The Effect of Interface Texture on Exchange Biasing in Ni80Fe20/Ir20Mn80System

Abstract

Exchange-biasing phenomenon can induce an evident unidirectional hysteresis loop shift by spin coupling effect in the ferromagnetic (FM)/antiferromagnetic (AFM) interface which can be applied in magnetoresistance random access memory (MRAM) and recording-head applications. However, magnetic properties are the most important to AFM texturing. In this work, top-configuration exchange-biasing NiFe/IrMn(x Å) systems have been investigated with three different conditions. From the high-resolution cross-sectional transmission electron microscopy (HR X-TEM) and X-ray diffraction results, we conclude that the IrMn (111) texture plays an important role in exchange-biasing field (Hex) and interfacial exchange energy (Jk).HexandJktend to saturate when the IrMn thickness increases. Moreover, the coercivity (Hc) dependence on IrMn thickness is explained based on the coupling or decoupling effect between the spins of the NiFe and IrMn layers near the NiFe/IrMn interface. In this work, the optimal values forHexandJkare 115 Oe and 0.062 erg/cm2, respectively.

Effect of grain size on magnetic and nanomechanical properties of Co60Fe20B20 thin films

“…Magnetic CoFeB, Co, or NiFe thin film can be inserted as a free and/or pinned layer into the MTJ device, as it has a high spin tunneling efficiency and its spin-valve structure exhibits ferromagnetism (FM)/antiferromagnetism (AFM) exchange-biasing anisotropy [7][8][9][10]. Moreover, the favorable characteristics of the MTJ device, including high tunneling magnetoresistance (TMR), strength, and durability, are critical to operation of an MTJ device at room temperature (RT) and in high-temperature environments [11,12].…”

Effect of Ta buffer and NiFe seed layers on pulsed-DC magnetron sputtered Ir20Mn80/Co90Fe10 exchange bias

“…Series of EB system were prepared onto Si/1000 nm thermal SiO 2 substrates using the Pulsed DC magnetron sputtering technique at Ar gas pressures of 2-3 mTorr, resulting in the following layer sequences: Ta(t b )/Ni 81 Fe 19 ( chosen as 10 nm, since at this thickness the exchange anisotropy constant and exchange bias for top NiFe/IrMn and bottom IrMn/ CoFe based EB systems was reported to be the largest [23,24]. The base pressure prior to the deposition was the order of 2 Â 10 À 9 Torr and the target materials had a purity of 99.9%.…”

Tunneling magnetoresistance of perpendicular CoFeB-based junctions with exchange bias

“…On the other hand, the presence of B at the interface of CoFeB/MgO is detrimental to TMR 14 because it suppresses the conductance through the band of ∆ 1 symmetry, which is known to be responsible for high TMR in epitaxial CoFe/MgO/CoFe (001) 15 . Therefore, 17 and MgO films were deposited from elemental and composite targets. The purity of all targets was 99.9% or higher.…”