화학공학소재연구정보센터
Materials Science Forum, Vol.338-3, 185-188, 2000
4H-SiC substrate orientation effects on hydrogen etching and epitaxial growth
H-2 etching and epitaxial growth were performed on 4H-SiC (0001) substrates offcut 8 degrees towards either <1 (1) over bar 00 > or < 11 (2) over bar0 >. As-received surfaces possessed no discernable step structure. H-2 etched surfaces possessed step edges parallel to the offcut direction and step heights of typically 1-2 Si-C bilayers, although larger step heights were observed on both orientations using variable etch conditions. Epilayers were smooth regardless of the pre-growth H-2 etch used, provided there was minimal substrate polishing damage. No large-scale step bunching or rough growth was observed on epilayers grown on either orientation for thicknesses up to 15 mum. AFM revealed epilayer step heights of typically 1 and 2 Si-C bilayers, the largest step heights remaining within 5-6 bilayers for the thickest layers on both orientations.