Abstract
Cu2ZnSnS4 thin films have been successfully deposited onto ultra clean glass substrates using spray pyrolysis technique. The characterizations of these films regarding structure, morphology, optical absorption and electrical transport were carried out using X-ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM), high-resolution TEM, Optical absorption spectroscopy and current–voltage measurements. XRD, TEM and HRTEM showed that the samples have a tetragonal structure and a polycrystalline nature with an average crystallite size of ∼3.4nm. SEM analysis reveals a compact surface morphology with slightly rough surface. Optical measurements showed a direct band gap of 1.56eV and absorption coefficient >104cm−1, which are optimal for low cost solar cells. The weak absorption below the band gap edge was observed and described by Urbach band tail rule. Dc electrical resistivity of films, in temperature range 10–300K, was found to arise due to variable range hopping conduction mechanism. Using the percolation theory and the diffusion model, the density of states near the Fermi level was calculated. Photoluminescence (PL) spectra exhibit the presence of broad emission band at 1.33eV.
Sign-in/Register to access full text options 
Free) 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
