Western Digital (fremont), Inc.

Western Digital Technologies, Inc.

Neil David Knutson

Yu Lo

Steven C Rudy

Zhigang Bai

Tao Pan

Yan Chen

Savas Gider

Donghong Li

Wentao Yan

David E Fowler

Luc Chung

El-Amine Salhi

Nurul Amin

A heat-assisted magnetic recording (HAMR) disk drive read/write head has the write head located adjacent the trailing surface of the gas-bearing slider with the read head located adjacent the write head, which is the reversed location from conventional read/write heads. This results in reduced write head protrusion during writing which allows for a reduced minimum fly-height for the slider. For a HAMR read/write head that uses a heater to protrude the read head closer to the disk during reading, the reversed location allows for better heater efficiency and thus reduced heater power.

Heat-assisted magnetic recording (HAMR) read/write head with reversed read head and write head

A method and system provide a magnetic read apparatus. The magnetic read apparatus includes a substrate and an isolation circuit. The isolation circuit includes a bias resistor and a capacitor residing on the substrate. The bias resistor and the capacitor are connected in parallel through the substrate.

Magnetic read apparatus having an improved read sensor isolation circuit

Systems and methods for using NFT disc test structures for controlling NFT disc length during manufacture of an HAMR writer are disclosed. An NFT is manufactured concurrently with one or more pairs of pin-disc and disc-less test structures. The NFT disc and pin dimensions may be substantially similar to the pin and disc dimensions of the pin-disc test structure. The disc length of the pin-disc test structure is measured as a function of the difference in resistance between the two test structures and other parameters. Capturing the disc length variation subsequently enables adjustment of the NFT electronic lapping guide stripe height to reduce length variation in the NFT pin.

Test structures for measuring near field transducer disc length

A method and system provide a magnetic transducer having an air-bearing surface (ABS). The magnetic transducer includes a main pole and at least one coil for energizing the main pole. The coil(s) have a number of turns. The magnetic transducer also includes at least one shunt coupled to at least one of the number of turns. At least one remaining turn of the number of turns carries a current. The shunt(s) carry a portion of the current from the shunted turn of the number of turns. Thus, the coil(s) have an effective number of turns is less than the number of turns.

Magnetic writer having a partially shunted coil

A magnetic recording device includes a slider having an air bearing surface (ABS), a leading side, and a trailing side and a head residing on the slider. The head has a first magnetic transducer and a first heater for heating an area proximal to the first magnetic transducer. A first shield (S1) comprising a first material is on the leading side of the first magnetic transducer and a second shield (S2) comprising the first material is on the trailing side of the first magnetic transducer. A first pole (P1) comprising the first material is on the trailing side of the second shield (S2), and the first pole (P1) is between 0.6 micron and 2.0 micron thick; and the second shield (S2) is less than 0.6 micron thick. A hard disk drive includes the magnetic recording device.

Magnetic recording head with dynamic fly height heating and having thermally controlled pole tip protrusion to control and protect reader element

A method and system provide a magnetic read and/or write transducer for use in disk drive. A read transducer has an air-bearing surface (ABS) and includes a read sensor, a nonmagnetic gap, a heater, and an expander. The nonmagnetic gap is adjacent to a portion of the read sensor and has a first coefficient of thermal expansion (CTE). The heater heats a portion of the magnetic read transducer. The expander is adjacent to a portion of the nonmagnetic gap and has a second CTE greater than the first CTE. The write transducer includes a pole, a coil, an insulator adjacent to and for insulating the coil, a heater and an expander. The expander has a CTE greater than the insulator's CTE.

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Fremont, CA, United States of America

Neil David Knutson