摘要铁电材料具有自发极化与极化反转的特性,且具有较高的介电常数与显著的热释电、压电效应,被广泛应用于多个领域。而铁酸铋BiFeO3作为目前有可能在高温下使用的铁电材料已经进入研究人员的视野而被广泛研究。33538
本论文中主要工作:利用脉冲激光沉积法(PLD)在SrTiO3基片成功制备出BiFeO3薄膜。通过薄膜样品的AFM图,观察到薄膜的表面起伏较小,晶粒比较均匀,薄膜质量较好。通过薄膜样品的XRD谱可以确定长出的是BiFeO3薄膜。利用压电响应力显微镜(PFM)观察到薄膜样品有明显的畴结构,说明所制备的薄膜样品具有良好的铁电和压电性。通过薄膜样品的I-V特性曲线可以观察的到BiFeO3薄膜具有较明显的光伏效应。
通过一系列的数据分析和研究,我们对BiFeO3薄膜有了初步的了解,这为我们进一步探索BiFeO3薄膜打下了坚实的基础。
关键词 铁电材料 铁电体 BiFeO3 PLD XRD AFM PFM 畴光伏效应
毕业设计说明书(毕业论文)外文摘要
Title The Preparation and Semiconducting Characterizations of the Perovskite Ferroelectric Thin Film
Abstract
Ferroelectric materials, possess the characteristics of spontaneous polarization,polarization reversal,high dielectric constant, outstanding pyroelectric properties and piezoelectric effect, thus they are the hot topics in recent research and promising to be utilized in many areas. BiFeO3 is a ferroelectric material, which can be used at high temperature. This material is highly concerned and extensively studied recently .
In this paper, smooth BiFeO3 thin films were prepared successfully on SrTiO3 substrates by Pulsed Laser Deposition. AFM diagrams of the film samples confirmed that the surface membranes of the films are smooth and consist better quality. XRD spectra varified that the samples are of BiFeO3 films. Furthermore, significant domain structures were observed by PFM images and it was proved that the film samples have good ferroelectric and piezoelectric properties. We can observe obvious Photovoltaic effect by I-V characteristic curve of films.
Through series of analysis and research to the data, we have a preliminary understanding of the BiFeO3 film, which has laid solid foundation for us to explore BiFeO3 film.
Keywords Ferroelectric BiFeO3 PLD XRD AFM PFM domain
Photovoltaic effect
目 次
1 引言 1
1.1 铁电体概述 1
1.1.1 铁电体 1
1.1.2 铁电体的分类 2
1.1.3 铁电体的主要应用 2
1.1.4 BiFeO3介绍 3
1.1.5 BiFeO3的研究现状 4
2 薄膜的制备与表征 5
2.1 制备工艺-脉冲激光沉积法(PLD) 5
2.1.1 脉冲激光溅射沉积法(PLD)的工作原理 5
2.1.2 PLD 法研究BiFeO3 薄膜的进展 7
2.2 主要表征设备的工作原理 7
2.2.1 AFM(原子力显微镜)工作原理 7
2.2.2 PFM(压电响应力显微镜)的工作原理 8
2.3 脉冲激光沉积法(PLD)制备BiFeO3薄膜 9
2.3.1 实验原料与器材 9
2.3.2 实验步骤 10
3 BiFeO3薄膜的电光性质研究 12
3.1 BiFeO3薄膜的XRD分析 12
3.2 BiFeO3 薄膜的表面形貌分析 13
3.3 BiFeO3薄膜的铁电、压电性能分析 14
3.4 BiFeO3薄膜的光电性能分析 18 通过晶格严重畸变和电畴精细调控探索BiFeO3的多铁和半导体性能:http://www.751com.cn/cailiao/lunwen_30697.html