Combinatorial study of thin-film Cu2ZnSnS4 synthesis via metal precursor sulfurization

We report on studies related to the synthesis of thin-film Cu₂ZnSnS₄ via sulfurization of metal-precursor thin films. Combinatorially graded thin-film Cu-Zn-Sn library samples spanning various regions of the ternary Cu-Zn-Sn phase diagram were deposited at temperatures below 375 K and subsequently sulfurized in a high-vacuum system equipped with a sulfur valved-cracking source at temperatures from 600 K to 675 K. Comparisons of x-ray fluorescence and x-ray diffraction data from pre- and post-sulfurization films have revealed correlations between processing conditions, film composition, and the crystalline phases present. We have also performed cathodoluminescence and photoluminescence measurements and identified emission features consistent with the formation of the Cu₂ZnSnS₄.