Co掺杂对Zn_(1-x)Co_xO稀磁半导体光学性质的影响  

Effects of Co Doping on the Optical Properties of Zn_(1-x)Co_xO Diluted Magnetic Semiconductors

作　　者：郑勇平[1] 张志城[1] 卢宇[1] 黄志南[1] 赖发春[1] 黄志高[1] 

机构地区：[1]福建师范大学物理与光电信息科技学院,福建福州350007

出　　处：《福建师范大学学报（自然科学版）》2007年第5期50-53,共4页Journal of Fujian Normal University：Natural Science Edition

基　　金：国家自然科学基金资助项目(10474037);福建省自然科学基金资助项目(E032002A0510013)

摘　　要：溶胶-凝胶法制备了Co掺杂的ZnO基稀磁半导体,研究其粉体和薄膜的结构和光学特性.X射线衍射结果表明Co2+随机替代Zn2+位置进入ZnO晶格,并引起晶格常数的变化.紫外-可见透射光谱表明样品的禁带宽度随着Co掺杂浓度的增大呈现非单调变化规律,低浓度掺杂样品的光学带隙随掺杂浓度增大而减小(红移),这是由于Co2+替代Zn2+,局域d电子与能带电子之间的sp-d交换耦合引起的.Co doped ZnO-based diluted magnetic semiconductors were prepared by sol-gel method. The structural and optical properties of power and thin film samples were investigated, X-ray diffraction （XRD） patterns show that Co^2＋ ions have substituted the Zn^2＋ ions into ZnO lattice, which results in the changes of lattice constants. The transmission spectra in ultraviolet-visible region indicate that the Co doping has lead to the non-monotonic variation of band gap, The decrease of band gap as Co dopant increases （redshift） for low concentration is attributed to sp-d exchange interaction between located d electrons of Co^2＋ ions substituting the Zn^2＋ ions and the band electrons of the materials.

关 键 词：稀磁半导体 ZnO 溶胶-凝胶法 透射光谱 禁带宽度 

分 类 号：O482.3[理学—固体物理]