Annealing-induced changes in the nanoscale electrical homogeneity of bismuth ferrite dielectric thin films

In this study, we investigated the effects of forming gas (7% H2 + 93% Ar) annealing (FGA) and recovery annealing (RA) in ambient oxygen on the structure and electrical properties of BiFeO3 (BFO) thin films. X-ray diffraction results indicate that BFO remains in the perovskite phase following FGA. However, the spatial distribution of current maps obtained by conductive atomic force microscopy shows that FGA-treated BFO thin films are less electrically insulating than those without prepared thermal annealing. Recovery annealing improves the structural and chemical homogeneity of the FGA-treated films, thereby increasing the electrical resistance of the films.