Photoelectrochemical, electrolyte electroreflectance and topological characterization of electrodeposited CuInSe2 films

n-Type CuInSe₂ thin films obtained by electrodeposition from a chloride bath containing SeO₂ and annealed at different temperatures in N₂ plus either 5% H₂ or a few parts per million O₂ were investigated to discover their photoelectrochemical and electrolyte electroreflectance behaviour. The fundamental parameters of the thin film-polysulphide electrolyte junction were determined and the performance and stability of the films were examined in photoelectrochemical cells. Finally, a point-by-point surface investigation with both a white light spot and a thin laser beam was performed, showing the non-uniform photoelectrochemical and electrolyte electroreflectance response of the films which could be related to inhomogeneous dopant distribution.