International Business Machines Corporation

Other

Hitachi Global Storage Technologies Netherlands B.v.

John Edward Eric Baglin

Bruce David Terris

Andrew John Kellock

Liesl Folks

Bruce Alvin Gurney

Dieter Klaus Weller

Timothy C Reiley

Linden James Crawforth

Richard Dale Bunch

Eric Wayne Flint

Koichi R Wago

Mark Whitney Hart

Modified strain regions are created in correlation to strain reactive structures that are subjected to a predetermined dimensional precision adjustment. The modified strain regions are created by impacting incident particles into exposed regions of the strain reactive structures. The irradiation by the incident particles creates a predetermined material disruption and consequently a change in strain energy. The strain energy, and the associated dimensional adjustment is dependent on the irradiation process and the sum properties of the modified strain regions and the strain reactive structure.

Particle irradiation method for modification of local strain in strain reactive structures

A magnetoresistive (MR) sensor can be shaped using ion beam irradiation and/or implantation through a mask introduced between a MR structure and an ion source. The mask covers selected portions of the MR structure to define the track width of the sensor. Ion irradiation and/or implantation reduces the magnetoresistance of the unmasked portions while leaving the masked portion substantially unaltered. The mask can be a photoresist mask, an electron beam resist mask, or a stencil mask. Alternatively the mask may be part of a projection ion beam system. Track width resolution is determined at the mask production step. The edges of the sensor can be defined by a highly collimated ion beam producing an extremely straight transition edge, which reduces sensor noise and improves sensor track width control. Improved hard bias layers that directly abut the sensor may be used to achieve a suitable stability. A variety of longitudinal bias schemes are compatible with ion beam patterning.

Ion beam definition of magnetoresistive field sensors

At least one modified strain region having a damage depth between 0.1 and 2 microns in a disk drive slider is created by implantation with ions, electrons or neutral atoms. The modified strain region induces a deformation of the disk drive slider. The nature and extent of this deformation is determined by the interaction between the slider and the modified strain region.

Modified strain region of strain reactive slider with implanted ions, electrons or neutral atoms

A method for making a patterned magnetic recording disk uses patterned ion implantation of the disk substrate. Energetic ions, such as He, N or Ar ions, are directed to the disk substrate through a mask, preferably a non-contact mask. They are implanted into the substrate, and the process causes localized topographic distortions in the substrate surface. A magnetic layer is then deposited over the substrate in the conventional manner, such as by sputtering. The result is a disk with patterned magnetic regions that are raised above the substrate surface. Because these regions are elevated, they are closer to the recording head in the disk drive and can thus be individually recorded to form discrete magnetic bits. Depending on the type of substrate used, the ion implantation can cause either localized swelling to form pillars or localized compaction to form pits. The patches of magnetic material on the tops of the pillars, or on the substrate surface between the pits, form the discrete magnetic bits.

Patterned magnetic recording disk with substrate patterned by ion implantation

A patterned magnetic recording disk, i.e., a disk with discrete magnetically recordable regions that can function as discrete magnetic bits, is formed by ion irradiating a continuous magnetic film of a chemically-ordered alloy having a tetragonal crystalline structure through a patterned non-contact mask. The ions cause disordering in the film and produce regions in the film that have no magnetocrystalline anisotropy. The regions of the film not impacted by the ions retain their chemical ordering and magnetocrystalline anisotropy and thus serve as the discrete magnetic regions that can be recorded as individual magnetic bits. The chemically-ordered alloy is preferably Co (or Fe) and Pt (or Pd) with the c-axis of the tetragonal crystalline film oriented at an angle less than 45 degrees relative to the plane of the film, so that after patterning the discrete magnetic regions can be recorded by horizontal magnetic recording.

Patterned magnetic recording media containing chemically-ordered FePt of CoPt

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Morgan Hill, CA, United States of America

John Edward Eric Baglin