High-density domain nanodot arrays and domain wall current characterization in lithium niobate thin films

Abstract

Ferroelectric nanostructures demonstrate significant potential for novel electronic devices due to their unique conductive properties. This study employs piezoelectric force microscopy tip poling to fabricate nanodomain arrays in Z-cut lithium niobate thin films, achieving minimum domain diameters of 80 nm with stability exceeding 100 days. A spherical charged tip model validates the evolution law governing domain size and polarization pulse duration. Within the 298–398 K temperature range, domain walls consistently exhibit linear current–voltage characteristics: Under 10 V bias at 125 °C, single-point domain wall currents reach 10 nA and current density attained 1.28 A/cm2. High-density arrays demonstrate a current density of 4 A/cm2. These findings provide pathways for developing high-precision temperature sensors and nonvolatile memories.