Hostname: page-component-586b7cd67f-dsjbd Total loading time: 0 Render date: 2024-11-23T09:18:03.929Z Has data issue: false hasContentIssue false

Kinetics of Frenkel Defect Formation in TiO2 from First Principles

Published online by Cambridge University Press:  21 August 2013

Sergey V. Barabash
Affiliation:
Intermolecular Inc, San Jose, CA, U.S.A.http://www.intermolecular.com. Electrical Engineering, Stanford University, Stanford, CA, U.S.A.
Charlene Chen
Affiliation:
Intermolecular Inc, San Jose, CA, U.S.A.http://www.intermolecular.com.
Dipu Pramanik
Affiliation:
Intermolecular Inc, San Jose, CA, U.S.A.http://www.intermolecular.com.
Blanka Magyari-Köpe
Affiliation:
Electrical Engineering, Stanford University, Stanford, CA, U.S.A.
Yoshio Nishi
Affiliation:
Electrical Engineering, Stanford University, Stanford, CA, U.S.A.
Get access

Abstract

Motivated by the unusual behavior of TiO2 films seen in electrical stress and defect annealing experiments, we studied the energy profile for forming a Frenkel defect in rutile TiO2, using first-principles calculations with a nudged-elastic-band method. We found strongly asymmetric diffusion barriers. The Frenkel pairs with small separation are exceedingly short-lived: the Ti interstitial position nearest to the the Ti vacancy is separated by only a 0.15eV barrier, and the next-nearest interstitial position is dynamically unstable. The formation enthalpies of Frenkel pairs with larger separation gradually vary between 4.2 and 5.0 eV, separated by 0.3-0.4eV barriers along the (001) direction. Contrary to some previous studies, we do not find Frenkel configurations with tetrahedrally bonded Ti interstitials. The very low barriers for Frenkel defect evolution are consistent with the observations from the electrical stress damage annealing experiments.

Type
Articles
Copyright
Copyright © Materials Research Society 2013 

Access options

Get access to the full version of this content by using one of the access options below. (Log in options will check for institutional or personal access. Content may require purchase if you do not have access.)

References

REFERENCES

Li, X. et al. ., Acta Materialia 57, 5882 (2009).CrossRefGoogle Scholar
Baumard, J. F. et al. ., J. Chem. Phys. 67, 857 (1977).CrossRefGoogle Scholar
Smyth, D.M.. The defect chemistry of metal oxides (2000).Google Scholar
He, J. et al. ., Acta Materialia, 55, 4325 (2007).CrossRefGoogle Scholar
He, J. and Sinnott, , J.Am.Ceram.Soc. 88 (2005).Google Scholar
Iddir, H. et al. ., Phys.Rev. B. 75 (2007).CrossRefGoogle Scholar
Asaduzzaman, et al. . J.Phys.Chem.C, 114, 19649 (2010).CrossRefGoogle Scholar
Wang, Z. W. et al. ., Surface Science 606, 186 (2012).CrossRefGoogle Scholar
Kresse, G. and Hafner, J., Phys. Rev. B 48, 13115 (1993); G. Kresse and J. Furthmüller, Comput. Mater. Sci. 6, 15(1996); Phys. Rev. B 54, 11169 (1996).CrossRefGoogle Scholar
Blöchl, P. E., Phys. Rev. B 50, 17953 (1994); G. Kresse and D.Joubert, ibid. 59, 1758(1999).CrossRefGoogle Scholar
Foster, A.S., Phys.Rev. Lett. 89, 225901 (2002).CrossRefGoogle Scholar
Brossmann, U., J. Appl. Phys. 85, 7646 (1999); Y. Yamamoto et al., Nucl. Instrum. Methods B, 303,42(2013).CrossRefGoogle Scholar