Abstract
When the specimen dimension shrunk down to micron or nano scale, some material properties change slightly. Thermal conductivity coefficient studied in this thesis is just one instance. In this thesis, first, we build up a thin-film thermal conductivity measurement system by using 3□ method, including lock- in amplifier, cancellation box, monitoring software (LabVIEW) and other peripheral instruments. In the measurement system, we can obtain the thermal conductivity of thin film quickly (less than 15 minutes) and accurately. Reliability of the system, we measure the thermal conductivity of silicon dioxide(SiO2) and silicon nitride(Si3N4) thin films, results show that the thermal conductivities are 0.83±0.31％(W/m-K) and 0.78±0.94％(W/m-K), respectively. They are very close to the literature values. The temperature-dependent of thin film thermal conductivities are also discussed in this thesis. We control the surface temperature of heating plate and external power supply. In the measurement process, the temperature stability of heating plate can be controlled less than 1℃. We also actually measure the temperature-dependent thermal conductivities of silicon dioxide and silicon nitride. Experimental results show that their thermal conductivities increase gradually with temperature rise. The trend of thermal conductivity is the same with literature proposed. Hence, we can get the thermal conductivity of thin film by 3□ measurement system rapidly, and we can know the temperature-dependent thermal conductivity by the measurement system and external heating stage.