Contribution of Drude and Brendel Model Terms to the Dielectric Function; A case of TiO2:Nb Thin Films

Christopher Mkirema Maghanga; Maurice M Mwamburi

doi:10.21467/jmsm.1.1.3-7

Authors

Christopher Mkirema Maghanga Department of Biological & Physical Sciences, Kabarak University, Kenya
Maurice M Mwamburi Department of Physics, University of Eldoret, Kenya

DOI:

https://doi.org/10.21467/jmsm.1.1.3-7

Abstract

Parametric modeling provides a mean of deeper understanding to the properties of materials. Dielectric function is one of the key parameters which can provide information on the dielectric nature of a thin film or bulk materials. It can be obtained by modeling the material using appropriate existing, new or modified models. In our work, we utilized existing Brendel and Drude models to extract the optical constants from spectrophotometric data of fabricated undoped and niobium doped titanium oxide thin films. The individual contributions by the two models were studied to establish influence on the dielectric function. The effect of dopants on their influences was also analyzed. Results indicate a minimal contribution from the Drude term due to the dielectric nature of the undoped films. However as doping levels increase, the rise in the concentration of free electrons favors the use of Drude model.

Keywords:

Brendel Model, Drude model, titanium Oxide, Modelling, titanium oxide

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References

D. S. Ginley, Ed., Handbook of Transparent Conductors. Boston, MA: Springer US, 2011.

D. E. Aspnes, “Optical properties of thin films,” Thin Solid Films, vol. 89, no. 3, pp. 249–262, Mar. 1982.

J. Singh and Wiley InterScience (Online service), Optical properties of condensed matter and applications. John Wiley & Sons, 2006.

M. I. Marković and A. D. Rakić, “Determination of optical properties of aluminium including electron reradiation in the Lorentz-Drude model,” Opt. Laser Technol., vol. 22, no. 6, pp. 394–398, Dec. 1990.

M. Vos and P. L. Grande, “Simple model dielectric functions for insulators,” J. Phys. Chem. Solids, vol. 104, pp. 192–197, May 2017.

F. (Frederick) Wooten, Optical properties of solids. Academic Press, 1972.

R. Brendel and D. Bormann, “An infrared dielectric function model for amorphous solids,” J. Appl. Phys., vol. 71, no. 1, pp. 1–6, Jan. 1992.

C. C. Kim, J. W. Garland, H. Abad, and P. M. Raccah, “Modeling the optical dielectric function of semiconductors: Extension of the critical-point parabolic-band approximation,” Phys. Rev. B, vol. 45, no. 20, pp. 11749–11767, May 1992.

A. D. Rakić, A. B. Djurišić, J. M. Elazar, and M. L. Majewski, “Optical properties of metallic films for vertical-cavity optoelectronic devices,” Appl. Opt., vol. 37, no. 22, p. 5271, Aug. 1998.

C. M. Maghanga, J. Jensen, G. A. Niklasson, C. G. Granqvist, and M. Mwamburi, “Transparent and conducting TiO2:Nb films made by sputter deposition: Application to spectrally selective solar reflectors,” Sol. Energy Mater. Sol. Cells, vol. 94, no. 1, pp. 75–79, Jan. 2010.

C. M. Maghanga, G. A. Niklasson, and C. G. Granqvist, “Optical properties of sputter deposited transparent and conducting TiO2:Nb films,” Thin Solid Films, vol. 518, no. 4, pp. 1254–1258, Dec. 2009.

V. Ondok and J. Musil, “Effect of Hydrogen on Reactive Sputtering of Transparent Oxide Films,” Plasma Process. Polym., vol. 4, no. S1, pp. S319–S324, Apr. 2007.

J. Musil, P. Baroch, J. Vlček, K. H. Nam, and J. G. Han, “Reactive magnetron sputtering of thin films: present status and trends,” Thin Solid Films, vol. 475, no. 1–2, pp. 208–218, Mar. 2005.

W. Theiss, “W.Theiss Hard-and Software for Optical Spectroscopy Technical manual SCOUT Optical Spectrum Simulation,” 2015.

O. Peña-Rodríguez, “Modelling the dielectric function of Au-Ag alloys,” J. Alloys Compd., vol. 694, pp. 857–863, Feb. 2017.