Thermal Properties of Copper Tungsten with Copper Via Composite
This study focuses on a low-cost composite material based on CuW with Cu via, which functions as a more efficient thermal path for heat conduction. A 50mm X 50mm X 1mm CuW(15/85) speciman consists an array of 30X30 uniformly distributed cylindrical Cu via attaching to a microprocessor generating 100 watts power was studied.
By calculating the heat flux coming out of the top and the temperature difference along the thickness of the composite, we obtained the effective TC, which shows great dependence on the Cu via diameter. Larger Cu via diameter results in higher TC and CTE, which in turn creates wider gap between the CTEs of the composite and the microprocessor material causing higher thermal stress.