Thin film solar cells have the potential to significantly decrease the cost of photovoltaic technology. A highest efficiency of 20.3 % has been achieved for Cu(In,Ga)Se2 thin film solar cells technology [1]. However, large mass production is compromised by the scarcity of In and Ga. An attractive solution to this can be found in the kesterites, Cu2ZnSn(S,Se)4 (CZTSSe), which are composed of abundant elements, with absorption coefficient of over 104 cm-1 in the visible range and with a similar crystal structure to that of the chalcopyrites. Nevertheless, a narrow existence region of single phase kesterite has been predicted [2-3], smaller compared with chalcopyrites. A challenge for CZTSSe solar cells is the growth of single phase material because of the negative role of secondary phases. The highest efficiency reported to date, 10.1%, has been achieved for the mixed sulfide-selenide CZTSSe made by spin-coating particle-containing hydrazine solutions, followed by an atmospheric 540º C annealing [4]. Further improvements are necessary to achieve efficiencies comparable to Cu(In,Ga)Se2 solar cells. An enhanced efficiency would be expected by using physical vapour deposition techniques because a better quality material could be obtained. In this work, CZTS thin films are grown by flash evaporation followed by annealing in Ar atmosphere. Bulk materials, synthesized in our laboratory, are evaporated by flash at low substrate temperature of 100º C to produce the thin films. Thin films grown by using the CZTS bulk compound and ZnS, SnS and CuS binary compounds are compared. We investigate the influence of the bulk material composition on the final thin films. Moreover, the effect of the annealing treatment on the compositional, structural and morphological properties of the CZTS thin films is studied.