Preparation of CulnSe(2) thin films by rapid thermal processing of Se-containing precursors

In this study, CuInSe2 thin films were prepared by the rapid thermal treatm ent (RTP) of metallic precursors in a close-spaced graphite container. The thermal diffusion process of selenium into the InSe/Cu/InSe precursor stack s critically influenced the structural properties (i.e., morphological feat ures, formation of crystalline phases and in-depth compositional uniformity ) of the films. In cases where pure elemental Se layers were incorporated i nto the stacks (i.e., InSe/Cu/InSe/Se), RTP treatment yielded compound film s with poor structural properties. Single-phase material with uniform and d ense surface morphologies was obtained when InSe/Cu/InSe precursors were re acted to an elemental Se atmosphere during RTP treatment. In these cases, s ingle Se pellets were placed in close proximity to the samples in a partial ly closed graphite container. The container was then rapidly heated in 1 mi n to 550 degrees C, followed by a reaction period of 6 min at this temperat ure. X-ray fluorescence (XRF) K-alpha 1,K-2 line intensity measurements fro m these specific samples, after different stages of etching, revealed a rel atively high degree of in-depth compositional uniformity. The deposition of this high quality material with a relatively simple and rapid two-stage te chnique represents an important technological advantage.