| Patent application number | Description | Published |
|---|
| 20090021868 | Perpendicular magnetic recording head with a laminated pole - A laminated write pole layer for a PMR write head is disclosed in which a plurality of “n” magnetic layers and “n−1” non-magnetic spacers are formed in an alternating fashion on a substrate. The non-magnetic spacers promote exchange decoupling or antiferromagnetic coupling between adjacent magnetic layers. Writability is improved when the trailing magnetic layer has a thickness greater than the thickness of other magnetic layers and preferably >25% of the total thickness of the magnetic layers. The thicknesses of the other magnetic layers may be equal or may become progressively smaller with increasing distance from the trailing magnetic layer. In another embodiment, the non-magnetic spacer between the trailing magnetic layer and the nearest magnetic layer is replaced by a magnetic spacer made of a soft magnetic material to promote magnetic coupling and effectively increase the thickness of the trailing magnetic layer. | 01-22-2009 |
| 20090034130 | Shield design for magnetic recording head - A magnetic shield in which all domain patterns and orientations are stable and which are consistently repeated each time said shield is exposed to an initialization field, is disclosed. This has been achieved by giving it a suitable shape which ensures that all closure domains can align themselves at a reduced angle relative to the initialization direction while still being roughly antiparallel to one another. Most, though not all, of these shapes are variations on trapezoids. | 02-05-2009 |
| 20090052092 | Perpendicular magnetic recording head laminated with AFM-FM phase change material - A PMR writer is disclosed that minimizes pole erasure during non-writing and maximize write field during writing through an AFM-FM phase change material that is in an AFM state during non-writing and switches to a FM state by heating during writing. The main pole layer including the write pole may be comprised of a laminated structure having a plurality of “n” ferromagnetic layers and “n-1” AFM-FM phase change material layers arranged in an alternating manner. The AFM-FM phase change material is preferably a FeRh or FeRhX alloy (X=Pt, Pd, or Ir) having a Rh content >35 atomic %. AFM-FM phase change material may also be used as a flux gate to prevent yoke flux from leaking into the write pole tip. Heating for the AFM to FM transition is provided by write coils and/or a coil located near the AFM-FM phase change material to enable faster transition times. | 02-26-2009 |
| 20090091861 | Perpendicular magnetic recording write head with a side shield - A side shield structure for a PMR write head is disclosed that narrows write width and minimizes adjacent track and far track erasure. The side shield structure on each side of the write pole has two sections. One section along the ABS and adjacent to the pole tip has a height (SSH | 04-09-2009 |
| 20090268344 | Graded bevel tapered write pole design for field enhancement - A structure and a process for a perpendicular write pole that provides increased magnetic flux at the ABS is disclosed. This is accomplished by increasing the amount of write flux that originates above the write gap, without changing the pole taper at the ABS. Three embodiment of the invention are discussed. | 10-29-2009 |
| 20100110585 | Perpendicular magnetic recording write head with a trailing shield - Insertion of a two part trailing shield between the write gap and the upper return pole of a magnetic write head reduces the sensitivity of the latter to increases in the current driving the field coils (beyond the required minimum). A key feature is careful control of the distance between the upper component of the write shield and the main pole. A process for manufacturing the structure is outlined. | 05-06-2010 |
| 20110013321 | Enhanced hard bias in thin film magnetoresistive sensors with perpendicular easy axis growth of hard bias and strong shield-hard bias coupling - A hard bias (HB) structure for longitudinally biasing a free layer in a MR sensor is disclosed that is based on HB easy axis growth perpendicular to an underlying seed layer which is formed above a substrate and along two sidewalls of the sensor. In one embodiment, a conformal soft magnetic layer that may be a top shield contacts the HB layer to provide direct exchange coupling that compensates HB surface charges. Optionally, a thin capping layer on the HB layer enables magneto-static shield-HB coupling. After HB initialization, HB regions along the sensor sidewalls have magnetizations that are perpendicular to the sidewalls as a result of surface charges near the seed layer. Sidewalls may be extended into the substrate (bottom shield) to give enhanced protection against side reading. The top surface of the seed layer may be amorphous or crystalline to promote HB easy axis perpendicular growth. | 01-20-2011 |
| 20110014390 | Enhanced hard bias in thin film magnetoresistive sensors with perpendicular easy axis growth of hard bias and strong shield-hard bias coupling - A hard bias (HB) structure for longitudinally biasing a free layer in a MR sensor is disclosed that is based on HB easy axis growth perpendicular to an underlying seed layer which is formed above a substrate and along two sidewalls of the sensor. In one embodiment, a conformal soft magnetic layer that may be a top shield contacts the HB layer to provide direct exchange coupling that compensates HB surface charges. Optionally, a thin capping layer on the HB layer enables magneto-static shield-HB coupling. After HB initialization, HB regions along the sensor sidewalls have magnetizations that are perpendicular to the sidewalls as a result of surface charges near the seed layer. Sidewalls may be extended into the substrate (bottom shield) to give enhanced protection against side reading. The top surface of the seed layer may be amorphous or crystalline to promote HB easy axis perpendicular growth. | 01-20-2011 |
