The Effect of Changing the Vapor Flux on Physical Properties of Nanocrystaline CdTe Thin Film, Prepared by Thermal Evaporation Method

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In the present investigation, seven Cadmium Telluride (CdTe) thin films with thickness of 350nm have been prepared by vacuum thermal evaporation technique. One of them was deposited by conventional vacuum thermal evaporation technique, while six others were deposited with applying a novel vapor flow controlling system. Placing this equipment in the way of vapor flux from the source to the substrate cut the depositing flux of vapor periodically and can change the way of vapor flux. It led to considerable change of optical properties, nanocrystalline structure, and also stochiometery of the thin films. All the samples showed nanocrystalline structure. A considerable increase in absorption coefficient was observed at 520nm wavelength of light, from 5.5 ×104 cm-1 for the sample prepared with conventional vacuum thermal evaporation technique to 9.8×104 cm-1 for a sample which prepared by applying mentioned equipment. The most considerable change in the bandgap, grain size and Te/Cd ratio were 1.54 eV to 1.66 eV, 40nm to 15nm, and 56/44 to 60/40 respectively. The optical parameters such as absorption coefficient, bandgap, refractive index, and structural parameters such as texture coefficient, preferential orientation factor and crystallite size of samples were obtained. Also EDAX and FESEM result of samples were compared with each other in this study.

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492-496

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November 2013

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© 2014 Trans Tech Publications Ltd. All Rights Reserved

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[1] M.A. Flores Mendoza, R. Castanedo Perez, G. Torres Delgado, J. Marquez Marin, Structural, morphological, optical and electrical properties of CdTe films deposited by CSS under an argon–oxygen mixture and vacuum, Sol. Energ. Mat. Sol. C. 95 (2011).

DOI: 10.1016/j.solmat.2010.07.023

Google Scholar

[2] M.H. Ehsani, H. RezagholipourDizaji, S. Azizi, S. F. GhavamiMirmahalle, F. HosseiniSiyanaki, Optical and structural properties of cadmium telluride films grown by glancing angle deposition, Phys. Scr. 88 (2013) 025602 (1-7).

DOI: 10.1088/0031-8949/88/02/025602

Google Scholar

[3] M. H. Ehsani, H. RezagholipourDizaji, M. H. Mirhaj, Patent No. 66339 Iran, (2010).

Google Scholar

[4] S. Lalitha, R. Sathyamoorthy, S. Senthilarasu, A. Subbarayan, K. Natarajan, Characterization of CdTe thin film dependence of structural and optical properties on temperature and thickness, Sol. Energ. Mat. Sol. C. 82 (2004) 187–199.

DOI: 10.1142/9789812704344_0049

Google Scholar

[5] S. Shanmugan, D. Mutharasu, Effect of Ar+ ion irradiation on structural and optical properties of e-beam evaporated cadmium telluride thin films, Mat. Sci. Semicon. Proc. 13 (2010) 298-302.

DOI: 10.1016/j.mssp.2010.12.007

Google Scholar

[6] S. K. Vajpai, R. Dube, M. Sharma, Studies on the mechanism of the structural evolution in Cu-Al-elemental powder mixture during high energy ball milling, J. Mater. Sci. 44 (2009)4334-4341.

DOI: 10.1007/s10853-009-3646-x

Google Scholar

[7] F. C. Akkari, M. Kanzari and B. Rezig, Growth and Properties of the CuInS2 Thin Films Produced by Glancing Angle Deposition, Mater. Sci. Eng C. 28 (2008) 692-696.

DOI: 10.1016/j.msec.2007.10.012

Google Scholar

[8] R. Swanepoel, Determination of the Thickness and Optical Constants of Amorphous Silicon, J. Phps. E: Sci. Instrum. 16 (1983)1214-1222.

DOI: 10.1088/0022-3735/16/12/023

Google Scholar

[9] N. Abbas Shah, A. Ali, Z. Ali, A. Maqsood , A. Aqili, Properties of Te-rich cadmium telluride thin films fabricated byclosedspace sublimation technique, J. Cryst. Growth 284 (2005) 477–485.

DOI: 10.1016/j.jcrysgro.2005.08.005

Google Scholar

[10] S. Kasap, P. Capper, Handbook of Electronic and Photonic Materials, Springer (2006).

Google Scholar

[11] G.K. Rao, K.V. Bangera, G.K. Shivakumar, Studies on vacuum deposited p-ZnTe/n-CdTe heterojunction diodes, Solid State Electron. 56 (2011) 100-103.

DOI: 10.1016/j.sse.2010.12.004

Google Scholar