It is shown that, under appropriate conditions, high-Ge-concentration coher
ent three-dimensional SiGe islands grown on Si(100) self-embed in a matrix
of a low-Ge-concentration alloy. The process may be more generally useful f
or preserving the shape of self-assembled "quantum dot" islands during embe
dding in a matrix material. (C) 1999 American Institute of Physics. [S0003-
6951(99)05104-9].