Method and system for forming copper indium gallium sulfur selenide absorption layer and cadmium sulfide buffer layer under non-vacuum condition

Abstract

A method and a system for forming a copper indium gallium sulfur selenide (CIGSSe) absorption layer and a cadmium sulfide (CdS) buffer layer under non-vacuum condition is disclosed. A coating layer is formed on the back electrode layer on the substrate by mixing the slurry on the back electrode layer, and the coating layer formed on the back electrode layer is densified by a densification device after initially dried, and then a primary selenization/sulfurization reaction process is carried out to form a primary CIGSSe layer, and then a thermal process is carried out to improve the lattice match of the primary CIGSSe layer, and then an impurity cleaning process is carried out by using potassium cyanide or bromide to remove the impurities of cuprous selenide and copper sulfide, and then a rear-stage selenization/sulfurization reaction process is carried out to produce the required rear-stage CIGSSe absorption layer. Finally, a CdS buffer layer is formed on the CIGSSe absorption layer by a chemical bath deposition method.