硅酸盐学报

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)

作者：张磊徐光亮魏贤华刘桂香赵德友彭龙

关键词：氧化锌溶胶–凝胶法室温铁磁性退火气氛

分类号：O484.4

出版年,卷(期):页码：2009,37(9):1560-1565

DOI：

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 300 K,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 Co2+:ZnO diluted magnetic semiconductors by controlling the carrier concentrations.

基金项目：

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

作者简介：

参考文献：

[1] GREGG J F, ALLEN W D, VIART N R, et al. The art of sp↑n elec- tron↓cs [J]. J Magn Magn Mater, 1997, 175(1): 1–9. [2] OHNO Y, YOUNG D K, BESCHOTEN B, et al. Electrical spin injec- tion in a ferromagnetic semiconductor heterostructure [J]. Nature, 1999, 402(52): 790–792. [3] DIETL T, OHNO H, MATSUKURA F, et al. Zener model description of ferromagnetism in zinc-blende magnetic semiconductors [J]. Science, 2000, 287(11): 1019–1022. [4] RODE K, ANANE A, MATTANA R, et al. Magnetic semiconductors based on cobalt substituted ZnO [J]. J Appl Phys, 2003, 93(10): 7676– 7678. [5] LEE H J, JEONG S Y, CHO C R, et al. Study of diluted magnetic semiconductor: Co-doped ZnO [J]. Appl Phys Lett, 2002, 81(21): 4020–4022. [6] JIN Z, FUKUMURA T, KAWASAKI M, et al. High throughput fabri- cation of transition-metal-doped epitaxial ZnO thin films: a series of oxide-diluted magnetic semiconductors and their properties [J]. Appl Phys Lett, 2001, 78(24): 3824–3827. [7] KIM J H, KIM H, KIM D, et al. Magnetic properties of epitaxially grown semiconducting Zn1–xCoxO thin films by pulsed laser deposition [J]. J Appl Phys, 2002, 92(10): 6071–6069. [8] RAMACHANDRAN S, TIWARI A, NARAYAN J. Zn0.9Co0.1O-based diluted magnetic semiconducting thin films [J]. Appl Phys Lett, 2004, 84(25): 5255–5257. [9] RAMACHANDRAN S, TIWARI A, NARAYAN J, et al. Epitaxial growth and properties of Zn1–xVxO diluted magnetic semiconductor thin films [J]. Appl Phys Lett, 2005, 87(17): 172502. [10] KIM D H, WANG J S, LEE K W, et al. Formation of Co nanoclusters in epitaxial Ti0.96Co0.04O2 thin films and their ferromagnetism [J]. Appl Phys Lett, 2002, 81(13): 2421–2423. [11] YAO B, SHEN D Z, ZHANG Z Z, et al. Effects of nitrogen doping and illumination on lattice constants and conductivity behavior of zinc oxide grown by magnetron sputtering [J]. J Appl Phys, 2006, 99(12). 123510. [12] KERVALISHVILI P, LAGUTIN A. Nanostructures, magnetic semi- conductors and spintronics [J]. Microelectronics J, 2008, 39(8): 1060– 1065. [13] LOOK D C, HEMSKY J W, SIZELOVE J R. Residual native shallow donor in ZnO [J]. Phys Rev Lett, 1999, 82(12): 2552–2555. [14] ZHOU J, SU D G, AHONG M F. Characterization of nanometer-sized ZnO particles by solvothermal method [J]. New Chem Mater (in Chi- nese), 2008, 36(3): 50–52. [15] XIAO Zhiyan. The preparation and the investigation of electrical and optical properties of nitrogen-doped p-type ZnO (in Chinese, disserta- tion). Changchun: Institute of Optics and Fine Mechanics and Physics, 2006. [16] PARK C H, ZHANG S B, WEI S H. Origin of p-type doping difficulty in ZnO: the impurity perspective [J]. Phys Rev B, 2002, 66(7): 073202. [17] VANHEUSDEN K, WARREN W L, SEAGER C H, et al. Mechanisms behind green photoluminescence in ZnO phosphor powders [J]. J Appl Phys, 1996, 79(10): 7983–7990.

服务与反馈：

【文章下载】【加入收藏】