Probing Nanoscale Functional Properties of Perovskite and Wurtzite Ferroelectrics via Scanning Probe Microscopy

Scanning probe microscopy (SPM) is considered essential for visualizing, analyzing, controlling, and engineering novel functional attributes of nanoscale materials. Diverse SPM-based methodologies were employed to investigate the topography, ferroelectricity and conductivity of perovskite and wurtzite ferroelectric materials for prospective applications in science and technology. Ferroelectrics exhibit a switchable spontaneous polarization when subjected to an electric field and are instrumental in developing low-energy nanoelectronics. Topologically tailored nanoscale ferroelectrics have attracted substantial attention in the pursuit of pioneering electronic functionalities. Here, we find a novel approach for tailoring topological textures in engineered ferroelectric nanowires of BiFeO3 with the formation of wave-like polarization. Utilizing high-resolution SPM techniques, controlled reorientation of the periodic charged domain wall texture is demonstrated upon nanowire formation. The domain structure can be transformed into wave-like patterns that are sought after for new electronics technology. Our discovery holds significance for the prospective design of forthcoming negative capacitance components. Further, a robust switchable polarization in individual nanocrystallites within thin films of Mg-doped zinc oxide (MZO) with a polar wurtzite crystal structure is demonstrated. Through various SPM techniques, voltage control of the polarization and coupled electronic transport behavior is unveiled with an adjustable effective longitudinal piezoelectric coefficient by controlling the doping concentration. These findings provide valuable insight into achieving ferroelectricity in simpler metal oxides compatible with CMOS technology. In addition, we showcase a method utilizing switchable polarization in polar wurtzite structure MZO to customize the Schottky barrier at the ferroelectric/metal interface. Asymmetric resistive switching behavior has been found in Pt/Mg0.2Zn0.8O/ITO heterostructures with modulated back-to-back Schottky diode configuration. This finding introduces an innovative method for engineering polarity-controlled Schottky barriers, revealing their significant impact on device performance. In summary, these studies highlight the capability of SPM to provide detailed nanoscale insights into the functional properties of materials with perovskite and wurtzite structures, thus contributing to the development of prototype nanoelectronics components.

Grantor dc:publisher

UNSW, Sydney

Year dc:date

2024

Author dc:creator

• Zhang, Haoze

• Ferroelectric
• Scanning Probe Microscopy
• Nanoelectronics
• Perovskite
• Wurtzite
• anzsrc-for: 400909 Photonic and electro-optical devices, sensors and systems (excl. communications)

Statement dc:rights

• open access
• CC BY 4.0
• free_to_read

Licence

• https://purl.org/coar/access_right/c_abf2
• https://creativecommons.org/licenses/by/4.0/

Language dc:language

en

Identifier

https://doi.org/10.26190/unsworks/25569

OAI identifier oai:identifier

oai:unsworks.library.unsw.edu.au:1959.4/101866