International Business Machines Corporation

Icko E Tim Iben

Wayne Alan McKinley

Lee Curtis Randall

George G Zamora

Guillermo Francisco Paniagua

William Thomas Bandy, Iv

Darrell G Follett

Richard L Bradshaw

Sassan K Shahidi

In one embodiment, a system is provided for detecting a damaged magnetoresistive sensor. The system includes a processor, and logic or software stored in hardware that is executable by the processor. The logic or software is configured to, when executed by the processor, determine a scaled resistance of a plurality of sensors. The scaled resistances are measured against at least a first bias current, I, or against a square of the at least a first bias current I, I. The system also includes logic or software stored in hardware that is configured to, when executed by the processor, output a representation of the measurements.

System for detecting damaged magnetoresistive sensor

Methods and systems for detecting a damaged magnetoresistive sensor are disclosed. In one embodiment, resistances of a plurality of sensors are measured at at least a first bias current level. Further, it is determined whether one of the sensors has a resistance that is at least a predetermined amount higher or lower than the resistances of the other sensors. Moreover, output indicates that the one of the sensors has a resistance that is at least a predetermined amount higher than the resistances of the other sensors.

Methods and systems for utilizing sensor resistance for detecting damage to magnetoresistive sensors

A system and method for detecting a damaged magnetoresistive sensor includes measuring a median DiffPN value of a group of GMR sensors on a module, the sensors characterized as having been deposited on a same wafer and having been lapped as a single unit; comparing the DiffPN values to the median; determining that physical and/or magnetic damage has occurred to an individual sensor if the difference in the DiffPN value of the individual sensor from the median is greater than a statistically predetermined value for the group of sensors; where the difference is at least one times the average of the standard deviations of a large number of normal modules or the average of the standard deviations of a large number of modules, wherein at least the largest and the smallest DiffPN value within the module is not included in the calculation of the module's standard deviation.

Methods for detecting damage to magnetoresistive sensors

A cable in one embodiment comprises a plurality of leads; and an electrostatically dissipative adhesive operatively electrically coupling the leads together, the adhesive comprising a mixture of an adhesive material and electrically conductive particles intermixed with the adhesive material. A method in one embodiment comprises applying an electrostatically dissipative adhesive to exposed leads of a cable for operatively electrically coupling the leads together, the adhesive comprising a mixture of an adhesive material and electrically conductive particles intermixed with the adhesive material. Additional embodiments are presented.

Cable having ESD dissipative adhesive electrically connecting leads thereof

A cable having an electrostatic discharge (ESD) dissipative layer in one embodiment includes a plurality of leads; an ESD dissipative layer; and a coupling layer between the leads and the ESD dissipative layer, the coupling layer electrically connecting each of the leads, individually, to the ESD dissipative layer. A cable having an electrostatic discharge (ESD) dissipative layer in another embodiment comprises at least 16 leads; an ESD dissipative layer; and a coupling layer between the leads and the ESD dissipative layer, the coupling layer electrically connecting each of the leads, individually, to the ESD dissipative layer. A method for fabricating a cable in one embodiment comprises coupling an electrostatic discharge (ESD) dissipative layer to a plurality of leads using a coupling layer between the leads and the ESD dissipative layer, the coupling layer electrically connecting each of the leads, individually, to the ESD dissipative layer.

Cable having ESD dissipative layer electrically coupled to leads thereof

An electrostatically dissipative adhesive in one embodiment includes a mixture comprising: an adhesive material; and electrically conductive particles intermixed with the adhesive material, the electrically conductive particles being present in an amount between 0 and about 10% by weight of a total weight of the mixture. An electrostatically dissipative adhesive in another embodiment includes a mixture comprising: an adhesive material; and electrically conductive particles intermixed with the adhesive material, the electrically conductive particles being present in an amount between 0 and about 10% by weight of a total weight of the mixture, wherein the mixture has at least 50% of a lap shear strength as measured in accordance with ISO 4587 after curing for 72 hours at 22&#xb0; C. as the raw adhesive material has as measured in accordance with ISO 4587 after curing for 72 hours at 22&#xb0; C.

Electrostatic dissipative adhesive

A method in one embodiment includes applying a current to a lead of a tunneling magnetoresistance sensor for inducing joule heating of the lead or a heating layer, the level of joule heating being sufficient to anneal a magnetic layer of the sensor; and maintaining the current at the level for an amount of time sufficient to anneal the tunneling magnetoresistive (TMR) sensor. A system in one embodiment comprises a first lead coupled to one end of a tunneling magnetoresistance sensor stack; a second lead coupled to another end of the sensor stack; and a third lead coupled to the first lead, the third lead being selectively coupleable to a ground, wherein a current applied to the first lead at a predetermined level when the third lead is coupled to the ground induces joule heating of the first lead or a heating layer coupled to the first and third leads, the joule heating applied for a predetermined amount of time being sufficient to anneal a magnetic layer of the sensor. Additional systems and methods are also presented.

System having a TMR sensor with leads configured for providing joule heating

A method in one embodiment includes applying an organic coating to a magnetic head for reducing exposure of the head to oxidation promoting materials; and storing the magnetic head. A method in another embodiment includes applying an organic coating to a magnetic head for reducing exposure of the head to oxidation promoting materials, the organic coating being applied to the magnetic head after the head is installed in the magnetic storage system. Another method includes fabricating a tape having an applicator portion for applying an organic coating to a magnetic head for reducing exposure of the head to oxidation promoting materials; applying the organic coating to the applicator portion of the tape; and applying a lubricant to a data portion of the tape. A method in another embodiment includes fabricating a tape having a data portion, and a cleaning portion for removing an organic coating from a magnetic head.

Systems and methods for protecting a sensitive device from corrosion

A method for detecting a damaged magnetoresistive sensor in one embodiment includes measuring a resistance of a first sensor upon application thereto of a positive bias current; measuring the resistance of the first sensor upon application thereto of a negative bias current; determining a difference in the measured resistances at positive and negative currents of the first sensor; measuring a resistance of a second sensor upon application thereto of a positive bias current; measuring the resistance of the second sensor upon application thereto of a negative bias current; determining a difference in the measured resistances at positive and negative currents of the second sensor; and outputting at least one of the differences, or a derivative of the at least one of the differences. Additional methods are also presented.

A system in one embodiment includes a substrate; a thin film structure coupled to the substrate, the thin film structure comprising at least one of read transducers and write transducers; a closure; and an electrostatically dissipative adhesive coupling the closure to at least one of the thin film structure and the substrate. The adhesive comprises a mixture comprising: an adhesive material; and electrically conductive particles intermixed with the adhesive material, the electrically conductive particles being present in an amount between 0 and about 10% by weight of a total weight of the mixture. The closure defines at least a portion of a tape bearing surface. Additional systems and methods are also presented.

Systems having components coupled with electrostatic dissipative adhesive

In one embodiment, a method for detecting a damaged magnetoresistive sensor includes analyzing readback signals of a plurality of sensors each being positioned over data tracks on a passing magnetic medium; determining whether at least one of the readback signals is out of phase with respect to the other readback signals, and/or whether at least one of the readback signals has a significantly lower amplitude that the other readback signals. Additional methods are also presented.

A method for protecting a magnetic head according to one embodiment includes reducing a relative humidity in a vicinity of a magnetic head by passing an elevated bias current through a sensor of the head during at least some time periods when the sensor is not in use for reading data, the elevated bias current being chosen to be sufficient to heat the sensor to a level which will reduce the local relative humidity to below a threshold level for reducing or eliminating corrosion of the sensor. Additional methods are also presented.

Growing community of inventors

Santa Clara, CA, United States of America

Icko E Tim Iben