Japanese Journal of Applied Physics · 2012 · 15 citations · 10 references
Natural SciencesElectrical EngineeringMaterials ScienceElectronic MaterialsMagnetic MaterialsMicroelectronicsMagnetic CharacterizationMagnetic Circuit AnalysisMagnetic Properties Of SolidsMagnetic Recording MaterialsSpintronicsCurrent-induced Magnetization SwitchingMagnetic ModelingMagnetic Tunnel JunctionsMagnetic Tunneling JunctionsSpin-transfer TorqueSwitching SpeedTime-resolved DynamicsTransit Time Effects
The time-resolved switching characteristics of 100×200 nm2 size CoFeB/MgO/CoFeB-based magnetic tunnel junction (MTJ) are investigated by using the 20 GHz sampling measurement technique. We focused on the physical quantities of the time-resolved characteristics such as incubation time tA, transit time tB, and the standard deviations σV's of the period of the switching waveform. Furthermore, the dependencies of tA and tB on the applied pulse waveforms are analyzed. We found tA exponentially decreases as the applied voltage to MTJ increases, while tB remains less than two nano seconds regardless of the applied voltage. Furthermore, it is observed that the standard deviations of the waveform during tA is larger than that of the other periods. Finally, we discuss the switching characteristics with proposed toy model based on spin transfer torque (STT) phenomena.
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