Abstract: A perpendicular write head having a wrap around trailing shield for reducing stray field writing and adjacent track interference. A method for constructing such a write head allows for excellent control of side shield gap thickness and trailing shield gap thickness, and allows the ratio of side gap to trailing gap thicknesses to be maintained at about two to one as desired. The method includes depositing forming a write pole by constructing a mask which may include a bi-layer hard mask, and then ion milling to form the write pole. Once the write pole has been formed, a layer of alumina or some other non-magnetic material can be conformally deposited. A reactive ion mill (RIM) can be performed to open up the top of the write pole (remove the horizontally disposed portions of the alumina layer). Then, a second layer of alumina or some other non-magnetic material can be deposited, and the write pole can be plated.

Abstract: A magnetic write head for perpendicular magnetic data recording having a notched write pole for reduced magnetic core width (MCW) dependence on skew. The write pole is configured with a notch that can extend to or slightly beyond the flare point of the write pole, and is formed on the leading portion of the write pole. The notch can have a notch depth, as measured from the ABS of 50-200 nm or about 120 nm. The notch can have a notch height, measured in the down track direction that is 40-90 nm or 20-90 percent of the write pole height.

Abstract: A magnetic write head having a write pole with a tapered trailing edge. The write head has a non-magnetic step layer and a non-magnetic bump formed on the front edge of the magnetic step layer. A non-magnetic trailing gap layer is formed over the tapered trailing edge of the write pole and over the non-magnetic bump and over the non-magnetic step layer. A magnetic trailing shield is formed over at least a portion of the non-magnetic gap layer.

Abstract: Methods for fabrication of tapered magnetic poles with a non-magnetic front bump layer. A magnetic pole may have a tapered surface at or near an air bearing surface (ABS), wherein a thickness of the write pole increases in a direction away from the ABS. A non-magnetic front bump layer may be formed on the tapered surface of the magnetic pole and away from the ABS. The front bump layer may increase the separation distance between a shield layer and the magnetic pole near the tapered surface, thereby improving the performance of the write head.

Abstract: A method for manufacturing a magnetic write head having a write pole and a trailing wrap around magnetic shield, and having a non-magnetic step layer and a non-magnetic bump to provide additional spacing between the write pole and the trailing wrap around shield at a location removed from the air bearing surface. A magnetic write pole material is deposited on a substrate and a non-magnetic step layer is deposited over the write pole. A reactive ion milling can he used to pattern the non-magnetic step layer to have a front edge that is located a desired distance from an air hearing surface. A patterning and ion milling process is then performed to define a write pole, and then a layer of alumina is deposited and ion milled to from a tapered, non-magnetic bump at the front the non-magnetic step layer.

Abstract: A magnetic structure for use in a magnetic head for avoiding stray field writing. The magnetic structure can be for example a magnetic shield or could be a magnetic pole of a write head and is particularly advantageous for use in a perpendicular recording system, because such perpendicular recording systems are especially susceptible to stray field writing. The magnetic structure includes a forward protruding portion that extends toward the air bearing surface (ABS) of the head also includes first and second wing portions that extend laterally from the forward protruding portion. The wing portions each have includes an inner constant recess portion, and an outer tapered portion. The inner constant recess portion of each wing prevents stray field writing while also preventing magnetic saturation, the outer tapered portions, which taper away from the ABS as they extend laterally outward, further prevent stray field writing by removing the outer corners of the shield away from the ABS.

Abstract: Methods are provided for fabricating a write head with a self aligned wrap around shield and a self aligned flared region of a write pole. A flare point and a track width of a write pole may be fabricated using multiple processes. The multiple processes utilize several masking structures to define the track width and the flare point of the write pole. A mask structure is formed to cover a first portion of the write pole. An edge of the mask structure adjacent to an exposed second portion of the write pole defines a flare point of the write pole. Various structures of the write head, including shield gap layers, a wrap around shield and a flared region (e.g., the yoke) of the write pole may be fabricated from the flare point defined by the mask structure.

Abstract: A perpendicular magnetic write head having a conformal wrap around trailing shield. The write head includes a write pole that can be configured with a trapezoidal shape as viewed from the Air Bearing Surface (ABS) and which includes a wrap around trailing magnetic shield. The magnetic shield has a trailing portion that is separated from the leading edge of the write pole by a non-magnetic trailing gap, and has side shield portions that are separated from first and second side portions of the write pole by first and second non-magnetic side gaps. The magnetic shield can be configured with notches at either side of the trailing portion of magnetic shield. These notches can extend in the trailing direction by a distance that is preferably ¼ to 1 times the trailing gap thickness. The width of the straight, trailing portion of the shield is preferable ½ to 1 times of the main pole width.

Abstract: A method of fabricating a single-pole perpendicular magnetic recording head to contain a bevel angle promotion layer that facilitates the fabrication of the bevel angle in a trapezoidal main pole. The bevel angle promotion layer is made of a non-magnetic material that is softer than the material (e.g., Al2O3) that normally underlies the main pole. In one embodiment, the bevel angle promotion layer is formed between an end of the yoke and the air bearing surface (ABS), with the top surface of the bevel angle promotion layer being substantially coplanar with the top surface of the yoke. In other embodiment the bevel angle promotion layer is integrated with a leading edge taper material, which is formed of a magnetic material, to broaden the magnetic flux path between the yoke and the main pole.

Abstract: Write elements are discussed having a write pole and an associated trailing shield. A leading side of the trailing shield faces a trailing side of the write pole. The leading side of the trailing shield has a shape such that a center portion of the leading side has less of a separation from the trailing side of the write pole than track edge portions of the leading side of the trailing shield. An exemplary shape the leading side of the trailing shield may be a convex shape when viewed from the ABS. The shape of the leading side of the trailing shield causes the trailing shield to shunt less of the magnetic field from the trailing side of the write pole at the track edges so that the written transition at the track edge will not lag behind the written transition at the track center allowing for a straighter transition.

Abstract: In a perpendicular recording head, a notch is formed in the top write gap at a location on top of the main pole. A perpendicular head with this notched top write gap structure has less transition curvature and better writability while reducing the adjacent track interference (ATI). Also, the process used to fabricate the head ensures that the trailing edge (writing edge) of the main pole is extremely flat with no corner rounding.

Abstract: A perpendicular magnetic recording system has a write head with a main perpendicular write pole connected to a yoke with first and second electrical coils. The first coil is wrapped around the yoke on one side of the main pole, and the second coil is wrapped around the yoke on the other side of the main pole. The first end of each coil is connected to a respective terminal. The second ends of the two coils are connected together and connected to a common terminal. A lead-time circuit is connected between the common terminal and the first end of one of the coils. Immediately after the direction of write current is switched by the write driver, the lead-time circuit causes the current in one of the coils to lead the current in the other coil. The current displacement between the two coils creates a precession of the magnetic flux reversal, thereby reducing the switching time of the write head.

Abstract: A perpendicular magnetic recording write head has a main pole and return poles that are substantially coplanar. The write head includes a main pole, two return poles and a connecting stud that are all formed as a single layer in a single deposition and patterning step. The coplanar main and return poles lie in a plane parallel to the cross-track direction. The two return poles are thus spaced from the main pole in the cross-track direction. The main pole includes a write pole connected to it but lying in a plane spaced in the along-the-track direction from the plane of the main pole. The write head includes a helical coil wrapped around the main pole. The magnetic flux path is from the write pole to the disk recording layer in a data track aligned with the write pole, to the disk underlayer beneath the recording layer, through the underlayer to data tracks spaced cross-track from the data track aligned with the write pole, and back through the return poles.

Abstract: A magnetic structure for use in a magnetic head for avoiding stray field writing. The magnetic structure can be for example a magnetic shield or could be a magnetic pole of a write head and is particularly advantageous for use in a perpendicular recording system, because such perpendicular recording systems are especially susceptible to stray field writing. The magnetic structure includes a forward protruding portion that extends toward the air bearing surface (ABS) of the head also includes first and second wing portions that extend laterally from the forward protruding portion. The wing portions each have a front edge that is recessed from the ABS. The wings are tapered so that the amount of recess of the front edge of the wings increases with lateral distance from the center of the magnetic structure.

Abstract: Methods for improving within wafer and wafer to wafer yields during fabrication of notched trailing shield structures are disclosed. Ta/Rh CMP stop layers are deposited prior to planarization and notch formation to ensure a planar surface for trailing shield structures. These stop layers may be blanket deposited or patterned prior to CMP. Patterned stop layers produce the highest yields.

Abstract: A method for determining a magnetic anisotropy of a free layer of a magnetoresistive sensor. The method includes forming a functional magnetoresistive sensor and also a test sensor on a wafer. The test sensor has a sensor stack that is identical to that of the functional sensor, however the test head does not have a magnetic bias structure for biasing the free layer. A series of tests can be performed to construct a transfer curve for the test sensor. This can then be used to determine a magnetic anisotropy of the test head, which also corresponds to a magnetic anisotropy of the functional head.

Abstract: A method for manufacturing a write pole for a perpendicular magnetic write head. The method employs a damascene process to construct the write pole with a very accurately controlled track width. The method includes depositing a layer of material that can be readily removed by reactive ion etching. This material can be referred to as a RIEable material. A mask is formed over the RIEable material and a reactive ion etching is performed to form a tapered trench in the RIEAble material. A CMP stop layer can the be deposited, and a write pole plated into the trench. A CMP can then be performed to define the trailing edge of the write pole. Another masking, etching and plating step can be performed to form a trailing, wrap-around magnetic shield.

Abstract: A perpendicular write head includes a main pole comprising high moment magnetic layers laminated with both soft magnetic layers and non-magnetic layers for antiferromagnetic coupling (AFC) between the high moment material layers. The perpendicular write head includes a return pole connected to the main pole by a back gap closure at a distal end and separated from the main pole by a gap at an air bearing surface (ABS). A write coil is positioned between the main pole and the return pole and the surface area of the return pole at the ABS is substantially larger than the surface area of the main pole at the ABS.

Abstract: A double notched magnetic structure for use in a magnetic head for avoiding stray field writing. The structure could be a magnetic shield, magnetic pole of a write head or some other magnetic structure used in a magnetic head of a magnetic recording system, and has notches formed at both the front end (adjacent to the ABS) and at the back end (away from the ABS). The notches at the front end form a forward protruding portions that performs the necessary function of the structure, such as magnetic shielding, and has laterally extending recessed portions (recessed by the front notches) that move the flux focal points of the structure away from the ABS to avoid stray field writing. The back notches form a backward extending portion that affects the geometry of the structure to prevent the focusing of magnetic flux caused by stray magnetic fields having a component perpendicular to the ABS.

Abstract: A magnetic head structure for use in perpendicular magnetic recording. The magnetic head includes a magnetic write head having a return pole with a magnetic shunt structure extending from the back end opposite the ABS. The magnetic shunt structure prevents magnetic field from the write coil from reaching and affecting the read head. More specifically the shunt structure prevents magnetic field from the portion of the write coil beyond the back gap (as measured from the ABS) from magnetizing a magnetic shield of the read head. The shunt structure is also configured so as to avoid stray field writing. The size and shape of the shunt structure is therefore, limited to avoid attracting stray fields that might cause such stray field writing.