Effects of hydrogen annealing on heteroepitaxial-Ge layers on Si: Surface roughness and electrical quality

摘要: We have studied the effect of hydrogen annealing on surface roughness germanium (Ge) layers grown by chemical vapor deposition silicon using atomic force microscopy and cross-sectional high resolution scanning electron (HR-SEM). Our results indicate a strong reduction that approaches 90% at 825°C. The smoother Ge allowed for fabrication metal-oxide-semiconductor capacitors oxynitride (GeOxNy) as gate dielectric. Electrical quality was frequency capacitance–voltage characteristic epi-Ge showing negligible hysteresis. discuss in terms Ge–H cluster formation, which lowers diffusion barrier, allowing higher diffusivity mobility. temperature dependence shows tapering off temperatures exceeding 800°C, indicating barrier ∼92meV.