CHEE-WEE LIU2022-04-252022-04-25202100189383https://www.scopus.com/inward/record.uri?eid=2-s2.0-85115170288&doi=10.1109%2fTED.2021.3110833&partnerID=40&md5=e061e96e17126c20172a691d26d8c112https://scholars.lib.ntu.edu.tw/handle/123456789/606964A back-end-of-line compatible 400 °C thermally robust perpendicular spin-orbit torque magnetic tunnel junction (p-SOT-MTJ) memory cell with a tunnel magnetoresistance ratio of 130% is demonstrated. It features an energy-efficient spin-transfer-torque-assisted field-free spin-orbit torque (SOT) switching and a novel interface-enhanced synthetic antiferromagnet (SAF). The optimal SAF with a Ru (9 ?) spacer sandwiched by Co/Pt multilayers has a high SAF coupling field of 2.8 kOe. The parallel magnetic coupling between the CoFeB-based reference layer and the bottom Co/Pt multilayer is enhanced by a magnet-coupling face-centered cubic textured Co/Pt (5 ?) multilayer buffer. The thermally induced Pt-Fe interdiffusion is effectively reduced by the W (3 ?) trilayers of texture-decoupling diffusion multibarrier. The Ta β -W and TaN β -W composite SOT channels are thick enough to be the etching stop and sustain 400 °C annealing without transforming to α -W. Using the harmonic Hall voltage measurement, the Ta/W and TaN/W channels exhibit the large effective spin Hall angle of approximately -0.21 and -0.27, respectively. Scaling magnetic tunnel junction (MTJ) down to 30 nm size can reduce the switching time due to single-domain switching based on the micromagnetic simulation. The damping constant of 0.018 is obtained by the ferromagnetic resonance measurement. A bigger damping constant reduces the switching time as predicted by the calibrated simulation. ? 1963-2012 IEEE.Damping constantfield-free switchingmagnetic tunnel junction (MTJ)spin Hall anglespin-orbit torque (SOT)Antiferromagnetic materialsBinary alloysCobalt compoundsDampingEnergy efficiencyEtchingIron alloysMultilayersPlatinum alloysSemiconductor storageSpin orbit couplingSwitchingTantalum compoundsTexturesTunnel junctionsTunnelling magnetoresistanceFace-centered cubicFerromagnetic resonance measurementsMagnetic tunnel junctionMicromagnetic simulationsSpin transfer torqueSynthetic antiferromagnetsThermally inducedTunnel magnetoresistanceMagnetic devices[SDGs]SDG7journal article10.1109/TED.2021.31108332-s2.0-85115170288