Patents by Inventor Samuel W. Yuan
Samuel W. Yuan has filed for patents to protect the following inventions. This listing includes patent applications that are pending as well as patents that have already been granted by the United States Patent and Trademark Office (USPTO).
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Patent number: 9142233Abstract: A heat assisted magnetic recording (HAMR) write transducer has an air-bearing surface (ABS) configured to reside in proximity to a media during use and is coupled with a laser that provides energy. The HAMR transducer includes a main pole, at least one additional pole adjacent to the main pole in a down track direction, a waveguide and at least one coil for energizing the main pole. The main pole is configured to write to a region of the media and is recessed from the ABS by a first distance. The additional pole(s) are recessed from the ABS by a second distance greater than the first distance. The waveguide is optically coupled with the laser and directs a portion of the energy toward the ABS at an acute angle from the ABS. A portion of the waveguide resides between the additional pole(s) and the ABS.Type: GrantFiled: June 6, 2014Date of Patent: September 22, 2015Assignee: Western Digital (Fremont), LLCInventors: Matthew R. Gibbons, Hongxing Yuan, Brad V. Johnson, Michael V. Morelli, Lisha Wang, Zhigang Bai, Ge Yi, Yunfei Li, Samuel W. Yuan
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Patent number: 9082423Abstract: A magnetic transducer has an ABS, a pole, coil(s) and a trailing shield. The pole includes a trailing surface having first and second portions. The first portion adjoins the ABS and is oriented at a first bevel angle from perpendicular to the ABS. The first bevel angle is nonzero and acute. The second portion adjoins the first portion, is recessed from the ABS and oriented at a second bevel angle from perpendicular to the ABS. The second bevel angle is less than the first bevel angle and nonzero. The trailing shield has a pole-facing surface part of which adjoins the ABS and is oriented at the first bevel angle. A write gap is between the trailing shield and the pole. The write gap has a constant thickness for the first portion of the trailing surface and a thickness that increases with increasing distance from the ABS for the second portion.Type: GrantFiled: March 24, 2014Date of Patent: July 14, 2015Assignee: Western Digital (Fremont), LLCInventors: Feng Liu, Zhigang Bai, Weimin Si, Yugang Wang, Fenglin Liu, Tao Pan, Samuel W. Yuan
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Patent number: 8947985Abstract: A heat assisted magnetic recording (HAMR) write transducer has an air-bearing surface (ABS) configured to reside in proximity to a media during use and is coupled with a laser that provides energy. The HAMR transducer includes a main pole, at least one additional pole adjacent to the main pole in a down track direction, a waveguide and at least one coil for energizing the main pole. The main pole is configured to write to a region of the media and is recessed from the ABS by a first distance. The additional pole(s) are recessed from the ABS by a second distance greater than the first distance. The waveguide is optically coupled with the laser and directs a portion of the energy toward the ABS at an acute angle from the ABS. A portion of the waveguide resides between the additional pole(s) and the ABS.Type: GrantFiled: September 23, 2013Date of Patent: February 3, 2015Assignee: Western Digital (Fremont), LLCInventors: Michael V. Morelli, Lisha Wang, Zhigang Bai, Hongxing Yuan, Yunfei Li, Zhanjie Li, Matthew R. Gibbons, Samuel W. Yuan
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Patent number: 8617408Abstract: A method for manufacturing a magnetic read sensor at very narrow track widths. The method uses an amorphous carbon mask layer to pattern the sensor by ion milling, rather than a mask constructed of a material such as photoresist or DURIMIDE® which can bend over during ion milling at very narrow track widths. By using the amorphous carbon layer as the masking layer, the trackwidth can be very small, while avoiding this bending over of the mask that has been experienced with prior art methods. In addition, the track-width can be further reduced by using a reactive ion etching to further reduce the width of the amorphous carbon mask prior to patterning the sensor. The method also allows extraneous portions of the side insulation layer and hard bias layer to be removed above the sensor by a light CMP process.Type: GrantFiled: October 18, 2011Date of Patent: December 31, 2013Assignee: HGST Netherlands B.V.Inventors: Hamid Balamane, Patrick M. Braganca, Jordan A. Katine, Jui-Lung Li, Yang Li, Kanaiyalal C. Patel, Neil L. Robertson, Samuel W. Yuan
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Publication number: 20130092654Abstract: A method for manufacturing a magnetic read sensor at very narrow track widths. The method uses an amorphous carbon mask layer to pattern the sensor by ion milling, rather than a mask constructed of a material such as photoresist or DURIMIDE® which can bend over during ion milling at very narrow track widths. By using the amorphous carbon layer as the masking layer, the trackwidth can be very small, while avoiding this bending over of the mask that has been experienced with prior art methods. In addition, the track-width can be further reduced by using a reactive ion etching to further reduce the width of the amorphous carbon mask prior to patterning the sensor. The method also allows extraneous portions of the side insulation layer and hard bias layer to be removed above the sensor by a light CMP process.Type: ApplicationFiled: October 18, 2011Publication date: April 18, 2013Applicant: Hitachi Global Storage Technologies Netherlands B.V.Inventors: Hamid Balamane, Patrick M. Braganca, Jordan A. Katine, Jui-Lung Li, Yang Li, Kanaiyalal C. Patel, Neil L. Robertson, Samuel W. Yuan
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Patent number: 8335053Abstract: In one general embodiment, a magnetic head includes a touch-down pad, comprising at least one shielding element positioned between a leading edge of a main magnetic pole and a trailing edge of a lower return pole; an embedded contact sensor (ECS) in an electrically isolating layer, the ECS positioned near an ABS side of the magnetic head and between the leading edge of the main magnetic pole and the trailing edge of the lower return pole; and a first thermal fly-height control (TFC) element positioned away from the ABS side of the magnetic head. Additional systems and methods are also presented.Type: GrantFiled: October 28, 2010Date of Patent: December 18, 2012Assignee: Hitachi Global Storage Technologies Netherlands B.V.Inventors: Yingjian Chen, David J. Seagle, Samuel W. Yuan
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Publication number: 20120105999Abstract: In one general embodiment, a magnetic head includes a touch-down pad, comprising at least one shielding element positioned between a leading edge of a main magnetic pole and a trailing edge of a lower return pole; an embedded contact sensor (ECS) in an electrically isolating layer, the ECS positioned near an ABS side of the magnetic head and between the leading edge of the main magnetic pole and the trailing edge of the lower return pole; and a first thermal fly-height control (TFC) element positioned away from the ABS side of the magnetic head. Additional systems and methods are also presented.Type: ApplicationFiled: October 28, 2010Publication date: May 3, 2012Applicant: Hitachi Global Storage Technologies Netherlands B.V.Inventors: Yingjian Chen, David J. Seagle, Samuel W. Yuan
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Reduction of interference pickup in heads for magnetic recording by minimizing parasitic capacitance
Patent number: 7573677Abstract: Disclosed is a system and a method for reducing high frequency interference pickup by the read element of the magneto-recording head. The reduction is achieved by reducing the parisitic capacitance between certain elements of the magnetic head. In one embodiment, the areas of the pads and leads, including the areas of the leads over the S1 and the areas of the sensor leads, are reduced. A second implementation involves increasing the separation between the pads and leads and the substrate material. Copper studs or vias may be used to connect the contact pads and the underlying layers. A third implementation includes using a low dielectric constant material as a spacer layer between conductors (leads, pads, magnetic shields) and the substrate.Type: GrantFiled: March 1, 2002Date of Patent: August 11, 2009Assignee: International Business Machines CorporationInventors: Vladimir Nikitin, Michael Paul Salo, Samuel W. Yuan, Robert Langland Smith, Mark Allen Burleson -
Patent number: 7092206Abstract: A magnetic head includes a magnetic write structure having a first magnetic layer having a first pole, a second magnetic layer having a second pole spaced apart from the first pole, and a third magnetic layer having a third pole contacting the second pole. The third pole has a third-pole width greater than a second-pole width. An inductive coil positioned adjacent to the third magnetic layer controllably magnetizes the third magnetic layer. The third magnetic layer is nonuniformly thick such that a thickness of the third pole is less than a thickness of the third magnetic layer at locations in registry with the inductive coil. The magnetic write structure is conveniently fabricated by depositing the magnetic layers and the inductive coil, masking the third magnetic layer other than the third pole, and removing a portion of the thickness of the third pole.Type: GrantFiled: June 25, 2003Date of Patent: August 15, 2006Assignee: Hitachi Global Storage Technologies Netherlands B.V.Inventors: Wen-Chien D. Hsiao, Hin P. E. Lee, Jyh-Shuey Lo, Yansheng Luo, Samuel W. Yuan
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Publication number: 20040264046Abstract: A magnetic head includes a magnetic write structure having a first magnetic layer having a first pole, a second magnetic layer having a second pole spaced apart from the first pole, and a third magnetic layer having a third pole contacting the second pole. The third pole has a third-pole width greater than a second-pole width. An inductive coil positioned adjacent to the third magnetic layer controllably magnetizes the third magnetic layer. The third magnetic layer is nonuniformly thick such that a thickness of the third pole is less than a thickness of the third magnetic layer at locations in registry with the inductive coil. The magnetic write structure is conveniently fabricated by depositing the magnetic layers and the inductive coil, masking the third magnetic layer other than the third pole, and removing a portion of the thickness of the third pole.Type: ApplicationFiled: June 25, 2003Publication date: December 30, 2004Applicant: Hitachi Global Storage TechnologiesInventors: Wen-Chien D. Hsiao, Hin P.E. Lee, Jyh-Shuey Lo, Yansheng Luo, Samuel W. Yuan
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Reduction of interference pickup in heads for magnetic recording by minimizing parasitic capacitance
Publication number: 20030165034Abstract: Disclosed is a system and a method for reducing high frequency interference pickup by the read element of the magneto-recording head. The reduction is achieved by reducing the parisitic capacitance between certain elements of the magnetic head. In one embodiment, the areas of the pads and leads, including the areas of the leads over the S1 and the areas of the sensor leads, are reduced. A second implementation involves increasing the separation between the pads and leads and the substrate material. Copper studs or vias may be used to connect the contact pads and the underlying layers. A third implementation includes using a low dielectric constant material as a spacer layer between conductors (leads, pads, magnetic shields) and the substrate.Type: ApplicationFiled: March 1, 2002Publication date: September 4, 2003Inventors: Vladimir Nikitin, Michael Paul Salo, Samuel W. Yuan, Robert Langland Smith, Mark Allen Burleson -
Patent number: 6459552Abstract: A thin film magnetic head employs pole tips members which are coplanar in a plane across the write gap to produce a written track whose width is determined by the thickness of the pole tip members. The coplanar write structure may be combined with a multilayer read sensor disposed in the write gap to produce a narrow trackwidth thin film magnetic head having both write and read capabilities.Type: GrantFiled: March 20, 2000Date of Patent: October 1, 2002Inventors: Francis H. Liu, Hua-Ching Tong, Samuel W. Yuan
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Patent number: 6392850Abstract: Magnetic transducers are formed with common magnetic exchange layers capable of providing assertive and complementary signals. The transducers include an assertive transducer portion and a complementary transducer portion. Between the two transducer portions is a common bias portion which comprises an antiferromagnetic layer providing bias fields in different directions to the respective transducer portions. During normal operations, a current is directed into each of the transducer portions. The assertive transducer portion, being magnetically biased in one direction, generates a varying voltage as an assertive version of the electrical signal. The complementary transducer, being magnetically biased in another direction, generates another varying voltage as a complementary version of the electrical signal. In one embodiment, the transducer portions are implemented to operate as an anisotropic MR(AMR) sensor. In a second embodiment, the transducer portions operate as a giant MR(GMR) or spin valve sensor.Type: GrantFiled: October 19, 1998Date of Patent: May 21, 2002Assignee: Read-Rite CorporationInventors: Hua-Ching Tong, Francis H. Liu, Minshen Tan, Robert Earl Rottmayer, Jian-Gang Zhu, Samuel W. Yuan
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Patent number: 6219205Abstract: A magnetic transducer employs a giant magnetoresistive sensor whose sensing surface is separated by a dielectric layer from a magnetically recorded surface carrying recorded data signals to be read back by the transducer. The dielectric layer serves to protect the sensing layer from corrosion, electrostatic discharge from the record surface, mechanical damage from asperities, thermal asperities from heating resulting from close contact between the transducer and the record surface, and damage from exposure during lapping operations. This structure also reduces the readback pulse width and offtrack assymmetry, and improves servo linearity, thereby increasing recording density. The reduced signal amplitude is compensated for by the use of a giant magnetoresistive transducer with an intrinsically large output. The use of the recessed transducer reduces saturation of the transducer due to the record medium flux at reduced signal amplitudes, thereby increasing readback efficiency.Type: GrantFiled: October 10, 1995Date of Patent: April 17, 2001Assignee: Read-Rite CorporationInventors: Samuel W. Yuan, Robert Earl Rottmayer
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Patent number: 6073338Abstract: A method of manufacturing a thin film magnetic head which employs pole tips members which are coplanar in a plane across the write gap to produce a written track whose width is determined by the thickness of the pole tip members. The coplanar write structure may be-combined with a multilayer read sensor disposed in the write gap to produce a narrow trackwidth thin film magnetic head having both write and read capabilities.Type: GrantFiled: August 19, 1997Date of Patent: June 13, 2000Assignee: Read-Rite CorporationInventors: Francis H. Liu, Hua-Ching Tong, Samuel W. Yuan
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Patent number: 5923505Abstract: A magnetoresistive (MR) read sensor fabricated on a substrate comprises an MR layer of magnetoresistive material, a soft adjacent layer (SAL) of soft magnetic material, and a manganese-based metallic antiferromagnetic (AFM) layer between the MR layer and the SAL layer. The AFM layer is in direct contact with the SAL layer and is separated from the MR layer by a non-magnetic spacer layer. A non-magnetic texturing layer is disposed between the SAL layer and the substrate. This structure exhibits a much larger pinning field than read sensors using oxide-based antiferromagnets.Type: GrantFiled: March 17, 1997Date of Patent: July 13, 1999Assignee: Read-Rite CorporationInventors: Derek Jan Kroes, Marcos M. Lederman, Samuel W. Yuan
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Patent number: 5883763Abstract: A compact read/write head having a biased giant magnetoresistive sensor. Permanent magnet films are placed adjacent to the giant magnetoresistive sensor operating in the current-perpendicular-to the-plane (Cpp) mode and spaced with respect to the sensor by conducting films. These permanent magnet films provide a magnetic bias. The bias field is substantial and fairly uniform across sensor height. Biasing of the giant magnetoresistive sensor provides distinguishable response to the rising and falling edges of a recorded pulse on an adjacent recording medium, improves the linearity of the response, and helps to reduce noise. This read/write head is much simpler to fabricate and pattern and provides an enhanced uniformity of the bias field throughout the sensor.Type: GrantFiled: August 19, 1997Date of Patent: March 16, 1999Assignees: Read-Rite Corporation, Regents of the University of CaliforniaInventors: Samuel W. Yuan, Robert Earl Rottmayer, Matthew J. Carey
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Patent number: 5859754Abstract: Magnetic transducers are formed with common magnetic exchange layers capable of providing assertive and complementary signals. The transducers include an assertive transducer portion and a complementary transducer portion. Between the two transducer portions is a common bias portion which comprises an antiferromagnetic layer providing bias fields in different directions to the respective transducer portions. During normal operations, a current is directed into each of the transducer portions. The assertive transducer portion, being magnetically biased in one direction, generates a varying voltage as an assertive version of the electrical signal. The complementary transducer, being magnetically biased in another direction, generates another varying voltage as a complementary version of the electrical signal. In one embodiment, the transducer portions are implemented to operate as an anisotropic MR(AMR) sensor. In a second embodiment, the transducer portions operate as a giant MR(GMR) or spin valve sensor.Type: GrantFiled: April 3, 1997Date of Patent: January 12, 1999Assignee: Read-Rite CorporationInventors: Hua-Ching Tong, Francis H. Liu, Minshen Tan, Robert Earl Rottmayer, Jian-Gang Zhu, Samuel W. Yuan
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Patent number: 5818685Abstract: A magnetic thin film head employing giant magnetoresistance (GMR) includes alternating layers of ferromagnetic material and nonmagnetic material coupled by magnetostatic and exchange interactions to produce an antiparallel orientation between the magnetic layers in the absence of an external field. Magnetic biasing is applied by a permanent magnet to the alternating layers to obtain a scissor-like configuration of the adjacent magnetic layers. The magnet is placed in contiguous junction with the multilayered GMR structure edge which is away from the air bearing surface, and is separated from the sensor by a nonmagnetic, nonconductive spacer.Type: GrantFiled: May 5, 1997Date of Patent: October 6, 1998Assignee: Read-Rite CorporationInventors: Pradeep K. Thayamballi, Samuel W. Yuan
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Patent number: 5748413Abstract: A magnetoresistive (MR) read transducer includes an MR sensor element having end regions and a center active region. The end regions are pinned both top and bottom by an exchange coupling antiferromagnetic material. This pinning action causes the end regions to act as permanent magnets having the same remanent magnetic moment M.sub.r as that of the center active region, thereby resulting in suppression of magnetic edge effects in the transducer. A magnetic soft bias layer adjacent to the magnetoresistive sensor element also has its ends pinned by exchange coupling antiferromagnetic material.Type: GrantFiled: June 4, 1996Date of Patent: May 5, 1998Assignee: Read-Rite CorporationInventors: Marcos M. Lederman, Samuel W. Yuan