Improved magnetic tunnel junction with amorphous seed layer, surface treatment,and high-polarization magnetic materials

Author

Lee, J.E. ; Rho, Y. ; Oh, S.C. ; Kim, H.-J. ; Ha, Y.K. ; Bae, J.S. ; Baek, I.G. ; Park, S.O. ; Chung, U.I. ; Moon, J.T.

Author_Institution

Sch. of Inf. & Commun. Eng., Sungkyunkwan Univ., Suwon, South Korea

Volume

40

Issue

4

fYear

2004

fDate

7/1/2004 12:00:00 AM

Firstpage

2275

Lastpage

2277

Abstract

Dependence of magnetic tunnel junction (MTJ) properties on seed layer, surface treatment and magnetic materials was investigated to improve TMR ratio. Roughness of tunnel oxide layer generated from seed layer roughness reduces TMR ratio as well as RA product owing to locally reduced oxide layer thickness. Crystallinity of seed layer is found to be important to enhance TMR ratio. Surface treatment with ion beam etching on a pinned layer improves tunnel oxide uniformity providing higher TMR ratio. Also, highly polarized magnetic material increases TMR ratio but the effect of surface treatment is quite different depending on pinned layer material.

Keywords

amorphous magnetic materials; etching; focused ion beam technology; surface roughness; surface treatment; tunnelling magnetoresistance; RA product; TMR ratio; amorphous seed layer; high-polarization magnetic materials; highly polarized magnetic material; ion beam etching; magnetic polarization; magnetic tunnel junction; oxide layer thickness; pinned layer material; seed layer crystallinity; seed layer roughness; surface treatment; tunnel oxide layer; tunnel oxide uniformity; tunnelling magnetoresistance ratio; wettability; Amorphous materials; Crystallization; Etching; Ion beams; Magnetic materials; Magnetic properties; Magnetic tunneling; Rough surfaces; Surface roughness; Surface treatment; Amorphous seed; IBE; MTJ; TMR; ion beam etch; magnetic polarization; magnetic tunnel junction; ratio; roughness; surface treatment; tunnel oxide; tunnelling magnetoresistance; wettability;

fLanguage

English

Journal_Title

Magnetics, IEEE Transactions on

Publisher

ieee

ISSN

0018-9464

Type

jour

DOI

10.1109/TMAG.2004.828968

Filename

1325476