退火气氛对钴掺杂氧化锌稀磁半导体薄膜性能的影响(英文)  

EFFECT OF ANNEALING AMBIENCE ON Co^(2+) DOPED ZnO DILUTED MAGNETIC SEMICONDUCTOR THIN FILMS

作　　者：张磊[1] 徐光亮[1] 魏贤华[1] 刘桂香[1] 赵德友[1] 彭龙[2] 

机构地区：[1]西南科技大学材料学院,四川绵阳621010 [2]电子科技大学微电子与固体电子学院,成都610054

出　　处：《硅酸盐学报》2009年第9期1560-1565,共6页Journal of The Chinese Ceramic Society

基　　金：西南科技大学博士基金(082X0102);四川省教育厅重点(08ZA009)资助项目

摘　　要：用溶胶–凝胶法制备的钴掺杂氧化锌薄膜在不同气氛下退火后均显示室温铁磁性,并且具有不同的载流子浓度。通过对薄膜进行电、磁、光性能及微结构的系统表征,建立了磁性能与载流子浓度之间的关联。研究表明:在氧气和氧氮混合气氛以及氧氩气氛下,退火的样品均具有室温铁磁性。相对于氧氮混合气氛,300K,在无氮气氛退火的样品具有更低的矫顽力,更高的剩磁及大的电子浓度。光致发光谱研究表明:氧氮混合气氛下,退火的样品中存在No受主,这是样品电子浓度及铁磁性下降的原因;因此,体系的铁磁性来源于电子间接机制,使通过控制载流子浓度来调节钴掺杂氧化锌稀磁半导体的铁磁性能成为可能。The room temperature ferromagnetism in Co-doped ZnO films with different carrier concentration fabricated by the sol–gel method at different annealing atmospheres was investigated. The electrical,magnetic,optical,and microstructure properties of these thin films were characterized systematically,and the correlation between magnetic properties and carrier concentration was established. These systems exhibit ferromagnetism at room temperature regardless of the annealing ambience. Comparing with the samples annealed-in an O2-N2 mixed atmosphere at 300K, those annealed without N2 atmosphere have a lower coercive field, higher remanence and larger electron concentration. The lower electron concentration and ferromagnetism in the sample annealed in O2-N2 mixed atmosphere are attributed to the No, which is observed by the photoluminescence spectroscopy. Thus, the magnetism is driven by the electron-mediated ferromagnetism and it is possible to tune ferromagnetism in Co^2＋：ZnO diluted magnetic semiconductors by controlling the carrier concentrations.

关 键 词：氧化锌 溶胶–凝胶法 室温铁磁性 退火气氛 

分 类 号：O482.3[理学—固体物理]