Post-annealing characteristics of in situ B-doped poly-SiGe films have been investigated. Thermal stability of substitutional B atoms at a supersaturated concentration was significantly improved by Ge doping, for example, the stability at 800°C for poly-Si0.6Ge0.4 films was nine times as high as that for poly-Si films. Both fast and slow processes exist for the deactivation of B. The fast process was due to movement of B atoms from substitutional to interstitial sites, enhanced by a local strain induced by the difference in atomic radii between Si and B atoms, and the slow process was due to trapping of B at grain boundaries during grain growth. The mechanism of the improved thermal stability of B atoms is discussed on the basis of local strain compensation by Ge atoms.
|Number of pages||4|
|Journal||Japanese Journal of Applied Physics, Part 1: Regular Papers and Short Notes and Review Papers|
|Issue number||4 B|
|Publication status||Published - Apr 1 2002|
All Science Journal Classification (ASJC) codes
- Physics and Astronomy(all)