Investigation Regarding the Influence of Contact Condition on the Thermal Contact Resistance Between Copper and Indium

The thermal contact resistance caused by the rough contact interface accounts for a large proportion of the total thermal resistance of microelectronic devices. In this article, the influencing factors of the contact thermal resistance between copper-indium interface in electronic packaging has been investigated using numerical calculation methods. The Weierstrass-Mandelbrot fractal function was used to establish the copper-indium contact surface morphology with different surface characteristics. The temperature field of the copper-indium contact model with different surface roughness was calculated by the finite element method, and the influence of pressure on the contact thermal resistance was analyzed. The heat transfer behavior of the interface gap medium was simulated by setting the thermal contact conductivity that changed with the contact gap distance. The influence of air and grease in the thermal resistance of copper-indium contact was investigated. It was indicated that 1) pressure will rapidly reduce the contact thermal resistance, but the cost-effectiveness ratio gradually decreases and 2) influence of air on the contact thermal resistance decreases rapidly as the pressure increases, but grease has a significant effect under various pressure conditions.