Measurement on thermal properties of solid films in electronic packages

A real-time holographic interferometry computer-aided-measurement system for measurement of the thermal properties of solid films has been established. The two principal problems of heat loss and edge reflection and their effects on measurement accuracy were analysed. With this new method, films commonly used in electronic packages, such as aluminium, copper, silicon, nickel, molybdenum, 63Sn/37Pb solder alloy, and FR-4, with various coefficients of thermal expansion ranging from 2.5 ppm//spl deg/C to 25 ppm//spl deg/C and thermal conductivities ranging from 0.2 W/m-K to 380 W/m-K, were measured. The experimental results show that this system has a high measurement accuracy and a wide measurement range for both coefficient of thermal expansion and thermal conductivity.