Abstract. We present a simple method to determine thermal conductivity coefficients (TCC) of conducting thin films using a compact micromachined test structure and common experimental apparatus. The test structure is fabricated by a sacrificial-layer surface micromachinmg technique with one mask process, and the measurements are performed using an optical microscope together with probe stages, a power supply and a heating stage, which are available in a laboratory. Analytical expressions are derived to calculate the thermal conductivity coefficients of thin films from the experimental data. Instead of conventional electrical methods that apply Joule-heating to the rising of a temperature gradient at a test structure and use polysilicon resistors as thermometer to monitor the temperature, our work proposes a temperature-displacement method to determine the temperature of test structure. Experimental results with a phosphorous-doped LPCVD polycrystalline silicon film are used to demonstrate the effectiveness of the proposed method. The obtained thermal conductivity coefficients show a small decrease as temperature increases, and its average value is around 39 Wm^-1?°C^-1 in the temperature range from room temperature to 400?°C.

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