4.7 Article

Interface control of tetragonal ferroelectric phase in ultrathin Si-doped HfO2 epitaxial films

期刊

ACTA MATERIALIA
卷 207, 期 -, 页码 -

出版社

PERGAMON-ELSEVIER SCIENCE LTD
DOI: 10.1016/j.actamat.2021.116696

关键词

Epitaxial ferroelectric films; Sychrotron X-ray diffraction; Synchrotron X-ray absorption; High-resolution TEM; Pulsed laser deposition

资金

  1. National Natural Science Foundation of China [11604214, 51972157, 11964017]
  2. Foundation of Department of Education of Guangdong Province [2018KTSCX223]
  3. Foundation of Department of Science and Technology of Guangdong Province [2020A1515010814]
  4. Research Grants Council of the Hong Kong Special Administrative Region, China [PolyU152665/16E]
  5. Scientific Research Foundation of Advanced Talents (Innovation Team), DGUT [KCYCXPT2016004, TDQN2019003]
  6. Advanced Light Source, a DOE Office of Science User Facility [DE-AC02-05CH11231]

向作者/读者索取更多资源

By using ITO as the bottom electrode, genuine ultrathin epitaxial films of Si-doped HfO2 can be grown with good ferroelectric properties under epitaxial compressive strain; polar domains can be written and read using piezoforce microscopy and reversibly switched; ferroelectric polarization can be controlled by manipulating the ITO surface polarity to influence the interfacial electrostatic potential.
Nanoscaled HfO2-based ferroelectric thin films are a favored candidate for the integration of nextgeneration memory and logic devices. The unique advantage is that the ferroelectric polarization becomes more robust than the traditional perovskite ferroelectrics when the size is reduced. Understanding and controlling the ferroelectricity requires high-quality epitaxial thin films to explore intrinsic ferroelectric mechanism and evaluate device applications. Here, we report a semicoherent growth of ITO as a bottom electrode that enables genuine ultrathin epitaxial films of Si-doped HfO2 on YSZ([)(001]/[110)(]/[111]) substrates. The deposited films, which are under epitaxial compressive strain, display large ferroelectric polarization values up to 42 mu C/cm(2) and do not need wake-up cycling. Structural characterization reveals the presence of crystalline domains with short axes of the tetragonal structure oriented perpendicular to the substrate. Using piezoforce microscopy, polar domains can be written and read and can be reversibly switched with a phase change of 180 degrees. Ferroelectric polarization can be controlled by ITO surface polarity which can easily exploit the interfacial valance mismatch to influence the electrostatic potential across the interface. These findings have implications for our understanding of ferroelectric switching and offer easy method to manipulate domain reversal state in HfO2-based ferroelectric materials. (C) 2021 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved.

作者

我是这篇论文的作者
点击您的名字以认领此论文并将其添加到您的个人资料中。

评论

主要评分

4.7
评分不足

次要评分

新颖性
-
重要性
-
科学严谨性
-
评价这篇论文

推荐

暂无数据
暂无数据