物理化学学报 >> 2007, Vol. 23 >> Issue (04): 493-498.doi: 10.3866/PKU.WHXB20070408

研究论文 上一篇    下一篇

自旋阀多层膜的电化学制备及其巨磁电阻效应

姚素薇;姜莹;张卫国   

  1. 天津大学化工学院杉山表面技术研究室, 天津 300072
  • 收稿日期:2006-09-13 修回日期:2006-11-14 发布日期:2007-04-05
  • 通讯作者: 姚素薇 E-mail:yaosuwei@263.net

Electrochemical Preparation and Giant Magnetoresistance Effect of Spin-valve Multilayers

YAO Su-Wei; JIANG Ying; ZHANG Wei-Guo   

  1. SUGIYAMA Laboratory of Surface Technology, School of Chemical Engineering and Technology, Tianjin University, Tianjin 300072, P. R. China
  • Received:2006-09-13 Revised:2006-11-14 Published:2007-04-05
  • Contact: YAO Su-Wei E-mail:yaosuwei@263.net

摘要: 采用双槽控电位电沉积法在n-Si(111)基体上以NiFe 薄膜为缓冲层制备了[Ni80Fe20/Cu/Co/Cu]n自旋阀多层膜, 并确定了电沉积的工艺条件. 利用X射线衍射(XRD)表征了自旋阀多层膜的超晶格结构, 研究了NiFe缓冲层对自旋阀生长取向的影响. 采用四探针法研究了各子层厚度对自旋阀巨磁电阻效应的影响, 通过振动样品磁强计(VSM)测试了自旋阀的磁滞回线. 自旋阀的巨磁电阻(GMR)值最初随着铜层厚度的变化并发生周期性振荡, Cu 层厚度为3.6 nm时, GMR 达到最大值,随后逐渐减小. 随着Co层和NiFe 层厚度的增大, GMR 值的变化趋势均为先增大后减小. 当自旋阀的结构为NiFe(25 nm)/[Cu(3.6 nm)/Co(1.2 nm)/Cu(3.6 nm)/NiFe(2.8 nm)]30时, GMR 值可达5.4%, 对应的磁电阻灵敏度(SV)为0.2%·Oe-1, 饱和磁场仅为350 Oe.

关键词: 自旋阀, 多层膜, 电沉积, 巨磁电阻, 超晶格

Abstract: [Ni80Fe20 /Cu/Co/Cu]n spin-valve multilayers were fabricated onto n-Si(111) substrates covered with NiFe buffer layers by means of double bath potentiostatic electrodeposition. The electrochemical conditions were determined. A well-defined superlattice structure was characterized by high-angle X-ray diffraction, and the influence of NiFe buffer layer upon the orientation of crystalline growth was studied. Magneto-transport properties of the spin valves were investigated by four-probe technique. Hysteresis loops were tested by vibrating sample magnetometer (VSM) at room temperature. With the increase of the Cu layer thickness (tCu), giant magnetoresistance(GMR) ratio showed a periodical oscillation at first and achieved the maximum at tCu=3.6 nm, then declined gradually. With the increase of the Co and NiFe layer thickness, GMR ratio rose at first, and dropped after the peak point. The maximum room temperature GMR ratio of 5.4%was obtained with a sensitivity up to 0.2%·Oe-1 and a saturation field of 350 Oe for NiFe(25 nm)/[Cu(3.6 nm)/Co(1.2 nm)/Cu(3.6 nm)/NiFe(2.8 nm)]30 structures.

Key words: Spin-valves, Multilayers, Electrodeposition, Giant magnetoresistance, Superlattice

MSC2000: 

  • O646