退火温度对BCZT外延薄膜电学性能的影响及其导电机制分析

摘要/Abstract

摘要： 脉冲激光沉积技术制备Ba_0.85Ca_0.15Zr_0.1Ti_0.9O₃(BCZT)外延薄膜时通常需要较高的沉积温度,且易含有氧空位缺陷。本文旨在提供一种基于脉冲激光沉积技术接后退火处理工艺,并成功在导电基板上制备了高质量BCZT外延薄膜,探究了退火温度对BCZT外延薄膜结构和性能的影响。不同温度(750、800、850和900 ℃)退火后薄膜均呈现纯净物相,且随着退火温度的升高,薄膜的铁电性能逐渐提高,2P_r由4.2 μC/cm²提升至17.6 μC/cm²,但900 ℃退火温度下薄膜样品的漏电流问题最严重。通过拟合J-E关系表明,低电场下700 ℃至850 ℃退火后的薄膜均遵循欧姆导电机制,而900 ℃退火后的薄膜遵循空间电荷限制电流机制,高电场下所有退火温度下的薄膜均遵循福勒-诺德海姆隧穿机制。

关键词: 脉冲激光沉积, Ba_0.85Ca_0.15Zr_0.1Ti_0.9O₃外延薄膜, 退火温度, 物相结构, 电学性能, 导电机制

Abstract: The pulsed laser deposition (PLD) technique for the preparation of Ba_0.85Ca_0.15Zr_0.1Ti_0.9O₃(BCZT) epitaxial films usually requires high deposition temperature and is prone to contain oxygen vacancy defects. In order to provide a post-annealing treatment process based on PLD, high-quality BCZT epitaxial films were successfully prepared on conductive substrates, and the effects of annealing temperature on the structure and properties of BCZT epitaxial films were investigated. The films annealed at different temperatures of 750, 800, 850 and 900 ℃ show pure phases. The ferroelectric properties of the films are gradually improved as the annealing temperature increase, with 2P_r increasing from 4.2 to 17.6 μC/cm². However, the sample at the annealing temperature of 900 ℃ has the most serious leakage current problem. By fitting the J-E relationship, it is found that the films annealed from 700 ℃ to 850 ℃ follow the Ohmic conduction mechanism at low fields, while the samples annealed at 900 ℃ follow the space charge limited current mechanism, and all the films follow the Fowler-Nordheim tunneling mechanism at high fields.

Key words: pulsed laser deposition, Ba_0.85Ca_0.15Zr_0.1Ti_0.9O₃ epitaxial film, annealing temperature, phase structure, electrical property, conductivity mechanism

中图分类号:

O484

彭倩文, 吉祥. 退火温度对BCZT外延薄膜电学性能的影响及其导电机制分析[J]. 人工晶体学报, 2024, 53(1): 82-89.

PENG Qianwen, JI Xiang. Effect of Annealing Temperature on Electrical Properties of BCZT Epitaxial Films and Its Conductivity Mechanism[J]. JOURNAL OF SYNTHETIC CRYSTALS, 2024, 53(1): 82-89.

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