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Comprehensive Investigation on the Nanovoid Heterogeneity in Mo Thin Films Used for Solar Cells Applications

Published online by Cambridge University Press:  04 June 2018

Hamda A. Al-Thani*
Affiliation:
National Energy and Water Research Center (NEWRC), POBOX54111, Abu Dhabi, UAE
Falah S. Hasoon
Affiliation:
National Energy and Water Research Center (NEWRC), POBOX54111, Abu Dhabi, UAE
*
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Abstract

The purpose of this research work is to gain a better understanding of the nanostructural properties of Molybdenum (Mo) thin films’ porosity, nanovoid heterogeneity and provide detailed quantitative data on voids volume fractions, sizes, shapes, and their preferred orientations as the growth sputtering pressure changes systematically. This knowledge shall assists in optimizing Mo film nano- and micro-structural properties as desired for solar cells applications. Therefore, two separate series of Mo thin films (∼ 0.7 μm thick) were deposited on high purity (99.999) Al-foil (10 μm thick), and Si/SiO2 substrates using direct-current (DC) planar magnetron sputtering. The sputtering pressure was varied from 0.8 mT to 12 mT, with a sputtering power density of 1.2 W/cm2. High-Resolution Scanning Electron Microscopy (HRSEM) was used to examine the Mo films’ morphology. Whereas, the Mo films’ bulk resistivity was calculated from the films’ thickness and average sheet resistance measurements using Dektak Surface Profilometer, and Four Point Probe method, respectively. Small Angle X-Ray Scattering (SAXS) technique was applied to examine the existence of nanovoids and its heterogeneity in the Mo-coated Al foils (Al/Mo). Moreover, the porosity of the Mo films as a function of sputtering pressure was studied by Transmission Electron Microscopy (TEM) on Mo-coated Si/SiO2 (Si/SiO2/Mo) substrates.

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Articles
Copyright
Copyright © Materials Research Society 2018 

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References

REFERENCES

Maoujoud, M., Kons, P., Offergeld, M.J., and Bouillon, F., Thin Solid Films 238, 62 (1994).CrossRefGoogle Scholar
Adams, D.P., Parfitt, L.J., Bilello, J.C., Yalisove, S.M., and Rek, Z.U., Thin Solid Films 266, 52 (1995).CrossRefGoogle Scholar
Granath, K., Rockett, A., Bodegard, M., Nender, C., and Stolt, L., 13th European Photovoltaic Solar Energy Conference, Nice, France, 1983 (1995).Google Scholar
Christian, J.W., “The Theory of Transformations in Metals and Alloys”, 2nd ed. (Pergamon Press, Oxford, 1975).Google Scholar
Thornton, J.A., Ann. Rev. Mater. Sci. 7, 239 (1977).CrossRefGoogle Scholar
Drüsedau, T.P., Klabunde, F., Veit, P., and Hempel, T., Phys. Stat. Sol. (a) 161, 167 (1997).Google Scholar
Vink, T.J., Somers, M.A.J., Daams, J.L.C., and Dirks, A.G., J. Appl. Phys. 70, 4301 (1991).CrossRefGoogle Scholar
Vink, T.J. and van Zon, J.B.D., J. Vac. Sci. Technol. A9, 124 (1991).CrossRefGoogle Scholar
Drusedau, T.P., Klabunde, F., Veit, P., and Hempel, T., Phys. Stat. Sol. 161, 167 (1997).3.0.CO;2-N>CrossRefGoogle Scholar
Thornton, J.A., Thin Solid Films 171, 5 (1989).CrossRefGoogle Scholar
Al-Thani, H.A., Hasoon, F.S., Young, M., Asher, S., Alleman, J.L., and Al-Jassim, M.M. and Williamson, D.L., 29th IEEE PVSC, 720-723 (2002).Google Scholar
Granath, K., Bodegard, M., and Stolt, L., Solar Energy Mat. Sol. Cells 60, 2000, p.279.CrossRefGoogle Scholar
Granata, J.E., “The Impact of Deliberate Sodium Incorporation on CuInSe2-Based Solar Cells”, Ph.D. Thesis, Dept. of Physics, University of Colorado, Colorado, USA, 1999.Google Scholar
Granata, J.E. and Sites, J.R., Proc. 2nd World Proc. 1st World Conf. on Photovolt. Energy Conv., 604 (1998)Google Scholar
Brewer, L., Lamoreux, R.H., Ferro, R., Marazza, R., and Girgis, K., “Molybdenum: Physico-chemical Properties of its Compounds and Alloys”, (International Atomic Energy Agency, Vienna, 1980).Google Scholar
Wada, T., 11th Int’l Conf. on Ternary and Multinary Compounds 8, 903 (1998).Google Scholar
Williamson, D.L., Mat. Res. Soc. Symp. Proc. 377, 251 (1995).CrossRefGoogle Scholar
Williamson, D.L., Solar Energy Mat. Solar Cells 78, 41 (2003).CrossRefGoogle Scholar
Williamson, D.L., Mahan, AH., Nelson, B.P., and Crandall, R.S., Appl. Phys. Lett. 55, 783 (1989).CrossRefGoogle Scholar
Kratky, O., “Small Angle X-ray Scattering”, edited by Glatter, O., and Kratky, O. (Academic Press, London, 1982).Google Scholar
Warren, B.E., Acta Cryst. 12, 837 (1959).CrossRefGoogle Scholar
Al-Thani, H.A. and Hasoon, F.S., MRS Advances, 53, 3215 (2017)CrossRefGoogle Scholar
Shibayama, M., Nomura, S., Hashimoto, T., and Thomas, E.L., J. Appl. Phys. 66, 4188 (1989).CrossRefGoogle Scholar
Fagin, L.A. and Svergun, D.I., “Structure Analysis by Small-Angle X-ray and Neutron Scattering”, (Plenum, New York, 1987).Google Scholar