Abstract：The Cu2ZnSnS4 thin film has advantages of naturally abundant elements and high absorption coefficient, which make it an ideal absorber material for thin film solar cell. The periodic metal precursors of Cu2ZnSnS4 were deposited by magnetron sputtering. Then, the Cu2ZnSnS4 thin films were fabricated by two-step sulfurization treatment of the periodic precursors. The effects of the first step sulfurization (pre-sulfurization) on the properties of Cu2ZnSnS4 thin films were studied. The results indicate that the pre-sulfurization treatment can promote the sulfurization reactions of periodic precursors. The crystallinities of Cu2ZnSnS4 thin films with pre-sulfurization are superior to that of Cu2ZnSnS4 thin film without pre-sulfurization. When the pre-sulfurization temperature is 350℃, the increase of pre-sulfurization time is beneficial to the sulfurization reactions of precursors and inhibition of Sn-loss. However, an overlong pre-sulfurization time leads to easy formations of secondary phases in the final thin films, which affect the properties of Cu2ZnSnS4 thin films. The pre-sulfurization temperature of 350℃ and pre-sulfurization time of 10 min can get the best crystallinity of Cu2ZnSnS4 thin film with Cu-poor and Zn-rich composition and void-free surface.
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