Copper indium gallium selenide (CIGS) thin films with composition controlled by co-sputtering

摘要

A method and apparatus for forming a thin film of a copper indium gallium selenide (CIGS)-type material are disclosed. The method includes providing first and second targets in a common sputtering chamber. The first target includes a source of CIGS material, such as an approximately stoichiometric polycrystalline CIGS material, and the second target includes a chalcogen, such as selenium, sulfur, tellurium, or a combination of these elements. The second target provides an excess of chalcogen in the chamber. This can compensate, at least in part, for the loss of chalcogen from the CIGS-source in the first target, resulting in a thin film with a controlled stoichiometry which provides effective light absorption when used in a solar cell.

主权项

1. A method for forming a film comprising:
providing first and second targets in a common sputtering chamber, the first target comprising a Cu—In—Ga—Se alloy and the second target comprising a chalcogen; co-sputtering the first and second targets towards a substrate to form a film comprising polycrystalline CIGS material on the substrate which incorporates chalcogen from the second target.