Structure and properties of SnS thin layers obtained by sulfurization of electrodeposited tin precursors

Since current research trends in photovoltaics include among others low toxic and earth-abundant materials, tin sulfide (SnS) has high potential in device fabrication. We propose new inexpensive and well controllable method for manufacturing of tin sulfide layers by Sn electrodeposition and subsequent sulfurization in sulfur vapor in reusable reactor. Tin sulfide films crystallized in Herzenbergite orthorhombic structure beta-SnS were obtained at sulfurization temperature 330 degrees C. These films with thickness about 1-2 mu m are characterized by direct optical transitions, have high optical absorption coefficients and direct band gap 1.3 eV, so, they are promising for large-scale production of inexpensive and affordable solar cells. By a simple reducing the thickness of the Sn film precursors we can produce by this method desirable for the nanophotovoltaics very thin tin sulfide layers up to attached to the substrates SnS quantum dots with high visible optical absorption coefficients, which band structure can be modified and blue shifted to higher energy by the quantum confinement. (C) 2015 Elsevier Ltd. All rights reserved.