Patents by Inventor Sining Mao
Sining Mao 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).
-
Patent number: 7724469Abstract: A magnetic writer includes a write element and an oscillation device disposed adjacent to the write element. The first oscillation device includes a first magnetic layer, a second magnetic layer having a magnetization vector including a component perpendicular to a major plane of the first magnetic layer. The first nonmagnetic layer disposed between the first magnetic layer and the second magnetic layer. The first oscillation device generates a high-frequency oscillation field when a current is directed perpendicular to the major plane of the first magnetic layer.Type: GrantFiled: December 6, 2006Date of Patent: May 25, 2010Assignee: Seagate Technology LLCInventors: Kaizhong Gao, Haiwen Xi, Yiming Shi, Sining Mao, Patrick J. Ryan, Song S. Xue, Shaoping Li
-
Publication number: 20100021767Abstract: A method of fabricating a discrete track magnetic recording media. A base layer is provided onto which repeating and alternating magnetic layer and non-magnetic layers are deposited. The thickness of the magnetic layer corresponds to the width of the track of the recording media. A cylindrical rod can be used as the base layer, such that the alternating magnetic and non-magnetic layers spiraling or concentric layers around the rod. The resulting media layer can be cut or sliced into individual magnetic media or used to imprint other media discs with the discrete pattern of the media layer.Type: ApplicationFiled: July 23, 2008Publication date: January 28, 2010Applicant: SEAGATE TECHNOLOGY LLCInventors: Nurul Amin, Sining Mao
-
Patent number: 7589928Abstract: A system includes a magnetic device for writing to and reading from a magnetic medium and a sensor disposed adjacent to the magnetic device and proximate to the magnetic medium. The sensor generates signals related to thermal variations in the sensor caused by changes in a distance between the magnetic device and the magnetic medium.Type: GrantFiled: March 16, 2007Date of Patent: September 15, 2009Assignee: Seagate Technology LLCInventors: Mallika Roy, Kaizhong Gao, Insik Jin, William Bruce Fitzpatrick, Housan S. Dakroub, Sining Mao, Song S. Xue, Jeffrey Howard Lake, Dadi Setiadi
-
Publication number: 20080316631Abstract: A magnetic device includes a write element having a write element tip and a conductive coil that carries current to induce a first field in the write element. A first conductor is proximate a leading edge of the write pole tip for carrying current to generate a second field that augments the first field.Type: ApplicationFiled: June 20, 2007Publication date: December 25, 2008Applicant: Seagate Technology LLCInventors: Kaizhong Gao, Sining Mao, Eric S. Linville, Xuebing Feng, Shaoping Li, Steven Paul Bozeman
-
Publication number: 20080225435Abstract: A writer includes a write element having a tip portion for generating a write field and a conductive assembly that delivers a write assist current through the tip portion to generate a write assist field.Type: ApplicationFiled: March 15, 2007Publication date: September 18, 2008Applicant: Seagate Technology LLCInventors: Chunhong Hou, Shaoping Li, John M. Wolf, Sining Mao
-
Publication number: 20080225584Abstract: The present invention relates to a memory cell including a first reference layer having a first magnetization with a first magnetization direction and a second reference layer having a second magnetization with a second magnetization direction substantially perpendicular to the first magnetization direction. A storage layer is disposed between the first reference layer and second reference layer and has a third magnetization direction about 45° from the first magnetization direction and about 135° from the second magnetization direction when the memory cell is in a first data state, and a fourth magnetization direction opposite the third magnetization direction when the memory cell is in a second data state.Type: ApplicationFiled: March 16, 2007Publication date: September 18, 2008Applicant: Seagate Technology LLCInventors: Kaizhong Gao, Haiwen Xi, Yiming Shi, Song S. Xue, Sining Mao
-
Publication number: 20080225426Abstract: A system includes a magnetic device for writing to and reading from a magnetic medium and a sensor disposed adjacent to the magnetic device and proximate to the magnetic medium. The sensor generates signals related to thermal variations in the sensor caused by changes in a distance between the magnetic device and the magnetic medium.Type: ApplicationFiled: March 16, 2007Publication date: September 18, 2008Applicant: Seagate Technology LLCInventors: Mallika Roy, Kaizhong Gao, Insik Jin, William Bruce Fitzpatrick, Housan S. Dakroub, Sining Mao, Song S. Xue, Jeffrey Howard Lake, Dadi Setiadi
-
Publication number: 20080165452Abstract: A magnetic writer includes a first write element and a second write element. The first write element produces a first field when a first current is passed through a first coil. The second write element, which is disposed relative to the first write element, produces a second field when a second current is passed through a second coil such that the second field at least partially opposes the first field.Type: ApplicationFiled: January 9, 2007Publication date: July 10, 2008Applicant: Seagate Technology LLCInventors: Steven Paul Bozeman, Olle Gunnar Heinonen, Sining Mao
-
Publication number: 20080137224Abstract: A magnetic writer includes a write element and an oscillation device disposed adjacent to the write element. The first oscillation device includes a first magnetic layer, a second magnetic layer having a magnetization vector including a component perpendicular to a major plane of the first magnetic layer. The first nonmagnetic layer disposed between the first magnetic layer and the second magnetic layer. The first oscillation device generates a high-frequency oscillation field when a current is directed perpendicular to the major plane of the first magnetic layer.Type: ApplicationFiled: December 6, 2006Publication date: June 12, 2008Applicant: Seagate Technology LLCInventors: Kaizhong Gao, Haiwen Xi, Yiming Shi, Sining Mao, Patrick J. Ryan, Song S. Xue, Shaoping Li
-
Patent number: 7177122Abstract: A biasing system for a tri-layer reader stack magnetoresistive sensor is disclosed. The tri-layer reader stack includes a first ferromagnetic free layer, a second ferromagnetic free layer, and a magnetoresistive layer between the first and second ferromagnetic free layers. The free layers are positioned in the tri-layer reader stack such that quiescent state magnetizations of the free layers are antiparallel. A biasing layer is positioned with regard to the tri-layer reader stack, typically separated from the tri-layer reader stack by a nonmagnetic spacer layer. A biasing means is positioned such that a magnetization of the biasing layer is perpendicular to the quiescent state magnetizations of the free layers. This biasing results in the free layers having biased magnetizations directed substantially orthogonal with respect to each other.Type: GrantFiled: October 27, 2003Date of Patent: February 13, 2007Assignee: Seagate Technology LLCInventors: Chunhong Hou, Sining Mao, Eric S. Linville, Olle Heinonen, Xuefei Tang, Qing He, Eric W. Singleton, Song S. Xue
-
Patent number: 7151654Abstract: The sensor of the present invention is a tunneling magnetoresistive read sensor that includes first and second electrodes, and a stack positioned between the electrodes. The stack includes at least one sense layer and a tunnel barrier. A shunt member is operatively coupled to the electrodes in parallel with the stack. The shunt member diverts current flowing from the first electrode to the second electrode when the sensor is operational so that current simultaneously flows through the stack and the shunt member to reduce the effective resistance of the sensor.Type: GrantFiled: November 19, 2002Date of Patent: December 19, 2006Assignee: Seagate Technology LLCInventors: Sining Mao, Janusz Josef Nowak, Eric Shane Linville, Horng-Shiong Shawn Chen, Song S. Xue
-
Patent number: 7064934Abstract: A magnetoresistive (MR) sensor having reduced operating temperature is disclosed. The MR sensor, which includes an MR stack having a magnetoresistive layer, is configured to operate in a current-perpendicular-to-plane (CPP) mode wherein a sense current flows substantially perpendicular to a longitudinal plane of the magnetoresistive layer. The MR sensor further includes a thermal sink layer positioned with respect to the MR stack to reduce an operating temperature of the magnetoresistive sensor. The thermal sink layer is made of a material having high thermal conductivity, and is preferably separated from the MR stack by a metallic cap or seed layer.Type: GrantFiled: June 12, 2003Date of Patent: June 20, 2006Assignee: Seagate Technology LLCInventors: Sining Mao, William P. Vavra, Eric S. Linville
-
Patent number: 7057865Abstract: A magnetic sensor including a tunneling magnetoresistive stack with a synthetic antiferromagnet (SAF) free layer.Type: GrantFiled: August 9, 2001Date of Patent: June 6, 2006Assignee: Seagate Technology LLCInventors: Sining Mao, Janusz J. Nowak, Eric S. Linville, Jian Chen
-
Patent number: 7035062Abstract: The present invention provides a tunneling magneto-resistive read sensor structure that improves sensitivity and linear density of the sensor structure. The sensor includes first and second electrodes and a stack positioned between the electrodes. The stack includes first and second free layers with magnetization orientations that are biased relative to each other. A tunneling barrier (insulating layer) or non-magnetic metal spacer is positioned between the first and second free layers. A sense current is passed between the first and second free layers of the stack. The amount of current passing through the first and second free layer changes based upon the orientation of the first and second free layers relative to each other.Type: GrantFiled: November 22, 2002Date of Patent: April 25, 2006Assignee: Seagate Technology LLCInventors: Sining Mao, Eric Shane Linville, Zheng Gao, Brian William Karr, Janusz Jozef Nowak, Olle Gunnar Heinonen
-
Patent number: 7016160Abstract: A differential read head comprises one tri-layer reader or a plurality of tri-layer readers operating in a current perpendicular to plane (CPP) mode. The tri-layer readers each comprise a first free layer, a second free layer, and a nonmagnetic layer positioned therebetween. A nonmagnetic spacer is positioned between the plurality of tri-layer readers for electrically connecting the plurality of tri-layer readers in series such that a single CPP sense current representing a differential signal flows serially through the read head. With a single tri-layer reader, the free layers are spaced by a width substantially similar to the transition width of the magnetic medium.Type: GrantFiled: November 18, 2003Date of Patent: March 21, 2006Assignee: Seagate Technology LLCInventors: Sining Mao, Eric S. Linville, Nurul Amin, Johannes Van Ek, Olle G. Heinonen
-
Publication number: 20050105219Abstract: A differential read head comprises one tri-layer reader or a plurality of tri-layer readers operating in a current perpendicular to plane (CPP) mode. The tri-layer readers each comprise a first free layer, a second free layer, and a nonmagnetic layer positioned therebetween. A nonmagnetic spacer means is positioned between the plurality of tri-layer readers for electrically connecting the plurality of tri-layer readers in series such that a single CPP sense current representing a differential signal flows serially through the read head. With a single tri-layer reader, the free layers are spaced by a width substantially similar to the transition width of the magnetic medium.Type: ApplicationFiled: November 18, 2003Publication date: May 19, 2005Applicant: Seagate Technology LLCInventors: Sining Mao, Eric Linville, Nurul Amin, Johannes Van Ek, Olle Heinonen
-
Publication number: 20050088789Abstract: A biasing system for a tri-layer reader stack magnetoresistive sensor is disclosed. The tri-layer reader stack includes a first ferromagnetic free layer, a second ferromagnetic free layer, and a magnetoresistive layer between the first and second ferromagnetic free layers. The free layers are positioned in the tri-layer reader stack such that quiescent state magnetizations of the free layers are antiparallel. A biasing layer is positioned with regard to the tri-layer reader stack, typically separated from the tri-layer reader stack by a nonmagnetic spacer layer. A biasing means is positioned such that a magnetization of the biasing layer is perpendicular to the quiescent state magnetizations of the free layers. This biasing results in the free layers having biased magnetizations directed substantially orthogonal with respect to each other.Type: ApplicationFiled: October 27, 2003Publication date: April 28, 2005Applicant: Seagate Technology LLCInventors: Chunhong Hou, Sining Mao, Eric Linville, Olle Heinonen, Xuefei Tang, Qing He, Eric Singleton, Song Xue
-
Publication number: 20040252414Abstract: A magnetoresistive (MR) sensor having reduced operating temperature is disclosed. The MR sensor, which includes an MR stack having a magnetoresistive layer, is configured to operate in a current-perpendicular-to-plane (CPP) mode wherein a sense current flows substantially perpendicular to a longitudinal plane of the magnetoresistive layer. The MR sensor further includes a thermal sink layer positioned with respect to the MR stack to reduce an operating temperature of the magnetoresistive sensor. The thermal sink layer is made of a material having high thermal conductivity, and is preferably separated from the MR stack by a metallic cap or seed layer.Type: ApplicationFiled: June 12, 2003Publication date: December 16, 2004Applicant: Seagate Technology LLCInventors: Sining Mao, William P. Vavra, Eric S. Linville
-
Patent number: 6795280Abstract: A method and apparatus for a recording head using a spin-dependent tunneling (SDT) junction. The SDT junction utilizes an aluminum oxide tunnel barrier. The tunnel barrier can be formed to a thickness comparable with a typical Cu spacer layer on a spin valve. With the SDT junction, current is applied perpendicular to the plane of the film. The SDT junctions can have high magneto-resistance up to 40%. The magnetoresistive qualities of a head design incorporating the SDT junction are not directly related to head resistance, head geometry, bias current and film thickness. The method can include forming a spin tunnel barrier by fashioning a stack into a bottom electrode, defining a junction, depositing a layer of insulator, performing a photoprocess, depositing an upper electrode layer and lifting off the top electrode layer to define the electrode. The stack can include a pinned layer, a barrier layer and a free layer. The pinned layer can include NiFe. The barrier layer can include AlOx.Type: GrantFiled: November 17, 1999Date of Patent: September 21, 2004Assignee: Seagate Technology LLCInventors: Dian Song, Nurul Amin, Sining Mao
-
Patent number: 6791806Abstract: A tunneling magnetoresistive stack configured to operate in a current-perpendicular-to-plane mode has a plurality of layers including a barrier layer. The TMR stack has a plurality of layers including a barrier layer, wherein the barrier layer is comprised of an insulating material selected from a group consisting of HfO, HfAlO, ZrO, TiO, TaO or NdO. The TMR stack exhibits a low resistance-area (RA) product, a stable magnetoresistive (MR) ratio, a lower RA product, a higher breakdown voltage of the TMR stack and enhanced thermal stability.Type: GrantFiled: August 9, 2002Date of Patent: September 14, 2004Assignee: Seagate Technology LLCInventors: Zheng Gao, Sining Mao, Khoung Tran, Janusz Nowak, Jian Chen