Demonstrating a tunneling magneto-resistive read head

Author

Song, Dian ; Nowak, Janusz ; Larson, Richard ; Kolbo, Paul ; Chellew, Robert

Author_Institution

Seagate Technol. Inc., Bloomington, MN, USA

Volume

36

Issue

5

fYear

2000

fDate

9/1/2000 12:00:00 AM

Firstpage

2545

Lastpage

2548

Abstract

We demonstrate the feasibility of a read head using a high-resistance spin-dependent tunneling (SDT) junction. The head consists of a 1.5 μm or 1.7 μm wide flux guide on top of the junction. The junction is about 0.8 μm wide and varies in height, There is a pinned layer at the bottom of the stack. The tunnel barrier is made by plasma oxidation of about 10 Å of aluminum. The barrier has resistance of about 3.7 kΩ μm², leading to a typical head resistance of a few kΩ. The heads are lapped to the edge of the junction, and show 5% to 8% TMR during transfer curve measurement. Isolated pulses during the spin stand test shows large signal up to 5.7 mV. We find a voltage sensing preamp is a better choice over a current sensing one

Keywords

giant magnetoresistance; magnetic flux; magnetic heads; magnetoresistive devices; oxidation; tunnelling; 0 to 5.7 mV; 0.8 micron; 1.5 micron; 1.7 micron; flux guide; head resistance; high-resistance spin-dependent tunneling junction; isolated pulses; pinned layer; plasma oxidation; spin stand test; transfer curve measurement; tunnel barrier; tunneling magneto-resistive read head; voltage sensing preamp; Electrodes; Insulation; Magnetic flux; Magnetic heads; Magnetic tunneling; Oxidation; Perpendicular magnetic recording; Plasmas; Spin valves; Testing;

fLanguage

English

Journal_Title

Magnetics, IEEE Transactions on

Publisher

ieee

ISSN

0018-9464

Type

jour

DOI

10.1109/20.908503

Filename

908503