Detail Of Magnetic Shielding Patents (Class 360/319)
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Publication number: 20090316292Abstract: A magnetoresistive head is provided with high reliability and produced at a high yield rate. The magnetoresistive head includes a lower magnetic shield layer, an upper magnetic shield layer, a magnetoresistive effect film, and means for causing a current to flow in the direction of the thickness of the magnetoresistive effect film. The magnetoresistive effect film is provided between the lower magnetic shield layer and the upper magnetic shield layer. The magnetoresistive effect film is composed of a fixed layer, a non-magnetic layer, an insulating barrier layer and a free layer. The four layers of the magnetoresistive effect film are formed in this order. The insulating barrier layer is an oxide layer containing at least one of titanium and nickel.Type: ApplicationFiled: February 9, 2009Publication date: December 24, 2009Inventor: Tomio IWASAKI
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Publication number: 20090310263Abstract: A magnetic sensor comprises a nonmagnetic conductive layer, a free magnetization layer disposed on a first part of the nonmagnetic conductive layer, a fixed magnetization layer disposed on a second part of the nonmagnetic conductive layer different from the first part, upper and lower first magnetic shield layers opposing each other through the nonmagnetic conductive layer and free magnetization layer interposed therebetween, upper and lower second magnetic shield layers opposing each other through the nonmagnetic conductive layer and fixed magnetization layer interposed therebetween, and an electrically insulating layer disposed between the lower second magnetic shield layer and the nonmagnetic conductive layer, while the lower first magnetic shield layer is arranged closer to the nonmagnetic conductive layer than is the lower second magnetic shield layer.Type: ApplicationFiled: May 26, 2009Publication date: December 17, 2009Applicant: TDK CORPORATIONInventor: Tomoyuki SASAKI
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Publication number: 20090310262Abstract: A PMR writer in a read/write head is disclosed wherein an upper shield covering the coil layer is comprised of a magnetic layer optimized for magnetic performance and a second layer used for tuning mechanical protrusion. The composite layer simultaneously provides high saturation magnetization and high permeability from the magnetic layer and low CTE from the second layer which tunes the relative spacing between the writer, reader, and the rest of the slider. In one embodiment, first and second write shields are formed on a write gap layer and have front portions at the ABS and back portions in a back gap region. The upper write shield connects on one side with the second write shield at the ABS and on a second side with the back gap region. This design can yield better reader and writer spacing for the same physical clearance which enables products with higher recording density.Type: ApplicationFiled: June 12, 2008Publication date: December 17, 2009Inventors: Yan Wu, Kowang Liu
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Publication number: 20090296284Abstract: A magnetic head having an electrostatic shunt structure for preventing damage to the magnetic head during manufacture. A portion of the shunt structure is removed during manufacture, however another portion remains. In order to prevent the remaining portions of the shunt structure from picking up stray magnetic and electromagnetic fields, an electromagnetic shield, is provided between the remaining portions of the shunt structure and the substrate.Type: ApplicationFiled: May 30, 2008Publication date: December 3, 2009Inventors: Hardayal Singh Gill, Wen-Chien David Hsiao, David John Seagle
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Publication number: 20090296283Abstract: The invention provides a magnetoresistive device of the CPP (current perpendicular to plane) structure, comprising a magnetoresistive unit, and a first shield layer and a second shield layer which are located and formed such that the magnetoresistive unit is sandwiched between them with a sense current applied in a stacking direction. The magnetoresistive unit comprises a nonmagnetic intermediate layer, and a first ferromagnetic layer and a second ferromagnetic layer stacked and formed such that the nonmagnetic intermediate layer is sandwiched between them. The first shield layer and the second shield layer are each controlled by magnetization direction control means in terms of magnetization direction to create an antiparallel magnetization state where their magnetizations are in opposite directions.Type: ApplicationFiled: May 28, 2008Publication date: December 3, 2009Applicant: TDK CORPORATIONInventors: Tomohito Mizuno, Koji Shimazawa, Yoshihiro Tsuchiya
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Publication number: 20090290264Abstract: The invention provides a magnetoresistive device of the CPP (current perpendicular to plane) structure, comprising a magnetoresistive unit, and a first, substantially soft magnetic shield layer positioned below and a second, substantially soft magnetic shield layer positioned above, which are located and formed such that the magnetoresistive effect is sandwiched between them from above and below, with a sense current applied in the stacking direction. The magnetoresistive unit comprises a nonmagnetic intermediate layer, and a first ferromagnetic layer and a second ferromagnetic layer stacked and formed such that said nonmagnetic intermediate layer is sandwiched between them. At least one of the first shield layer positioned below and the second shield layer positioned above is configured in a framework form having a planar shape (X-Y plane) defined by the width and length directions of the device.Type: ApplicationFiled: May 23, 2008Publication date: November 26, 2009Applicant: TDK CORPORATIONInventors: Toshiyuki Ayukawa, Takahiko Machita, Daisuke Miyauchi, Tsutomu Chou, Koji Shimazawa, Shinji Hara, Tomohito Mizuno, Yoshihiro Tsuchiya
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Patent number: 7623322Abstract: The present invention relates to a thin-film magnetic head with a heater. A thin-film magnetic head includes a substrate, a magnetic read head element that has a shield area and is formed on the substrate, a magnetic write head element that has a pole area and is formed on the opposite side of the substrate with respect to the magnetic read head element, an overcoat layer that covers the magnetic read head element and the magnetic write head element and is formed on the substrate, a heater that heats at least during the magnetic read head element or the magnetic write head element in operation and is formed in the overcoat layer, and a slit area that splits the shield area in a shield length direction and is made of lower thermal conductivity material than the one of the shield area.Type: GrantFiled: May 13, 2005Date of Patent: November 24, 2009Assignee: TDK CorporationInventors: Tsuyoshi Umehara, Norikazu Ota, Katsumichi Tagami, Hiroki Matsukuma, Nobuya Oyama, Soji Koide, Yoshiyuki Mizoguchi, Kazuhide Yamada
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Publication number: 20090284874Abstract: A write pole structure includes a write pole having a tip region. A shield structure is spaced from the write pole by a gap at the tip region. The shield structure includes a front shield and a spacer layer on the back of the front shield. A yoke is formed on the write pole, and an end of the yoke is aligned with the back end of the spacer layer.Type: ApplicationFiled: May 19, 2008Publication date: November 19, 2009Applicant: SEAGATE TECHNOLOGY LLCInventors: Huaqing Yin, Chris J. Rea, Jianhua Xue, Steve A. Mastain
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Publication number: 20090279213Abstract: A basic design is disclosed for bottom shield (S1) and top shield (S2) of the reader shields in a magnetic read-write head. The critical part of new design includes an antiferromagnetic film which pins an antiferromagnetically coupled trilayer (AFCT). The simplest embodiment for top shield, for example, would be a film sequence of FM/Ru/FM/AFM. This replaces the normal top shield design which typically comprises a ferromagnetic seed layer and a thicker plated ferromagnetic film. Processes for manufacturing these shields are also described.Type: ApplicationFiled: May 9, 2008Publication date: November 12, 2009Inventors: Yan Wu, Glen Garfunkel, Min Li, Yuzuru Iwai, Moris Dovek
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Publication number: 20090273863Abstract: A perpendicular recording thin-film magnetic head comprises a main magnetic pole having a tip main magnetic pole part extending in a height direction from a medium-opposing surface and a base main magnetic pole part connected to the tip main magnetic pole part on a side opposite from the medium-opposing surface side and wider than the tip main magnetic pole part in a track width direction; a return yoke extending in the height direction from the medium-opposing surface and magnetically coupling with the base main magnetic pole part at a position distanced from the medium-opposing surface in the height direction, while opposing the tip main magnetic pole part through a write gap layer in a bit length direction in the medium-opposing surface; and a main magnetic pole adjacent magnetic shield layer extending along at least part of side faces of the main magnetic pole other than the medium-opposing surface as seen in a laminating direction, while holding a nonmagnetic layer between the main magnetic pole and theType: ApplicationFiled: December 13, 2007Publication date: November 5, 2009Applicants: TDK CORPORATION, SAE MAGNETICS (H.K.) LTD.Inventors: Hidetaka Kawano, Hiromichi Umehara, Takamitsu Sakamoto, Koichi Otani, Noriaki Kasahara, Naoto Matono
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Publication number: 20090273864Abstract: A magnetoresistive element includes a first and a second shield, and an MR stack disposed between the shields. The MR stack includes a first and a second ferromagnetic layer, and a nonmagnetic spacer layer disposed between the ferromagnetic layers. The first and second ferromagnetic layers have magnetizations that are in directions antiparallel to each other when no external magnetic field is applied to the layers, and that change directions in response to an external magnetic field. An insulating layer is formed to touch a rear end face of the MR stack and the first shield, and a bias magnetic field applying layer is formed above the insulating layer with a buffer layer disposed in between. The bias magnetic field applying layer includes a hard magnetic layer and a high saturation magnetization layer. The high saturation magnetization layer is located between the rear end face and the hard magnetic layer, but not located between the first shield and the hard magnetic layer.Type: ApplicationFiled: December 27, 2007Publication date: November 5, 2009Applicant: TDK CORPORATIONInventors: Takahiko Machita, Kei Hirata, Koji Shimazawa, Daisuke Miyauchi
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Publication number: 20090268350Abstract: A magnetic write head having a trailing shield configured to optimize both write field strength and field gradient. The write head includes a write pole, a trailing gap layer formed over the trailing edge of the write pole and a trailing magnetic shield formed over the non-magnetic write gap layer such that the non-magnetic write gap layer is sandwiched between the trailing magnetic shield and the write pole. The trailing magnetic shield has a first surface disposed at the air bearing surface and second surface disposed away from the air bearing surface that is tapered at an angle of 20 to 75 degrees relative to the trailing edge of the write pole.Type: ApplicationFiled: April 25, 2008Publication date: October 29, 2009Inventors: Wen-Chien David Hsiao, Vladimir Nikitin
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Publication number: 20090262465Abstract: Embodiments of the present invention provide a magnetic head having a read head of stable reading operation and with less magnetic fluctuation noise. According to one embodiment, a free layer has a structure comprising two ferromagnetic layers (a first free layer and a second free layer) that are coupled anti-ferromagnetically by way of a non-magnetic intermediate layer, in which the magnetization amount of the first free layer is set to larger than the magnetization amount of the second free layer. Further, the magnetic domains in the first free layer and the second free layer are stabilized simultaneously by increasing the distance between the second free layer and the magnetic domain control film to be more than the distance between the first free layer and the magnetic domain control film, thereby adjusting the magnetization amount of the magnetic domain control film.Type: ApplicationFiled: April 17, 2009Publication date: October 22, 2009Inventors: Masahiko Hatatani, Katsuro Watanabe, Nubuo Yoshida, Katsumi Hoshino
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Publication number: 20090262464Abstract: A magnetic write head for perpendicular magnetic recording having a trailing, wrap around magnetic shield constructed of a low magnetic permeability. The lower permeability of the shield prevents magnetic saturation of the shield, which in turn prevents adjacent track interference such as adjacent track erasure. The shield can also be constructed as a pure trailing shield, or as first and second side shields without any trailing shield portion.Type: ApplicationFiled: April 21, 2008Publication date: October 22, 2009Inventors: Hardayal Singh Gill, Wen-Chien David Hsiao
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Patent number: 7606006Abstract: Embodiments of the invention provide a write head for perpendicular recording in which the magnetic field intensity applied at a read element is reduced with larger write-field gradients and the distance between a write element and a read element is small. In one embodiment, a pair of magnetic bodies for shielding a read element are provided on the leading and trailing sides of the read element respectively and whichever one of the two shields is the longer in the length from the air bearing surface is shorter than the length up to the back contact position PBK at which a main pole and an auxiliary pole are connected.Type: GrantFiled: December 15, 2004Date of Patent: October 20, 2009Assignee: Hitachi Global Storage Technologies Netherlands B.V.Inventors: Masafumi Mochizuki, Kaori Suzuki, Kimitoshi Etoh
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Patent number: 7606007Abstract: Apparatus and method for providing a magnetic head that includes a magnetoresistive read sensor disposed between first and second magnetic shields. The shields are configured to reduce protrusion of the shields from a polished flat air bearing surface of the magnetic head upon increases in temperature. This configuration for the shields therefore at least reduces differences in thermal expansion of the shields relative to other parts of the magnetic head forming the air bearing surface. These shields according to some embodiments include one or more ferromagnetic layers exchange coupled with an antiferromagnetic layer. Further, in a particular embodiment, all the ferromagnetic layers within each of the shields can have a combined thickness per shield of less than 500 angstroms.Type: GrantFiled: February 17, 2006Date of Patent: October 20, 2009Assignee: Hitachi Global Storage Technologies Netherlands B.V.Inventor: Hardayal Singh Gill
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Publication number: 20090257153Abstract: We disclose a magnetic read head, and method for making it, that operates in a binary rather than an analog mode. This greatly boosts signal amplitude for high area density recording as device dimensions get smaller. The device is well suited to the inclusion of side shields which further reduces side reading errors.Type: ApplicationFiled: April 10, 2008Publication date: October 15, 2009Inventor: Yue Liu
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Publication number: 20090251829Abstract: A composite seed layer that reduces the shield to shield distance in a read head while improving Hex and Hex/Hc is disclosed and has a SM/A/SM/B configuration in which the SM layers are soft magnetic layers, the A layer is made of at least one of Co, Fe, Ni, and includes one or more amorphous elements, and the B layer is a buffer layer that contacts the AFM layer in the spin valve. The SM/A/SM stack together with the S1 shield forms an effective shield such that the buffer layer serves as the effective seed layer with a thickness as low as 5 Angstroms while maintaining a blocking temperature of 260° C. in the AFM layer. The lower SM layer may be omitted. Examples of the amorphous layer are CoFeB, CoFeZr, CoFeNb, CoFeHf, CoFeNiZr, CoFeNiHf, and CoFeNiNbZr while the buffer layer may be Cu, Ru, Cr, Al, or NiFeCr.Type: ApplicationFiled: April 2, 2008Publication date: October 8, 2009Inventors: Kunliang Zhang, Tong Zhao, Hui-Chuan Wang, Min Li
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Publication number: 20090251828Abstract: A vertically stacked DFH design in a read/write head is disclosed that allows independent control of write gap protrusion and read gap protrusion. A first heater is formed in an insulation layer proximate to a sensor in a read head. A second heater is formed in a second insulation layer proximate to the write pole tip in a main pole layer. The two heaters are connected in series or in parallel through leads to a power source that activates the heaters. In one embodiment, the heaters have a fixed resistance ratio. Preferably, there are two drivers in the power source so that a first power can be applied to the first heater and a second power can be applied to the second heater to enable an adjustment of reader protrusion/writer protrusion or gamma ratio. Fast reader and writer actuation is achieved and low power consumption is realized.Type: ApplicationFiled: April 2, 2008Publication date: October 8, 2009Inventors: Erhard Schreck, Kowang Liu
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Patent number: 7599153Abstract: A method and apparatus providing a stabilized top shield in a read head used for the longitudinal or perpendicular magnetic recording is disclosed. The top shield includes a laminate structure including at least three layers of ferromagnetic and antiferromagnetic films in a frame. Unidirectional anisotropy induced at the interface of the ferromagnetic and antiferromagnetic films is optimized by selecting suitable compositions and thicknesses to achieve the stabilization of the top shield while maintaining high permeability. In an alternative method, the top shield includes a ferromagnetic Ni—Fe film in a central region and multiple layers comprising ferromagnetic Co—Fe and Ni—Fe layers and an antiferromagnetic layer.Type: GrantFiled: February 27, 2006Date of Patent: October 6, 2009Assignee: Hitachi Global Storage Technologies Netherlands B.V.Inventor: Tsann Lin
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Patent number: 7599152Abstract: 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.Type: GrantFiled: April 28, 2005Date of Patent: October 6, 2009Assignee: Headway Technologies, Inc.Inventors: Lijie Guan, Moris Dovek
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Patent number: 7599151Abstract: Embodiments of the invention provide a magnetic recording and read head which reduces the spread read width in a narrow track having a width of 100 nm or less and shows stable read operation. In one embodiment, a side magnetic shield has a multi-layered structure including non-magnetic separate layers and soft magnetic layers, and the soft magnetic layers are magnetized in opposite directions to reduce a magnetic field induced by the side magnetic shield.Type: GrantFiled: October 29, 2004Date of Patent: October 6, 2009Assignee: Hitachi Global Storage Technologies Netherlands B.V.Inventors: Masahiko Hatatani, Chiseki Haginoya, Kenichi Meguro, Kazuhiro Nakamoto
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Patent number: 7583478Abstract: A thin-film magnetic head comprises: a magnetoresistive element: first and second read shield layers disposed to sandwich the magnetoresistive element; and bias field applying layers for applying a bias magnetic field to the magnetoresistive element. Each of the first and second read shield layers has: a first end face located in a medium facing surface; a second end face opposite to the first end face; a first width changing portion that continuously decreases in width as the distance from the first end face decreases; and a second width changing portion that continuously decreases in width as the distance from the second end face decreases.Type: GrantFiled: July 7, 2006Date of Patent: September 1, 2009Assignee: TDK CorporationInventors: Takahiko Machita, Kei Hirata, Koji Shimazawa
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Publication number: 20090213502Abstract: A magneto-resistance effect element comprises: a magneto-resistance effect stack including an upper magnetic layer and a lower magnetic layer whose magnetization directions change in accordance with an external magnetic field, a non-magnetic intermediate layer sandwiched between the upper and lower magnetic layers; an upper shield electrode layer and a lower shield electrode layer which are provided to sandwich the magneto-resistance effect stack therebetween in the direction of stacking the magneto-resistance effect stack, wherein the upper shield electrode layer and the lower shield electrode layer supply sense current in the direction of stacking, and magnetically shield the magneto-resistance effect stack; a first bias magnetic layer which is provided on a surface of the magneto-resistance effect stack opposite to an air bearing surface, and wherein the first bias magnetic layer is magnetized in a direction perpendicular to said air bearing surface; and a pair of second bias magnetic layers provided on reType: ApplicationFiled: February 25, 2008Publication date: August 27, 2009Inventors: Daisuke MIYAUCHI, Koji SHIMAZAWA, Tsutomu CHOU, Takahiko MACHITA, I
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Patent number: 7573683Abstract: A write head for a media drive suited for perpendicularly recording data in adjacent magnetic recording media, the media having a magnetic recording layer and a soft underlayer (SUL). The write head has a pole tip, a write yoke connected to the pole tip, a write return yoke, a write shield, one or more conductive coils surrounding the write yoke, and one or more side shields disposed in close proximity to the pole tip. The write return yoke connects to the write yoke on one end and the write shield on a different end. The one or more side shields are separated from the pole tip and write shields by a non-magnetic material and therefore are “floating” and not directly coupled to the write shield or pole tip.Type: GrantFiled: July 6, 2006Date of Patent: August 11, 2009Assignee: Maxtor CorporationInventors: Mourad Benakli, Michael Mallary
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Publication number: 20090195940Abstract: In the magnetic head, terminal sections for mutually electrically connecting layers in the multilayer structure can be formed without forming raising layers. The magnetic head having a multilayer structure comprises: an upper shielding layer; a lower shielding layer; a magnetoresistance effect element section provided between the shielding layers; a magnetic pole; terminal sections mutually electrically connecting layers of the multilayer structure; and a first low-thermal expansion material layer composed of an insulating material, and each of the terminal sections has a multilayer structure comprising: a second low-thermal expansion material layer composed of a material which is the same as that of the first low-thermal expansion material layer; and a plurality of electrically conductive layers.Type: ApplicationFiled: October 3, 2008Publication date: August 6, 2009Applicant: FUJITSU LIMITEDInventors: Junji Sato, Takashi Ito
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Publication number: 20090190271Abstract: An MR element includes a first ferromagnetic layer, a second ferromagnetic layer, a spacer layer disposed between the first and second ferromagnetic layers; and an antiferromagnetic layer disposed on a side of the first ferromagnetic layer farther from the spacer layer. The antiferromagnetic layer is disposed away from a detection surface. The first ferromagnetic layer includes: a first portion having an end face located in the detection surface and a rear end opposite to the end face; and a second portion located away from the detection surface and connected to the rear end of the first portion. The first portion has a first surface touching the spacer layer, and a second surface that is opposite to the first surface and that does not touch the antiferromagnetic layer. The second portion has a third surface touching the antiferromagnetic layer, and a fourth surface opposite to the third surface.Type: ApplicationFiled: January 28, 2008Publication date: July 30, 2009Applicant: TDK CORPORATIONInventors: Hiroshi Yamazaki, Naoki Ohta
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Publication number: 20090190272Abstract: The invention provides a magnetoresistive device with the CPP (current perpendicular to plane) structure, comprising a magnetoresistive unit, and a first shield layer and a second shield layer located and formed such that the magnetoresistive unit is sandwiched between them, with a sense current applied in a stacking direction, wherein said magnetoresistive unit comprises a nonmagnetic intermediate layer, and a first ferromagnetic layer and a second ferromagnetic layer stacked and formed such that said nonmagnetic intermediate layer is interposed between them, wherein said first shield layer, and said second shield layer is controlled by magnetization direction control means in terms of magnetization direction, and said first ferromagnetic layer, and said second ferromagnetic layer receives action such that there is an antiparallel magnetization state created, in which mutual magnetizations are in opposite directions, under the influences of magnetic actions of said first shield layer and said second shield lType: ApplicationFiled: January 24, 2008Publication date: July 30, 2009Applicant: TDK CorporationInventors: Takahiko Machita, Koji Shimazawa, Daisuke Miyauchi, Tsutomu Chou
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Publication number: 20090190268Abstract: A magnetoresistive device of a CPP (current perpendicular to plane) structure includes a magnetoresistive unit sandwiched between a first substantially soft magnetic shield layer from below, and a second substantially soft magnetic shield layer from above, with a sense current applied in a stacking direction. The magnetoresistive unit includes a non-magnetic intermediate layer sandwiched between a first ferromagnetic layer, and a second ferromagnetic layer. At least one of the first and second shield layers is configured in a window frame of a planar shape, including a front frame-constituting portion and a back frame-constituting portion partially comprising a combination of a nonmagnetic gap layer with a bias magnetic field-applying layer. The combination of the nonmagnetic gap layer with the bias magnetic field-applying layer forms a closed magnetic path with magnetic flux going all the way around the window framework, turning the magnetization of the front frame-constituting portion into a single domain.Type: ApplicationFiled: January 24, 2008Publication date: July 30, 2009Applicant: TDK CorporationInventors: Takahiko Machita, Koji Shimazawa, Daisuke Miyauchi, Tsutomu Chou
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Patent number: 7565732Abstract: A method of fabricating a magnetic write head, in accordance with one embodiment, includes forming a beveled write pole. A conformal spacer may be formed upon a portion of a flare length proximate a tip of the write pole. A shield layer may also be formed upon the conformal spacer adjacent the flare length proximate the tip of the write pole.Type: GrantFiled: August 31, 2004Date of Patent: July 28, 2009Assignee: Hitachi Global Storage Technologies Netherlands B.V.Inventors: Quang Le, Howard Zolla, Nian-Xiang Sun
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Patent number: 7562436Abstract: In one embodiment, a method of forming a CPP sensor comprises providing a sensor having a hard mask disposed on a left side thereof and a right side with a portion of the sensor material removed therefrom, the hard mask having a vertical surface; forming a right dielectric layer including a vertical surface disposed adjacent the vertical surface of the hard mask; forming a right hard bias layer or right side shields on the right dielectric layer; removing the hard mask to expose the left side of the sensor; forming an electrically conductive layer on the sensor, the electrically conductive layer including a vertical electrically conductive portion disposed adjacent the vertical surface of the right dielectric layer; removing the electrically conductive layer except the vertical electrically conductive portion; removing a portion of the sensor material from the left side of the sensor; forming a left dielectric layer on the left side of the sensor, the left dielectric layer including a vertical surface disposeType: GrantFiled: July 29, 2005Date of Patent: July 21, 2009Assignee: Hitachi Global Storage Technologies Netherlands B.V.Inventor: Wipul Pemsiri Jayasekara
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Patent number: 7564236Abstract: A method for testing magnetic heads formed on a wafer to detect the presence of thermal induced popcorn noise resulting from thermal fly height control. The method includes performing a quasi test on a magnetic head, the quasi test being performed over 400 or more cycles of magnetic field application. For additional test accuracy, the write head can be cycled while 400 or more cycles of magnetic field are generated.Type: GrantFiled: July 1, 2008Date of Patent: July 21, 2009Assignee: Hitachi Global Storage Technologies Netherlands B.V.Inventors: David Ernest Call, Hardayal Singh Gill
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Patent number: 7561380Abstract: A transducing head has a main pole and at least one magnetic element (such as a return pole or a shield) which provides a potential return path for a magnetic field produced by the main pole. The magnetic element is spaced from the main pole. The magnetic element has a first edge closest to the main pole and a second edge furthest from the main pole. Permeability of the magnetic element increases from the first edge to the second edge.Type: GrantFiled: April 10, 2008Date of Patent: July 14, 2009Assignee: Seagate Technology LLCInventors: Nurul Amin, Yuming Zhou, Kaizhong Gao, Patrick J. Ryan, Steven Kalderon, Song S. Xue, Shaoping Li, Mark T. Kief
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Publication number: 20090174968Abstract: A magnetic sensor assembly includes first and second shields each comprised of a magnetic material. The first and second shields define a physical shield-to-shield spacing. A sensor stack is disposed between the first and second shields and includes a seed layer adjacent the first shield, a cap layer adjacent the second shield, and a magnetic sensor between the seed layer and the cap layer. At least a portion of the seed layer and/or the cap layer comprises a magnetic material to provide an effective shield-to-shield spacing of the magnetic sensor assembly that is less than the physical shield-to-shield spacing.Type: ApplicationFiled: January 9, 2008Publication date: July 9, 2009Applicant: SEAGATE TECHNOLOGY LLCInventors: Eric W. Singleton, Qing He, Jae-Young Yi, Matt Johnson, Zheng Gao, Dimitar V. Dimitrov, Song S. Xue
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Patent number: 7558027Abstract: A magnetic field sensor comprises: a magnetic field detecting element that detects magnitude of an external magnetic field based on electric resistance of the magnetic field detecting element to sense current, the electric resistance being varied in accordance with the external magnetic field; an upper shield layer that is formed to cover the magnetic field detecting element; and a protective layer that is formed above the upper shield layer with respect to a direction of stacking. The upper shield layer includes a first portion at least part of which covers a top surface of the magnetic field detecting element, and a second portion that covers the first portion, and, the first portion has a larger absolute value of magnetostriction than the second portion.Type: GrantFiled: April 26, 2006Date of Patent: July 7, 2009Assignee: TDK CorporationInventors: Kei Hirata, Takahiko Machita, Koji Shimazawa, Kiyoshi Noguchi
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Publication number: 20090168257Abstract: A magnetic write head for perpendicular magnetic recording. The magnetic write head includes a write pole having a pole tip region and a flared region. The write pole also has a trailing, wrap-around magnetic shield that is separated from the sides of the write pole by a non-magnetic side gap layer. The write head is formed such that the side gap spacing is larger in the flared region than in the pole tip region. This varying gap spacing can be formed by depositing a non-magnetic material using a collimated sputter deposition aligned substantially perpendicular to the air bearing surface. This collimated sputtering deposits the non-magnetic material more readily on the sides of the write pole in the flared region than in the pole tip region.Type: ApplicationFiled: December 28, 2007Publication date: July 2, 2009Inventors: Wen-Chien David Hsiao, Yinshi Liu, Yi Zheng
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Publication number: 20090168256Abstract: Read elements and associated methods of fabrication are disclosed. A read element as described herein includes a magnetoresistance (MR) sensor sandwiched between first and second shields. The read element uses the first shield as an active portion of the MR sensor. Instead of implementing an AFM pinning layer in the MR sensor, the first shield takes the place of the AFM pinning layer. The first shield is orthogonally coupled to the pinned layer through an orthogonal coupling layer, such as a thin layer of AFM material. Through this structure, the magnetic moment of the first shield pins the magnetic moment of the pinned layer transverse to the ABS of the read element, and an AFM pinning layer is not needed.Type: ApplicationFiled: December 27, 2007Publication date: July 2, 2009Inventors: Daniele Mauri, Neil Smith
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Publication number: 20090166184Abstract: A track shield structure is disclosed that enables higher track density to be achieved in a patterned track medium without increasing adjacent track erasure and side reading. This is accomplished by placing a soft magnetic shielding structure in the space that is present between the tracks in the patterned medium. A process for manufacturing the added shielding structure is also described.Type: ApplicationFiled: December 26, 2007Publication date: July 2, 2009Inventors: Yuchen Zhou, Lijie Guan, Kunliang Zhang
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Publication number: 20090168260Abstract: Methods and structures for the fabrication of both thin film longitudinal and perpendicular write heads are disclosed. A unique feature of these write heads is the inclusion of layered return poles, which comprise alternating layers of 22/78 and 80/20 NiFe alloys. The alternating layers also vary in thickness, the 22/78 NiFe layers having a nominal thickness of 1500 angstroms and the 80/20 NiFe layers having a nominal thickness of about 75 angstroms. Head efficiency and signal to noise ratios are significantly improved in heads having layered return pole construction.Type: ApplicationFiled: December 26, 2007Publication date: July 2, 2009Inventors: Donald G. Allen, Hieu Lam, Terence Tin-Lok Lam, Steve C. Puga
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Publication number: 20090168258Abstract: A magnetic write head for perpendicular magnetic recording. The write head has a secondary flare point defined by magnetic structures that extend from the sides of the write pole, but not over the trailing edge of the write pole. The magnetic structures each have a front edge that defines the secondary flare point. By constructing the magnetic structures so that they only extend from the sides of the write pole and not over the write pole, they can be formed by electroplating, while leafing the mask structure (used to define the write pole) still intact, thereby greatly simplifying manufacture and preventing damage to the write pole during manufacture.Type: ApplicationFiled: December 28, 2007Publication date: July 2, 2009Inventors: Quang Le, Jeffrey S. Lille, Aron Pentek
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Publication number: 20090168259Abstract: Embodiments of the invention provide methods, systems and apparatus for testing electronic components, and more specifically for testing magnetoresistive heads. A pair of top shield pads and a pair of bottom shield pads may be formed in a kerf region of a wafer on which magnetoresistive heads are formed. The top shield pads, bottom shield pads, and a magnetoresistive head may form a circuit that may be coupled with a testing circuit to exchange test signals configured to test the magnetic head. The pair of bottom shield pads may provide balanced impedance to substrate that nullifies the effects of broadband noise.Type: ApplicationFiled: December 31, 2007Publication date: July 2, 2009Inventors: ARLEY CLEVELAND MARLEY, David John Seagle
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Publication number: 20090168261Abstract: A magnetoresistive element is located between a lower shielding layer and an upper shielding layer. The magnetoresistive element receives an electric current through the lower shielding layer and the upper shielding layer. A non-magnetic conductive layer is embedded in the insulating film between the slider body and the lower shielding layer. An air layer is formed between the head slider and a storage medium. Capacitive coupling is established between the head slider and the storage medium. The capacitive coupling allows transmission of the noise from the storage medium to the slider body. The noise affects capacitance established between the lower shielding layer and the slider body. The non-magnetic conductive layer serves to prevent variation in a potential difference resulting from transmission of the noise between the lower shielding layer and the upper shielding layer.Type: ApplicationFiled: September 3, 2008Publication date: July 2, 2009Applicant: FUJITSU LIMITEDInventors: Sachiko Furuya, Tetsuyuki Kubota, Junichi Hashimoto, Tomoka Aoki
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Publication number: 20090161263Abstract: Embodiments of the present invention provide a magnetic head for perpendicular magnetic recording, and a magnetic disk apparatus capable of preventing data erasure caused by alignment marks. In an embodiment, the magnetic head includes a head element including at least a main pole having a pole face on a flying surface and an auxiliary pole; alignment marks made of a magnetic material and used to detect the amount of lapping work when lapping the pole face of the main pole; and members made of a magnetic material, continuously extending in either direction with respect to the position of the main pole from within the alignment marks outward at least beyond the alignment marks.Type: ApplicationFiled: December 3, 2008Publication date: June 25, 2009Inventors: Mao Nishiyama, Shuji Nishida, Hideaki Maeda, Masafumi Mochizuki
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METHOD FOR MANUFACTURING A PERPENDICULAR MAGNETIC WRITE HEAD WITH A THIN WRAP AROUND MAGNETIC SHIELD
Publication number: 20090154026Abstract: A magnetic write head for perpendicular magnetic recording having a thin wrap-around magnetic shield. The small thickness and forming method of the thin wrap-around magnetic shield allow it to be electroplated using a thin photoresist frame mask. The thin photoresist frame mask has better critical dimension and straight wall control than a thicker mask, which allows the wrap-around magnetic shield to be constructed with much more straight and uniform back edge for shield throat height control than is possible when forming a thicker (i.e. taller) shield. The thin wrap-around magnetic shield can be stitched to a trailing return pole to avoid magnetic saturation of the wrap-around shield.Type: ApplicationFiled: December 12, 2007Publication date: June 18, 2009Inventors: Ming Jiang, Changqing Shi -
Publication number: 20090154027Abstract: Read sensors and associated methods of fabrication are disclosed. A read sensor as disclosed herein includes a first shield, a sensor stack including an antiparallel (AP) free layer, and insulating material disposed on the sensor stack. A aperture is formed through the insulating material above the sensor stack so that a subsequently deposited second shield is electrically coupled to the sensor stack through the aperture. The width of the aperture controls the current density that is injected into the top of the sensor stack. Also, hard bias structures may be formed to be electrically coupled to the sensor stack. The electrical coupling of the sensor stack and the hard bias structures allows current to laterally spread out as it passes through the sensor stack, and hence, provides a non-uniform current density.Type: ApplicationFiled: December 16, 2007Publication date: June 18, 2009Inventors: Hamid Balamane, Jeffrey R. Childress, Robert E. Fontana, JR., Jordan A. Katine, Neil Smith
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Publication number: 20090151151Abstract: Methods of fabricating magnetic read heads are provided which reduce the width of the scratch exposure region of a read head. During normal fabrication processes, a read head is formed with a first shield, a read element formed on the first shield, and hard bias layers formed on either side of the read element. The width of the read elements and the hard bias layers define an initial scratch exposure region. According to embodiments herein, a mask structure is formed to protect the read element and first portions of the hard bias layers proximate to the read element. A removal process is then performed to remove second portions of the hard bias layers that are not protected by the mask structure, which defines a final scratch exposure region that is smaller than the initial scratch exposure region.Type: ApplicationFiled: December 16, 2007Publication date: June 18, 2009Inventors: David P. Druist, Mohamad T. Krounbi, David J. Seagle
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Publication number: 20090154030Abstract: Embodiments of the present invention provide an accumulation element with high resolving power and high output suitable for magnetic recording and reproducing at high recording density. According to one embodiment, a plurality of spin injection parts and are provided to increase the total amount of spin electrons. The spin accumulation element is composed of a non-magnetic conductor, a first magnetic conductor, a second magnetic conductor, and a third magnetic conductor, each of which are in contact with the non-magnetic conductor through the tunneling junction. An output voltage due to the spin accumulation effect is detected as a potential difference between the non-magnetic conductor and the third magnetic conductor.Type: ApplicationFiled: December 3, 2008Publication date: June 18, 2009Inventors: Masaki Yamada, Hiromasa Takahashi
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Publication number: 20090154028Abstract: A head for a hard disk drive. The head includes a substrate, a write element, a read element and a heater element. The head also includes a buffer layer between the read element and the substrate, and a first resistor connected to the heater element and the buffer layer. The buffer layer and resistor create an impedance that suppresses noise introduced to the head from the disk of the drive.Type: ApplicationFiled: December 12, 2007Publication date: June 18, 2009Applicant: Samsung Electronics Co., Ltd.Inventor: Eunkyu Jang
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Publication number: 20090154029Abstract: A magnetic reproduction head includes a lower magnetic shield layer, an upper magnetic shield layer, a magnetoresistive film formed between the lower and the upper magnetic shield layers, a refill film in an element height direction disposed in contact with a surface opposite a floating surface of the magnetoresistive film, and a refill film in a track width direction disposed on a side wall surface of the magnetoresistive film. The magnetoresistive film is a tunneling magnetoresistive film including a free layer, an insulating barrier layer, and a fixed layer. The insulating barrier layer is one of a magnesium oxide film, an aluminum oxide film, and a titanium oxide film which contains at least one of nitrogen and silicon.Type: ApplicationFiled: November 17, 2008Publication date: June 18, 2009Inventor: Tomio IWASAKI
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Publication number: 20090147410Abstract: A perpendicular magnetic recording write head that may be used in magnetic recording disk drives has a magnetic write pole (WP) with an end that is generally the same width as the width of the data tracks on the disk. A trailing shield (TS) is spaced from the WP in the along-the-track direction, a pair of side shields are located on opposite sides of the WP in the cross-track direction, and an optional leading shield (LS) is located on the opposite side of the WP from the TS in the along-the-track direction. The TS, side shields and LS are formed of magnetically permeable soft ferromagnetic material and are separated from each other by nonmagnetic separation layers. The TS, side shields and LS each has a throat height (TH) thickness in its region facing the WP. The throat heights for the shields may be different.Type: ApplicationFiled: December 6, 2007Publication date: June 11, 2009Applicant: HITACHI GLOBAL STORAGE TECHNOLOGIES NETHERLANDS B.V.Inventors: Ming Jiang, Changqing Shi