Wednesday, December 12, 2007

US Patent 7306823 - Coated copper/gallium nanoparticles for solar cells

Nanosolar is a developer of lower cost solar cell fabrication using printing technologies. This patent teaches using coated copper or gallium nanoparticle as a precursor material for copper indium/gallium diselenide (CIGS) solar cells as an alternative to oxide based particles which required reduction steps to be included in the fabrication. Claim 20 is representative.

20. A method for fabricating coated nanoparticles, comprising the steps of: obtaining core nanoparticles containing one or more elements from group IB and/or IIIA and/or VIA and coating the core nanoparticles with one or more layers of metal from group IB, IIIA or an element from group VIA in a controlled fashion such that the resulting coated nanoparticles have a desired stoichiometric ratio of elements, wherein the core nanoparticles include copper and gallium.