Effect of substrate temperature on the nucleation of glow discharge hydrogenated amorphous silicon

Abstract

The effect of substrate temperature (T_s) on the initial nucleation of hydrogenated amorphous silicon (a‐Si:H) prepared by glow discharge has been studied using an in situ ellipsometry probe. Evidence in the ellipsometry data for clustering of Si–Si bonds at nucleation centers, for films prepared with T_s ∼250 °C, gradually disappears as T_s is reduced below ∼200 °C. This indicates that the clustering process accompanies defect reduction during growth commonly observed in glow discharge a‐Si:H as T_s is increased. For T_s >200 °C, a sufficiently high surface mobility may enable the depositing species to bind at lower energy sites, thus explaining the observed results.