Crystallization and surface erosion of SiC by ion irradiation at 500°C

The effects of high dose ion irradiation through an amorphous surface layer on single crystalline 6H–SiC at 500°C are studied in detail. Material swelling, subsequent densification, surface erosion and recrystallization are quantified. The results demonstrate that undisturbed epitaxial regrowth of an amorphous surface layer on (0001)-oriented 6H–SiC cannot be achieved at this temperature by ion irradiation. The shift of the amorphous/crystalline interface observed by RBS/C analysis is a consequence of columnar regrowth and surface erosion. The columnar growth starts inside the heavily damaged transition region between the amorphous surface layer and the single crystalline bulk material. It is stopped by random nucleation. Neither the interface roughness nor the kind of impurity atoms influence the thickness of the columnar layer.