Western Digital (fremont), Inc.

Western Digital Technologies, Inc.

Changhe Shang

Daniele Mauri

Yun-Fei Li

Steven C Rudy

Kuok San Ho

Ming Mao

Xiaoyong Liu

Ji Li

Matthew R Gibbons

Yukimasa Okada

Carlos Corona

Curtis V Macchioni

Shaoping Li

Gerardo Bertero

Qunwen Leng

Yong Shen

Ge Yi

Lien-Chang Wang

Anup Roy

Shihai He

Yining Hu

Yingbo Zhang

Guolun Hao

Aspects of the present disclosure generally relate to magnetic recording heads of magnetic recording devices. A magnetic read head includes a first pinning layer magnetically oriented in a first direction, and a second pinning layer formed above the first pinning layer and magnetically oriented in a second direction that is opposite of the first direction. The magnetic read head includes a rear hard bias disposed outwardly of one or more of the first pinning layer relative or the second pinning layer. The rear hard bias is magnetically oriented to generate a magnetic field in a bias direction. The bias direction points in the same direction as the first direction or the second direction. The magnetic read head does not include an antiferromagnetic (AFM) layer between a lower shield and an upper shield.

Magnetic read sensors and related methods having a rear hard bias and no AFM layer

A slider includes a transducer including a magnetic structure having a front edge and a back edge. The slider further includes an electronic lapping guide (ELG) substantially coplanar with the magnetic structure and having a top edge and a bottom edge. The slider further includes a plurality of pads configured to calibrate a sheet resistance of the ELG and an offset of the ELG.

Electronic lapping guide in a magnetic recording transducer

A method and system provide a magnetic transducer having an air-bearing surface (ABS) and at least two read sensors. The magnetic transducer also includes a first read shield, a first read sensor, a middle shield, a second read sensor, a second read shield, a first electric gap and a second electric gap. The first read sensor is in a down track direction from the first read shield. The middle shield is in a down track direction from the first read sensor. The middle shield is between the first read sensor and the second read sensor. A first portion of the first electric gap is in a direction opposite to the down track direction from the first read sensor. The first read sensor and the second read sensor are between the first electric gap and the second electric gap in a cross-track direction.

Electric gaps and method for making electric gaps for multiple sensor arrays

A method and system for testing a read transducer are described. The read transducer includes a read sensor fabricated on a wafer. A system includes a test structure that resides on the wafer. The test structure includes a test device and a heater. The test device corresponds to the read sensor. The heater is in proximity to the test device and is configured to heat the test device substantially without heating the read sensor. Thus, the test structure allows for on-wafer testing of the test device at a plurality of temperatures above an ambient temperature.

Method and system for performing on-wafer testing of heads

A magnetic read transducer is described with a magnetoresistive sensor that has a free layer, and an antiferromagnetically-coupled (AFC) soft bias layer for magnetically biasing the free layer. The free layer has a first edge in a track width direction along an air-bearing surface (ABS). At least a portion of the AFC soft bias layer is conformal to at least a portion of a second edge of the free layer, and situated to form a magnetic moment at an angle with respect to a center line of the free layer. The center line of the free layer extends in the same direction as the free layer first edge that is in the track width direction along the ABS.

Antiferromagnetically-coupled soft bias magnetoresistive read head, and fabrication method therefore

A method for providing an electronic lapping guide (ELG) for a structure in a magnetic transducer are described. The structure has a front edge and a back edge. The ELG includes a stripe having a top edge and a bottom edge. The method includes calibrating a sheet resistance of the stripe and calibrating an offset of the top edge of the stripe from the back edge of the structure. The method further includes terminating the lapping based at least on the sheet resistance and offset of the ELG.

Method for providing and utilizing an electronic lapping guide in a magnetic recording transducer

A method of testing Pstiffness of a magnetoresistance (MR) sensor stack including a Ppinned layer is provided. The method comprises the step of applying an external magnetic field to the MR sensor stack. The external magnetic field is oriented substantially perpendicular to a magnetic field of the Ppinned layer. The method further comprises varying an amplitude of the external magnetic field, measuring a change in a resistance of the MR sensor stack in response to the varying amplitude of the external magnetic field, and calculating the Pstiffness based on the measured change in resistance.

Method and system for testing P2 stiffness of a magnetoresistance transducer at the wafer level

A method to fabricate a tunneling magnetoresistive (TMR) read transducer is disclosed. An insulative layer is deposited on a wafer substrate, and a bottom lead is deposited over the insulative layer. A laminated TMR layer, having a plurality of laminates, is deposited over the bottom lead. A TMR sensor having a stripe height is defined in the TMR layer, and a parallel resistor and first and second shunt resistors are also defined in the TMR layer. A top lead is deposited over the TMR sensor. The parallel resistor is electrically connected to the bottom lead and to the top lead. The first shunt resistor is electrically connected to the bottom lead and the wafer substrate, and the second shunt resistor is electrically connected to the top lead and the wafer substrate.

Method to fabricate an ESD resistant tunneling magnetoresistive read transducer

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Fremont, CA, United States of America

Changhe Shang