Structural perfection of silicon carbide crystals grown on profiled seeds by sublimation method

Abstract

The distribution of extended defects in silicon carbide (SiC) crystals grown on profiled seeds by the sublimation sandwich method (physical vapor transport) has been studied by optical microscopy in combination with chemical etching. It is established that free lateral overgrowth of protruding relief elements (mesas) is accompanied by a sharp decrease in the density of threading dislocations and micropores. The decreased density of dislocations is retained after growing a thick layer that involves the overgrowth of grooves that separated individual mesas.