Adsorption of Se, Na, and O on the Mo(110) surface: modeling atomic mechanisms at the back contact of thin film chalcopyrite solar cells

The deposition of the chalcopyrite light absorbers onto the back contact of thin films solar cells involves the adsorption of Se on Mo surfaces, to form an intermediate MoSe2 layer. Together with Se and the other elements composing the absorber, also impurities like oxygen and sodium are present in common processing technologies. In order to promote the understanding of atomic mechanisms and basic thermodynamic parameters related to deposition, we predict the adsorption energies and most stable adsorption sites of Se, O and Na on the Mo(110) surface using first principles calculations, based on density functional theory. We discuss implications for kinetics on the surface.