Assembly of Ge nanocrystals on SiO2via a stress-induced dewetting process

We use epitaxial Ge islands on silicon-on-insulator (001) to initiate and drive the dewetting of the ultrathin (<8 nm) Si template layer. The process exposes the underlying SiO 2 layer and transforms the Ge islands into oxide-supported, electrically isolated, Ge-rich nanocrystals. We investigate the process of dewetting and demonstrate that it can be used for the controlled assembly of nanocrystals—from isolated single ones to dense arrays.