Spin transfer switching in TbCoFe/CoFeB/MgO/CoFeB/TbCoFe magnetic tunnel junctions with perpendicular magnetic anisotropy
Spin transfer switching in TbCoFe/CoFeB/MgO/CoFeB/TbCoFe magnetic tunnel junctions with perpendicular magnetic anisotropy
复制标题
DOI：
10.1063/1.2838335
复制
发表时间：
2008-04-01
影响因子：
3.2
通讯作者：
Yoda, Hiroaki
中科院分区：
文献类型：
--
作者：
Nakayama, Masahiko;Kai, Tadashi;Yoda, Hiroaki
研究了TbCoFe/CoFeB/MgO/CoFeB/TbCoFe磁性隧道结（MTJ）的自旋转移（ST）开关。TbCoFe/CoFeB自由层在室温下具有1.2kOe的大矫顽场和107的大热稳定因子，通过100 ns的脉冲电流以4.7MA/cm（2）的电流密度进行开关。这是第一次报告的ST开关在MTJ与垂直磁各向异性。还研究了矫顽场的温度依赖性，以估计由于焦耳热效应而升高温度的情况下的磁各向异性。在开关脉冲电流期间的模拟温度87 ℃下测得的矫顽场约为0.34kOe。在具有TbCoFe/CoFeB自由层的MTJ中的开关电流密度与在开关电流下的矫顽场的比率小于具有面内磁化CoFeB自由层的典型MTJ中的开关电流密度与矫顽场的比率。这一结果表明，具有垂直磁各向异性的MTJ有利于实现低开关电流的磁阻随机存取存储器。(c)2008年美国物理研究所。
Spin transfer (ST) switching in the TbCoFe/CoFeB/MgO/CoFeB/TbCoFe magnetic tunnel junction (MTJ) was studied. The TbCoFe/CoFeB free layer with a large coercive field of 1.2 kOe and a large thermal stability factor of 107 at room temperature was switched by a 100 ns pulse current with a current density of 4.7 MA/cm(2). This is the first report of ST switching in a MTJ with perpendicular magnetic anisotropy. The temperature dependence of the coercive field was also investigated to estimate the magnetic anisotropy in the case of rising temperature due to the Joule heating effect. The measured coercive field at 87 degrees C, which was the simulated temperature during the switching pulse current, was about 0.34 kOe. The ratio of the switching current density to the coercive field under the switching current in the MTJ with the TbCoFe/CoFeB free layer is smaller than that in a typical MTJ with an in-plane magnetized CoFeB free layer. This result indicates that a MTJ with perpendicular magnetic anisotropy is advantageous for realizing low switching current magnetoresistive random access memory. (c) 2008 American Institute of Physics.