Modification of the optoelectronic properties of reactively evaporated In6Se7 thin films by Sn doping for photovoltaic applications
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Sn doped In6Se7 thin films with 5 wt% and 10 wt% Sn are prepared on glass substrate using reactive evaporation technique. The samples are characterized by XRD, FESEM, XPS and UV–Vis–NIR Spectrophotometer. XRD result shows that the samples are polycrystalline with monoclinic structure. Presence of compressive strain and lattice space shrinkage is observed in 10 wt% Sn doped sample. A detailed study of the optical properties demonstrated that a blue shift of 0.02 eV in the optical band gap of 5 wt% Sn doped sample is due to Burstein–Moss effect. Band gap narrowing in 10 wt% Sn doped sample is explained in terms of defect induced static disorder. 5 wt% Sn doped sample exhibits lowest resistivity and improved photoconductivity compared to undoped sample. This enhancement in optoelectronic properties facilitates the use of such films in photovoltaic applications.
Anuroop R would like to thank University Grants Commission (UGC), Govt. of India, for financial assistance in the form of Basic Scientific Research fellowship (UGC-BSR Fellowship).
- 14.K.G. Günther, in The use of thin films in physical investigations, ed. by B.J.C. Anderson (Academic press, London, 1966), p. 213Google Scholar
- 16.Powder Diffraction file, Joint Committe on Powder Diffraction Standards (JCPDS), JCPDS Card No: 24-0070Google Scholar
- 17.B.D. Cullity, in Elements of X-ray diffraction, ed. by M. Cohen (Addison-Wesley Publishing Company INC, Boston, 1978), p. 102Google Scholar
- 24.K.G. Saw, N.M. Aznan, F.K. Yam, S.S. Ng, S.Y. Pung, PLoS ONE 10, 1 (2015)Google Scholar
- 25.J.F. Moulder, W.F. Stickle, P.E. Sobol, K.D. Bomben, in Handbook of X-ray photoelectron spectroscopy: A reference book of standard spectra for identification and interpretation of XPS data, ed. by J. Chastain (Perkin-Elmer Corporation, Physical electronics division, Eden prairie, Minnesota, 1992), p. 224Google Scholar