This work describes a procedure to grow single phase Cu2ZnSnS4 (CZTS) thin films with tetragonal-kesterite type structure, through sequential evaporation of the elemental metallic precursors under a flux of sulphur supplied from an effusion cell. X-ray diffraction analysis (XRD) which is mostly used for the phase identification can not clearly distinguish the formation of secondary phases such as Cu2SnS3 (CTS), since both compounds have the same diffraction pattern; therefore the use of a complementary technique is needed. Raman scattering analysis was used to distinguish these phases.
The influence of the preparation conditions on the morphology and phases present in CZTS thin films were investigated through measurements of scanning electron microscopy (SEM) and XRD respectively. From transmittance measurements, the energy band gap of the CZTS films was estimated to be around 1.45 eV. The limitation of XRD to identify some of the phases that can remain after the growth process are investigate and the results of Raman analysis of the phases formed in samples grown by this method are presented. Further, the influence of the preparation conditions on the the chemical composition homogeneity in the volume was studied by X-ray photoelectron spectroscopy (XPS) analysis.
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