Realization of Magnetic RAM using Magnetic Tunneling Junction in atomic level

Abstract

Magnetic RAM (MRAM) is the non-volatile memory device with excellent endurance. Magnetic Tunneling Junction (MTJ) is the basic building block of the MRAM which is used to store information extracting the two-valued resistance property. With the discovery of Giant Magneto Resistance effect (GMR) and Tunnel Magneto Resistance effect (TMR) phenomenon in the magnetic multilayer of MTJ, the difference between the two resistances is distinct. Writing in MTJ can be carried with superior speed, low power using Spin Transfer Torque (STT) writing technique. The parallel and anti-parallel configurations of the MTJ can be carried out by manipulating the spin of the electrons of the magnetic multilayer. In this paper, we have modelled the Fe-MgO-Fe MTJ in atomic level using the software Atomistix ToolKit (ATK) Virtual NanoLab (VNL) 2008.10. We have analysed the V-I characteristics of the MTJ for the various bias voltages and have obtained the resistance of 5.2 MΩ and 55.7 MΩ for the parallel and anti-parallel configurations respectively. This difference in the two resistances holds good to differentiate the data `0' or `1' stored in the MTJ. The TMR thus calculated is around 950%. Higher the TMR ratio lower is the Resistance Area (RA) product.