Chouprik Anastasia, Negrov Dmitrii, Tsymbal Evgeny Y, Zenkevich Andrei
Moscow Institute of Physics and Technology, Dolgoprudny, Moscow region, Russia.
Nanoscale. 2021 Jul 15;13(27):11635-11678. doi: 10.1039/d1nr01260f.
The discovery of ferroelectricity in polycrystalline thin films of doped HfO2 has reignited the expectations of developing competitive ferroelectric non-volatile memory devices. To date, it is widely accepted that the performance of HfO2-based ferroelectric devices during their life cycle is critically dependent on the presence of point defects as well as structural phase polymorphism, which mainly originates from defects either. The purpose of this review article is to overview the impact of defects in ferroelectric HfO2 on its functional properties and the resulting performance of memory devices. Starting from the brief summary of defects in classical perovskite ferroelectrics, we then introduce the known types of point defects in dielectric HfO2 thin films. Further, we discuss main analytical techniques used to characterize the concentration and distribution of defects in doped ferroelectric HfO2 thin films as well as at their interfaces with electrodes. The main part of the review is devoted to the recent experimental studies reporting the impact of defects in ferroelectric HfO2 structures on the performance of different memory devices. We end up with the summary and perspectives of HfO2-based ferroelectric competitive non-volatile memory devices.
在掺杂的HfO₂多晶薄膜中发现铁电性，重新点燃了人们对开发具有竞争力的铁电非易失性存储器件的期望。迄今为止，人们普遍认为，基于HfO₂的铁电器件在其生命周期内的性能严重依赖于点缺陷的存在以及结构相多态性，而这两者主要也都源于缺陷。这篇综述文章的目的是概述铁电HfO₂中的缺陷对其功能特性以及由此产生的存储器件性能的影响。我们首先简要总结经典钙钛矿铁电体中的缺陷，然后介绍介电HfO₂薄膜中已知的点缺陷类型。此外，我们还讨论了用于表征掺杂铁电HfO₂薄膜及其与电极界面处缺陷浓度和分布的主要分析技术。综述的主要部分致力于近期的实验研究，这些研究报告了铁电HfO₂结构中的缺陷对不同存储器件性能的影响。我们最后总结了基于HfO₂的铁电竞争性非易失性存储器件的现状并展望了其前景。
