Observation of boron diffusion in an annealed Ta/CoFeB/MgO magnetic tunnel junction with standing-wave hard x-ray photoemission.
- Resource Type
- Article
- Authors
- Greer, A. A.; Gray, A. X.; Kanai, S.; Kaiser, A. M.; Ueda, S.; Yamashita, Y.; Bordel, C.; Palsson, G.; Maejima, N.; Yang, S.-H.; Conti, G.; Kobayashi, K.; Ikeda, S.; Matsukura, F.; Ohno, H.; Schneider, C. M.; Kortright, J. B.; Hellman, F.; Fadley, C. S.
- Source
- Applied Physics Letters. 11/12/2012, Vol. 101 Issue 20, p202402. 4p. 3 Graphs.
- Subject
- *BORON spectra
*KIRKENDALL effect
*ANNEALING of metals
*MAGNETIZATION
*PHOTOELECTRON spectroscopy
*SPINTRONICS
*STANDING waves
- Language
- ISSN
- 0003-6951
The CoFeB/MgO system shows promise as a magnetic tunnel junction with perpendicular magnetization and low critical current densities for spin-torque driven magnetization switching. The distribution of B after annealing is believed to be critical to performance. We have studied the distribution of B in a Ta/Co0.2Fe0.6B0.2/MgO sample annealed at 300 °C for 1 h with standing-wave hard x-ray photoemission spectroscopy (SW-HXPS). Comparing experimental rocking curve data to x-ray optical calculations indicates diffusion of 19.5% of the B uniformly into the MgO and of 23.5% into a thin TaB interface layer. SW-HXPS is effective for probing depth distributions in such spintronic structures. [ABSTRACT FROM AUTHOR]