Enhanced ferroelectric and piezoelectric properties in doped lead-free (Bi_(0.5)Na_(0.5))_(0.94)Ba_(0.06)TiO_3 thin films

摘要

Doping effects with respect to the electrical properties of morphotropic phase boundary (Bi_(0.5)Na_(0.5))_(0.94)Ba_(0.06)TiO_3 thin films epitaxially grown on CaRuO_3 electroded (LaAlO_3)_(0.3)(Sr_2AlTaO_6)_(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 μC/cm~2 and a remanent piezoelectric coefficient d_(33f) 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.