Perpendicular-anisotropy CoFeB-MgO based magnetic tunnel junctions scaling down to 1X nm

CoFeB-MgO based magnetic tunnel junction with perpendicular easy axis (p-MTJ) shows a high potential to be used in spintronics based very large scale integrated circuits and spin-transfer-torque magnetorestive random access memories. In this paper, we review development of p-MTJ using single CoFeB-MgO and double CoFeB-MgO interface structures. The TMR ratio shows 164% after annealing at 400 °C, indicating the CoFeB-MgO p-MTJs have capability for back-end-of-line. Scaling properties of p-MTJs using double CoFeB-MgO interface structure are also reviewed.

[1]  Andrew G. Glen,et al.  APPL , 2001 .

[2]  Bernard Rodmacq,et al.  Crossover from in-plane to perpendicular anisotropy in Pt/CoFe/AlOx sandwiches as a function of Al oxidation: A very accurate control of the oxidation of tunnel barriers , 2002 .

[3]  P. L. Trouilloud,et al.  Magnetoresistance measurement of unpatterned magnetic tunnel junction wafers by current-in-plane tunneling , 2003 .

[4]  Bernard Rodmacq,et al.  Analysis of oxygen induced anisotropy crossover in Pt/Co/MOx trilayers , 2008 .

[5]  H. Ohno,et al.  Fabrication of a Nonvolatile Full Adder Based on Logic-in-Memory Architecture Using Magnetic Tunnel Junctions , 2008 .

[6]  S. Ikeda,et al.  2 Mb SPRAM (SPin-Transfer Torque RAM) With Bit-by-Bit Bi-Directional Current Write and Parallelizing-Direction Current Read , 2008, IEEE Journal of Solid-State Circuits.

[7]  S. Yuasa,et al.  Influence of perpendicular magnetic anisotropy on spin-transfer switching current in CoFeB∕MgO∕CoFeB magnetic tunnel junctions , 2009 .

[8]  Bernard Rodmacq,et al.  Pt/Co/oxide and oxide/Co/Pt electrodes for perpendicular magnetic tunnel junctions , 2009 .

[9]  Shoji Ikeda,et al.  A 32-Mb SPRAM With 2T1R Memory Cell, Localized Bi-Directional Write Driver and `1'/`0' Dual-Array Equalized Reference Scheme , 2010, IEEE Journal of Solid-State Circuits.

[10]  H. Ohno,et al.  A perpendicular-anisotropy CoFeB-MgO magnetic tunnel junction. , 2010, Nature materials.

[11]  Shoji Ikeda,et al.  Properties of magnetic tunnel junctions with a MgO/CoFeB/Ta/CoFeB/MgO recording structure down to junction diameter of 11 nm , 2014 .

[12]  Naoki Fukuda,et al.  Energy resolution of gas ionization chamber for high-energy heavy ions , 2013 .