Reversible plasma switching in epitaxial BiFeO3 thin films

Reversible plasma switching in epitaxial multiferroic BiFeO3 thin films was directly observed and analyzed using piezoresponse force microscopy. The polarization could be reversibly switched using oxygen plasma and a subsequent thermal annealing treatment in vacuum, respectively. The domain wall velocity during plasma switching, estimated to about 10(-8) m/s, is much slower compared to the normal electrical switching, however a large area of square centimeter scale could be stably switched. The results demonstrate that reversible plasma switching can be achieved by oxygen plasma treatment and it can be a useful tool for an electrode-less control of ferroelectric switching on large area. (C) 2010 American Institute of Physics. [doi: 10.1063/1.3431585]