Design of surface symmetry for low-voltage ferroelectric switching

Abstract

Multiferroic materials present transformative opportunities for next-generation non-volatile nanoelectronics in beyond-CMOS devices. The pervasive demands for miniaturized and energy-efficient nanoelectronic devices necessitate the reductions in operating voltages for ferroelectric-based devices. However, this objective remains fundamentally hindered by the intrinsic high coercive fields of conventional ferroelectric materials. Here, we demonstrate an innovative surface symmetry engineering method that simultaneously reduces the operating voltage and enhances polarization retention stability of the multiferroic BiFeO3 thin film. Notably, through aqueous-solution-mediated hydroxyl surface modification, we demonstrate a >30% decrease in coercive voltage while attaining a record-low coercive voltage of ∼0.45 V on 3 nm film thickness. This surface symmetry engineering establishes a promising approach for achieving low-power consumption, high-density, and non-volatile storage capabilities of ferroelectric materials.