Effects of SiH4, GeH4, and B 2 H 6 on the Nucleation and Deposition of Polycrystalline Si1 − x Ge x Films

Abstract

In this study, the effects of different reactants, namely, , and , on the nucleation and deposition of polycrystalline silicon‐germanium films on oxide surface in an ultrahigh vacuum chemical vapor deposition reactor were explored. The results show that the addition of tends to retard the nucleation process of poly films while is preferential for adsorbing on the oxide surface. These effects lead to different incubation duration depending on the kind of reactants used. On the deposition of films, it is observed that the Ge incorporation is only slightly related to the substrate type, but the deposition mode of films is much different from that of epitaxial growth on Si(100). The incorporation of Ge atoms also overcomes the anomalous doping effect encountered in heavily boron‐doped poly‐Si films and allows extremely low resistivity (below 2 mΩ‐cm) poly films to be obtained at low temperatures (≤550°C).