008] Furthermore, the thickness of the metal sintered material is 0.1% to 30% of the overall thickness of the heat conducting component.

[0009] Furthermore, the material of the ceramic substrate is any one of aluminum nitride, aluminum oxide and silicon nitride ceramics.

[0010] Furthermore, the metal body is made of pure copper.

[0011] Furthermore, a copper foil layer is provided on the metal film on the side of the ceramic substrate away from the metal body.

[0012] Furthermore, when viewed along the thickness direction of the metal body, the insulating ceramic covers the surface of the metal body or has a distance from the surface edge of the metal body.

[0013] Furthermore, the thickness of the metal body is at least four times that of the ceramic substrate.

[0014] Furthermore, the thickness of the metal body is 0.6 mm to 2.0 mm, and the thickness of the ceramic substrate is 0.1 mm to 0.5 mm.

[0015] A second aspect of the present invention discloses a circuit board, wherein any one of the aforementioned heat-conducting components is provided in the circuit board.

[0016] The technical solution of the utility model has the following beneficial effects:

[0017] The heat-conducting component includes a metal body and an insulating ceramic with metallized surface, which has good thermal conductivity and insulation properties; the insulating ceramic includes a ceramic substrate and a metal film arranged on two opposite surfaces of the ceramic substrate to facilitate the reliable connection between the insulating ceramic and the metal body and the production of a copper foil layer on the insulating ceramic.

[0018] The thickness of the ceramic substrate is smaller than that of the metal body, so as to reduce the amount of ceramic with relatively poor thermal conductivity stability in the heat-conducting component, give full play to the advantage of high thermal conductivity stability of the metal body, and make the heat-conducting component as a whole have more stable thermal conductivity performance.

[0019] In order to more clearly illustrate the purpose, technical solutions and advantages of the present invention, the present invention is further described in detail below with reference to the accompanying drawings and specific implementation methods. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] Figure 1 is a schematic structural diagram of a first embodiment of a heat conducting component;

[0021] Figure 2 is a schematic structural diagram of a second embodiment of a heat conducting component;

[0022] Figure 3 is a schematic structural diagram of a third embodiment of a heat conducting component;

[0023] Figure 4 is a schematic structural diagram of a fourth embodiment of a heat conducting component;

[0024] Figure 5is a schematic structural diagram of a first embodiment of a circuit board;

[0025] Figure 6 2 is a schematic structural diagram of a second embodiment of a circuit board. DETAILED DESCRIPTION

[0026] In the following description, many specific details are explained in combination with specific embodiments to facilitate a full understanding of the present invention. However, it should be understood that the following embodiments and detailed descriptions are only for illustrative purposes and do not limit the scope of protection of the present invention.

[0027] Thermal Conductive Component Embodiment

[0028] like Figures 1 to 4 As shown, the thermally conductive component 100 of the embodiment includes a metal body 110, with a metallized insulating ceramic 120 provided on one or both surfaces of the metal body 110 in the thickness direction. The thickness direction of the metal body 110 refers to a direction perpendicular to the surface of the metal body 110 that is connected to the insulating ceramic 120, such as the vertical direction shown in the figure.

[0029] When viewed along the thickness direction of the metal body 110, the insulating ceramic 120 may cover the surface of the metal body 110 (eg, Figure 1 and Figure 2 ), and may also have a distance from the surface edge of the metal body 110 (such as Figure 3 There is no limitation on the shape of the metal body 110 ; for example, the projection shape of the metal body 110 in the thickness direction thereof may be circular or square.

[0030] In the embodiment, the heat-conducting component 100 includes a metal body 110 and an insulating ceramic 120, which has good thermal conductivity and insulation properties. A conductive structure can be provided on the insulating ceramic 120 to meet the different electrothermal structure design requirements of the circuit board. The material of the metal body 110 is preferably pure copper with a high thermal conductivity coefficient. The insulating ceramic 120 is a surface-metallized ceramic, including a ceramic substrate 121 and a metal film 122. The metal film 122 is provided on the surface of the ceramic substrate 121 facing and facing away from the metal body 110, so as to achieve a reliable connection between the insulating ceramic 120 and the metal body 110 and to form a copper foil layer on the insulating ceramic 120.

[0031] In the present invention, the material of the ceramic substrate 121 can be any one of aluminum nitride, aluminum oxide, and silicon nitride ceramics. The metal film 122 can be produced using PVD (Physical Vapor Deposition) technology, and its thickness is generally no greater than 5 μm, for example, 0.5 μm to 5 μm. The metal film 122 can be a single-layer metal film or a multi-layer metal film, for example, a multi-layer composite metal film including a titanium film and a copper film, with the titanium film disposed between the copper film and the ceramic substrate 121 to ensure good bonding between the metal film 122 and the ceramic substrate 121.

[0032] In this embodiment, the ceramic substrate 121 is thinner than the metal body 110 to reduce the amount of ceramic material (which has relatively poor thermal conductivity stability) used in the thermally conductive component 100. This allows the metal body 110 to take full advantage of its high thermal conductivity stability, resulting in more stable thermal conductivity for the thermally conductive component 100 as a whole. Preferably, the metal body 110 is at least four times thicker than the ceramic substrate 121. Exemplarily, the metal body 110 has a thickness of 0.6 mm to 2.0 mm, for example, approximately 1.1 mm; the ceramic substrate 121 has a thickness of 0.1 mm to 0.5 mm, for example, approximately 0.2 mm.

[0033] In an embodiment, the metal body 110 and the insulating ceramic 120 can be sintered together using a metal sintered material 130. The metal sintered material 130 can be a silver sintered material, particularly preferably a nanosilver sintered material. The thickness of the metal sintered material 130 can be 0.1% to 30% of the overall thickness of the thermally conductive component, preferably 0.5% to 10%, and more preferably 1% to 5%. The metal sintered material 130 connects the metal body 110 and the insulating ceramic 120, thereby improving bonding strength and reducing interfacial thermal resistance.

[0034] For example, a plurality of separated insulating ceramics 120 may be sintered onto a metal plate used to form the metal body 110, and then the metal plate may be cut into panels to form the thermally conductive component 100. As a variation of this embodiment, the metal body 110 and the insulating ceramic 120 may also be welded or bonded using a thermally conductive adhesive.

[0035] In one embodiment, the metal body 110 is made of pure copper with a thickness of 1.1 mm. The ceramic substrate 121 of the insulating ceramic 120 on both surfaces is made of aluminum nitride ceramic with a thickness of 0.2 mm. The metal sintered material 130 is a silver sintered material with a thickness of 0.05 mm and a thermal conductivity of 150 W / m·K. In this embodiment, the thermal conductivity of the thermally conductive component 100 is approximately 280 W / m·K at room temperature and approximately 260 W / m·K at operating temperature, a decrease of approximately 7.1%. Compared to aluminum nitride ceramic thermally conductive components, it has better thermal conductivity and thermal stability.

[0036] Furthermore, if Figure 4 As shown, in some embodiments, a copper foil layer 123 is provided on the metal film 122 on the side of the ceramic substrate 121 away from the metal body 110. The combined thickness of the metal film 122 and the copper foil layer 123 provided thereon can be approximately equal to the thickness of the outer copper foil on the outermost insulating core board used to make the circuit board substrate (details will be described later), thereby improving the thickness consistency of the circuit board surface. For example, the thickness of the copper foil layer 123 can be 20 μm to 80 μm.

[0037] Circuit board embodiment

[0038] like Figure 5 and Figure 6 As shown, the second embodiment of the present invention discloses a circuit board 200 provided with the aforementioned heat-conducting component 100. The circuit board 200 includes a substrate 210 and the heat-conducting component 100 disposed in the substrate 210. The heat-conducting component 100 is used to form a heat-conducting channel penetrating the substrate 210 in the thickness direction of the circuit board to facilitate rapid heat conduction.

[0039] Exemplarily, substrate 210 includes a single-layer or multi-layer, double-sided copper-clad insulating core board 211. Insulating core board 211 has an outer copper foil 211a and an inner copper foil 211b. The multiple insulating core boards 211 are connected by bonding sheets 212. Insulating core board 211 can be made of FR-4 or FR-15 copper-clad core board, and bonding sheet 212 can be made of prepreg, although this is not a limitation of the present invention. Inner conductive circuitry can be provided within substrate 210. For example, the inner copper foil 211b of insulating core board 211 can be etched to form the inner conductive circuitry.

[0040] The substrate 210 can be obtained by a hot pressing method commonly used in the field of circuit boards. Prior to hot pressing, through holes for placing the thermally conductive component 100 are pre-machined in the insulating core board 211 and the bonding sheet 212. During the hot pressing process, the resin in the bonding sheet 212 flows and fills the gaps in the through holes, thereby achieving a fixed connection between the thermally conductive component 100 and the substrate 210. Alternatively, the substrate 210 can be manufactured first, and then through holes can be machined in the substrate 210 and the thermally conductive component 100 can be placed therein. The gaps in the through holes can then be filled using a resin plugging method commonly used in the field of circuit boards. This can also achieve a fixed connection between the thermally conductive component 100 and the substrate 210.

[0041] After the thermally conductive component 100 is secured to the substrate 210, copper plating can be performed on both sides of the circuit board 200 to form a first surface copper foil layer 230a and a second surface copper foil layer 230b. Opposite sides of the thermally conductive component 100 are connected to the first surface copper foil layer 230a and the second surface copper foil layer 230b, respectively. Subsequently, a surface wiring layer 230 can be etched on at least one side of the circuit board 200 to form the surface wiring layer 230. The conductive traces of the surface wiring layer 230 can be disposed on the substrate 210 and the ceramic substrate 121.

[0042] In such Figure 5 In the first embodiment of the circuit board shown, the metal body 110 of the heat-conducting component 100 is provided with insulating ceramic 120 on both surfaces in the thickness direction thereof, but the insulating ceramic 120 is not provided with a copper foil layer 123. One side surface of the circuit board 200 (for example, the surface provided with the first surface copper foil layer 230a) has a surface wiring layer 230 provided on the substrate 210 and the ceramic substrate 121. The surface wiring layer 230 is obtained by etching the first surface copper foil layer 230a, the outer copper foil 211a, and the metal film 122 on this side surface; the second surface copper foil layer 230b on the other side surface of the circuit board 200 can be left unetched and can serve as a heat dissipation surface as a whole. As a variation of the first embodiment of the circuit board, the other side surface of the circuit board can also be etched to form a conductive circuit.

[0043] In such Figure 6 In the second embodiment of the circuit board shown, the metal body 110 is provided with an insulating ceramic 120 on one surface thereof in the thickness direction. Within the insulating ceramic 120, a copper foil layer 123 is provided on a metal film 122 on the side of the ceramic substrate 121 away from the metal body 110. The copper foil layer 123 is connected to a first surface copper foil layer 230a, and the metal body 110 is connected to a second surface copper foil layer 230b. The first surface copper foil layer 230a, the outer copper foil 211a, the copper foil layer 123, and the metal film 122 are etched to form a surface circuit layer 230. The combined thickness of the metal film 122 and the copper foil layer 123 is approximately equal to the thickness of the outer copper foil 211a on the insulating core board 211, thereby improving the thickness consistency of the surface circuit layer 230. The second surface copper foil layer 230b can be left unetched and function as a heat dissipation surface in its entirety.

[0044] It should be noted that for the sake of simplicity, some identical descriptions in the above different embodiments have been omitted. Unless there are any contradictions or exclusions, the different embodiments disclosed above can be referenced, referred to, or combined with each other, and the technical features / components of different embodiments can also be combined and / or replaced with each other.

[0045] Although the present invention has been disclosed above with reference to specific embodiments, these embodiments are not intended to limit the scope of the present invention. Any person skilled in the art may make modifications or substitutions without departing from the scope of the present invention. Any modifications made in accordance with the present invention shall be covered by the scope of protection of the present invention.

Claims

1. A heat-conducting component comprising a metal body; characterized in that: The metal body is provided with metallized insulating ceramic on one surface or two opposite surfaces in the thickness direction of the metal body, and the insulating ceramic includes a ceramic substrate and a metal film. The ceramic substrate has a thickness smaller than that of the metal body, and the metal film is provided on the surface of the ceramic substrate facing and facing away from the metal body.

2. The heat conducting component according to claim 1, wherein: The insulating ceramic and the metal body are connected via a metal sintered material.

3. The heat conducting component according to claim 2, wherein: The thickness of the metal sintered material is 0.1% to 30% of the overall thickness of the heat conducting component.

4. The heat conducting component according to claim 1, wherein: The material of the ceramic substrate is any one of aluminum nitride, aluminum oxide and silicon nitride ceramics.

5. The heat conducting component according to claim 1, wherein: The material of the metal body is pure copper.

6. The heat conducting component according to claim 1, wherein: A copper foil layer is provided on the metal film on the side of the ceramic substrate away from the metal body.

7. The heat conducting component according to claim 1, wherein: When viewed along the thickness direction of the metal body, the insulating ceramic covers the surface of the metal body or has a distance from the edge of the surface of the metal body.

8. The heat conducting component according to claim 1, wherein: The metal body is at least four times thicker than the ceramic substrate.

9. The heat conducting component according to claim 1, wherein: The thickness of the metal body is 0.6 mm to 2.0 mm, and the thickness of the ceramic substrate is 0.1 mm to 0.5 mm.

10. A circuit board, characterized in that: The circuit board is provided with the heat conducting component according to any one of claims 1 to 9.

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