Study of the junction and carrier lifetime properties of a spray-deposited CZTS thin-film solar cell

The Cu2ZnSnS4 (CZTS) thin-film solar cell fabricated entirely by a spray pyrolysis process was investigated under diffused white light in the present study. A CdS layer was developed as a heterojunction partner. The structural, morphological and photovoltaic characterization of an as-prepared stoichiometric CZTS film was carried out. The diode ideality factor n was found to be in the range of 1.2–5.6 in the forward bias region and it is explained by the Frenkel–Poole conduction model. The solar cell exhibited open-circuit voltage (Voc) of 157.25 mV, short-circuit current density (Jsc) of 3.024 mA cm−2 and fill factor (FF) of 24.77% at an incident irradiance of 200 W m−2 from the white LED source. The effective minority carrier lifetime of 263 μs was confirmed by the open-circuit voltage decay fitting under pulsed monochromatic LED excitation. (paper)