Investigation of chip temperature related to various copper thickness on glass-fabric-based substrate

This paper presents an investigation of analyzing various thickness of “thermal functioned” copper layers on glass-fabric-based printed circuit board (PCB). To pursue the optimum thermal solution, two strategies are proposed for improving the heat dissipation ability on PCB and reducing copper amount usage. The first one is optimizing the thermal functioned copper layer position. By analyzing different locations of copper layer, top position attains the best heat dissipation efficiency. The other one is obtaining the best cross section profile of copper thickness. Different from common uniform copper thickness, a novel various copper thickness profile model is built for heat dissipation on PCB. By monitoring chip temperature, results show that the ability of heat dissipation is advanced by proposed various thickness of the thermal-function copper layer. Comparing to uniform copper layer thickness, the proposed various copper thickness profile efficiently cools down the 0.45-W power consuming chip by 2~5 degrees with the same copper amount usage. Results show that proposed various copper thickness profile owns both benefits of higher heat dissipation ability and lower copper usage.