Abstract: The invention relates to bit patterned recording media having a stop layer for chemical mechanical polishing. One embodiment of the present invention is a method of manufacturing a magnetic recording medium comprising the step of planarizing by chemical mechanical polishing until the stop layer is reached. The present invention also provides a magnetic recording medium having a stop layer.

Abstract: A method is disclosed for defining discrete magnetic and non-magnetic regions on the magnetic film layer of a storage media substrate. The method applies anodic oxidation of a cobalt-containing magnetic film layer to remove cobalt, followed by controlled deposition of a non-magnetic matrix into the regions where the cobalt has been removed. Deposition may either be electrodeposition, collimated vacuum deposition, or other methods depending upon the composition of the non-magnetic matrix being deposited. The method may be performed in a single electrochemical cell.

Abstract: Provided is an electric field information reading head for reading information from a surface electric charge of an information storage medium, the electric field information reading head comprising a semiconductor substrate having a resistance region formed in a central part at one end of a surface facing a recording medium, the resistance region being lightly doped with impurities, and source and drain regions formed on both sides of the resistance region, the source region and the drain region being more highly doped with impurities than the resistance region. The source region and the drain region extend along the surface of the semiconductor substrate facing the recording medium, and electrodes are connected electrically with the source region and the drain region respectively. In addition, provided is a method of fabricating the electric field information reading head and a method of mass-producing the electric field information reading head on a wafer.

Abstract: An aspect of the disclosure relates to data storage heater systems with diodes. In one embodiment, data storage systems include a first electrical connection point, a second electrical connection point, a first electrical branch, and a second electrical branch. The first electrical branch is connected to the first and the second electrical connection points. The first electrical branch has first and second diodes biased in a first direction. The second electrical branch is connected to the first and second electrical connection points. The second electrical branch has third and fourth diodes biased in a second direction.

Abstract: A fluid dynamic bearing motor and method are described, wherein motor components, including complex shaped motor components, are molded of plastic. The molding ensures form control and dimensional control thereby accomplishing design requirements, and eliminating or reducing component costs and component machining. The mold can be shaped to form various motor geometries, thereby eliminating the need for multiple component assembly and related assembly costs. In an aspect, a plastic integral motor hub is formed by injection molding. Alternatively, a plastic motor hub is affixed to a metal sleeve. In another aspect, fluid containment structures are molded into the motor component, reducing the number of components as compared with machined metal components. In a further aspect, bearing structures such as grooves are molded into the motor component, thereby eliminating processes such as electrochemical machining. In yet a further aspect, a plastic hub faces a thrustplate, reducing expensive sleeve machining.

Abstract: A magnetic stack having a ferromagnetic free layer, a metal oxide layer that is antiferromagnetic at a first temperature and non-magnetic at a second temperature higher than the first temperature, a ferromagnetic pinned reference layer, and a non-magnetic spacer layer between the free layer and the reference layer. During a writing process, the metal oxide layer is non-magnetic. For magnetic memory cells, such as magnetic tunnel junction cells, the metal oxide layer provides reduced switching currents.

Abstract: An access control system and method are provided, which include a plurality of authorities, a plurality of access control elements and an access control list. Each authority associates at least one of a plurality of proof of knowledge operations with at least one of a plurality of proof of knowledge credentials. Each access control element identifies a Boolean combination of at least one of the authorities. The access control list identifies one or more of the access control elements by which a method to be executed can be authenticated.

Abstract: A near field transducer includes gold and at least one dopant. The dopant can include at least one of: Cu, Rh, Ru, Ag, Ta, Cr, Al, Zr, V, Pd, Ir, Co, W, Ti, Mg, Fe, or Mo. The dopant concentration may be in a range from 0.5% and 30%. The dopant can be a nanoparticle oxide of V, Zr, Mg, Ca, Al, Ti, Si, Ce, Y, Ta, W, or Th, or a nitride of Ta, Al, Ti, Si, In, Fe, Zr, Cu, W or B.

Abstract: Methods and devices are provided for microwave-assisted magnetic recording with collocated microwave and write fields. An illustrative device includes a magnetic write pole and one or more alternating-field components. The magnetic write pole is configured for providing a magnetic write field. The one or more alternating-field components are disposed to at least partially coincide with the magnetic write pole. The one or more alternating-field components are configured to provide an alternating magnetic field having a microwave frequency and an orientation that is at least partially transverse to the magnetic write field.

Abstract: A recessed field is formed surrounding resist columns that are in a pattern of bit patterned magnetic media. A filler layer is formed in the recessed field. The resist columns are removed to leave recesses in the filler layer that replicate the pattern. Bit patterned magnetic media is formed in the recesses.

Abstract: Spin-transfer torque memory includes a composite free magnetic element, a reference magnetic element having a magnetization orientation that is pinned in a reference direction, and an electrically insulating and non-magnetic tunneling barrier layer separating the composite free magnetic element from the magnetic reference element. The free magnetic element includes a hard magnetic layer exchanged coupled to a soft magnetic layer. The composite free magnetic element has a magnetization orientation that can change direction due to spin-torque transfer when a write current passes through the spin-transfer torque memory unit.

Abstract: Method and apparatus for writing data to a magnetic memory element, such as a spin-torque transfer random access memory (STRAM) memory cell. In accordance with various embodiments, a write current is applied through a magnetic memory element to initiate magnetic precession of the element to a desired magnetic state. A flow of a field assist current is subsequently initiated adjacent the magnetic memory element during continued application of the write current to induce a magnetic field upon the element. The field assist current persists after the write current is terminated to provide field assisted precession to the desired magnetic state.

Abstract: An apparatus that includes a first read shield and a second read shield and a reader stack between the first and second read shields. The first and second read shields each include a tilted magnetization layer closest to the reader stack to control magnetic field flux lines in a free layer of the reader stack and thereby improve a selectivity of the reader to independently sense and isolate media transitions.

Abstract: Method and apparatus for transferring data in a memory. A semiconductor memory includes a plurality of memory cells each having a resistive sense element (RSE) in series with a switching device. A conductive word line extends in a first direction adjacent the memory cells and is connected to a gate structure of each of the switching devices. A plurality of conductive bit lines extend in a second direction adjacent the memory cells, each bit line providing a connection node that interconnects a respective pair of the memory cells. A control circuit senses a programmed state of a selected memory cell by setting each of the bit lines on a first side of the selected memory cell to a first voltage level, setting each of the remaining bit lines on an opposing second side of the selected memory cell to a second voltage level, and setting the word line to a third voltage level.

Abstract: A shallow trench discrete track media structure is fabricated by etching a magnetic recording layer to provide a plurality of discrete magnetic data tracks separated by shallow trenches. Each shallow trench has a trench floor formed at a depth in the magnetic recording layer that is less than the thickness of the magnetic recording layer. Exposed regions of the magnetic recording layer beneath the trench floor are reacted with reactive plasma to diminish the magnetic moment of the exposed regions.

Abstract: An example memory cell may have at least a tunneling region disposed between a conducting region and a metal region, wherein the tunneling region can have at least an active interface regio disposed between a first tunneling barrier and a second tunneling barrier. A high resistive film is formed in the interface region with migration of ions from both the metal and conducting regions responsive to a write current to program the memory cell to a selected resistive state.

Abstract: A memory unit includes a giant magnetoresistance cell electrically coupled between a write bit line and a write source line. The giant magnetoresistance cell includes a free magnetic layer separated from a first pinned magnetic layer by a first non-magnetic electrically conducting layer. A magnetic tunnel junction data cell is electrically coupled between a read bit line and a read source line. The magnetic tunnel junction data cell includes the free magnetic layer separated from a second pinned magnetic layer by an oxide barrier layer. A write current passes through the giant magnetoresistance cell to switche the giant magnetoresistance cell between a high resistance state and a low resistance state. The magnetic tunnel junction data cell is configured to switch between a high resistance state and a low resistance state by magnetostatic coupling with the giant magnetoresistance cell, and be read by a read current passing though the magnetic tunnel junction data cell.

Abstract: A magnetic writer is formed with a texture on a surface of a write pole, preferably on a surface associated with the trailing edge of the writer. This texturing results in, in effect, a magnon-magnon scattering process that increases the surface damping of the pole and thus decreases the write field rise time. Rare earth elements can also be added in amounts sufficient to further increase the damping.

Abstract: Method and apparatus for handling data in a data storage device. In accordance with some embodiments, a memory space with a plurality of garbage collection units (GCUs) that are each arranged into pages of memory that store user data identified by logical addresses (LAs) and each GCU has a metadata region that stores metadata that correlates the LAs with physical addresses (PAs). A header region in each page of memory stores a bitmask and a sequence map of the LAs in each page that are used by a log manager to creates a bitmask table stored in a first cache and a hierarchical log stored in a second cache. The bitmask table and hierarchical log are used to determine when the LAs stored in the selected GCU are stale, and update the bitmask for each page in the selected GCU after the stale data has been erased.