LAUSR

In this study, $$\text {Cu}_{2}\text {ZnSnS}_{4}$$Cu2ZnSnS4 (CZTS) thin films were grown on Mo-coated glass substrates by thermal evaporation of the precursor layers followed by annealing in a graphite box. The effect of annealing on the grain growth and morphology of the CZTS thin films was investigated at two different temperatures and $$\text {S}_{2}$$S2 partial pressures. X-ray diffraction and Raman spectroscopy analyses confirmed the formation of CZTS films with a kesterite structure with (112) preferred orientation. The grain growth was significantly enhanced by annealing the stacks at $$550\,^\circ {\text{C}}$$550∘C for 30 min at a $$\text {S}_{2}$$S2 partial pressure of $$1.2 \times 10^{4}\,\text{Pa}$$1.2×104Pa. The grain size was found to be in the range of $$1.0{-}2.0\,\upmu \text {m}$$1.0-2.0μm. The same grain size was obtained by carrying out the annealing at $$580\,^\circ {\text{C}}$$580∘C and a $$\text {S}_{2}$$S2 partial pressure of $$1.96 \times 10^{4}\,\text{Pa}$$1.96×104Pa just for 10 min. This grain size was much larger than the grain size of CZTS films obtained from annealing the stacks in two-zone tubular furnaces.