Coexistence and interplay of two ferroelectric mechanisms in Zn1-xMgxO

TL;DR

This study uncovers the coexistence of two ferroelectric mechanisms in Zn1-xMgxO and introduces a novel 'fringing-ridge' polarization switching process, advancing understanding of ferroelectric behavior for technological applications.

Contribution

It reveals the simultaneous presence of two ferroelectric subsystems in Zn1-xMgxO and proposes a new polarization switching mechanism, challenging traditional domain growth models.

Findings

Identification of two ferroelectric subsystems in Zn1-xMgxO

Introduction of the 'fringing-ridge' polarization switching mechanism

Contradiction of conventional domain growth in ferroelectrics

Abstract

Ferroelectric materials promise exceptional attributes including low power dissipation, fast operational speeds, enhanced endurance, and superior retention to revolutionize information technology. However, the practical application of ferroelectric-semiconductor memory devices has been significantly challenged by the incompatibility of traditional perovskite oxide ferroelectrics with metal-oxide-semiconductor technology. Recent discoveries of ferroelectricity in binary oxides such as Zn1-xMgxO and Hf1-xZrxO have been a focal point of research in ferroelectric information technology. This work investigates the ferroelectric properties of Zn1-xMgxO utilizing automated band excitation piezoresponse force microscopy. Our findings reveal the coexistence of two ferroelectric subsystems within Zn1-xMgxO. We propose a "fringing-ridge mechanism" of polarization switching that is characterized by initial lateral expansion of nucleation without significant propagation in depth, contradicting the conventional domain growth process observed in ferroelectrics. This unique polarization dynamics in Zn1-xMgxO suggests a new understanding of ferroelectric behavior, contributing to both the fundamental science of ferroelectrics and their application in information technology.