International Business Machines Corporation

Hitachi Global Storage Technologies Netherlands B.v.

Peter John Melz

Jih-Shiuan Luo

Ciaran Avram Fox

Chin-Yu Yeh

Lydia Baril

Joseph Francis Smyth

Clayton V Wilbur

Angel G Arellano

A system, method and computer program product provide an annealing process for setting a magnetization condition of a read head. An amount of heat for stabilizing magnetization condition of a read head is calculated. A width and amplitude of a voltage pulse that generates the calculated amount of heat in the read head are calculated. A voltage pulse of the calculated width and amplitude is applied to the read head for generating Joule heating in the read head. The width of the voltage pulse is less than one second.

System and method for pre-stressing a read head for improving performance thereof

An automated production process for the screening of the read-width (RW) and/or the stripe-height (SH) for every magnetoresistive (MR) read sensor element in a wafer substrate. The method of this invention uses the RW and/or SH values found with optical examination by electron microscopy of several of the MR sensor elements to estimate two substrate coefficients that relates the optical RW and SH measurements to heating-delta measurements, &dgr;&equals;(RH&minus;RC)/RC, where RH is the sensor resistance when hot and RC is the sensor resistance when cold, both of which can be measured using automated equipment. These relationships are sufficiently similar among all MR sensor elements manufactured on a single wafer substrate during a single manufacturing procedure that, when the hot resistance RH is measured at a constant applied voltage, the heating-delta, may be used with a first substrate coefficient to estimate the read-width RW of each MR sensor element for quality-control purposes during manufacture. When the hot resistance RH is measured at a constant applied current, the heating-delta may be used with a second substrate coefficient to estimate the stripe-height SH of each MR sensor element for quality-control purposes during manufacture.

Method for the rapid measurement of magnetoresistive read head dimensions

A matrix addressed electrochromic display includes first and second spaced apart opposed planar panels, a dielectric spacer peripherally sealing the panels to provide an interior cavity therebetween to define a display region, an electrochromic fluid filling the interior cavity, a plurality of parallel rows and columns of electrodes disposed in the mating surfaces of the first and second panels respectively and a low output impedance electrical refresh circuit coupled to electrically energize the electrodes in a repetitive matrix selection pattern to provide a selected dot matrix display.

Matrix addressed electrochromic display

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Hollister, CA, United States of America

Peter John Melz