Enhanced annealing stability and perpendicular magnetic anisotropy in perpendicular magnetic tunnel junctions using W layer

Abstract : The magnetic properties of the perpendicular storage electrode (buffer/MgO/FeCoB/Cap) were studied as a function of annealing temperature by replacing Ta with W and W/Ta cap layers with variable thicknesses. W in the cap boosts up the annealing stability and increases the effective perpendicular anisotropy by 30% compared to the Ta cap. Correspondingly, an increase in the FeCoB critical thickness characterizing the transition from perpendicular to in-plane anisotropy was observed. Thicker W layer in the W(t)/Ta 1 nm cap layer makes the storage electrode highly robust against annealing up to 570 °C. The stiffening of the overall stack resulting from the W insertion due to its very high melting temperature seems to be the key mechanism behind the extremely high thermal robustness. The Gilbert damping constant of FeCoB with the W/Ta cap was found to be lower when compared with the Ta cap and stable with annealing. The evolution of the magnetic properties of bottom pinned perpendicular magnetic tunnel junctions (p-MTJ) stack with the W2/Ta1 nm cap layer shows back-end-of-line compatibility with increasing tunnel magnetoresistance up to the annealing temperature of 425 °C. The pMTJ thermal budget is limited by the synthetic antiferromagnetic hard layer which is stable up to 425 °C annealing temperature while the storage layer is stable up to 455 °C.
Type de document :
Article dans une revue
Applied Physics Letters, American Institute of Physics, 2017, 110 (20), pp.202401. 〈http://aip.scitation.org/doi/abs/10.1063/1.4983159〉. 〈10.1063/1.4983159〉
Liste complète des métadonnées

https://hal.archives-ouvertes.fr/hal-01629546
Contributeur : Antoine Chavent <>
Soumis le : mardi 26 juin 2018 - 18:05:11
Dernière modification le : mardi 26 juin 2018 - 18:37:20

Fichier

Chatterjee_Enhanced_2017.pdf
Fichiers éditeurs autorisés sur une archive ouverte

Identifiants

Collections

Citation

Jyotirmoy Chatterjee, Ricardo C. Sousa, Nicolas Perrissin, Stéphane Auffret, Clarisse Ducruet, et al.. Enhanced annealing stability and perpendicular magnetic anisotropy in perpendicular magnetic tunnel junctions using W layer. Applied Physics Letters, American Institute of Physics, 2017, 110 (20), pp.202401. 〈http://aip.scitation.org/doi/abs/10.1063/1.4983159〉. 〈10.1063/1.4983159〉. 〈hal-01629546〉

Partager

Métriques

Consultations de la notice

213

Téléchargements de fichiers

16