We have investigated the oxidation behavior of poly-Si1-xGex films with 20%, 40 %, and 60 % Ge content in both dry and wet oxygen ambient. Poly-Si1-xGex films with various compositions and about 1000 Å in thickness were deposited on oxidized Si wafers (with 1000 Å thick thermal SiO2). Oxidation was carried out in a conventional tube furnace at 800 °C. The composition and thickness of the oxide were analyzed by RBS using rump simulation. The redistribution and chemical bonding of Si, Ge, and O elements were analyzed by XPS. The microstructure and phases formed in the films were analyzed by HR-TEM. In this study, it was found that Si was oxidized preferentially when the content of Ge in the alloy was low (20 %, 40 %). SiO2 was formed on the poly-Si1-xGex films, rejecting Ge and the oxidation rate of the poly-Si1-xGex films depends weakly on the Ge concentration. On the other hand, Si and Ge were oxidized simultaneously when the content of Ge was high (60 %). The formation of a mixed oxide layer on the poly-Si1-xGex films was observed. It was also found that oxide surface has a tendency to be flat from the initial oxidation stage due to the fast oxidation rate of Ge-rich films.
|Journal||Journal of the Korean Physical Society|
|Publication status||Published - 2003 Feb|
|Event||Proceedings of The 11th Seoul International Symposium on the Physics of Semiconductors and Apllications - 2002 - Cheju Island, Korea, Republic of|
Duration: 2002 Aug 20 → 2002 Aug 23
All Science Journal Classification (ASJC) codes
- Physics and Astronomy(all)