Influence of laser repetition rate on the Cu2ZnSn(SSe)4 thin films synthesized via pulsed laser deposition technique

Cu2ZnSn(SSe)4 (CZTSSe) thin films are considered as a viable source for the future electricity generation using solar energy. In this report, CZTSSe thin films were synthesized by pulsed laser deposition (PLD) technique as a function of laser pulse repetition rate onto the Mo coated glass substrates. Structural, surface morphological, optical and electrical properties of CZTSSe thin films have been investigated by X-ray diffraction (XRD), Raman spectroscopy, field emission scanning electron microscopy (FESEM), energy dispersive spectroscopy (EDX), X-ray photoelectron spectroscopy (XPS) and UV-vis spectroscopy. The XRD and Raman analysis confirmed the phase pure polycrystalline structure of thin films of CZTSSe synthesized at high pulse repetition rate. Moreover, the presence of the XRD peak at 27.72° corresponding to (112) plane reveals the tetragonal structure of CZTSSe. The band gap energy of synthesized CZTSSe thin films is found around 1.20 eV which is optimum for the solar energy harvesting. To the best of our knowledge, this is the first report on the deposition of CZTSSe via PLD technique by using different pulse repetition rate.