Investigation of design parameters of 1-dimensional thermal conductivity measurement system for shortening measurement time of thermal conductivity by steady-temperature-prediction-method(STPM)

Abstract

This paper describes a development of fast thermal conductivity measurement system based on 1-dimensional thermal conductivity measurement by steady state method. In order to avoid thermal problems around power devices with high heat dissipation density, a reduction of thermal contact resistance is strongly needed while maintaining electrical insulation performance. A novel thermal interface material (TIM), which has both high electrical insulation performance and high thermal conductivity has been developed. However, in order to optimize the composition of the TIMs, a lot of parameter survey has to be performed. In order to shorten the design period of the TIMs, an improvement of thermal conductivity measurement should be needed in order to shorten the measurement time. We are developing the fast thermal conductivity measurement method based on the 1 dimensional measurement method with the steady state method and Steady — Temperature — Prediction Method (STPM). In this method, the steady temperature at the steady state condition in the 1-dimensional measurement is predicted by the transient temperature history and thermal conductivity is calculated. We have clarified the effectiveness of STPM on the fast measurement of thermal conductivity. However, in order to achieve both shortening the measurement time and the accuracy of the measurement, an optimization of the design parameters around the measurement apparatus should be investigated. From these background, in this paper, we investigated transient heat transfer process around the 1-dimensional thermal conductivity measurement system while changing the design parameter of the apparatus. Then, the relationship between the design parameter and the measurement of thermal conductivity by STPM was evaluated.