Roughness of amorphous Zn-P thin films

The effect of thickness variation and the surface roughness of amorphous Zn 32P68 thin films has been investigated by the interference spectroscopy of the optical transmittance and reflectance, as well as by the atomic force m icroscopy (AFM). The analysis of the optical data allowed determination of the standard deviation of the thin film thickness by taking into account th e Gaussian distribution of the change in phase of radiation traversing a th in film. It appears that the value of the standard deviation of the film th ickness determined from the optical interference spectroscopy (sigma (w) ap proximate to 26 nm) is comparable with the value of the mean surface roughn ess (R-a approximate to 19 nm) evaluated from the AFM studies.