Title :
Challenging issues for terra-bit-level perpendicular STT-MRAM
Author :
Park, J.G. ; Shim, T.H. ; Chae, K.S. ; Lee, D.Y. ; Takemura, Y. ; Lee, S.E. ; Jeon, M.S. ; Baek, J.U. ; Park, S.O. ; Hong, J.P.
Author_Institution :
Dept. of Electron. Eng., Hanyang Univ., Seoul, South Korea
Abstract :
The current challenging issues for terra-bit-level perpendicular STT-MRAM cells have been reviewed in the view of four critical parameters such as TMR ratio, Δ, Jex, and α. The TMR ratio of p-MTJ spin-valves are reaching to <; 150% at the BEOL of >350°C. A single MgO based p- MTJ spin-valve could not satisfy Δ of > 74, proposing a double MgO based p-MTJ spin-valve. Jex in SyAF layer adequately met > 0.7erg/cm2 at BEOL of > 350°C. A Co2Fe6B2 based p-MTJ spin-valve limits to a of 0.005, necessary to develop a low α material such as full Heusler half-metal. Thus, an essential challenge in the future is to satisfy four critical parameters simultaneously at > 350°C and 300-mm TiN electrode wafers.
Keywords :
MRAM devices; boron alloys; cobalt alloys; electrodes; iron alloys; magnesium compounds; spin valves; titanium compounds; tunnelling magnetoresistance; Co2Fe6B2; Heusler half metal; MgO; TMR ratio; TiN; TiN electrode wafers; low α material; magnetic tunnel junction; p-MTJ spin valves; perpendicular STT-MRAM cells; size 300 nm; spin transfer torque; terra bit level; tunneling magnetoresistance; Annealing; Electrodes; Iron; Thermal stability; Tin; Tunneling magnetoresistance;
Conference_Titel :
Electron Devices Meeting (IEDM), 2014 IEEE International
DOI :
10.1109/IEDM.2014.7047081
