The screening effects influence on the nano-domain tailoring in ferroelectrics-semiconductors

TL;DR

This study models nano-domain formation in ferroelectric-semiconductors, revealing how screening effects and electric fields influence domain sizes and threshold formation, aligning with recent experimental findings.

Contribution

It introduces modified models accounting for Debye screening and surface recharging, providing more accurate predictions of nano-domain sizes in ferroelectric-semiconductors.

Findings

Depolarization field energy and screening effects significantly reduce domain sizes.

Domains form with finite size at a critical voltage, indicating a threshold behavior.

Results align with recent theoretical and experimental studies.

Abstract

We calculate the realistic sizes of nano-domains recorded by the electric field of atomic force microscope tip in BaTiO3 and LiNbO3 ferroelectric-semiconductors in contrast to the over-estimated ones obtained in the previous works. We modified the existing models of domain formation allowing for the Debye screening, recharging of sluggish surface screening layers caused by emission current between the tip apex and the domain butt surface and the redistribution of domain depolarization field induced by the charged tip apex. We have shown that the depolarization field energy of the domain butt, Debye screening effects and field emission at high voltages lead to the essential decrease of the equilibrium domain sizes. We obtained, that the domain length and radius do not decrease continuously with voltage decrease: the domain appears with non-zero length and radius at definite critical voltage. Such "threshold" domain formation is similar to the first order phase transition and correlates with recent theoretical and experimental investigations.