Size controlled synthesis of Ge nanocrystals in SiO2 at temperatures below 400 °C using magnetron sputtering

摘要

A simple and silicon process-compatible technique is reported for the synthesis of Ge nanocrystals (Ge-ncs) at low temperatures below 400 °C, which is much lower than the typical growth temperatures. The Ge-ncs were found to form only within a temperature window between 350 and 420 °C. The underlying mechanism has been explained by a competitive process between Volmer–Weber growth and oxidation reaction. We further implemented this technique in the fabrication of multilayered Ge-ncs which exhibited controllable crystallite size with high crystallization quality. The low temperature technique developed in this work would allow production of Ge-ncs and relative devices on low cost substrates, such as glass.