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: A magnetic write head for perpendicular magnetic recording that has write pole, a return pole and a trailing shield that is magnetically connected with magnetic return pole. The write head includes a magnetic pedestal and first and second magnetic studs that connect the trailing shield with the pedestal. The studs are laterally spaced a distance that is not greater than 5 um from the nearest side of the write pole. In other words, the studs are spaced from each other a distance that is no greater than the width of the leading edge of the write pole plus 10 um. This spacing of the studs prevents saturation of the trailing shield, maximizing field gradient and ensuring optimal magnetic write performance.

Abstract: A magnetic write head having a magnetic cross yoke arranged to provide a cross magnetic field in a pole tip region of the magnetic head. The cross field, which is perpendicular to the magnetization of write pole, reduces the switching time of the write field, thereby increasing the speed with which the write head can record data. The write head can be a longitudinal write head or a perpendicular write head. In the case of a perpendicular write, the write head can include a write pole arranged to provide a magnetic write field that emits a magnetic field substantially perpendicular with an Air Bearing Surface (ABS). A magnetic cross yoke is formed having ends that are disposed at opposite sides of the pole tip region of the write pole. A magnetic cross field that extends across the pole tip region of the write pole slightly alters the direction of the magnetization of the write pole.

Abstract: A magnetic write head structure that maximizes write field strength while minimizing stray fields. The write pole structure maximizes write field strength by minimizing saturation of the magnetic pole tips, and minimizes stray field writing by preventing magnetic fields from extending laterally from the sides of the magnetic pole. The write head structure includes a write pole having a pole tip configured with a stair notched shape and a steep shouldered base beneath the stair notched portion. This configuration maximizes the amount of flux that can be delivered to the pole tip while also avoiding stray fields. The magnetic pole can also be configured with wing shaped extensions that extend laterally from the pole tip region but which are recessed from the ABS by a desired amount.

Abstract: A disk drive thin-film write head has a first ferromagnetic pole tip that includes a pedestal pole layer and a capping layer on the pedestal pole layer. A substantial portion of the pedestal pole layer is formed of a lower-moment alloy and the capping layer is formed of a higher-moment alloy and is made thick enough to compensate for the lower-moment alloy in the pedestal pole layer. The pedestal pole layer may be a bilayer of two different NiFe alloys with the upper layer in the bilayer having a higher moment, and the capping layer may be a CoFe alloy. The width of the pedestal pole layer is substantially reduced to reduce the pole tip area exposed. The reduced pole tip area and the increased use of lower-moment alloys enable a thinner protective film to be used to protect the pole tips from corrosion.

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.

Abstract: A hard disk drive (HDD) detects and measures external stray magnetic fields with existing HDD components. After detecting a strong external magnetic field, read and write operations of the HDD are suspended, and/or other proper corrective actions are taken to minimize loss of data. To measure the stray magnetic field, the magnetic head reader is used as a field sensor. The resistance of the reader changes in the presence of the field, such as with the preamp in the HDD. The resistance also changes with temperature. If the temperature inside the HDD is measured, the resistance change due to temperature is normalized. Even without being able to measure the HDD temperature, the stray magnetic field can be measured with a top head and a bottom head in the HDD. The temperature sensitivity of the reader is thereby cancelled out.

Abstract: A magnetoresistive read/write head having a first layer of alumina and a second layer of silicon dioxide overlaying a P3 layer of the head. In a preferred embodiment, the silicon dioxide layer is recessed away from an Air Bearing Surface (ABS) to reduce protrusion of a P2 layer and the P3 layer in the head, and to reduce degradation in the magnetic properties of the pole tips of the P2 and P3 layer ends.

Abstract: Magnetic heads having write coil structures with reduced electrical resistances for reducing thermal protrusion are disclosed. In one illustrative example, a magnetic head includes a magnetic yoke; a write gap layer formed between upper and lower poles of the magnetic yoke; and a write coil having a plurality of coil layers. Each coil layer of the write coil extends continuously between the upper and the lower poles through a plane defined by the write gap layer. Preferably, the write coil is formed using a damascene process, such that each coil layer is wider than each coil separating layer. Such a structure provides for a relatively large amount of coil materials to be used, which reduces the coil's electrical resistance. This, in turn, reduces the heat generated by the write coils during operation.

Abstract: A method and apparatus for optimizing data record quality on a disk for a pair of read and write heads, in which the write head is bigger, by adaptively varying linear and track density of overlapping recorded tracks to achieve a target storage capacity. In the method, target storage capacity and radial writing direction are selected. Read and write widths of heads are determined. A linear density and offset distance pairing for optimizing record quality at target storage capacity is determined, wherein offset distance is less than write width but greater than read width. The write head writes a track at the linear density, is offset in the radial direction by the offset distance, and the offset distance is stored. The write head writes a new track at the linear density. Offsetting, storing offset, and writing a new track are repeated until desired data is written into a cluster.

Abstract: A magnetic head for reading information from and writing information to a hard magnetic disk having reduced thermal protrusion at the air bearing surface. In some embodiments, a read-head portion of the magnetic head includes one or more read insulation layers, and a write-head portion of the magnetic head includes one or more write insulation layers. The magnetic head may optionally further include one or more insulation layers between the read-head portion and the write-head portion. One or more of these insulation layers includes a material with a negative thermal expansion characteristic, including but not limited to, carbon fiber, zirconium tungstate (Zr W2 O8), or hafnium tungstate (Hf W2 O8).

Abstract: A magnetic head having improved overwrite capabilities and reduced fringing fields are described along with methods of making the same. The magnetic head has a first pole piece and a second pole piece. The first pole piece includes a first bottom pole piece layer, a pedestal portion formed over the first bottom pole piece layer, and a notched top pole portion formed over the pedestal portion. A gap layer separates the second pole piece from the notched top pole portion. The pedestal portion has a first saturation magnetization MS1 and the top pole portion has a second saturation magnetization MS2 that is greater than the first saturation magnetization MS1. The top pole portion has a substantially planar top surface over which a portion of the gap layer and the second pole piece are formed.

Abstract: A method for fabricating a magnetic head using a modified P1 cap process. A first pole is formed. A cap is formed above the first pole. A gap layer is formed above the cap. A second pole is formed above the gap layer. Exposed portions of the gap layer are removed. The cap and first pole are milled for creating a shoulder of the first pole tapered upwardly towards the cap. Another method for fabricating a magnetic head includes forming a first pole, forming a gap layer above the first pole, forming a second pole above the gap layer, forming a layer of photoresist above the second pole, patterning the photoresist such that the photoresist covers areas of the gap layer positioned towards the second pole, removing exposed portions of the gap layer, removing part of exposed portions of the first pole for forming steps in the first pole on opposite sides of the photoresist, removing the photoresist, and milling for creating a shoulder of the first pole tapering upwardly towards the cap.

Abstract: Magnetic heads having write coil structures with reduced electrical resistances for reducing thermal protrusion are disclosed. In one illustrative example, a magnetic head includes a magnetic yoke; a write gap layer formed between upper and lower poles of the magnetic yoke; and a write coil having a plurality of coil layers. Each coil layer of the write coil extends continuously between the upper and the lower poles through a plane defined by the write gap layer. Preferably, the write coil is formed using a damascene process, such that each coil layer is wider than each coil separating layer. Such a structure provides for a relatively large amount of coil materials to be used, which reduces the coil's electrical resistance. This, in turn, reduces the heat generated by the write coils during operation.

Abstract: The magnetic head is formed with a narrow pole tip, and a pole tip heating element is fabricated to reduce the pole tip stress and increase its permeability, such that the magnetization switching speed of the pole tip is increased. The heating element is preferably electrically interconnected within the induction coil circuit of the magnetic head, such that the electrical current flowing through the induction coil also flows through the heating element. In a preferred embodiment, the heating element is fabricated above the second magnetic pole. The heating element is preferably formed with a resistance of approximately 0.2 to 1.0 ohms, such that the approximately 40 mA current that flows through the induction coil and the heating element creates a heating energy of the heating element of approximately 0.3 to 1.6 mW. The heating element can be comprised of a variety of materials such as Cu, W, NiFe, NiCr and IrRh.

Abstract: A method and apparatus for providing a pole tip structure having a shape for preventing over saturation of the pole tip structure is disclosed. A cap layer having a tail structure for reducing the saturation of the cap layer is formed over the pole structure. The tail structure includes an angled surface that can vary between approximately 15° and 65°.

Abstract: A magnetic head has highly thermally conductive insulator materials containing cobalt-oxide so that heat can more effectively dissipate from the magnetic head. In one illustrative example, the magnetic head has first and second gap layers and a read sensor disposed between the first and the second gap layers. The first and the second gap layers are advantageously made of cobalt-oxide (CoOx) (e.g. CoO or Co2O3), which may exhibit a thermal conductivity of between 5-8 watts/meter-Kelvin or greater. In another illustrative example, a magnetic head is made of a substrate; first and second shield layers; an undercoat layer formed between the substrate and the first shield layer; first and second gap layers formed between the first and the second shield layers; and a read sensor formed between the first and the second gap layers. The undercoat layer is also made of CoOx.

Abstract: A write head has a variable throat height wherein the throat height is dependent upon the frequency of operation of the write head. At high frequency operation the throat height is small and at low frequency operation the throat height is large. The write head writes hard into a circular track of a rotating magnetic disk at all frequencies but not overly hard at low frequencies thereby avoiding excessive erase bands and adjacent track interference (ATI) on each side of the track being written.

Abstract: A magnetic head has highly thermally conductive insulator materials containing cobalt-oxide so that heat can more effectively dissipate from the magnetic head. In one illustrative example, the magnetic head has first and second gap layers and a read sensor disposed between the first and the second gap layers. The first and the second gap layers are advantageously made of cobalt-oxide (CoOx) (e.g. CoO or Co2O3), which may exhibit a thermal conductivity of between 5-8 watts/meter-Kelvin or greater. In another illustrative example, a magnetic head is made of a substrate; first and second shield layers; an undercoat layer formed between the substrate and the first shield layer; first and second gap layers formed between the first and the second shield layers; and a read sensor formed between the first and the second gap layers. The undercoat layer is also made of CoOx.

Abstract: A magnetic head having improved overwrite capabilities and reduced fringing fields are described along with methods of making the same. The magnetic head has a first pole piece and a second pole piece. The first pole piece includes a first bottom pole piece layer, a pedestal portion formed over the first bottom pole piece layer, and a notched top pole portion formed over the pedestal portion. A gap layer separates the second pole piece from the notched top pole portion. The pedestal portion has a first saturation magnetization MS1 and the top pole portion has a second saturation magnetization MS2 that is greater than the first saturation magnetization MS1. The top pole portion has a substantially planar top surface over which a portion of the gap layer and the second pole piece are formed.