摘要稀磁半导体（DMSs）材料同时利用了电子的电荷和自旋属性，具有优异的磁、磁光、磁电等性能，因此在材料科学和自旋电子器件领域具有广阔的应用前景。近年来，采用磁性离子注入技术，发现了ZnO半导体在室温下具有铁磁有序性。基于ZnO稀磁半导体在自旋电子器件方面的潜在应用价值，推动了国内外材料研究工作者的广泛研究，其中Co掺杂ZnO基稀磁半导体的研究尤其引起了许多人的关注，但实验对其铁磁性的来源还存在诸多争议。本课题采用超声喷雾热解法(USP)制备Co掺杂ZnO稀磁薄膜样品，并采用X射线衍射（XRD）、X射线光电子能谱（XPS）和超导量子干涉（SQUID）等测试手段研究其结构和磁性能，进而讨论其磁性来源。实验发现，单独Co的样品中铁磁性是是因为材料中出现了某种顺磁相，而N-Co共掺的样品的铁磁性是来源于空穴为媒介的束缚磁极化子。39024
毕业论文关键字：Co掺杂，超声喷雾热解法，ZnO薄膜,稀磁半导体，铁磁性
Abstract  Diluted magnetic semiconductors (DMSs) materials make use of charge and spin properties of electrons at the same time, and it has a broad application prospect in the field of spin electronic devices and materials science, due to its excellent magnetic,magneto-optical, and magnetic-electric properties. In recent years, by using the magnetic ion injection technology, it has been found that ZnO semiconductor has a ferromagnetic ordering at room temperature. In the whole world, many material researchers have made great efforts to research transition-mental doped ZnO due to their potential application in spintronics, and the study of Co-doped ZnO-based DMSs has especially aroused many people’s attention, however there exists still a lot of disputes on the origin of room temperature ferromagnetism in ZnO system. In this paper, we have prepared the Co-doped ZnO diluted magnetic thin films by a simple chemical vapor deposition method, i.e., ultrasonic spray pyrolysis (USP) technique. The structure and magnetic properties were explored by the X-ray diffraction (XRD), X-ray photoelectron pectroscopy (XPS) and superconducting quantum interference (SQUID), and then the origin of magnetism was discussed. By experimental analysis, it is considered that the ferromagnetism in Co-doped ZnO films results from the paramagnetic phase, while the magnetic property in N-Co doped ZnO films originates from the hole-mediated bound magnetic polarons.
Key words: Co doping, ultrasonic spray pyrolysis (USP), ZnO thin films, diluted magnetic semiconductors (DMSs), ferromagnetism
目录
1.绪论
1.1 引言    4
1.2 研究背景和意义    4
1.3 ZnO晶体结构和物理特征    5
1.3.1 ZnO 的晶体结构    5
1.3.2 ZnO的电学特性    6
1.3.3 ZnO的光学特性    6
1.4 ZnO稀磁掺杂体系的研究进展    7
1.4.1 Co掺杂体系    7
1.4.2 Mn掺杂体系    8
1.5 ZnO薄膜的制备方法    8
1.5.1 分子束外延（MBE）    8
1.5.2 脉冲激光沉淀法（PLD）    8
1.5.3 化学气相沉淀法（MOCVD）    9
1.5.4 溅射法    10
1.5.5溶胶-凝胶法（gol-gel）    10
1.5.6喷雾热解法（SP）    11
1.6 选题依据    11
1.6.1选题依据    11
1.6.2 主要研究内容    11
2.1 材料制备方法    12
2.2 性能表征手段    13
2.2.1 X射线衍射分析(XRD)    14
2.2.2 XPS    14
2.2.3 光致发光光谱PL    14
2.2.4　超导量子干涉仪（SQUID）    14 Co掺杂稀磁性ZnO薄膜的制备:http://www.751com.cn/cailiao/lunwen_38120.html