Title :
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
fDate :
6/1/2009 12:00:00 AM
Abstract :
This paper deals with the planar Hall effect (PHE) of Ta(5)/NiFe(tF)/Cu(1.2)/NiFe(tP)/IrMn(15)/Ta(5) (nm) spin-valve structures. Experimental investigations are performed for 50 mumtimes50 mum junctions with various thicknesses of free layer (tF = 4, 8, 10, 12, 16, 26 nm) and pinned layer (tP = 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 tF = 26 nm and tP = 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;
Journal_Title :
Magnetics, IEEE Transactions on
DOI :
10.1109/TMAG.2009.2018580
