Surface step model for micropipe formation in SiC

Silicon carbide (SiC) single crystals, a promising material for high power and high temperature semiconductor devices, have microscopic hollow defects , so-called "micropipes." Their formation mechanism is not satisfactorily c larified yet. In this paper, a surface step model for micropipe formation i n SiC single crystals is proposed, where the strong repulsive interaction b etween surface steps on the SiC(0 0 0 1) surface is a major driving force f or coalescing unit cell size screw dislocations. (C) 2001 Elsevier Science B.V. All rights reserved.