Defect induced ferromagnetism in Co-doped ZnO thin films

被引：22

作者：

Fonin, M. ^{[1
]}

Mayer, G. ^{[1
]}

Biegger, E. ^{[1
]}

Janssen, N. ^{[1
,2
]}

Beyer, M. ^{[1
,2
]}

Thomay, T. ^{[1
,2
]}

Bratschitsch, R. ^{[1
,2
]}

Dedkov, Yu S. ^{[3
]}

Ruediger, U. ^{[1
]}

机构：

[1] Univ Konstanz, Fachbereich Phys, D-78457 Constance, Germany

[2] Ctr Appl Photon, D-78457 Constance, Germany

[3] Tech Univ Dresden, Inst Festkorperphys, D-01062 Dresden, Germany

来源：

PROCEEDINGS OF THE 17TH INTERNATIONAL VACUUM CONGRESS/13TH INTERNATIONAL CONFERENCE ON SURFACE SCIENCE/INTERNATIONAL CONFERENCE ON NANOSCIENCE AND TECHNOLOGY | 2008年 / 100卷

关键词：

D O I：

10.1088/1742-6596/100/4/042034

中图分类号：

TB3 [工程材料学];

学科分类号：

0805 ; 080502 ;

摘要：

We present a study on the structural, magnetic, and optical properties, as well as the electronic structure of Co-doped ZnO films prepared by magnetron sputtering. Magnetization measurements performed at different temperatures indicate ferromagnetic and paramagnetic behavior for the samples prepared at oxygen-poor conditions whereas the samples prepared at oxygen-rich conditions show only paramagnetic behavior corroborating that the presence of oxygen-related defects is essential for ferromagnetism in Zn1-xCoxO. Xray absorption spectroscopy (XAS) at the Co L-2,L-3 edge together with optical transmittance measurements show that Co ions are present in the high-spin Co2+ (d(7)) state under tetrahedral symmetry indicating a proper incorporation in the ZnO host lattice. Comparison of the O K edge XAS spectra of the samples prepared at different conditions show substantial changes in the spectral line shape which are attributed to the presence of lattice defects such as oxygen vacancies in the ferromagnetic oxygen-poor Co-doped ZnO samples. Our findings indicate that the ferromagnetic properties of Co-doped ZnO samples are strongly correlated with the presence of oxygen vacancies in the ZnO lattice supporting the spin-split impurity band model.

引用

页数：4

共 22 条

[1] Comparison of the electronic structures of Zn1-xCoxO and Zn1-xMgxO nanorods using x-ray absorption and scanning photoelectron microscopies [J].