Structural and electrical properties of Cu2Zn(Sn1−xSix)S4 (x = 0, x = 0.5) materials for photovoltaic applications

This work studied the electrical effects of the substitution of tin with silicon on p-type Cu2ZnSnS4 semiconductor compounds. To this purpose, two samples, namely Cu2ZnSnS4 and Cu2ZnSn0.5Si0.5S4, were prepared. The samples purities and homogeneities were characterized by both Energy Dispersive X-ray (EDX) spectroscopy and powder X-ray diffraction (PXRD).We observed that the temperature dependence of the electrical conductivity of materials exhibits a crossover from T−1/4 to T−1 dependence in the temperature range between 130 and 140 K. The characteristic temperature (T0,Mott), the hopping distance (Rhop), the average hopping energy (Δhop), the localization length (ξ) and the density of states (N(EF)), were determined, and their values were discussed within the models describing conductivity in p-type semiconductor.