Effect of the Intrinsic Width on the Piezoelectric Force Microscopy of a Single Ferroelectric Domain Wall

TL;DR

This paper derives analytical formulas for PFM profiles of ferroelectric domain walls, accounting for intrinsic width and dielectric anisotropy, aiding quantitative analysis of ferroelectric memory device performance.

Contribution

It introduces closed-form analytical expressions for PFM profiles considering finite domain wall width and dielectric anisotropy, advancing the understanding of PFM image formation.

Findings

Analytical PFM profiles incorporate intrinsic domain wall width.

Profiles are convolutions of intrinsic profile and PFM resolution.

Provides tools for quantitative analysis of ferroelectric domain walls.

Abstract

Intrinsic domain wall width is a fundamental parameter that reflects bulk ferroelectric properties and governs the performance of ferroelectric memory devices. We present closed-form analytical expressions for vertical and lateral piezoelectric force microscopy (PFM) profiles for the conical and disc models of the tip, beyond point charge and sphere approximations. The analysis takes into account the finite intrinsic width of the domain wall, and dielectric anisotropy of the material. These analytical expressions provide insight into the mechanisms of PFM image formation and can be used for quantitative analysis of the PFM domain wall profiles. PFM profile of a realistic domain wall is shown to be the convolution of its intrinsic profile and resolution function of PFM.