Optimization of Spin-Valve Structure NiFe/Cu/NiFe/IrMn for Planar Hall Effect Based Biochips

Author

Tu, Bui Dinh ; Cuong, Le Viet ; Hung, Tran Quang ; Giang, Do Thi Huong ; Danh, Tran Mau ; Duc, Nguyen Huu ; Kim, CheolGi

Author_Institution

Dept. of Nano Magn. Mater. & Devices, Vietnam Nat. Univ., Hanoi

Volume

45

Issue

6

fYear

2009

fDate

6/1/2009 12:00:00 AM

Firstpage

2378

Lastpage

2382

Abstract

This paper deals with the planar Hall effect (PHE) of Ta(5)/NiFe(t_F)/Cu(1.2)/NiFe(t_P)/IrMn(15)/Ta(5) (nm) spin-valve structures. Experimental investigations are performed for 50 mumtimes50 mum junctions with various thicknesses of free layer (t_F = 4, 8, 10, 12, 16, 26 nm) and pinned layer (t_P = 1, 2, 6, 8, 9, 12 nm). The results show that the thicker free layers, the higher PHE signal is observed. In addition, the thicker pinned layers lower PHE signal. The highest PHE sensitivity S of 196 muV/(kA/m) is obtained in the spin-valve configuration with t_F = 26 nm and t_P = 1 nm. The results are discussed in terms of the spin twist as well as to the coherent rotation of the magnetization in the individual ferromagnetic layers. This optimization is rather promising for the spintronic biochip developments.

Keywords

Hall effect; biosensors; copper; ferromagnetic materials; iridium alloys; iron alloys; magnetic multilayers; magnetic sensors; magnetisation; manganese alloys; nickel alloys; spin valves; tantalum; Ta-NiFe-Cu-NiFe-IrMn-Ta; biosensors; ferromagnetic layers; magnetization; optimization; pinned layer; planar Hall effect based biochips; size 1 nm; size 10 nm; size 12 nm; size 16 nm; size 2 nm; size 26 nm; size 4 nm; size 6 nm; size 8 nm; size 9 nm; spin-valve structure; Biosensors; Hall effect; magnetization reversal; magnetoresistance; magnetoresistive devices;

fLanguage

English

Journal_Title

Magnetics, IEEE Transactions on

Publisher

ieee

ISSN

0018-9464

Type

jour

DOI

10.1109/TMAG.2009.2018580

Filename

4957761