Synthesis and characterization of ferromagnetic Zn_{1鈭?span style='font-style: italic'>x}Co_xO films

详细信息	查看全文 | 推荐本文 |

• 作者：S.-Y. Seo^a ; C.-H. Kwak^a ; S.-H. Kim^a ; S.-H. Park^b ; I.-J. Lee^c ; S.-W. Han^d ; ^{shan@jbnu.ac.kr}
• 关键词：A1. Crystal structure ; B1. Zinc compounds ; B2. Magnetic materials ; B2. Semiconducting II&ndash ; VI materials
• 刊名：Journal of Crystal Growth
• 出版年：2012
• 期刊代码：49_00220248
• 类别：ch
• 出版时间：1 May, 2012
• 卷：346
• 期：1
• 页码：56-60
• 文件大小：583 K

摘要

High-quality Zn_1鈭?em>xCo_xO (ZnCoO) thin films with different Co concentrations (x=0鈭?.07) were synthesized on Al₂O₃ substrates using a radio-frequency magnetron sputtering process. The structural, chemical, optical, and electrical properties of the films were characterized using various techniques. High-resolution X-ray diffraction measurements showed that the ZnCoO films had a c-oriented hexagonal wurtzite structure with no extra phases. The lattice constants of the films increased slightly with increasing the Co concentration ratio. X-ray photoelectron spectra show the incorporation of Co²⁺ ions in the ZnO host without the formations of Co clusters. Hall measurements revealed that the films were n-type with a charge carrier density of per cm³. A neutral-donor bound exciton peak (D⁰X) from all specimens was observed at 3.36 eV using photoluminescence measurements at 10 K. The physical and chemical properties of the films suggested that their ferromagnetic properties originated from a direct exchange interaction between magnetic Co ions.