缓冲层和退火气氛对Cu掺杂ZnO薄膜稀磁性的影响

摘要

采用直流与射频双靶共溅射的方法在石英衬底上制备Cu掺杂的ZnO薄膜。利用X射线衍射(XRD)、扫描电子显微镜(SEM)、霍尔测试仪(HALL8800)以及超导量子干涉仪(SQUID)分别对样品的结构、表面形貌、电学特性和磁性进行表征，研究了AZO缓冲层以及不同气氛下退火处理对薄膜磁性的影响。结果表明，加入缓冲层的样品结晶质量有所改善，但不利于磁性的产生；空气退火使样品中氧空位大量减少，同时磁性减弱；真空退火使样品中氧空位得以保留，磁性增强，氧空位缺陷对磁性的产生有很大贡献。样品中载流子浓度不高，电阻率较大，载流子浓度对样品磁性的影响不明显。%By mean of DC and RF co-sputtering, Cu-doped ZnO films were deposited on quartz substrates, followed by subsequently annealing in different atmospheres. The structures, surface appearances, electrical properties and magnetism were characterized with X-ray diffraction (XRD), scanning electron microscope (SEM), Hall effect measurement and superconducting quantum interference device (SQUID), respectively. The result demonstrates that buffer layers can improve crystallization, but block generation of magnetism. Air annealing treatment reduces oxygen vacancy within the samples significantly, while weakening magnetism. Vacuum annealing treatment preserves oxygen vacancy and resultantly strengthens magnetism. Oxygen vacancy defects have great contribution to generation of magnetism. Carrier concentrations of all samples are low and resistivity is relatively high. Also, carrier concentration has no obvious effect on magnetism of the samples.