Enhanced ferroelectric and piezoelectric properties in doped lead-free (Bi0.5Na0.5)0.94Ba0.06TiO3 thin films

Doping effects with respect to the electrical properties of morphotropic phase boundary (Bi0.5Na0.5)(0.94)Ba0.06TiO3 thin films epitaxially grown on CaRuO3 electroded (LaAlO3)(0.3)(Sr2AlTaO6)(0.35) (001) substrates were investigated. Substantial enhancement of ferroelectricity and piezoelectricity has been achieved in La+Ce codoped films with a remanent polarization P-r of 29.5 mu C/cm(2) and a remanent piezoelectric coefficient d(33,f) of 31 pm/V, whereas Mn doping seems more favorite to reduce the leakage current by two order of magnitude. Both doped films exhibited diodelike I-V characteristics, which are correlated with resistance switching effect. (C) 2010 American Institute of Physics. [doi:10.1063/1.3518484]