Research on the Optoelectronic Properties of SnS Thin Films Prepared by Two-Stage Process

doi:10.7517/j.issn.1674-0475.2013.02.008

Abstract

Abstract: SnS thin films were prepared by two-stage process. Sn precursor layers were deposited on glass substrates by sputtering and followed by sulfurization of the metallic tin precursor layers at 220℃ in a furnace for 60 min. The characterization results of microstructures, composition and optical and electrical properties show that the SnS film presents p-type conductivity and has a (040) preferred grain orientation; SnS film has an orthorhombic structure, and the surface is uniform and density with the ratio of Sn to S close to 1. It is found that the film shows a high optical absorption coefficient of 5×10⁴ cm^-1 and persistent photoconductivity effect. It has a direct energy band gap of 1.23 eV. The prepared SnS film is useful as an absorption layer of solar cells and for fabrication of photo-sensitive device.

Key words: SnS films, two-stage process, solar cell, photoelectric properties

CLC Number:

TK514

JI Qiang, SHEN Hong-lie, JIANG Feng, WANG Wei, ZENG You-hong. Research on the Optoelectronic Properties of SnS Thin Films Prepared by Two-Stage Process[J]. Imaging Science and Photochemistry, 2013, 31(2): 150-156.

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