Fracture properties of Silicon carbide thin films characterized by bulge test of long membranes

The mechanical properties and fracture behavior of silicon carbide (3C-SiC) thin films grown on silicon substrates were characterized using bulge testing combined with a refined load-deflection model for long rectangular membranes. Plane-strain modulus Eps, prestress s₀, and fracture strength s_max for 3C-SiC thin films with thickness of 0.40 mum and 1.42 mum were extracted. The Eps values of SiC are strongly dependent on grain orientation. The thicker SiC film presents lower s₀ than the thinner film due to stress relaxation. The s_max values decrease with increasing film thickness. The statistical analysis of the fracture strength data were achieved by Weibull distribution function and the fracture origins were predicted.