Investigations on the sulphur incorporation in sputtered Cu, In multilayer precursors

High quality CuInS2 layers have been grown using a two step process. Multiple Cu, In bilayers were deposited by RF magnetron sputtering on Mo-coated glass substrates followed by sulphurisation using elemental sulphur in a closed graphite box at different temperatures up to 5508C. The layers were characterised to study their structure and composition using XRD, SEM and EDAX. More sulphur was incorporated at lower annealing temperatures with sulphur content higher than 50 at.%, while the Cu/In ratio ranges between 0.9 to 1.1. As the annealing temperature increases beyond 4008C, the composition of sulphur decreases to 46 at.% with an incorporation of Mo in the layers. The secondary phases observed at different annealing temperatures were identi®ed and reported. Polycrystalline, single phase and densely packed CuInS2 layers with (1 1 2) preferred orientation were obtained for annealing temperatures of about 3508C. # 2001 Elsevier Science B.V. All rights reserved.