| Patent application number | Description | Published |
|---|
| 20080259506 | ESD, cross talk and noise pickup minimizing scheme for CPP and TMR devices - A slider mounted CPP GMR or TMR read head sensor is protected from electrostatic discharge (ESD) damage and from noise and cross-talk from an adjacent write head by means of a balanced resistive/capacitative shunt. The shunt includes highly resistive interconnections between upper and lower shields of the read head and a grounded slider substrate and a low resistance interconnection between the lower pole piece of the write head and the substrate. The capacitances between the pole piece and the upper shield, the upper shield and the lower shield and the lower shield and the substrate are made equal by either forming the shields and pole piece with equal surface areas and separating them with dielectrics of equal thicknesses, or by keeping the ratio of area to insulator thicknesses equal. | 10-23-2008 |
| 20080273277 | Composite shield structure of PMR writer for high track density - Improved writability and a substantial reduction in adjacent track erasure are achieved by incorporating a composite shield structure in a PMR writer. There is a trailing shield formed a certain distance above the top surface of a write pole, a leading shield formed a certain distance below the bottom surface of the write pole, and a partial side shield having a section formed on each side of the write pole. The partial side shield thickness is less than that of the write pole. Each partial side shield section has a side that is parallel to the nearest write pole side and a top surface that is offset from the write pole top surface by 0 to 0.15 microns. A plurality of magnetic connections between two or more shield elements is employed to ensure correct magnetic potential. The large write pole has a flare angle of 45 to 75 degrees. | 11-06-2008 |
| 20080278864 | Novel CPP device with an enhanced dR/R ratio - A CPP-GMR spin valve having a composite spacer layer comprised of at least one metal (M) layer and at least one semiconductor or semi-metal (S) layer is disclosed. The composite spacer may have a M/S, S/M, M/S/M, S/M/S, M/S/M/S/M, or a multilayer (M/S/M) | 11-13-2008 |
| 20080316644 | PMR with improved writability and process controllability by double layer patterning - Improved writability and a sharper neck transition are achieved in a PMR writer with a yoke that has essentially vertical sidewalls and a write pole that has sidewalls with a beveled angle. An alumina mold is made with a negative differential bevel angle by employing a two mask process. A first photoresist layer is patterned and etched to form a rectangular trench in an alumina layer. The trench extends beyond the intended ABS plane and in the opposite direction into the intended yoke area. A second photoresist layer is patterned into a yoke shape that is partially superimposed over the rectangular trench. After a second RIE process, the yoke opening adjoins the trench at a neck transition point along each long trench side. The volume of magnetic material in the yoke adjacent to the neck is thereby maximized. Dimension control of the main pole becomes independent of ABS positioning errors. | 12-25-2008 |
| 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 |
| 20090091862 | Method to make PMR head with integrated side shield (ISS) - A PMR head comprises a substrate, a magnetic pole formed over the substrate, the pole having a pole tip having a cross-sectional tapered shape wherein the pole tip is surrounded by a write gap layer, an integrated shield comprising side shields on the substrate laterally surrounding the pole tip and a trailing shield overlying the pole tip and integral with the side shields. | 04-09-2009 |
| 20090116145 | Perpendicular shield pole writer with tapered main pole and tapered non-magnetic top shaping layer - A PMR writer with a tapered main pole layer and tapered non-magnetic top-shaping layer is disclosed that minimizes trailing shield saturation. A second non-magnetic top shaping layer may be employed to reduce the effective TH size while the bulk of the trailing shield is thicker to allow a larger process window for back end processing. A sloped surface with one end at the ABS and a second end 0.05 to 0.3 microns from the ABS is formed at a 10 to 80 degree angle to the ABS and includes a sloped surface on the upper portion of the main pole layer and on the non-magnetic top shaping layer. An end is formed on the second non-magnetic top shaping layer at the second end of the sloped surface followed by forming a conformal write gap layer and then depositing the trailing shield on the write gap layer and along the ABS. | 05-07-2009 |
| 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 |
| 20090279213 | Stabilized shields for magnetic recording heads - A basic design is disclosed for bottom shield (S | 11-12-2009 |
| 20090323229 | Modified shield shape for perpendicular recording head to reduce sensitivity to external fields - In a read-write head, the shields can serve as magnetic flux conductors for external fields, so that they direct a certain amount of flux into the recording medium. This problem has been overcome by the addition to the shields of a pair of tabs located at the edges closest to the ABS. These tabs serve to prevent flux concentrating at the edges so that horizontal fields at these edges are significantly reduced. Said tabs need to have aspect ratios of at least 2 and may be either triangular or rectangular in shape. Alternatively, the tabs may be omitted and, instead, outer portions of the shield's lower edge may be shaped so as to slope upwards away from the ABS. | 12-31-2009 |
| 20100027162 | Method to reduce sensitivity of a perpendicular recording head to external fields - In a read-write head, the shields can serve as magnetic flux conductors for external fields, so that they direct a certain amount of flux into the recording medium. This problem has been overcome by the addition to the shields of a pair of tabs located at the edges closest to the ABS. These tabs serve to prevent flux concentrating at the edges so that horizontal fields at these edges are significantly reduced. Said tabs need to have aspect ratios of at least 2 and may be either triangular or rectangular in shape. Alternatively, the tabs may be omitted and, instead, outer portions of the shield's lower edge may be shaped so as to slope upwards away from the ABS. | 02-04-2010 |
| 20100085666 | Low noise magneto-resistive sensor utilizing magnetic noise cancellation - A magnetic sensor, formed from a pair of magnetically free layers located on opposing sides of a non-magnetic layer, and method for its manufacture, are described. Biasing these free layers to be roughly orthogonal to one another causes them to be magnetostatically coupled in a weak antiferromagnetic mode. This enables the low frequency noise spectra of the two free layers to cancel one another. Careful control of the SH/TW ratio is an important feature of the device | 04-08-2010 |
| 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 |
| 20100277832 | PMR writer device with multi-level tapered write pole - A perpendicular magnetic recording (PMR) head is fabricated with a multi-level tapered write pole. The write pole comprises a main pole with a tapered tip on which is formed at least one yoke that has a tapered edge. The edge of the yoke is recessed from the ABS of the tapered tip, giving the write pole a stepped profile. The tapered tip can be two sloped surfaces that are symmetric about a mid plane of the main pole or the taper can be a single sloped edge on the leading side or the trailing side of the pole. The yoke structure can consist of a single yoke formed on one side of the main pole or it can consist of two yokes formed symmetrically on both the leading and trailing sides of the main pole. Other yoke/pole combinations are also described as are various shield formations. The write pole structure creates an efficient channeling of magnetic flux to the ABS surface of the pole tip which produces magnetic recording field at high area densities. | 11-04-2010 |
| 20100315735 | Plasmon antenna with magnetic core for thermally assisted magnetic recording - A TAMR (Thermal Assisted Magnetic Recording) write head uses the energy of optical-laser generated plasmons in a plasmon antenna to locally heat a magnetic recording medium and reduce its coercivity and magnetic anisotropy. To enable the TAMR head to operate most effectively, the maximum gradient of the magnetic recording field should be concentrated in the small region being heated. Typically this does not occur because the spot being heated by the antenna is offset from the position at which the magnetic pole concentrates its magnetic field. The present invention incorporates a magnetic core within a plasmon antenna, so the antenna effectively becomes an extension of the magnetic pole and produces a magnetic field whose maximum gradient overlaps the region being heated by edge plasmons being generated in a conducting layer surrounding the antenna's magnetic core. | 12-16-2010 |
| 20100328816 | Composite shield structure of PMR writer for high track density - Improved writability and a substantial reduction in adjacent track erasure are achieved by incorporating a composite shield structure in a PMR writer. There is a trailing shield formed a certain distance above the top surface of a write pole, a leading shield formed a certain distance below the bottom surface of the write pole, and a partial side shield having a side shield section formed on each side of the write pole. The partial side shield thickness is less than that of the write pole. Each partial side shield section has a side that is parallel to the nearest write pole side and a top surface that is offset from the write pole top surface by 0 to 0.15 microns. A plurality of magnetic connections between two or more shield elements is employed to ensure correct magnetic potential. The large write pole has a flare angle of 45 to 75 degrees. | 12-30-2010 |
| 20110051285 | Method to reduce sensitivity of a magnetic read-write head to external magnetic fields - In a read-write head, the shields can serve as magnetic flux conductors for external fields, so that they direct a certain amount of flux into the recording medium. This problem has been overcome by the addition to the shields of a pair of tabs located at the edges closest to the ABS. These tabs serve to prevent flux concentrating at the edges so that horizontal fields at these edges are significantly reduced. Said tabs need to have aspect ratios of at least 2 and may be either triangular or rectangular in shape. Alternatively, the tabs may be omitted and, instead, outer portions of the shield's lower edge may be shaped so as to slope upwards away from the ABS. | 03-03-2011 |
| 20110051293 | Tapered PMR write pole with straight side wall portion - A main pole layer with a tapered trailing side is disclosed that has three sections each with a write pole portion along the ABS and a yoke portion. A lower section has a bottom surface including a leading edge at the write pole tip and sidewalls with a bevel angle between 4 and 20 degrees. The middle section has essentially vertical sidewalls with a tapered side starting at the trailing edge and extending to a back side of the write pole and into the yoke. An upper section includes a portion of the tapered side and a top surface of the main pole layer and has a sidewall with a bevel angle from 0 to 45 degrees. The thickness of the middle section is greater than the pole height variation caused by variations in back end processes including ion milling and lapping to reduce erase width (EW) variations. | 03-03-2011 |
| 20110058283 | Perpendicular recording device having reduced sensitivity to external fields - In a read-write head, the shields can serve as magnetic flux conductors for external fields, so that they direct a certain amount of flux into the recording medium. This problem has been overcome by the addition to the shields of a pair of tabs located at the edges closest to the ABS. These tabs serve to prevent flux concentrating at the edges so that horizontal fields at these edges are significantly reduced. Said tabs need to have aspect ratios of at least 2 and may be either triangular or rectangular in shape. Alternatively, the tabs may be omitted and, instead, outer portions of the shield's lower edge may be shaped so as to slope upwards away from the ABS. | 03-10-2011 |
| 20110063755 | PMR write with flux choking area - A PMR writer having a trailing shield structure is disclosed in which a flux choking layer (FCL) formed adjacent to the ABS provides a means to limit the amount of flux flowing from the trailing shield to a first write shield (WS | 03-17-2011 |
| 20110097601 | Wrap-around shielded writer with highly homogeneous shield material - A perpendicular magnetic recording (PMR) head is fabricated with a main pole shielded laterally by a pair of side shields, shielded above by a trailing shield and shielded optionally below by a leading shield. The shields and the seed layers on which they are formed are formed of materials having substantially the same physical characteristics including the same material composition, the same hardness, the same response to processes such as ion beam etching (IBE), chemical mechanical polishing (CMP), mechanical lapping, such as the slider ABS lapping, the same coefficient of thermal expansion (CTE) as well as the same B | 04-28-2011 |
| 20110097602 | External field robustness of read/write head shields - An improved magnetic shield for a perpendicular magnetic write head is disclosed. Its main feature is a pair of tabs at the shield's bottom corners. Said tabs are significantly wider at their point of attachment to the shield than further away from the shield. The end portions of each tab slope upwards (away from the ABS) at an angle of about ten degrees. A process for manufacturing the shield is also disclosed. | 04-28-2011 |
| 20110164334 | Integrated focusing elements for TAMR light delivery system - A device to facilitate Thermally Assisted Magnetic Recording (TAMR), and a method for its manufacture, are described. One or more cylindrical lenses are used to focus light from a laser diode onto a wave-guide and a nearby plasmon antenna. Five embodiments of the invention are described, each one featuring a different way to couple the laser light to the optical wave-guide. | 07-07-2011 |
