Thermal conductivity of thin films

Abstract

This thesis presents the evaluation of thermal conductivity of thin films of silicon dioxide on silicon substrate. The method used for measuring the thermal conductivity is named as 3 omega method which can operate within a temperature range of 20K to 320K. This method, first proposed by David G. Cahill [7] is a method where a metallic strip remained in close contact with the specimen surface. The details of 3 omega method will be described in the later chapter of this thesis.In this thesis, a mathematical modeling of 3 omega method is presented. The thermal conductivity of thin film was measured by 3 omega method. The data were taken from 20K to 120K. At temperatures of 20K, 30K, 50K and 80K the values of thermal conductivities of 0.14, 0.24, 0.35 and 0.55 W/m-K were obtained, respectively. At 90K, 100K, 110K, 120K the values of thermal conductivities of 0.62, 0.69, 0.77 and 0.84 W/m-K were obtained, respectively. The results show that the values obtained by 3 omega method match closely with the Cahilla??s [7] results within a temperature range of 20K to 120K.