Abstract: A hard disk drive is disclosed including a voice coil motor and a magnetic sensor communicating with a control circuit. A magnetic sensor reading is created and used to stop access operations in response to the reading of an external magnetic field that may be strong enough to disrupt a slider accessing a rotating disk surface. Also disclosed are a main flex circuit and head stack assembly including the magnetic sensor for use in a hard disk drive. Control circuits and processors are disclosed for receiving the magnetic reading to stop access operations in hard disk drives. The hard disk drive may be a Perpendicular Magnetic Recording (PMR) hard disk drive.

Abstract: Provided is a thin film magnetic head capable of appropriately control the flow of magnetic flux from a yoke layer to a pole layer so as to prevent information from being overwritten without intention during recording. A perpendicular recording system thin film magnetic head is formed so that a portion of a yoke layer and a portion of a pole layer are connected to each other in a connecting surface. When a large amount of the magnetic flux contained in the yoke layer flows into the pole layer through the connecting surface, the large amount of the magnetic flux is concentrated in the connecting surface, so an excessive amount of the magnetic flux is not supplied to a front end portion of the pole layer, and an appropriate amount of the magnetic flux is supplied.

Abstract: A method for manufacturing a magnetic write head for perpendicular magnetic data recording. The method allows an upper write coil to be formed directly on a conformally deposited layer of non-magnetic material such as alumina which has been deposited over a magnetic shaping layer and write pole. The method allows the write coil to be constructed without the need for the deposition of a thick alumina fill layer and subsequent chemical mechanical polishing. This, therefore, avoids the necessity of such a chemical mechanical polishing step.

Abstract: A perpendicular magnetic recording media is provided having an imbalanced magnetic moment multilayer cap. The perpendicular magnetic recording media comprises a granular layer, and a multilayer cap structure exchange coupled to the granular layer. The multilayer cap structure includes upper and lower magnetic layers separated by a non-magnetic layer, where the upper magnetic layer has a magnetic moment greater than the lower magnetic layer. When an external field is applied to the recording media, a larger moment torque is triggered at the surface, and more efficient switching is facilitated. The upper magnetic layer may have a higher magnetic moment than the lower magnetic layer if the upper magnetic layer comprises a larger magnetic moment material than the lower magnetic layer. The upper magnetic layer may also have a higher magnetic moment than the lower magnetic layer if the upper magnetic layer has a greater thickness than the lower magnetic layer.

Abstract: Embodiments of the present invention help to provide a perpendicular magnetic recording head capable of writing a signal in a track having a small width. According to one embodiment, a perpendicular magnetic recording head includes an auxiliary pole, a main pole, a yoke, a coil, a first soft magnetic film and a second soft magnetic film. The yoke is in contact with the main pole. The coil is wound around a magnetic circuit composed of the auxiliary and main poles and the yoke. The first soft magnetic film is provided on both sides of the main pole with a non-magnetic film provided between the first soft magnetic film and the main pole. The second soft magnetic film is provided on the trailing side of the main pole with the non-magnetic film provided between the second soft magnetic film and the main pole. The first and second soft magnetic films are two types of plated magnetic films. One type of the plated magnetic films have respective thicknesses of 0.

Abstract: A top surface of a pole layer of a magnetic head includes: a first portion having a first edge located in a medium facing surface and a second edge opposite thereto; and a second portion located farther from the medium facing surface than the first portion and connected to the first portion at the second edge. The distance from a substrate to an arbitrary point on the first portion increases with increasing distance from the medium facing surface to the arbitrary point. The angle of inclination of the first portion taken at the arbitrary point with respect to a direction perpendicular to the medium facing surface increases stepwise or continuously with increasing distance from the medium facing surface to the arbitrary point. The angle of inclination taken at the first edge is greater than zero degree. The second portion extends in a direction substantially perpendicular to the medium facing surface.

Abstract: A magnetic head includes a medium facing surface, a coil, and a pole layer that generates a write magnetic field. The pole layer includes: a track width defining portion having a first end located in the medium facing surface and a second end opposite to the first end; and a wide portion connected to the second end. The first end defines the track width. The track width defining portion has a width taken in the track width direction, and the wide portion has a width taken in the track width direction that is greater than the width of the track width defining portion taken in the track width direction. The coil is helically wound only around the track width defining portion of the pole layer, and has a portion located between the medium facing surface and the wide portion.

Abstract: Provided are a perpendicular magnetic recording (PMR) head and a method of manufacturing the same. The PMR head includes a main pole, a return yoke, and a coil to which current is supplied so that the main pole generates a magnetic field required for recording data in a recording medium. The PMR head further includes side shields disposed on both sides of the main pole to be spaced a first gap apart from the main pole; and a top shield disposed opposite the main pole and the side shields to be spaced a second gap apart from the main pole and the side shields at one end of the return yoke.

Abstract: An encasing section that accommodates a pole layer includes an encasing layer having an encasing groove, and a nonmagnetic film disposed in the encasing groove at a position between the encasing layer and the pole layer. The pole layer includes a track width defining portion and a wide portion. The distance from a medium facing surface to the boundary between the track width defining portion and the wide portion is within a range of 10 to 300 nm. The track width defining portion has a first side surface and a second side surface, while the wide portion has a third side surface contiguous to the first side surface, and a fourth side surface contiguous to the second side surface. The encasing layer has a first wall surface and a second wall surface that form the encasing groove.

Abstract: A disk for a hard disk drive. The disk includes a first magnetic layer and a second magnetic layer. An intermediate layer consisting of cobalt and titanium is located between the first and second intermediate layers. The intermediate layer creates a finer grain size and larger crystalline anisotropy in the second magnetic layer, characteristics that are desirable when used with a perpendicular recording head.

Abstract: A magnetic head comprises a pole layer and first and second coils located in regions sandwiching the pole layer. Each of the two coils is flat-whorl-shaped. The first coil incorporates an inner connecting portion and an outer connecting portion opposite to the inner connecting portion. The second coil also incorporates an inner connecting portion and an outer connecting portion opposite to the inner connecting portion. The inner connecting portion of the first coil is electrically connected to the inner connecting portion of the second coil. The outer connecting portion of the first coil is electrically connected to the outer connecting portion of the second coil, too. In such a manner the two coils are electrically connected to each other in parallel.

Abstract: A perpendicular magnetic recording head includes a main magnetic pole layer and an auxiliary yoke layer that overlaps the main magnetic pole layer as viewed in a top view and is magnetically coupled to the main magnetic pole layer. The main magnetic pole layer includes a pole straight part exposed to an opposing surface opposite a recording medium, and a flared part that extends from the pole straight part in a height direction, the flared part broadening in a track width direction as the flared part extends in the height direction. The auxiliary yoke layer includes a flared part that extends from the recording medium-opposing surface, the flared part broadening in the track width direction as the flared part extends in the height direction. The flared part of the auxiliary yoke layer is disposed at a position located closer to the rear side in the height direction than the flared part of the main magnetic pole layer.

Abstract: A magnetic head has a main magnetic pole made of at least a magnetic material and a coil. The main magnetic pole has a stop layer through an inorganic insulating layer on both sides of the main magnetic pole in the widthwise direction. The boundary between the main magnetic pole and the metal layer becomes clear by the intervention of the inorganic insulating layer when viewing the flattened pattern plane by a scanning electron microscope and measuring the width of the main magnetic pole as a core width. The measurement accuracy of the main magnetic pole width can be improved and reductions in manufacturing yield rates which occur due to measurement errors can be prevented.

Abstract: In the perpendicular magnetic recording head according to the invention, the inclined surface, which is inclined toward the trailing side at the tilt angle ?1 with respect to the virtual vertical line extending from the top surface of the recording medium, is formed in the trailing-side cross section of the main magnetic pole in such a manner that it extends from the front-end surface in a direction where it is spaced apart from the recording medium. If the inclined surface is formed in the main magnetic pole as described above, the absolute value of the magnetic field gradient ?1 of the recording magnetic field can be increased and a magnetization inversion width can be decreased. It is thus possible to reduce magnetization inversion noise.

Abstract: There is provided a perpendicular recording magnetic head that is able to improve further the magnetic characteristic in writing the magnetic data by magnetizing a magnetic recording medium in the perpendicular direction rather than the prior art. In a perpendicular recording magnetic head, a recording magnetic field output surface of a main pole, which emits a recording magnetic field generated by an exciting coil toward a magnetic recording medium in the perpendicular direction, has a trapezoid shape in which a base on a leading side is longer than a base on a trailing side and has a distribution of a saturation magnetic flux density which is reduced from the trailing side to the leading side, whereby this structure contributes an improvement of the recording density.

Abstract: A method for constructing a magnetic write head using an electrical lapping guide to carefully control critical dimensions dining a lapping operation used to define an air bearing surface. The lapping guide is photolithographically patterned in a common photolithographic step with another write head structure so that special relation between the lapping guide and critical dimensions of the write head structure can be carefully maintained. For example, the electrical lapping guide can be patterned in a common photolithographic step as the write pole so that the location of the flare point can he carefully controlled with respect to the location of the lapping guide. A stitched flare structure can also be built together with the electrical lapping guide, then a self-aligned shield can be further built over this stitched flare structure so that both flare point and shield throat can be controlled tightly together by this electrical lapping guide during lapping process.

Abstract: Embodiments of the present invention help to provide an excellent perpendicular recording medium of high medium signal-to-noise (S/N) and with suppressed blurring in writing. According to one embodiment, a perpendicular recording layer is provided by way of a negative magnetic strain soft-magnetic underlayer above a substrate applied with texturing in the circumferential direction. The soft-magnetic underlayer has a first soft magnetic layer, a second soft magnetic layer and a nonmagnetic magnetic layer formed between the first soft magnetic layer and the second soft magnetic layer in which the first soft magnetic layer and the second soft magnetic layer are antiferromagnetically coupled to each other and the easy magnetization axis is directed in the radial direction.

Abstract: A crystallized ferromagnetic layer containing Fe, Co and/or Ni, formed as a polycrystalline ferromagnetic layer is used as a part of the anti parallel soft under layer (APS-SUL) structure in perpendicular media to reduce the thickness of the intermediate layer. The soft under layer structure consists of a non-magnetic spacer layer, whose thickness is adjusted to form an effective anti-parallel coupling between the two ferromagnetic layers. The magnetic coupling is formed in anti-parallel directions between a lower layer made up of an amorphous ferromagnetic layer and an upper layer made up of an amorphous ferromagnetic layer and the polycrystalline ferromagnetic layer. The effective magnetization of the soft under layers at remanence is zero. The preferred thickness of the polycrystalline ferromagnetic layer is 1 nm to 20 nm. An intermediate layer, such as Ru, is formed directly on the magnetic polycrystalline soft under layer and has a thickness of about 10 nm to 20 nm.

Abstract: A servo pattern is positioned in a DC erased portion to which a DC erase process has been performed, and recording tracks and track groove portions (discrete portions) are positioned in an AC erased portion to which an AC erase process has been performed. The track groove portions extend in a circumferential direction. The AC erased portion and the DC erased portion are both made of a magnetic material. In the servo pattern, four lines of preamble portions extending almost in a radial direction are formed and a plurality of pit portions disposed in a dotted manner in two lines are arranged. The pit portions are positioned rearward of the preamble portions in respect of a scanning direction of a magnetic head.