Method for forming thin film chalcogenide layers

Abstract

The disclosed technology generally relates to chalcogenide thin films, and more particularly to ternary and quaternary chalcogenide thin films having a wide band-gap, and further relates to photovoltaic cells containing such thin films, e.g., as an absorber layer. In one aspect, a method of forming a ternary or quaternary thin film chalcogenide layer containing Cu and Si comprises depositing a copper layer on a substrate. The method additionally comprises depositing a silicon layer on the copper layer with a [Cu]/[Si] atomic ratio of at least 0.7, and thereafter annealing in an inert atmosphere. The method further includes performing a first selenization or a first sulfurization, thereby forming a ternary thin film chalcogenide layer on the substrate. In another aspect, a composite structure includes a substrate having a service temperature not exceeding 600° C. and a ternary chalcogenide thin film or a quaternary chalcogenide thin film on the substrate, where the ternary or quaternary chalcogenide thin film comprises a selenide and/or a sulfide containing Cu and Si.

Dependencies are inferred from the claim text.