The influence of annealing atmosphere on the phase formation of Cu–Sn–S ternary compound by SILAR method

The influence of annealing atmosphere on the phase formation of Cu–Sn–S ternary compound by SILAR method was studied. Structural, optical and electrical properties of the compound were studied for the samples annealed at 420 °C for 1 h in different atmosphere. X-ray diffraction and Raman spectra showed that Cu2SnS3 cubic phase was obtained in an atmosphere of nitrogen and sulfur vapor mixture, while Cu4SnS4 orthorhombic phase was obtained in H2S atmosphere. An optical band-gap of 0.98 eV was obtained for Cu2SnS3 and 0.93 eV for Cu4SnS4 phase. The activation energies are about 0.1 eV for Cu2SnS3 phase and 0.06 eV for the Cu4SnS4 phase in high temperature region, but those are about 0.007 and 0.009 eV for them in low temperature region respectively.