磁场调控钙钛矿结构多铁性薄膜材料的制备与物性研究

项目名称： 磁场调控钙钛矿结构多铁性薄膜材料的制备与物性研究

项目编号： No.10874051

项目类型： 面上项目

立项/批准年度： 2009

项目学科： 金属学与金属工艺

项目作者： 戴建明

作者单位： 淮北师范大学

项目金额： 35万元

中文摘要： 多铁性材料兼具有磁和铁电有序，不仅在新型多功能器件应用具有广阔的前景，而且由于这一体系自身具有丰富的结构和电子相图以及多种序参量的耦合相互作用等基本物理问题，多年来引起人们极大的研究兴趣。本项目研究主要以钙钛矿结构多铁性材料BiFeO3（BFO）及其掺杂化合物为研究对象，采用化学溶液沉积（CSD）等方法结合磁场下的材料合成与退火热处理技术，开展了系统的材料制备与物性调控等方面研究，取得的重要研究结果有：1）利用水冷磁体研制了磁场下的高温热处理装置，可用于0-0.8T磁场强度1100℃#39640;温下的材料合成与热处理。2）通过改变CSD制备工艺，研究了BiFeO3薄膜的磁电性质的单层厚度效应、薄膜总厚度效应等，认识了制备工艺、微结构以及对磁、电性质的影响与物理机制。3）研究了磁场条件下制备BFO及其掺杂化合物以及磁电复合薄膜的微结构、畴结构及其磁场对样品磁、电性能的调控作用与机理，获得了磁电性能增强的多铁性薄膜材料。项目研究工作为寻找提高多铁性材料磁电性能的有效途径，加深理解钙钛矿结构多铁性材料中多种相互作用的机制以及进一步开展磁电功能薄膜材料的磁场下制备与物性调控研究工作提供了实验基础。

中文关键词： 钙钛矿结构；多铁性；化学溶液沉积；磁场退火；磁电效应

英文摘要： In recent years the multiferroic materials, which have both magnetic and ferroelectric order, have attracted intensive interest not only because of the broad prospects in the application of new multi-function devices, but also because of the rich structural and electronic phase diagram, as well as magnetic, electrical and its couple interaction in the system. In this research project, we focus on the multiferroic BiFeO3 (BFO) and its doped compounds, by using chemical solution deposition (CSD) and other methods combining with the magnetic field annealing heat treatment technology. The important research results as follows: 1) A special magnetic field annealing equipment has been developed by using water-cooling magnet, which can be employed to synthesize materials and heat treatment under magnetic field of 0-0.8T and high temperature of 1100℃ 2) The individual-layer thickness effects, total thickness effects on magnetic, dielectric, ferroelectric, and magnetoelectric properties of BFO films by changing the CSD process, are investigated in detail. The relations between the parameters of process, microstructures, and physical properties are understood more clearly. 3) The effects of magnetic annealing on the microstructure, magnetic, dielectric, ferroelectric properties, as well as magnetoelectric coupling effect of the BFO and BFO-based composite thin films are investigated. It is confirmed that the magnetic-electric properties can be improved by magnetic field annealing.The research results in this project are beneficial to understand physical mechanism of the magneto-electric orderliness and its coupling interaction. It is also important to prepare other magnetic-electric function materials and modulate the physical preperties by using magnetic field annealing.

英文关键词： Perovskite structure; Multiferroic; Chemical solution deposition; Magnetic field annealing; Magnetoelectric effect