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High-Field Conduction in Barium Titanate

J. F. Scott·F. D. Morrison·P. Zubko·D. J. Jung·P. Baxter·M. M. Saad·J. M. Gregg·R. M. Bowman
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Abstract

We present current-voltage studies of very thin (ca. 77 nm) barium titanate single crystals up to 1.3 GV/m applied field. These show that the mechanism of leakage current at high fields is that of space charge limited conduction (SCLC) in a regime with a continuous distribution of traps, according to the original model of Rose [Phys. Rev. 97, 1537 (1955)]. This study represents a factor of x5 in field compared with the early studies of BaTiO3 conduction [A. Branwood et al., Proc. Phys. Soc. London 79, 1161 (1962)]. Comparison is also given with ceramic multilayer barium titanate capacitors, which show similar SCLC behaviour. The data are shown to be completely incompatible with variable range hopping [B. I. Shklovskii, Sov. Phys. Semicond. 6, 1964 (1973)], despite the recent report of such mechanism in SrTiO3 films [D. Fuchs, M. Adam, and R. Schneider, J. Phys. IV France 11, 71 (2001)].

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J. F. Scott, F. D. Morrison, P. Zubko, D. J. Jung, P. Baxter, M. M. Saad, J. M. Gregg, R. M. Bowman. 2004-09-22. High-Field Conduction in Barium Titanate. https://doi.org/10.1063/1.1886899

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