Patent ID: 8048477

Claim:
A method for forming a film of a group IB-IIIA-chalcogenide compound, comprising the steps of: forming a nanoparticle precursor material including group IB-chalcogenide and/or group IIIA-chalcogenide nanoparticles; disposing the nanoparticle precursor material and a source of extra chalcogen on a surface of a substrate; and heating the nanoparticle precursor material and source of extra chalcogen to a temperature sufficient to melt the extra chalcogen and to react the chalcogen with the group IB-chalcogenide nanoparticles and/or group IIIA chalcogenide nanoparticles to form a film of a group IB-IIIA-chalcogenide compound; wherein the nanoparticles include a chalcogenide core with a chalcogen-containing coating, whereby the coating provides the extra source of chalcogen.