Enhancement of semiconducting photovoltaic absorbers by the addition of alkali salts through solution coating techniques

A method, comprising:

• depositing a conductive contact layer over a substrate suitable for use in a photovoltaic device;
• depositing a salt solution over the surface of the conductive contact layer, the solution comprising:
• a volatile solvent, and
• an alkali metal salt solute;
• and
• depositing a semiconducting absorber layer over the solution, wherein substantially all of the volatile solvent is evaporated before depositing the absorber layer thereby leaving a substantially uniform coating of the alkali metal salt over the surface of the conductive contact layer prior to depositing the absorber layer,
• wherein the volatile solvent evaporates in less than approximately 10 seconds thereby leaving a substantially uniform coating of the alkali metal salt over the surface of the conductive contact layer.