Surface roughness studies on 4H-SiC layers grown by liquid phase epitaxy

The surface roughness on 4H-SiC layers grown by LPE was systematically stud ied. The surface morphology was investigated by scanning electron microscop y and atomic force microscopy. Depending on the substrate orientation two d ifferent types of growth morphology were found: terraced and step flow grow th. The height of growth steps was found to depend on the angle of the subs trate off-orientation. The higher the degree of substrate off-orientation t he higher the step height. The terrace height depends on the impurity conce ntration in LPE layers. With the decrease of the impurity level, the terrac e height has been significantly decreased. (C) 2001 Elsevier Science B.V. A ll rights reserved.