Measurement of Interface Thermal Resistance of Micron-Thin Film by Dielectric Transient Current Method

Abstract

Multilayer dielectric stacking structure are widely used in various fields of electrical insulation applications to satisfy multiple thermal and electrical insulation requirements. The accurate information of thermal resistance between dielectric films is essential for effective thermal management of electrical equipment, which is helpful to obtain the internal temperature distribution of devices to ensure the operating stability. However, it will be difficult to obtain the accurate interface information by using the traditional method. In this work, a novel method is proposed to measure the thermal resistance between ultra-thin films based on dielectric transient current. A multilayer sample structure including a dielectric film sensor is utilized. The target interface thermal resistance between ultra-thin films was determined by analyzing the pyroelectric currents signal generated by dielectric film. Several group samples with different interfaces were prepared by changing the contact surface roughness and the thermal interface materials (TIM). The results show that the simulated pyroelectric current curve coincide with the experimental current curve, and the goodness of fit is more than 99%. The trend of the obtained data is consistent with the theoretical expectations.