BiFeO3 THIN FILMS: INFLUENCE OF DOPING ON STRUCTURE AND PROPRETIES

Abstract

Thin films of BiFeO3 and doped BiFeO3 were prepared by chemical solution deposition method. Because of low electrical resistivity of BiFeO3 which often prevents it to exhibit ferroelectric properties, several elements were used as dopants, partially replacing Bi3+ (Y3+, Sr2+) or Fe3+ (Ti4+, Zr4+) ions. Dopants may also reduce the size of the grains improving the magnetic properties. Pure BiFeO3 phase was formed for all compositions without preferred orientation. All films are around 300 nm thick, with relatively densely packed round grains of the size well below 100 nm as it is presented with micrographies in Fig. 1. Some of the dopants have lowered the size of the grains and increased electrical resistivity enough for ferroelectric hysteresis to be measured at fields above 100 kV/cm