Pseudomorphous Ge films with pyramid-like Ge islands have been deposited on
Si(001) substrate using molecular beam epitaxy at 300 degreesC. The island
s revealing quantum dots (QD) properties are self-organized during the grow
th in uniform Ge nanostructures with lateral sizes similar to 15 nm and hei
ght similar to 1.5 nm. Ge K XAFS measurements have been performed using tot
al electron yield detection mode. It was established that the presence of a
n appreciable exchange of atoms between the Si and Ge phases decreases the
elastic strains in the system during the deposition of the blocking Si Laye
r at 500 degreesC. It has been found that the Ge QD's are characterized by
interatomic Ge-Ge distances of 2.41 Angstrom, which is 0.04 Angstrom less t
han that in bulk Ge. (C) 2001 Elsevier Science B.V. All rights reserved.