真空退火对ZnMnO：N物理特性影响的研究  

Study of influence of the vacuum annealing on physical properties of ZnMnO:N

作　　者：孙霞[1] 吴孔平[1] 顾书林[2] 黄时敏[2] 朱顺明[2] 

机构地区：[1]安徽理工大学电气与信息工程学院,淮南232001 [2]南京大学电子科学与工程学院,南京210093

出　　处：《中国科学：物理学、力学、天文学》2012年第5期498-504,共7页Scientia Sinica Physica,Mechanica & Astronomica

基　　金：国家自然科学基金(批准号:60990312,61025020);国家高技术研究发展计划(编号:2007AA03Z404);安徽省自然科学基金(编号:12080850F116)资助项目

摘　　要：利用金属有机源化学气相沉积(MOCVD)技术,在蓝宝石上外延了Mn-N共掺ZnO薄膜,同时,将得到的ZnMnO:N样品分别在700,900和1100°C的温度下进行真空退火处理.X射线衍射(XRD)显示真空退火使薄膜样品的晶格质量变差,但样品都具有良好的单轴取向.ZnMnO:N样品的拉曼光谱(Raman)和光致发光谱(PL)光学表征显示真空退火使得样品中氧空位(VO)增多.对NT,Mn共掺ZnO晶体的第一性原理模拟计算揭示了N,Mn共掺ZnO的态密度存在较强的p-d相互作用,产生磁矩.一旦引入氧空位(VO)后,费米能级上移,p-d相互作用消失,磁矩减小甚至消失.实验表征分析与模拟计算结果一致:对于N,Mn共掺ZnO薄膜样品,引入氧空位(VO)后,铁磁性减弱.因此,Mn3d电子与N2p局域束缚的电子形成的磁性束缚激子(BMP)决定了磁性相互作用的产生.Mn-N co-doped ZnO film on sapphire substrate was fabricated by metal-organic chemical vapor deposition （MOCVD） method, and the sample was annealed in vacuum under temperature 700℃, 900℃ and 1100℃, respectively. X-ray diffraction （XRD） displayed the vacuum annealing make the sample deteriorated, but showed the strong c-axis orientation. Raman and PL have been employed to analyze crystal qualities show the vacuum annealing makes oxygen vacancies （Vo） increased. The first principle of simulation calculation for Mn and N codoped ZnO crystals have achieved, and the total density of states reveals the strong p-d interaction and existing magnetic moment in the Mn and N codoped ZnO. Once the introduction of oxygen vacancies （Vo）, the Fermi energy would be moved up, which resulted in p-d interaction disappear and magnetic moment reduced even disappeared. Therefore, the formation of magnetic bound polaron （BMP） of Mn 3d electronics and N 2p local bound electronic determines the magnetic interaction effects, which can be explained from the theoretical predication on the Mn 3d and N 2p ferromagnetic （hole） coupling on the ferromagnetism.

关 键 词：稀磁半导体  磁化  第一性原理 Mn-N共掺ZnO 

分 类 号：TN304.055[电子电信—物理电子学]