On the Determination of Thermal Expansion Coefficient of Thermal Oxide

The accurate value of thermal expansion coefficient ( ) of thin film is an important thermal property in the design of microelectronic devices and microsystem. This research presents a microbridge buckling deformation caused by the residual stresses to determine the of thermal oxide (SiO2) film. The extraction of is supported through experimental means and finite element analysis (FEM) of the buckling profiles of microbridge. Moreover, in order to obtain the value of thermal SiO2 film in accuracy, the nanoindentation system and the optical microscope with high resolution gauge were used to determine the elastic modulus of thermal SiO2 film and the of silicon substrate, respectively. The combination of MEMS technologies and FEM with thermo-mechanical analysis approaches, the value of thermal SiO2 film was calculated. Measurement value presents for of thermal SiO2 film was 0.24 106/degree C with a standard deviation of 0.02 10-6/degree C.