Increased Perpendicular TMR in FeCoB/MgO/FeCoB Magnetic Tunnel Junctions by Seedlayer Modifications

Author

Sokalski, Vincent ; Bromberg, David M. ; Moneck, Matthew T. ; En Yang ; Jian-Gang Zhu

Author_Institution

Dept. of Electr. & Comput. Eng., Carnegie Mellon Univ., Pittsburgh, PA, USA

Volume

49

Issue

7

fYear

2013

fDate

Jul-13

Firstpage

4383

Lastpage

4385

Abstract

By modifying the seedlayer in perpendicular FeCoB/MgO/FeCoB magnetic tunnel junctions (MTJs), we observe an increase in maximum tunneling magnetoresistance (TMR) from 65% up to 138%. It´s found that decreasing the Ta deposition rate in Ta/Ru/Ta underlayers allows for greater annealing temperatures (up to 350 ) while still maintaining a perpendicular easy axis. An improvement is also seen at a lower temperature where both seedlayers maintain a perpendicular FeCoB easy axis indicating that the increase in TMR is not solely related to annealing at a higher temperature.

Keywords

annealing; boron alloys; cobalt alloys; interface magnetism; iron alloys; magnesium compounds; tunnelling magnetoresistance; FeCoB-MgO-FeCoB; TMR; annealing; deposition; perpendicular easy axis; perpendicular magnetic tunnel junctions; perpendicular tunneling magnetoresistance; seedlayer modifications; Annealing; Circuit stability; Junctions; Magnetic tunneling; Silicon; Thermal stability; Tunneling magnetoresistance; FeCoB; MgO; p-MTJ; perpendicular anisotropy;

fLanguage

English

Journal_Title

Magnetics, IEEE Transactions on

Publisher

ieee

ISSN

0018-9464

Type

jour

DOI

10.1109/TMAG.2013.2242448

Filename

6559222