Method and apparatus for testing magnetic head with TMR element

Details Method and apparatus for testing magnetic head with TMR element Method and apparatus for testing magnetic head with TMR element

2007-11-20

2010-02-23

Whittington, Kenneth J (Department: 2858)

Electricity: measuring and testing

Magnetic

Magnetic information storage element testing

Reexamination Certificate

active

07667456

ABSTRACT:
A magnetic head testing apparatus having the function of evaluating pin holes in a tunnel barrier layer of a TMR element by a non destructive inspection is disclosed. The testing apparatus comprises a temperature control unit which sets a circumferential temperature of a TMR element, a bias electric current control unit which applies an electric current for measuring a resistance value, an element resistance measuring unit and a CPU which calculates a temperature coefficient. The CPU determines a pin hole state in the tunnel barrier layer based on the temperature coefficient.

REFERENCES:
patent: 5440233 (1995-08-01), Hodgson et al.
patent: 5729410 (1998-03-01), Fontana, Jr. et al.
patent: 5898547 (1999-04-01), Fontana, Jr. et al.
patent: 6195219 (2001-02-01), Smith
patent: 6440671 (2002-08-01), Mirzabekov et al.
patent: 6638442 (2003-10-01), Nakanishi et al.
patent: 6820020 (2004-11-01), Yokoyama et al.
patent: 6841395 (2005-01-01), Linn et al.
patent: 6898040 (2005-05-01), Jang et al.
patent: 6958928 (2005-10-01), Ooishi
patent: 6-118126 (1994-04-01), None
patent: 10-241333 (1998-09-01), None
patent: 2962234 (1999-08-01), None
patent: 2001-084540 (2001-03-01), None
patent: 2002-237012 (2002-08-01), None
Akerman et al. Tunneling Criteria for Magnetic-Insulator-Magnetic Structures, Nov. 5, 2001, Applied Physics Letters, vol. 79, No. 19, pp. 3104-3106.
Oliver et al., Tunneling Criteria and Breakdown for Low Resistive Magnetic Tunnel Junctions, Aug. 1, 2003, Journal of Applied Physics, vol. 93, No. 3, pp. 1783-1786.
Rudiger et al., “Temperature Dependent Resistance of Magnetic Tunnel Junctions as a Quality Proof of the Barrier”, Journal of Applied Physics, Jun. 1, 2001, vol. 89, No. 11, pp. 7573-7575.
Kikuchi et al, “Low-Resistance Ferromagnetic Tunnel Junction”, Fujitsu Science Tech. Journal 37,2, Dec. 2001, pp. 183-191.
Journal of Applied Physics, vol. 91, No. 7, “Dielectric Breakdown in Magnetic Tunnel Junctions Having An Ultrathin Barrier,” Bryan Oliver, Qing He, Xuefei Tang, and J. Novak, Apr. 1, 2002, pp. 4348-4352.
9thJoint MMM-Intermag Conference, Pinhole Evaluation of TMR Head by Temperature Coefficient of Resistance (TCR) Measurement, H. Naka et al., (2001), 5 pgs.
Ishikava, Makoto, “Squid Test Structures”, Sep. 2002.
Japanese Office Action dated Jun. 24, 2008 fro Appln. No. 2003-398157.

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