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

The effects of high dose ion irradiation through an amorphous surface layer on single crystalline 6H-SiC at 500 degrees C are studied in detail. Mater ial swelling, subsequent densification, surface erosion and recrystallizati on are quantified. The results demonstrate that undisturbed epitaxial regro wth of an amorphous surface layer on (0001)-oriented 6H-SiC cannot be achie ved at this temperature by ion irradiation. The shift of the amorphous/crys talline interface observed by RBS/C analysis is a consequence of columnar r egrowth and surface erosion. The columnar growth starts inside the heavily damaged transition region between the amorphous surface layer and the singl e crystalline bulk material. It is stopped by random nucleation. Neither th e interface roughness nor the kind of impurity atoms influence the thicknes s of the columnar layer. (C) 1999 Elsevier Science S.A. All rights reserved .