辐照诱导的氧缺陷对PbTiO_(3)铁电薄膜畴壁特性的影响  

Effect of Oxygen Vacancy in PbTiO_(3)Ferroelectric Thin Film Induced by Irradiation on Domain Wall Characteristics of PbTiO_(3)Ferroelectric Thin Film

作　　者：刘凯 管小鹏 罗焱航 宋宏甲 钟向丽 王金斌 成娟娟 邹代峰 LIU Kai;GUAN Xiaopeng;LUO Yanhang;SONG Hongjia;ZHONG Xiangli;WANG Jinbin;CHENG Juanjuan;ZOU Daifeng(School of Materials Science and Engineering,Xiangtan University,Xiangtan,Hunan Province 411105,China;School of Materials Science and Engineering,Hunan University of Science and Technology;School of Physics and Electronic Science,Hunan University of Science and Technology;Hunan Provincial Key Laboratory of Advanced Materials for New Energy Storage and Conversion,Xiangtan,Hunan Province 411201,China)

机构地区：[1]湘潭大学材料科学与工程学院,湖南湘潭411105 [2]湖南科技大学材料科学与工程学院 [3]湖南科技大学物理与电子科学学院 [4]新能源储存与转换先进材料湖南省重点实验室,湖南湘潭411201

出　　处：《现代应用物理》2022年第2期149-159,共11页Modern Applied Physics

基　　金：国家自然科学基金资助项目(51902275,11847106,11875229,51872251);湖南省自然科学基金资助项目(2020JJ4288);湖南省教育厅科研基金资助项目(20B225,20B560);强脉冲辐射模拟与效应国家重点实验室基金资助项目(SKLIPR1911);抗辐照应用技术创新中心创新基金资助项目(KFZC2020020701)。

摘　　要：从辐照诱导的晶格缺陷对铁电畴壁作用的角度,开展了辐照对PbTiO_(3)铁电畴壁的原子和电子结构及其动力学演化作用机理的研究。首先,利用基于蒙特卡罗方法的SRIM软件包研究了辐照条件对铁电薄膜内辐照诱导的晶格缺陷的影响,结果表明,质子、氪离子入射造成PbTiO_(3)铁电薄膜晶格的缺陷主要是氧缺陷,且离子能量越高和入射角越小,产生氧缺陷的浓度越高、位置越深入及分布越分散。其次,基于第一性原理研究了氧缺陷分布及浓度对PbTiO_(3)材料180°和90°畴壁原子结构、电子结构及迁移的影响,结果表明:氧缺陷离畴壁越远,含氧缺陷畴壁系统的稳定性越低;随着氧缺陷数目增加,畴壁附近极化减小、畴壁宽度增大;氧缺陷使畴壁的金属性增强;氧缺陷会钉扎畴壁,阻碍畴壁移动。The atomic and electronic structure of PbTiO_(3) ferroelectric domain wall and its dynamic evolution mechanism are studied.Firstly,the effect of the irradiation on the lattice defects in ferroelectric thin films is investigated by SRIM software package based on Monte Carlo method.The results show that the lattice defects of PbTiO_(3) ferroelectric thin films caused by proton and krypton ions are mainly oxygen vacancy,and the higher the ion energy and the smaller the incident angle,the higher the concentration,the deeper the cite and the more dispersed the distribution of oxygen vacancy.Based on the first principles,the effects of oxygen vacancy distribution and concentration on the atomic structure,electronic structure,and migration of 180 degree and 90 degree of domain walls of PbTiO_(3) are studied.The results show that the farther the oxygen vacancy is from the domain wall,the lower the stability of the domain wall system containing oxygen vacancy.With the increase of the number of oxygen vacancy,the polarization near the domain wall decreases,and the width of the domain wall increases.The oxygen vacancy enhances the metallicity of domain walls,and would pin the domain wall and hinder the migration of domain wall.

关 键 词：铁电存储器 铁电畴壁 辐照 氧缺陷 畴壁导电性 畴壁迁移 

分 类 号：O571[理学—粒子物理与原子核物理] TL99[理学—物理]