Cu ( In 1−x Ga x ) Se 2 growth studies by in situ spectroscopic light scattering

Abstract
The growth of polycrystalline Cu(In1−xGax)Se2 thin films using a three-stage deposition process has been investigated by in situ diffuse spectroscopic light scattering in the wavelength range of 400–800 nm. Differences in the time dynamics of the intensity at different wavelengths can be explained by the development of surface roughness at different length scales. Of specific interest is the development of roughness around the stoichiometric points of film formation. It is shown that on-line monitoring of the spectroscopic light scattering can be used for process control and for adjustment of the final film roughness.