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Modeling evaporation, ion-beam assist, and magnetron sputtering of TiO2 thin films over realistic timescales

Published online by Cambridge University Press:  01 December 2011

Sabrina Blackwell*
Affiliation:
Department of Mathematical Sciences, Loughborough University, Loughborough, Leicestershire, LE11 3TU, United Kingdom
Roger Smith
Affiliation:
Department of Mathematical Sciences, Loughborough University, Loughborough, Leicestershire, LE11 3TU, United Kingdom
Steven D. Kenny
Affiliation:
Department of Mathematical Sciences, Loughborough University, Loughborough, Leicestershire, LE11 3TU, United Kingdom
Louis J. Vernon
Affiliation:
Department of Mathematical Sciences, Loughborough University, Loughborough, Leicestershire, LE11 3TU, United Kingdom
John M. Walls
Affiliation:
Department of Electronic and Electrical Engineering, Loughborough University, Loughborough, Leicestershire, LE11 3TU, United Kingdom
*
a)Address all correspondence to this author. e-mail: [email protected]
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Abstract

Results are presented for modeling the growth of TiO2 on the rutile (110) surface. We illustrate how long time scale dynamics techniques can be used to model thin film growth at realistic growth rates. The system evolution between deposition events is achieved through an on-the-fly Kinetic Monte Carlo method, which finds diffusion pathways and barriers without prior knowledge of transitions. We examine effects of various experimental parameters, such as substrate bias, plasma density, and stoichiometry of the deposited species. Growth of TiO2 via three deposition methods has been investigated: evaporation (thermal and electron beam), ion-beam assist, and reactive magnetron sputtering. We conclude that the evaporation process produces a void filled, incomplete structure even with the low-energy ion-beam assist, but that the sputtering process produces crystalline growth. The energy of the deposition method plays an important role in the film quality.

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Articles
Copyright
Copyright © Materials Research Society 2011

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References

REFERENCES

1.Zhang, Z., Anderson, W.A., and Moo-Young, M.: Rigorous modeling of UV absorption by TiO2 films in a photocatalytic reactor. AIChE J. 46, 1461 (2000).CrossRefGoogle Scholar
2.Wang, H., Su, C., Chen, H., Liu, Y., Hsu, Y., Hsu, N., and Li, W.: Preparation of nanoporous TiO2 electrodes for dye-sensitized solar cells. J. Nanomater. 2011, 7 (2011).CrossRefGoogle Scholar
3.Schwarz, O., Loyen, D., Jockusch, S., Turro, N.J., and Durr, H.: Preparation and application of new ruthenium(ii) polypyridyl complexes as sensitizers for nanocrystalline TiO2. J. Photochem. Photobiol. A Chem. 132, 91 (2000).CrossRefGoogle Scholar
4.Wolfe, D.E. and Singh, J.: Microstructural evolution of titanium nitride TiN coatings produced by reactive ion beam-assisted, electron beam physical vapor deposition RIBA, EBPVD. J. Mater. Sci. 34, 2997 (1999).CrossRefGoogle Scholar
5.Bange, K., Ottermann, C.R., Anderson, O., Jeschkowski, U., Laube, M., and Feile, R.: Investigations of TiO2 films deposited by different techniques. Thin Solid Films 197, 279 (1991).Google Scholar
6.Zhang, F., Jin, S., Mao, Y., Zheng, Z., Chen, Y., and Liu, X.: Surface characterization of titanium oxide films synthesized by ion beam enhanced deposition. Thin Solid Films 310, 29 (1997).Google Scholar
7.Kim, S.H., Lee, J.H., Hwangbo, C.K., and Lee, S.M.: DC reactive magnetron sputtering with Ar ion-beam assistance for titanium oxide films. Surf. Coat. Technol. 158-159, 457 (2002).Google Scholar
8.Zeman, P. and Takabayashi, S.: Nano-scaled photocatalytic TiO2 thin films prepared by magnetron sputtering. Thin Solid Films 433, 57 (2003).CrossRefGoogle Scholar
9.Sicha, J., Musil, J., Meissner, M., and Cerstvy, R.: Nanostructure of photocatalytic TiO2 films sputtered at temperatures below 200 C. Appl. Surf. Sci. 254, 3793 (2008).CrossRefGoogle Scholar
10.Eufinger, K., Janssen, E.N., Poelman, H., Poelman, D., De Gryse, R., and Marin, G.B.: The effect of argon pressure on the structural and photocatalytic characteristics of TiO2 thin films deposited by d.c. magnetron sputtering. Thin Solid Films 515, 425 (2006).Google Scholar
11.Kim, S.H. and Hwangbo, C.K.: Influence of Ar ion-beam assistance and annealing temperatures on properties of TiO2 thin films deposited by reactive DC magnetron sputtering. Thin Solid Films 475, 155 (2005).Google Scholar
12.Georgieva, V., Voter, A.F., and Bogaerts, A.: Understanding the surface-diffusion processes during magnetron sputter-deposition of complex oxide Mg-Al-O thin films. Cryst. Growth Des. 11, 2553 (2011).CrossRefGoogle Scholar
13.Hu, G., Orkoulas, G., and Christofides, P.D.: Model predictive control of film porosity in thin film deposition, in American Control Conference, 2009, pp. 47974804.Google Scholar
14.Gordiets, B.F., Andujar, J.L., Corbella, C., and Bertran, E.: Kinetic model of thin film growth by vapor deposition. Eur. Phys. J D 35(3), 505 (2005).Google Scholar
15.Vernon, L.J., Smith, R., and Kenny, S.D.: Modelling of deposition processes on the TiO2 rutile (110) surface. Nucl. Instrum. Methods Phys. Res., Sect. B 267, 3022 (2009).Google Scholar
16.Vernon, L.J., Kenny, S.D., and Smith, R.: Growth of TiO2 surfaces following low energy (≤40 eV) atom and small cluster bombardment. Nucl. Instrum. Methods Phys. Res., Sect. B 268, 2942 (2010).Google Scholar
17.Vernon, L.J., Kenny, S.D., Smith, R., and Sanville, E.J.: Growth mechanisms for TiO2 at its rutile (110) surface. Phys. Rev. B 83, 075412 (2011).Google Scholar
18.Smith, R. and Moller, W.: Surface erosion of TiO2 subjected to energetic oxygen bombardment, in Advanced Materials for Applications in Extreme Environments, edited by Samaras, M., Fu, C.C., Byun, T.S., Stan, M., Ogawa, T., Motta, A., Simeone, D., Smith, R., Wang, L., Zhang, X., Kraft, O., Demkowicz, M., and Li, M. (Mater. Res. Soc. Symp. Proc. 1298, Warrendale, PA, 2011) p. 191.Google Scholar
19.Sanville, E.J., Vernon, L.J., Kenny, S.D., Smith, R., Moghaddam, Y., Browne, C., and Mulheran, P.: Surface and interstitial transition barriers in rutile (110) surface growth. Phys. Rev. B 80, 235308 (2009).Google Scholar
20.Wendt, S., Sprunger, P.T., Lira, E., Madsen, G.K.H., Li, Z., Hansen, J., Matthiesen, J., Blekinge-Rasmussen, A., Lægsgaard, E., Hammer, B., and Besenbacher, F.: The role of interstitial sites in the Ti3d defect state in the band gap of titania. Science 320, 1755 (2008).CrossRefGoogle Scholar
21.Voter, A.F., Montalenti, F., and Germann, T.C.: Extending the time scale in atomistic simulation of materials. Annu. Rev. Mater. Res. 32, 321 (2002).CrossRefGoogle Scholar
22.Henkelman, G. and Jonsson, H.: Long time scale kinetic Monte Carlo simulations without lattice approximation and predefined event table. J. Chem. Phys. 115, 9657 (2001).CrossRefGoogle Scholar
23.Voter, A.F.: Radiation effects in solids, in Introduction to the Kinetic Monte Carlo Method (Springer, NATO Publishing Unit, Dordrecht, Netherlands, 2005).Google Scholar
24.Rappe, A.K. and Goddard, W.A.: Charge equilibration for molecular dynamics simulations. J. Phys. Chem. 95, 3358 (1991).CrossRefGoogle Scholar
25.Hallil, A., Tetot, R., Berthier, F., Braems, I., and Creuze, J.: Use of a variable-charge interatomic potential for atomistic simulations of bulk, oxygen vacancies, and surfaces of rutile TiO2. Phys. Rev. B 73, 165406 (2006).CrossRefGoogle Scholar
26.Vernon, L.J.: Modelling the Growth of TiO2. PhD thesis, Loughborough University, (2010).Google Scholar
27.Berendsen, H.J.C., Postma, J.P.M., van Gunsteren, W.F., DiNola, A., and Haak, J.R.: Molecular dynamics with coupling to an external bath. J. Chem. Phys. 81(8), 3684 (1984).CrossRefGoogle Scholar
28.Henkelman, G., Uberuaga, B.P., and Jonsson, H.: A climbing image nudged elastic band method for finding saddle points and minimum energy paths. J. Chem. Phys. 113(22), 9901 (2000).Google Scholar
29.Henkelman, G. and Jonsson, H.: Improved tangent estimate in the nudged elastic band method for finding minimum energy paths and saddle points. J. Chem. Phys. 113(22), 9978 (2000).Google Scholar
30.Henkelman, G., Sheppard, D., and Terrell, R.: Optimization methods for finding minimum energy paths. J. Chem. Phys. 128(134106),1 (2008).Google Scholar
31.Vineyard, G.H.: Frequency factors and isotope effects in solid state rate processes. J. Phys. Chem. Solids 3, 121 (1957).CrossRefGoogle Scholar
32.Walls, J.M., Hall, D.D., Teer, D.G., and Delcea, B.L.: A comparison of vacuum-evaporated and ion-plated thin films using Auger electron spectroscopy. Thin Solid Films 54, 303 (1978).CrossRefGoogle Scholar