Different and novel in-grown stacking faults were observed and characterized in

4H-SiC epitaxial layers grown on 4° or 8° off-cut substrates. Two different kinds

of triangular stacking faults were observed in the epilayers grown on 4° off-cut

substrates. The faults were formed during the epitaxial growth close to the episubstrate

interface and increased continuously in size during the growth. Their

structural and optical properties were however different as seen from both

synchrotron white beam topography and low temperature photoluminescence. The

luminescence spectra were similar but appeared in different energy regions of 2.85

to 2.95eV and 2.48 to 2.64eV, respectively, which have not been observed for previously reported stacking faults. A third stacking fault was observed in 8° offcut

as-grown epilayers, sometime with higher density. A combination of back

polishing, etching in molten KOH, and optical microscopy revealed the

geometrical structure of the stacking fault inside the epilayer. Also this fault started

close to the epi-substrate interface, expanded rapidly but changed geometry after

some time and reduced in size during further growth. The optical spectrum from

this fault was identical with the emission from the stacking faults previously only

observed and formed in bipolar diodes during forward voltage operation.

In-Grown Stacking Faults in 4H-SiC Epilayers Grown on Off-Cut Substrates.

J.Hassan, A.Henry, I.G.Ivanov, J.P.Bergman: Journal of Applied Physics, 2009,

105[12], 123513