The paths of basal plane dislocations through 4H-SiC epitaxial layers grown on wafers with an 8° off-cut were tracked using ultra-violet photoluminescence imaging. The reduction of basal plane dislocations by conversion to threading edge dislocations was investigated at ex situ and in situ growth interrupts. For ex situ interrupts, basal plane dislocations were imaged after each of several growths. The wafer remained in the reactor for in situ interrupts and basal plane dislocations were imaged after the growth was finished. For in situ interrupts, a combination of temperature, propane flow, and duration was determined, which achieve a basal plane dislocation reduction of 98%.

Basal Plane Dislocation Reduction in 4H-SiC Epitaxy by Growth Interruptions. R.E.Stahlbush, B.L.VanMil, R.L.Myers-Ward, K.K.Lew, D.K.Gaskill, C.R.Edd: Applied Physics Letters, 2009, 94[4], 041916