Advanced 18 nm Quad-MTJ technology overcomes dilemma of Retention and Endurance under Scaling beyond 2X nm

摘要

Advanced quad-interfaces perpendicular magnetic tunnel junction (Quad-MTJ) was developed by engineering a low effective damping constant (αeff) material in free layer with high perpendicular magnetic anisotropy (PMA), and low resistance area product (RA) in MgO layers, and stable reference layer. The advanced 18 nm Quad-MTJ fabricated by the developed low-damage 300 mm fabrication process exhibited following performances over those of Double-MTJ; (a) 1.77 times larger thermal stability factor (Δ), (b) 0.83 times smaller writing current (Ic) at 10 ns, (c) 2.1 times higher write efficiency (Δ/Ic) at 10 ns. Thanks to the above excellent MTJ stack design, it is the first time beyond 2X nm generation that the advanced 18 nm Quad-MTJ achieves at least 6×10^{11 endurance with 10 years retention. Consequently, the advanced Quad-MTJ technologies have broken out the dilemma issue of retention and endurance even under scaling of 2X nm.}