Wd Media, LLC

Western Digital Technologies, Inc.

Mrugesh Desai

Kumar Srinivasan

Harold H Gee

Mark A Nichols

Tuqiang Li

Prakash Mani

Cristian Papusoi

B Ramamurthy Acharya

Kyongha Kang

Sylvia Helena Florez

Emad Girgis

Ramamurthy Acharya

Jian Zhou

Eric Roddick

A method and system provide a magnetic recording media usable in a magnetic storage device. The magnetic recording media includes a substrate, at least one intermediate layer and a magnetic recording stack for storing magnetic data. The intermediate layer(s) include a majority phase having a first diffusion constant and a secondary phase having a second diffusion constant greater than the first diffusion constant. The magnetic recording stack residing on the intermediate layer such that the at least one intermediate layer is between the substrate and the magnetic recording stack.

Magnetic media having improved magnetic grain size distribution and intergranular segregation

Perpendicular magnetic recording media including a carbon grain isolation initiation layer for reducing intergranular exchange coupling in the recording layer are provided. In one such case, the media includes a substrate, a plurality of underlayers on the substrate, a grain isolation initiation layer (GIIL) on the plurality of underlayers, the GIIL including C, a metal, and an oxide, and a magnetic recording layer directly on the GIIL and including a non-ordered structure. In another case, a method of fabricating such magnetic media is provided.

Perpendicular recording media with carbon grain isolation initiation layer

A recording medium having improved signal-to-noise ratio (SNR) capabilities includes a NiFeX-based magnetic seed layer over a soft magnetic underlayer, where X comprises an element that is soluble in and has a higher melting point than Ni. X may be selected from a group of elements, including ruthenium (Ru), which may facilitate growth of smaller grains and distributions in the corresponding magnetic recording layer(s).

NiFeX-based seed layer for magnetic recording media

The present disclosure generally relates to a PMR media for use in a HDD. The PMR media has an amorphous ferri-magnetic material layer disposed within the capping structure. The amorphous ferri-magnetic material layer reduces the noise. The amorphous ferri-magnetic material layer may be disposed between capping layer or on top of the capping layers. Additionally, the amorphous ferri-magnetic material layer may contain Tb.

TbFeCo in PMR media for SNR improvement

A magnetic recording (PMR) disk structure is described. The PMR disk structure may include a magnetic capping layer being substantially free of an oxide, an upper magnetic layer with an oxide content disposed directly below and in contact with the magnetic capping layer, and an upper exchange coupling layer disposed below the upper magnetic layer.

Recording media with multiple exchange coupled magnetic layers

Methods for measuring media performance associated with adjacent track interference are provided. One such method includes iteratively writing data to a target track for each of a plurality of n frequencies, measuring a first signal amplitude and a first noise for each of the n sectors on the target track, writing an aggressor track pattern proximate the target track, measuring a second signal amplitude and a second noise for each of the n sectors on the target track, calculating a weighted sum for each of the signal amplitude measurements for each of the plurality of n frequencies, and calculating a weighted sum for each of the noise measurements for each of the plurality of n frequencies, and repeating the writing the aggressor track pattern, the measuring the second signal amplitude and the second noise, and calculating the weighted sums for preselected numbers of times.

Methods for measuring media performance associated with adjacent track interference

Cross-track density capability is predicted for a large number of writes based on a plurality of erase band width measurements. Over the plurality of erase band width measurements, a number of writes in a series of writes performed as part of an aggressing track sequence is varied. A model of the magnetic track width (MTW) as function of the number of writes employed in the MTW measurements may be generated and an estimate of the erase band width for a large number of writes derived from the model as a prediction of cross-track density capability.

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San Jose, CA, United States of America

Mrugesh Desai