N掺杂对Co-ZnO薄膜电学和磁学性能的影响

doi:10.3724/SP.J.1077.2010.00711

摘要/Abstract

摘要：

采用脉冲激光沉积(PLD)法通过电离活化方式在石英和Si(100)衬底上制备了Co-N共掺ZnO薄膜, 研究了N掺杂对Co-ZnO薄膜电学和磁学性能的影响. 实验观察到700℃、N2O压强为15Pa时生长的Co-N共掺ZnO薄膜显示室温磁滞回线. 采用XRD、SEM、XPS、霍尔测试和SQUID等手段对样品进行了测试, 结果表明, 所得薄膜样品具有高度的c轴择优取向, XRD图谱中并没有发现Co、N的相关分相, Co、N原子分别以替代位形式CoZn、NO存在于薄膜中. 霍尔测试和SQUID测试表明, Co-N共掺ZnO薄膜呈p型, 具有室温磁滞效应. 与Co掺杂ZnO薄膜相比, 载流子浓度降低, 同时, 饱和磁化强度和矫顽力有很大提高, 可见, N的掺入改变了Co掺杂ZnO稀磁半导体薄膜的导电类型, 并增强了磁性.

关键词: PLD, Co-N共掺, ZnO薄膜, 磁性

Abstract:

Co-N co-doped ZnO thin films were fabricated on quartz and Si(100) substrates using a technique of electron cyclotron resonance (ECR) N₂O plasma-enhanced pulsed laser deposition and studied the influence of N dopant on the electric and magnetic properties of Co doped ZnO thin films. The thin films deposited at 700℃ and N₂O pressure of 15Pa had magnetism at room temperature. The samples were tested by XRD, SEM, XPS, Hall testing and superconducting quantum interference device (SQUID) magnetometry. The results indicate that the configuration of the thin films is a completely c-axis orientation without any Co or N related phases. Co atoms and N atoms substitute Zn and O sites respectively in the form of Co_Znand N_O in the thin films. Hall testing and SQUID results indicate that Co-N co-doped thin films are p type with lower carrier concentration and higher magnetization than those of the Co doped ZnO thin films. The N dopant changes the conduction type and gives rise to the increasing of magnetization of Co doped ZnO thin films.

Key words: PLD, Co-N co-doping, ZnO thin films, magnetism

中图分类号:

O472

王雪涛, 朱丽萍, 叶志高, 叶志镇, 赵炳辉. N掺杂对Co-ZnO薄膜电学和磁学性能的影响[J]. 无机材料学报, 2010, 25(7): 711-716.

WANG Xue-Tao, ZHU Li-Ping, YE Zhi-Gao, YE Zhi-Zhen, ZHAO Bing-Hui. Influence of N Dopant on the Electric and Magnetic Properties of Co Doped ZnO Thin Films[J]. Journal of Inorganic Materials, 2010, 25(7): 711-716.

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