Nucleation and growth of extended defects in silicon

摘要

The atomic-scale processes that lead to the nucleation and growth of extended defects depend on many factors. In this paper we review recent work in which we elucidated the pertinent processes for two different extrinsic extended defects, namely oxygen precipitates in the form of SiO_2 particles and hydrogen precipitates in the form of platelets. In both cases we trace the diffusing species, the nucleation of an initial point defect, and its gradual evolution into a defect complex and ultimately into macroscopic precipitates. In both cases, the growth process is accompanied by the emission of Si interstitials, but both the emission mechanism and the resulting atomic arrangements are radically different. The results on O precipitation lead to significant conclusions on the atomic-scale processes underlying thin-film oxidation of Si and the nature of point defects at the Si-SiO_2 interface. The results on H precipitation elucidate the mechanisms that underile the "smart cut" process for Si-On-Insulator (SOI) technology.