[14p-PA1-1~74] 10 Spintronics and Magnetics

[14p-PA1-46] Estimation of switching energy barrier by String method assuming side-wall damage in perpendicular magnetized magnetic tunnel junctions

〇Hiroshi Naganuma^1,2,3, Hideo Sato^1,2,3, Shoji Ikeda^1,2,3, Tetsuo Endoh^1,2,3,4,5 (1.CIES Tohoku Univ., 2.CSIS Tohoku Univ., 3.CSRN Tohoku Univ., 4.Tohoku Univ., 5.RIEC Tohoku Univ.)

Keywords:MRAM, Micromagnetics simulation, Process damage

The influence of magnetic damage at the sidewall of a perpendicular MTJs, that are core device of STT-MRAM, was discussed based on thermal stability factor D, double-logarithm plot of normalized switching energy barrier E and saturation magnetization M_s, and their exponential slope n. D was calculated by string method and the domain wall was formed in all the simulation condition. Naively, n was increased with increasing the thickness of damaged layer of sidewall. It was found that the sidewall damage can be explained by reduction of M_s and exchange stiffness constant A_s rather than the interfacial perpendicular anisotropy.