Cu2ZnSnS4 bulk crystals were synthesized by spark plasma sintering (SPS) method. The quantitative ratio of the Cu2ZnSnS4 phase was estimated at more than 98 vol.% by Rietveld method. The broad emission band peaked at about 1.25 eV observed in Photoluminescence spectra. This emission was disappeared after the sulfur annealing. At the same time, resistivity decreased and the carrier density increased. After the following annealing in vacuum, those values were returned again. The Hall mobility was quite low.
