原位电学引入PbTiO3铁电薄膜高密度90°畴的研究

原位电学引入PbTiO3铁电薄膜高密度90°畴的研究

李 柱，刘中然，陈嘉璐，任召辉，田 鹤*

（1. 浙江大学 电子显微镜中心，硅材料国家重点实验室，材料科学与工程学院，浙江 杭州 310027；2. 浙江大学 硅材料国家重点实验室，材料科学与工程学院，浙江 杭州310027）

摘 要 铁电薄膜材料在低功耗、高密度信息存储领域具有广阔的应用前景，有望制造高性能微电子器件。尤其是铁电体中的90°畴，在提高压电响应、应变协调以及柔性器件的性能中发挥着关键作用。大多数90°畴的形成是通过晶格失配、改变沉积温度和速率等生长条件获得的，90°畴的生成难以精确可控，制约了90°畴在铁电薄膜中的应用。因此，本文采用原位电学方法，在PbTiO3铁电薄膜中生成了高密度90°畴和类涡旋畴，通过对外加电场下90°畴的动态形成和原子级结构的研究，为铁电薄膜中90°畴的调控与应用了提供新的方法和理论依据。

关键词 原位透射电子显微镜；铁电薄膜；PbTiO3；90°畴

中图分类号：TN384；TG115.21+5.3；TB34；TB82 文献标识码：A doi:10.3969/j.issn.1000-6281.2025.02.001

In situ electrical introduction of PbTiO3 ferroelectric thin films with high density 90° domains

LI ZHU，LIU ZHONGran，CHEN Jialu，REN Zhaohui，TIAN He* (1. Zhejiang University Electron Microscope Center, State Key Laboratory of Silicon Materials, School of Materials Science and Engineering, Hangzhou Zhejiang 310027；2. Zhejiang University, State Key Laboratory of Silicon Materials, School of Materials Science and Engineering, Hangzhou Zhejiang 310027, China)

Abstract Ferroelectric thin-film materials have promising applications in low-power and high-density information storage and are poised to enable the fabrication of high-performance microelectronic devices. 90° domains in ferroelectrics are crucial for enhancing piezoelectric responses, strain coordination, and the performance of ferroelectric logic devices. Most of the 90° domains generate due to lattice mismatch or by adjusting growth parameters, such as deposition temperature and rate. However, the precise control over their generation remains challenging. This limitation hinders the broader application of 90° domains in ferroelectric thin films. In this study, we used in situ electrical methods to generate high-density 90° domains and vortex-like domains in PbTiO3 ferroelectric thin films. We investigated the dynamic formation and atomic-level structure of these 90° domains under an applied electric field. This study provides a new method and theoretical foundation for controlling and utilizing 90° domains in ferroelectric thin films.

Keywords In situ transmission electron microscopy; ferroelectric thin film; PbTiO3; 90° domain

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