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Indexed by:Journal Papers

Date of Publication:2015-10-01

Journal:PHYSICA STATUS SOLIDI-RAPID RESEARCH LETTERS

Included Journals:SCIE、EI、Scopus

Volume:9

Issue:10

Page Number:589-593

ISSN No.:1862-6254

Key Words:Si-doped HfO2; thin films; Rayleigh law; ferroelectric materials

Abstract:A wealth of studies have confirmed that the low-field hysteresis behaviour of ferroelectric bulk ceramics and thin films can be described using Rayleigh relations, and irreversible domain wall motion across the array of pining defects has been commonly accepted as the underlying micro-mechanism. Recently, HfO2 thin films incorporated with various dopants were reported to show pronounced ferroelectricity, however, their microscopic domain structure remains unclear till now. In this work, the effects of the applied electric field amplitude, frequency and temperature on the sub-coercive polarization reversal properties were investigated for 10 nm thick Si-doped HfO2 thin films. The applicability of the Rayleigh law to ultra-thin ferroelectric films was first confirmed, indicating the existence of a multi-domain structure. Since the grain size is about 20-30 nm, a direct observation of domain walls within the grains is rather challenging and this indirect method is a feasible approach to resolve the domain structure. (C) 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim