Mechanical characterization of SiC film at high temperatures by tensile test

This paper reports the mechanical properties of silicon carbide (SiC) films at elevated temperatures up to 500degC. Poly-crystalline SiC film (poly-SiC) was deposited by LPCVD on a silicon wafer and patterned into a free-standing specimen on an "on-chip" tensile test device. The fracture strength of poly-SiC films showed little temperature dependence over the test temperature range. The tensile strength was 2.89 GPa at room temperature (RT), and decreased slightly to 2.66 GPa at 500degC. The fracture surface at 500degC showed almost the same morphology as that at RT, without any slippage. The potential of SiC films as a material for micromechanical devices working at high temperatures has been heretofore confirmed.