Prediction of thermal contact resistance of uniform contact based on surface topography measurement

Abstract

For some high-power electronic devices such as ceramic resistors, generated heat is transferred to the housing of the electronic equipment through the contact surface, preventing excessive temperature rise of devices. In such cases, estimation of the thermal contact resistance (TCR) between the device and the housing is crucial, since it affects the temperature rise of devices. The TCR is often estimated by using an equation proposed by Tachibana and Sanokawa. The authors, in order to improve the prediction accuracy, have previously proposed a modified equation which includes the function with a diameter of a real contact point that expresses additional thermal resistance generated by a constriction and expansion of heat flow area. In this study, the TCR of uniform contact surface is estimated by giving the diameter of real contact point obtained by measurement surface topography to the modified equation. The obtained TCR is compared with the prediction results by Tachibana-Sanokawa's equation.