Nature of the structural heterogeneity in SiH films by small angle neutron scattering

Abstract The density and small angle neutron scattering of a variety of silicon hydride films have been measured as function of heat treatment. Anode deposited samples have previously been shown to have a columnar morphology with a dominant column diameter of ∼60 A. This is confirmed and the new studies establish that the matrix separating the columns is of very low density - essentially comprising voids. The mechanism of hydrogen evolution during heat treatment depends on the void morphology. Both plasma deposited and sputtered films may be made which are structurally homogeneous on a scale of ≳ 10 A.