Fracture property and quantitative strain evaluation of hetero-epitaxial single crystal 3C-SiC membrane

The following paper explores the development of a combined bulge test/micro-Raman analysis. This analysis, together with a refined load-deflection model (valid in both small and large deformation regimes, defined as the regimes in which the ratio between membrane deflection and width is smaller or larger than 1:10), allowed the determination of the elastic and optical properties of high quality single-crystal 3C-SiC squared membranes. Specifically we have evaluated the breaking strain of the membranes by measuring the breaking pressure for various membrane widths. The relation between the shift of the Raman Transverse Optical (TO) mode and the total residual strain (Δa/a) has been determined by measuring the TO shift for different membrane deflections. This relation, which allows determination of the residual strain by simply measuring the TO shift, was known only for thick samples (Olego et al) and high-oriented (100) thin films (Rohmfeld et al). Finally, we have calculated the TO stress-free value of high-quality thin single-crystal 3C-SiC/Si(100) films as 796.71 ± 0.04 cm−1.