Evolution of Film Crystalline Structure During the Ultrafast Deposition of Crystalline Si Films

Abstract

ABSTRACTBy using a high density microwave plasma source, an ultrafast deposition rate over 1000 nm/s has been achieved for polycrystalline silicon (poly-Si) film deposition. We find that crystalline structure of the deposited film evolves along the film growth direction, i.e. large grains in surface region while small grains in the bottom region of the film. Systematic study of the deposition process has been performed as a function of the deposition duration. Based on the observed results, a possible mechanism, the annealing-assisted plasma-enhanced chemical vapor deposition, is proposed to describe the film growth process.