M. Albrecht et al., SURFACE RIPPLES, CROSSHATCH PATTERN, AND DISLOCATION FORMATION - COOPERATING MECHANISMS IN LATTICE MISMATCH RELAXATION, Applied physics letters, 67(9), 1995, pp. 1232-1234
We study the interplay of elastic and plastic strain relaxation of SiG
e/Si(001). We show that the formation of crosshatch patterns is the re
sult of a strain relaxation process that essentially consists of four
subsequent stages: (i) elastic strain relaxation by surface ripple for
mation; (ii) nucleation of dislocations at the rim of the substrate fo
llowed by dislocation glide and deposition of a misfit dislocation at
the interface; (iii) a locally enhanced growth rate at the strain rela
xed surface above the misfit dislocations that results in ridge format
ion. These ridges then form a crosshatch pattern that relax strain ela
stically. (iv) Preferred nucleation and multiplication of dislocations
in the troughs of the crosshatch pattern due to strain concentration.
The preferred formation of dislocations again results in locally enha
nced growth rates in the trough and thus leads to smoothing of the gro
wth surface. (C) 1995 American Institute of Physics.