Effects of SRO Buffer Layer on Multiferroic BiFeO3 Thin Films

Abstract

Crystallization, surface morphology, and electrical behavior of BiFeO3 thin films are improved by SrRuO3 (SRO) buffer layer with optimized grain size. Large‐grained SRO buffer layer promotes the growth of dense multiferroic BiFeO3 (BFO) thin films and reduces structural defects. Phase identification by using X‐ray diffraction and surface morphology studies by using scanning electron microscopy show that the large‐grained SRO buffer layer formed by sputtering thicker SRO films promotes the formation of the perovskite phase as well as the crystallinity. These BFO films have also shown reduced leakage current, as suggested by the weaker frequency dependence of the ferroelectric hysteresis loops as compared with the BFO films deposited on smaller‐grained SRO buffer layer. Investigation into the dielectric properties and fatigue endurance reveals that the structural defects of the BFO thin film have also been reduced by employing the larger‐grained SRO buffer layer.