Dynamic magnetic information storage or retrieval – Head – Magnetoresistive reproducing head
Reexamination Certificate
2008-01-08
2008-01-08
Castro, Angel (Department: 2627)
Dynamic magnetic information storage or retrieval
Head
Magnetoresistive reproducing head
C029S603090, C428S811000
Reexamination Certificate
active
11704358
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.
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Castro Angel
Kabushiki Kaisha Toshiba
Magee Christopher R.
Pillsbury Winthrop Shaw & Pittman LLP
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