Conducting atomic force microscopy studies on domain wall currents of Bi5 Ti3 FeO15 nanodots fabricated by anodic aluminum oxide nanotemplate and sol-gel process

Abstract

We investigated the local current characteristics of Bi₅ Ti₃ FeO₁₅ (BTFO) nanodots on Nb-doped SrTiO₃ substrates affected by their ferroelectric domain structures and domain walls. The BTFO nanodots with a diameter of about 50 nm were fabricated by anodic aluminum oxide nanotemplates and a BTFO sol-gel process. Based on a piezoresponse force microscope, it was confirmed that domain walls were formed in the ferroelectric domain structures of the epitaxial BTFO nanodots. Current changes due to ferroelectric tunneling junctions according to ferroelectric polarizations in epitaxial BTFO nanodots were confirmed by conduction atomic force microscopy. In particular, the domain walls formed in the epitaxial BTFO nanodots formed high currents compared to the currents in ferroelectric tunneling junctions due to polarizations. RESEARCH HIGHLIGHTS: Ferroelectric Bi₅ Ti₃ FeO₁₅ nanodots with a diameter of 50 nm. Ferroelectric domain structures observed with piezoresponse force microscopy. High domain wall currents observed at domain boundaries observed with conducting atomic force microscopy.

Keywords: conducting atomic force microscopy; domain wall conduction; domain wall currents; ferroelectric Bi5T3FeO15 nanodots; peizoresponse force microscope.