Numerical simulation of direct current method of measuring thermal conductivities of thin films
直流法测试薄膜热导的数值模拟研究

Thermal conductivity is one of the most important physical properties of thin films.Different from two-or three-dimensional measurement structures in most reports,in this work,one-dimensional(1D) two-end supported cantilever beam is provided.The structure of cantilever includes a metal heater(which also serves as a thermometer) and thin film(s) underneath for measurement. 1D heat flow equation is employed to obtain the expression of temperature rise distribution(△T(x) along the cantilever beam and voltage drop changes along the heater(△U) when a direct current(DC) follows in the heater.To confirm the correctness of theoretical deduction,ANSYS finite element software is employed to simulate△T(x) and△U.Results demonstrate that the simulations are in good agreement with the theoretic calculations obtained from expressions of△T(x) and△U.Compared with conventional 3-times frequency(3ω) method,the DC method with 1D cantilever beam is relatively simple and accurate.