Patents by Inventor Lien-Chang Wang
Lien-Chang Wang 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: 9520146Abstract: A method of forming a wrapped-around shielded perpendicular magnetic recording writer pole is disclosed. A structure comprising a leading shield layer and an intermediate layer disposed over the leading shield layer is provided, the intermediate layer comprising a pole material and a dielectric material. A trench is formed in the dielectric material. A non-magnetic layer in the trench is removed via an ion beam etching process. A seed layer is deposited in the trench and over the pole material. A magnetic material comprising a side shield layer is deposited on at least a portion of the seed layer.Type: GrantFiled: August 21, 2013Date of Patent: December 13, 2016Assignee: Western Digital (Fremont), LLCInventors: Jinwen Wang, Weimin Si, Jianxin Fang, Ying Hong, Hongzhou Jiang, Ching-Huang Lu, Yan Chen, Donghong Li, Lien-Chang Wang, Lieping Zhong, Tao Pan
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Patent number: 9508363Abstract: A method provides a magnetic transducer having an air-bearing surface (ABS) location. An intermediate layer having a substantially flat bottom surface is provided. A trench is formed in the intermediate layer. The trench is wider in yoke region than in the pole tip region. The trench has a first depth in the yoke region and a second depth less than the first depth in the pole tip region. A portion of the intermediate layer is at the bottom of the trench at the ABS location. A nonmagnetic layer is provided. The nonmagnetic layer fills part of the trench in the pole tip region such that the trench has a third depth less than the second depth at the ABS location. A main pole is provided. The main pole has a leading bevel adjacent to nonmagnetic layer in the portion of the pole tip region of the trench.Type: GrantFiled: June 17, 2014Date of Patent: November 29, 2016Assignee: WESTERN DIGITAL (FREMONT), LLCInventors: Mingjun Yu, Donghong Li, Lien-Chang Wang, Lieping Zhong, Tao Pan
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Publication number: 20150248899Abstract: A method provides a magnetic transducer having an air-bearing surface. The method includes providing a main pole that has a plurality of sidewalls. The step of providing the main pole includes providing a trailing bevel. A side shield after the trailing bevel has been provided.Type: ApplicationFiled: June 9, 2014Publication date: September 3, 2015Inventors: MINGJUN YU, DONGHONG LI, LIEN-CHANG WANG, LIEPING ZHONG, TAO PAN
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Patent number: 9082426Abstract: Methods for manufacturing electronic lapping guides (ELGs) for writer heads that closely track the pole formation of the writer heads are provided. Once such method includes forming an ELG adjacent to a writer head that is subjected to substantially all of the sub-processing actions associated with the pole formation of the writer head, lapping the pole material, measuring a resistance of the ELG during the lapping, comparing the measured resistance with a target resistance, and terminating the lapping based on the comparison of the measured resistance with the target resistance.Type: GrantFiled: December 19, 2012Date of Patent: July 14, 2015Assignee: Western Digital (Fremont), LLCInventors: Yan Chen, Donghong Li, Ronghui Zhou, Lien-Chang Wang, Lily Yao, Ming Jiang
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Patent number: 8988825Abstract: A method and system provide a magnetic transducer having an air-bearing surface (ABS) location. An intermediate is provided. The intermediate layer includes a first sublayer and a second sublayer in at least a side shield region. The first sublayer has a first sublayer top. The second sublayer is on the first sublayer top in the shield region. A trench is formed in the intermediate layer using at least one etch. A main pole is provided in the trench. The main pole has a bottom and a top wider than the bottom. The first sublayer top is between the top and the bottom of the main pole. At least a portion of the second sublayer is removed in the shield region. At least one half side shield is provided. A bottom of the at least one half side shield being between the top and the bottom of the main pole.Type: GrantFiled: May 16, 2014Date of Patent: March 24, 2015Assignee: Western Digital (Fremont, LLCInventors: Jinqiu Zhang, Lien-Chang Wang, Xiaoyu Yang, Feng Liu, Ming Jiang
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Patent number: 8982508Abstract: A magnetic transducer having an air-bearing surface is described. The magnetic transducer includes a nonmagnetic layer on an underlayer, a pole having a plurality of sidewalls, a gap layer on the sidewalls, a seed layer and at least one side shield. The nonmagnetic layer has an aperture therein. The aperture is free of magnetic inclusions at the ABS. The pole is on the underlayer and within the aperture. The seed layer is for the side shield(s) and resides on the gap layer, a portion of the underlayer and a portion of the nonmagnetic layer. The side shield(s) residing on the seed layer and in the aperture. The side shield(s) are free of undercuts at the ABS.Type: GrantFiled: March 27, 2013Date of Patent: March 17, 2015Assignee: Western Digital (Fremont), LLCInventors: Yan Chen, Donghong Li, Lien-Chang Wang
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Patent number: 8980109Abstract: A method fabricates a magnetic transducer having a nonmagnetic layer and an ABS location corresponding to an ABS. A pole trench is provided in the nonmagnetic layer. The pole trench has a pole tip region and a yoke region. At least one pole material is provided. The pole material(s) have an external protrusion that is above and external to the pole trench. A hard mask that covers at least the external protrusion is provided. A portion of the nonmagnetic layer adjacent to the pole trench is removed to form a side shield trench. At least one side shield material is provided. A portion of the side shield material(s) are adjacent to the hard mask and fill at least a portion of the side shield trench. The side shield material(s) and the pole material(s) are planarized to form at least one side shield and a main pole.Type: GrantFiled: December 11, 2012Date of Patent: March 17, 2015Assignee: Western Digital (Fremont), LLCInventors: Ronghui Zhou, Lily Yao, Ming Jiang, Lien-Chang Wang
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Patent number: 8970988Abstract: A method and system provide a magnetic transducer having an air-bearing surface (ABS) and at least two read sensors. The magnetic transducer also includes a first read shield, a first read sensor, a middle shield, a second read sensor, a second read shield, a first electric gap and a second electric gap. The first read sensor is in a down track direction from the first read shield. The middle shield is in a down track direction from the first read sensor. The middle shield is between the first read sensor and the second read sensor. A first portion of the first electric gap is in a direction opposite to the down track direction from the first read sensor. The first read sensor and the second read sensor are between the first electric gap and the second electric gap in a cross-track direction.Type: GrantFiled: April 15, 2014Date of Patent: March 3, 2015Assignee: Western Digital (Fremont), LLCInventors: Shaoping Li, Gerardo A. Bertero, Changhe Shang, Ge Yi, Steven C. Rudy, Guolun Hao, Qunwen Leng, Shihai He, Yingbo Zhang, Ming Mao, Lien-Chang Wang
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Patent number: 8914969Abstract: A method fabricates a magnetic transducer. A sacrificial leading shield is provided on an etch stop layer. A nonmagnetic layer is provided on the sacrificial leading shield. A pole trench is formed in the nonmagnetic layer and on the sacrificial leading shield. A pole is formed. The pole has a bottom and a top wider than the bottom in a pole tip region. Part of the pole in the pole tip region is in the pole trench and at the ABS location. The sacrificial leading shield and part of the nonmagnetic layer adjacent to the pole are removed. An air bridge thus resides in place of the sacrificial leading shield between the portion of the pole and the etch stop layer. As least one shield layer is provided. The at least one shield layer substantially fills the air bridge and form a monolithic shield including a leading and side shields.Type: GrantFiled: December 17, 2012Date of Patent: December 23, 2014Assignee: Western Digital (Fremont), LLCInventors: Xiaotian Zhou, Hongzhou Jiang, Donghong Li, Lien-Chang Wang, Ching-Huang Lu, Wencheng Su, Lieping Zhong, Tao Pan
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Patent number: 8546151Abstract: Disclosed is a method for manufacturing a magnetic storage device comprising a TMR element, which comprises a step for forming an insulting film on an interlayer insulating film provided with a wiring layer, an opening formation step for forming an opening in the insulating film so that the wiring layer is exposed therefrom, a metal layer formation step for forming a metal layer on the insulating layer so that the opening is filled therewith, a CMP step for polishing and removing the metal layer on the insulating layer by a CMP method and forming the metal layer remaining in the opening into a lower electrode, and a step for forming a TMR element on the lower electrode.Type: GrantFiled: February 25, 2008Date of Patent: October 1, 2013Assignee: Renesas Electronics CorporationInventors: Haruo Furuta, Shuichi Ueno, Ryoji Matsuda, Tatsuya Fukumura, Takeharu Kuroiwa, Lien-Chang Wang, Eugene Chen, Yiming Huai
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Patent number: 8533937Abstract: A method or forming a wrapped-around shielded perpendicular magnetic recording writer pole is disclosed. A structure comprising a leading shield layer and an intermediate layer disposed over the leading shield layer is provided, the intermediate layer comprising a pole material and a dielectric material. A trench is formed in the dielectric material. A non-magnetic layer in the trench is removed via an ion beam etching process. A seed layer is deposited in the trench and over the pole material. A magnetic material comprising a side shield layer is deposited on at least a portion of the seed layer.Type: GrantFiled: October 18, 2011Date of Patent: September 17, 2013Assignee: Western Digital (Fremont), LLCInventors: Jinwen Wang, Weimin Si, Jianxin Fang, Ying Hong, Hongzhou Jiang, Ching-Huang Lu, Yan Chen, Donghong Li, Lien-Chang Wang, Lieping Zhong, Tao Pan
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Patent number: 8419954Abstract: A method for fabricating a side shield for a magnetic transducer is described. The transducer has a nonmagnetic layer, a pole, a gap layer between the pole sidewalls and the nonmagnetic layer, and a hard mask having a hard mask aperture. A removal mask having a removal aperture exposing part of the pole and hard mask aperture is provided. The removal mask covers part of the hard mask aperture and the part of the hard mask. A trench in the nonmagnetic layer is formed by removing part of the nonmagnetic layer. A seed layer is deposited. A deposition mask having a deposition aperture therein is provided. The deposition aperture exposes part of the trench and part of the nonmagnetic layer. Side shield material(s) are deposited. Part of the side shield material(s) external to the deposition trench are removed. A remaining portion of the side shield material forms the side shield.Type: GrantFiled: October 31, 2011Date of Patent: April 16, 2013Assignee: Western Digital (Fremont), LLCInventors: Yan Chen, Donghong Li, Lien-Chang Wang
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Patent number: 8104166Abstract: A method is provided for fabricating a read element with leads that overlay a top surface of a sensor of the read element. The method includes forming a mask over a sensor layer, then using the mask to define the sensor from the sensor layer. The mask is then narrowed and a lead layer is formed that overlays both ends of the top surface of the sensor without covering a center portion of the top surface.Type: GrantFiled: December 19, 2003Date of Patent: January 31, 2012Assignee: Western Digital (Fremont), LLCInventors: Jinqiu Zhang, Ming Zhao, Mohamad T. Krounbi, Henry Yuan, Lien-Chang Wang
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Publication number: 20100264501Abstract: Disclosed is a method for manufacturing a magnetic storage device comprising a TMR element, which comprises a step for forming an insulting film on an interlayer insulating film provided with a wiring layer, an opening formation step for forming an opening in the insulating film so that the wiring layer is exposed therefrom, a metal layer formation step for forming a metal layer on the insulating layer so that the opening is filled therewith, a CMP step for polishing and removing the metal layer on the insulating layer by a CMP method and forming the metal layer remaining in the opening into a lower electrode, and a step for forming a TMR element on the lower electrode.Type: ApplicationFiled: February 25, 2008Publication date: October 21, 2010Inventors: Haruo Furuta, Shuichi Ueno, Ryoji Matsuda, Tatsuta Fukumura, Takeharu Kuroiwa, Lien-Chang Wang, Eugene Chen, Yiming Huai
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Patent number: 7800937Abstract: A method for writing a memory cell of a magnetoresistive random access memory (MRAM) device includes, sequentially, providing a first magnetic field in a first direction, providing a second magnetic field in a second direction substantially perpendicular to the first direction, turning off the first magnetic field, providing a third magnetic field in a third direction opposite to the first direction, turning off the second magnetic field, and turning off the third magnetic field. A method for switching magnetic moments in an MRAM memory cell includes providing a magnetic field in a direction forming a blunt angle with a direction of a bias magnetic field. A method for reading an MRAM device includes partially switching magnetic moments in a reference memory cell to generate a reference current; measuring a read current through a memory cell to be read; and comparing the read current with the reference current.Type: GrantFiled: July 18, 2008Date of Patent: September 21, 2010Assignee: Industrial Technology Research InstituteInventors: Chien-Chung Hung, Ming-Jer Kao, Yuan-Jen Lee, Lien-Chang Wang
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Patent number: 7738287Abstract: A method and system for providing a magnetic memory is disclosed. The method and system include providing a plurality of magnetic storage cells in an array, a plurality of bit lines, and at least one bias structure. Each of the plurality of magnetic storage cells includes at least one magnetic element having an easy axis and being programmable by at least one write current driven through the magnetic element. The plurality of bit lines corresponds to the plurality of magnetic storage cells. The at least one bias structure is magnetically coupled with the at least one magnetic element in each of the plurality of magnetic storage cells. The at least one bias structure provides a bias field in a direction greater than zero degrees and less than one hundred eighty degrees from the easy axis.Type: GrantFiled: March 27, 2007Date of Patent: June 15, 2010Assignee: Grandis, Inc.Inventors: Zhitao Diao, Lien-Chang Wang, Yiming Huai
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Patent number: 7623369Abstract: A method and system for providing a magnetic memory is described. The method and system include providing magnetic memory cells, local and global word lines, bit lines, and source lines. Each magnetic memory cell includes a magnetic element and a selection device connected with the magnetic element. The magnetic element is programed by first and second write currents driven through the magnetic element in first and second directions. The local word lines are connected with the selection device of and have a first resistivity. Each global word line corresponds to a portion of the local word lines and has a resistivity lower than the first resistivity. The bit lines are connected with the magnetic element. The source lines are connected with the selection device. Each source line corresponds to a more than one of the magnetic memory cells and carries the first and second write currents.Type: GrantFiled: February 13, 2008Date of Patent: November 24, 2009Assignees: Grandis, Inc., Renesas Technology Corp.Inventors: Xiao Luo, Eugene Chen, Lien-Chang Wang, Yiming Huai
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Publication number: 20090003043Abstract: A method for writing a memory cell of a magnetoresistive random access memory (MRAM) device includes, sequentially, providing a first magnetic field in a first direction, providing a second magnetic field in a second direction substantially perpendicular to the first direction, turning off the first magnetic field, providing a third magnetic field in a third direction opposite to the first direction, turning off the second magnetic field, and turning off the third magnetic field. A method for switching magnetic moments in an MRAM memory cell includes providing a magnetic field in a direction forming a blunt angle with a direction of a bias magnetic field. A method for reading an MRAM device includes partially switching magnetic moments in a reference memory cell to generate a reference current; measuring a read current through a memory cell to be read; and comparing the read current with the reference current.Type: ApplicationFiled: July 18, 2008Publication date: January 1, 2009Inventors: Chien-Chung Hung, Ming-Jer Kao, Yuan-Jen Lee, Lien-Chang Wang
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Publication number: 20080273380Abstract: A method and system for providing a magnetic memory is disclosed. The method and system include providing a plurality of magnetic storage cells in an array, a plurality of bit lines, and at least one bias structure. Each of the plurality of magnetic storage cells includes at least one magnetic element having an easy axis and being programmable by at least one write current driven through the magnetic element. The plurality of bit lines corresponds to the plurality of magnetic storage cells. The at least one bias structure is magnetically coupled with the at least one magnetic element in each of the plurality of magnetic storage cells. The at least one bias structure provides a bias field in a direction greater than zero degrees and less than one hundred eighty degrees from the easy axis.Type: ApplicationFiled: March 27, 2007Publication date: November 6, 2008Applicant: GRANDISInventors: Zhitao Diao, Lien-Chang Wang, Yiming Huai
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Publication number: 20080239800Abstract: A magnetic memory array. A first bit line provides a first writing magnetic field to a magnetic memory cell. A second bit line provides a second writing magnetic field to a reference magnetic memory cell. A word line provides a third writing magnetic field to the magnetic memory cell and a fourth writing magnetic field to the reference magnetic memory cell. The third writing magnetic field exceeds the fourth writing magnetic field.Type: ApplicationFiled: June 6, 2008Publication date: October 2, 2008Inventors: Chi-Ming Chen, Chien-Chung Hung, Young-Shying Chen, Lien-Chang Wang