LAUSR

Abstract We report that Dy doping can be used to enhance ferroelectric properties and reduce leakage current in (001) epitaxial Bi1-xDyxFeO3 (BDxFO) thin films where x = 0.05, 0.075, 0.1, 0.125. The 120 nm thin BDxFO films were prepared by pulsed laser deposition (PLD). Saturated ferroelectric hysteresis (P-E) loops were observed at room temperature with an increase in remanent polarization (Pr) with the increase in applied electric field and Dy concentration. The improved Pr in BDxFO films from x = 0.05 to 0.1 is attributed to reduction in oxygen vacancies with an increase in Dy content that prevents electric domain back-switching. However, BDxFO (x = 0.125) film exhibit leaky and unsaturated loop which may be due to the appearance of microscopic defects in the film. The leakage current in BDxFO films decreased by an order of magnitude as Dy content increased from x = 0.05 to 0.1. The detailed leakage current mechanism analysis is also presented. The results of positive up negative down (PUND) method confirmed that intrinsic polarization is due to ferroelectricity and not due to leakage. Relative permittivity (ɛ') of BDxFO films increased whereas dielectric loss tangent (tan δ) reduced as Dy content increased from x = 0.05 to 0.1.