Evolution of barrier-resistance noise in CoFeB/MgO/CoFeB tunnel junctions during annealing

被引：37

作者：

Stearrett, Ryan ^{[1
]}

Wang, W. G. ^{[1
]}

Shah, L. R. ^{[1
]}

Gokce, Aisha ^{[1
]}

Xiao, J. Q. ^{[1
]}

Nowak, E. R. ^{[1
]}

机构：

[1] Univ Delaware, Dept Phys & Astron, Newark, DE 19716 USA

来源：

JOURNAL OF APPLIED PHYSICS | 2010年 / 107卷 / 06期

关键词：

1; f noise; annealing; boron alloys; cobalt alloys; iron alloys; magnesium compounds; magnetoresistive devices; sputtered coatings; tunnelling magnetoresistance; vacancies (crystal); 1/F NOISE; ROOM-TEMPERATURE; MAGNETORESISTANCE; DEPENDENCE;

D O I：

10.1063/1.3327440

中图分类号：

O59 [应用物理学];

学科分类号：

摘要：

The low-frequency resistance noise in sputtered-deposited magnetic tunnel junctions with MgO barriers has been measured as a function of annealing time at different annealing temperatures. The noise has a 1/f spectrum and it is quantified by a Hooge-like parameter alpha given in units of mu m(2). Unannealed devices have the highest noise levels and their alpha parameters exhibit a pronounced dependence on the voltage bias across the junction. A significant increase in tunneling magnetoresistance (TMR) is observed for short annealing times (on the order of minutes) at high temperatures and it is correlated with a large reduction in noise and in its bias dependence. The maximum TMR and minimum noise levels are reached at a later time that depends on temperature, being shorter at higher annealing temperatures. Devices annealed at 380 and at 430 degrees C exhibit the same minimum noise levels, alpha approximate to 2x10(-10) mu m(2). The origin of the resistance noise, its annealing time evolution, and its bias dependence are discussed and they are attributed to vacancy defects in the MgO barriers.

引用

页数：7

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