SiGe nanocrystal formation in PECVD grown SiOx/Si/Ge/Si/SiOx multilayers

Abstract

We have studied alternating gennanium-silicon-silicon oxide layers of 41 nm thickness grown on Si substrates by plasma enhanced chemically vapor deposition. The compositions of the grown films were detennined by X-ray photoelectron spectroscopy. The films were annealed at temperatures varying from 700 to 950 °C for 7.5 minutes under nitrogen atmosphere. High resolution cross section TEM images, electron diffraction and electron energy-loss spectroscopy as well as energy-dispersive X-ray analysis (EDAX) confinn presence of Ge nanocrystals in each layer. The effect of annealing on the Ge nanocrystal fonnation in multi layers was investigated by Raman spectroscopy and TEM.