Amorphous silicon films with thicknesses ranging from about 20 Å to 2000 Å were evaporated onto silicon substrates. The surface and interfaces were then investigated by specular and diffuse x-ray scattering experiments in the region of total external reflection. A model of self-affine interfaces was used for the refinement. The rms roughness σ and the in-plane correlation length ξ vs film thickness follow power laws with exponents of $\beta =0.1\mathrm{}\pm 0.05$ and $1/z=0.6\pm 0.2,$ and the average Hurst parameter is $h=0.23\mathrm{}\pm \mathrm{0.05.}$ The resulting parameters are compatible with growth models based on the Kardar-Parisi-Zhang equation.

• Received 8 April 1996

DOI:https://doi.org/10.1103/PhysRevB.56.4085