Effects of SrTiO_(3)/TiO_(2) buffer layer on structural and electrical properties of BiFeO_(3) thin films grown on GaN (0002)

摘要

BiFeO_(3)(BFO) films were deposited by pulsed laser deposition on GaN(0002)/c-sapphire. X-ray diffraction data show that BFO(111) epitaxial films was deposited on SrTiO_(3)/TiO_(2) double-layer buffered GaN, compared to the polycrystalline film grown directly on GaN. The epitaxial relationships of BFO film with SrTiO_(3)/TiO_(2) buffer layers were BFO 11-2(111)//GaN 1-100(0002) as revealed by XRD phi scans. Furthermore, BFO films on SrTiO_(3)/TiO_(2) buffer exhibited enhanced electric properties compared to these deposited directly on GaN. The remnant polarization was improved about 30percent while the leakage current was reduced by nearly three orders of magnitude. The epitaxial growth promoted by the SrTiO_(3)/TiO_(2) buffer layer is a pivotal parameter in the improved electric properties of BFO films on GaN (0002).