Growth and Characterization of Cu2znsns4 Thin Film by RF-Magnetron Sputtering
Polycrystalline Cu2ZnSnS4 (CZTS) thin film has been grown on glass substrate by RF-magnetron sputtering at substrate temperature 573 K using a commercial target of same composition. Structural and optical properties of the grown thin film have been investigated by X-ray diffraction (XRD), scanning electron microscope (SEM), Raman spectroscopy and UV-vis spectroscopy. Detailed analysis of XRD data has showed that the as-grown CZTS thin film has keserite structure ( I 4 , a = 5.4290 and c = 10.849Å) with preferred orientation along (112) plane. All the peaks observed in the XRD pattern have been accounted for kieserite structure, which shows the absence of additional phases such as elemental or binary or ternary systems in the grown film. SEM images recorded with different magnification have showed that the film has smooth and homogeneous surface with average crystallite size 100 nm. Raman spectrum recorded at room temperature has showed the dominant Raman shift at about 326 cm-1 which can be attributed to A1 mode and confirms the formation of kieserite CZTS phase. From optical transmittance spectrum, the grown film is found to have direct band gap of ~1.51 eV. The above observations show that the material under investigation is suitable for solar cell application.
V. Parthibaraj, K. Tamilarasan, K. S. Pugazhvadivu, C. Rangasami