Deposition of Polysilicon Films by Hot-Wire CVD at Low Temperatures for Photovoltaic Applications

Abstract

ABSTRACTPolysilicon (poly-Si) thin films have been obtained using hot-wire chemical vapor deposition (HWCVD) from silane-hydrogen mixtures. The films were prepared at low substrate temperatures (down to 200°C) and at very high deposition rates (up to 40 Å/s). They showed good crystalline properties and no amorphous phases were detected. The films can also be efficiently doped by adding diborane or phosphine to gas phase. In this paper, an overview of the properties of the poly-Si films, intrinsic and p and n-doped, deposited at our laboratory by HWCVD is presented and discussed. The properties of the material and the features of the deposition technique which are interesting for their application in photovoltaics are emphasized.