A kind of metal-coated graphite sheet and preparation method thereof

Abstract

The invention relates to the technical field of heat sinks, in particular to a metal-coated graphite sheet and a preparation method thereof. The preparation method comprises the following steps: plating chromium metal on the graphite sheet by magnetron sputtering; step 2, coating a copper alloy target The copper alloy on the material is plated on the chromium support layer of the first graphite sheet by the magnetron sputtering method; Step 3, the nickel metal is plated on the copper alloy shielding layer of the second graphite sheet by the magnetron sputtering method, Metallized graphite flakes are obtained. The beneficial effects of the present invention are: in the obtained metal-coated graphite sheet, the thermal conductivity of the plated alloy metal layer is stronger than that in the thickness direction of the graphite sheet, and compared with no copper plating or simple copper plating, it not only enhances the thermal conductivity of the graphite heat sink in the thickness direction Thermal conductivity in turn enhances electromagnetic shielding performance. Doping chromium in the copper alloy shielding layer improves the strength and electromagnetic shielding ability of the copper alloy, making it have good electrical and thermal conductivity, and making it have high hardness, crack resistance and softening temperature.

Description

technical field [0001] The invention relates to the technical field of heat sinks, in particular to a metal-coated graphite sheet and a preparation method thereof. Background technique [0002] As electronic products such as mobile phones gradually turn to the development trend of thinner and lighter, the power consumption of chips is increasing, and the heat dissipation problem of electronic products is becoming more and more prominent. In order to improve the heat dissipation of electronic products, graphite sheets are widely used in the design of electronic products. [0003] Graphite sheet is a kind of heat sink with very efficient heat conduction ability in the plane direction. When one end of the graphite sheet touches the heat source, the heat can be quickly and evenly transferred to the entire graphite sheet. However, the heat conduction and heat dissipation capabilities of the graphite sheet in the thickness direction are poor, and the heat cannot be dissipated in ...

AI Technical Summary

Problems solved by technology

Disadvantages: Because there is a layer of adhesive between the graphite sheet and the copper foil, this layer of adhesive has poor thermal conductivity, which is equivalent to a layer of heat insulation layer, so that the heat on the graphite sheet is difficult to transfer to the copper foil, which affects the heat dissipation effect

Due to the thin metal coating, the metal shielding effect is affected, and the shielding effectiveness is only about 70dB, which cannot meet the higher shielding requirements

②The metal of the metal shielding layer is more active and easily oxidized, which affects the shielding effect

③Regardless of vacuum evaporation or magnetron sputtering method of coating, no matter which method is used to vaporize the metal target metal, high temperature will be generated. At too high temperature, the PET film (plastic film) supporting the graphite sheet will soften, so that it cannot be rolled into batches Production

[0006] Further, the existing heat dissipation structure of graphite sheets on the motherboard of mobile phones is not conducive to the thin design of mobile phones

Images