Hydrogen Migration In Phosphorous Doped Polycrystalline Silicon

Abstract

ABSTRACTHydrogen diffusion in phosphorous doped polycrystalline silicon was investigated by deuterium diffusion experiments. The presence of phosphorous enhances hydrogen diffusion. For high hydrogen concentrations the activation energy of the effective diffusion-coefficient amounts to 0.25-0.35 eV. At low hydrogen concentrations diffusion is governed by deep traps that are present in an appreciable concentration of 6×108 - 1019 cm−3. The hydrogen chemical-potential, 9H, decreases with increasing temperature at a rate of ˜ 0.002 eV/K. The data are discussed in terms of a two-level model used to describe hydrogen diffusion in amorphous and undoped polycrystalline silicon.