Patents Assigned to Headway Technologies, Inc.
  • Patent number: 9391265
    Abstract: A MTJ for a domain wall motion device includes a thin seed layer that enhances perpendicular magnetic anisotropy (PMA) in an overlying laminated layer with a (Co/Ni)n composition or the like where n is from 2 to 30. The seed layer is preferably NiCr, NiFeCr, Hf, or a composite thereof with a thickness from 10 to 100 Angstroms. Furthermore, a magnetic layer such as CoFeB may be formed between the laminated layer and a tunnel barrier layer to serve as a transitional layer between a (111) laminate and (100) MgO tunnel barrier. There may be a Ta insertion layer between the CoFeB layer and laminated layer to promote (100) crystallization in the CoFeB layer. The laminated layer may be used as a reference layer, dipole layer, or free layer in a MTJ. Annealing between 300° C. and 400° C. may be used to further enhance PMA in the laminated layer.
    Type: Grant
    Filed: October 31, 2014
    Date of Patent: July 12, 2016
    Assignee: Headway Technologies, Inc.
    Inventors: Guenole Jan, Witold Kula, Ru Ying Tong, Yu Jen Wang
  • Patent number: 9378762
    Abstract: A thermally-assisted magnetic recording head includes a waveguide, a first plasmon generator, and a second plasmon generator. The waveguide includes a core and a cladding. The first plasmon generator is located on the leading side of the core. The second plasmon generator is located on the trailing side of the core. The cladding includes a first interposition section and a second interposition section, the first interposition section being interposed between the core and the first plasmon generator, the second interposition section being interposed between the core and the second plasmon generator.
    Type: Grant
    Filed: June 25, 2015
    Date of Patent: June 28, 2016
    Assignee: HEADWAY TECHNOLOGIES, INC.
    Inventors: Yoshitaka Sasaki, Hiroyuki Ito, Shigeki Tanemura, Hironori Araki, Kazuki Sato, Seiichiro Tomita
  • Patent number: 9373778
    Abstract: A MTJ for a spintronic device includes a thin seed layer that enhances perpendicular magnetic anisotropy (PMA) in an overlying laminated layer with a (Co/Ni)n composition or the like where n is from 2 to 30. The seed layer is preferably NiCr, NiFeCr, Hf, or a composite thereof with a thickness from 10 to 100 Angstroms. Furthermore, a magnetic layer such as CoFeB may be formed between the laminated layer and a tunnel barrier layer to serve as a transitional layer between a (111) laminate and (100) MgO tunnel barrier. There may be a Ta insertion layer between the CoFeB layer and laminated layer to promote (100) crystallization in the CoFeB layer. The laminated layer may be used as a dipole layer in a MTJ. Annealing between 300° C. and 400° C. may be used to further enhance PMA in the laminated layer.
    Type: Grant
    Filed: October 31, 2014
    Date of Patent: June 21, 2016
    Assignee: Headway Technologies, Inc.
    Inventors: Guenole Jan, Witold Kula, Ru Ying Tong, Yu Jen Wang
  • Patent number: 9372241
    Abstract: A method by which portions of a wafer level fabrication can be selectively heated by forming plasmon generating layers of specific size, shape, orientation and material on the fabrication and then illuminating the formation with electromagnetic radiation of such wavelength and polarization as will optimally be absorbed by the plasmon generating layers so as to generate plasmons therein. The generated plasmons thereupon produce thermal energy which is transferred to portions of the fabrication with which the plasmon generation layer has thermal contact. This method is particularly advantageous for producing multiple anneals and different magnetic pinning directions for the anti-ferromagnetic pinning layer in each of an array of GMR or TMR devices. In that process, the anti-ferromagnetic layer must be raised above its Curie temperature at which point it loses its anti-ferromagnetic properties and can have a magnetization imposed by application of an external magnetic field.
    Type: Grant
    Filed: November 6, 2009
    Date of Patent: June 21, 2016
    Assignee: Headway Technologies, Inc.
    Inventors: Yuchen Zhou, Xuhui Jin, Grace Gorman
  • Patent number: 9373777
    Abstract: A MTJ for a spintronic device includes a thin seed layer that enhances perpendicular magnetic anisotropy (PMA) in an overlying laminated layer with a (Co/Ni)n composition or the like where n is from 2 to 30. The seed layer is preferably NiCr, NiFeCr, Hf, or a composite thereof with a thickness from 10 to 100 Angstroms. Furthermore, a magnetic layer such as CoFeB may be formed between the laminated layer and a tunnel barrier layer to serve as a transitional layer between a (111) laminate and (100) MgO tunnel barrier. There may be a Ta insertion layer between the CoFeB layer and laminated layer to promote (100) crystallization in the CoFeB layer. The laminated layer may be used as a reference layer in a MTJ. Annealing between 300° C. and 400° C. may be used to further enhance PMA in the laminated layer.
    Type: Grant
    Filed: October 31, 2014
    Date of Patent: June 21, 2016
    Assignee: Headway Technologies, Inc.
    Inventors: Guenole Jan, Witold Kula, Ru Ying Tong, Yu Jen Wang
  • Patent number: 9373780
    Abstract: A MTJ for a spintronic device is disclosed and includes a thin seed layer that enhances perpendicular magnetic anisotropy (PMA) in an overlying laminated layer with a (Co/X)n or (CoX)n composition where n is from 2 to 30, X is one of V, Rh, Ir, Os, Ru, Au, Cr, Mo, Cu, Ti, Re, Mg, or Si, and CoX is a disordered alloy. The seed layer is preferably NiCr, NiFeCr, Hf, or a composite thereof with a thickness from 10 to 100 Angstroms. Furthermore, a magnetic layer such as CoFeB may be formed between the laminated layer and a tunnel barrier layer to serve as a transitional layer between a (111) laminate and (100) MgO tunnel barrier. The laminated layer may be used as a reference layer, dipole layer, or free layer in a MTJ. Annealing between 300° C. and 400° C. may be used to further enhance PMA in the laminated layer.
    Type: Grant
    Filed: July 31, 2013
    Date of Patent: June 21, 2016
    Assignee: Headway Technologies, Inc.
    Inventors: Guenole Jan, Ru-Ying Tong, Yu-Jen Wang
  • Patent number: 9361923
    Abstract: A shield structure for a PMR writer is disclosed and features a first trailing shield on a write gap, and a second (PP3) trailing shield on the first trailing shield and magnetically connected to the main pole layer. From a top-down view along the down-track direction, the PP3 trailing shield has various shapes to provide shape anisotropy such that following hard magnet or reverse magnet initialization, PP3 trailing shield magnetic orientation has a stable three domain configuration thereby minimizing skip track erasure (STE) or improving area density capability (ADC). At least one sloped side is introduced that forms an angle >90 degrees with the PP3 trailing shield backside. In other embodiments, a thinner leading shield may be used to improve STE. The PP3 trailing shield may have a dome shape or a planar shape from a down-track cross-sectional view.
    Type: Grant
    Filed: April 20, 2015
    Date of Patent: June 7, 2016
    Assignee: Headway Technologies, Inc.
    Inventors: Yue Liu, Moris Dovek, Glen Garfunkel, Yaguang Wei, Yuhui Tang, Po-Kang Wang
  • Patent number: 9361912
    Abstract: A PMR writer is disclosed wherein a hot seed layer (HS) made of a 19-24 kilogauss (kG) magnetic material is formed between a side gap and a 10-16 kG magnetic layer in the side shields, and between a 16-19 kG magnetic layer and the leading gap in the leading shield to improve Hy_grad and Hy_grad_x while maintaining write-ability. The HS is from 10 to 100 nm thick and has a first side facing the write pole with a height of ?0.15 micron, and a second side facing a main pole flared side that may extend to a full side shield height of ?0.5 micron. First and second sides may form a continuous curve or the a double tapered design where first and second sides have different angles with respect to a center plane. The side shield design described herein is especially beneficial for side gaps of 20-60 nm.
    Type: Grant
    Filed: April 20, 2015
    Date of Patent: June 7, 2016
    Assignees: Headway Technologies, Inc., TDK Corporation
    Inventors: Yue Liu, Atsushi Yamaguchi, Yuhui Tang, Jiun-Ting Lee, Yaguang Wei, Xiaomin Liu, Hideyuki Ukita, Moris Dovek, Michitaka Nishiyama
  • Patent number: 9355700
    Abstract: Embodiments are directed to detecting a state of a memory element in a memory device, comprising: applying a pulse of a predetermined magnitude and duration to the memory element to induce a transition in the state of the memory element when a polarity of the pulse is opposite to the state, monitoring, by a device, a signal associated with the memory element to detect a presence or absence of a transition in the signal in an amount greater than a threshold, and determining the state of the memory element based on said monitoring.
    Type: Grant
    Filed: January 29, 2015
    Date of Patent: May 31, 2016
    Assignees: INTERNATIONAL BUSINESS MACHINES CORPORATION, HEADWAY TECHNOLOGIES, INC.
    Inventors: Jonathan Z. Sun, John K. DeBrosse, Po-Kang Wang
  • Patent number: 9349396
    Abstract: A spin transfer oscillator with a seed/SIL/spacer/FGL/capping configuration is disclosed with a composite seed layer made of Ta and a metal layer having a fcc(111) or hcp(001) texture to enhance perpendicular magnetic anisotropy (PMA) in an overlying (A1/A2)X laminated spin injection layer (SIL). Field generation layer (FGL) is made of a high Bs material such FeCo. Alternatively, the STO has a seed/FGL/spacer/SIL/capping configuration. The SIL may include a FeCo layer that is exchanged coupled with the (A1/A2)X laminate (x is 5 to 50) to improve robustness. The FGL may include an (A1/A2)Y laminate (y=5 to 30) exchange coupled with the high Bs layer to enable easier oscillations. A1 may be one of Co, CoFe, or CoFeR where R is a metal, and A2 is one of Ni, NiCo, or NiFe. The STO may be formed between a main pole and trailing shield in a write head.
    Type: Grant
    Filed: February 20, 2015
    Date of Patent: May 24, 2016
    Assignee: Headway Technologies, Inc.
    Inventors: Kunliang Zhang, Min Li, Yuchen Zhou
  • Patent number: 9343132
    Abstract: A write method for a STT-RAM MTJ is disclosed that substantially reduces the bit error rate caused by intermediate domain states generated during write pulses. The method includes a plurality of “n” write periods or pulses and “n?1” domain dissipation periods where a domain dissipation period separates successive write periods. During each pulse, a write current is applied in a first direction across the MTJ and during each domain dissipation period, a second current with a magnitude equal to or less than the read current is applied in an opposite direction across the MTJ. Alternatively, no current is applied during one or more domain dissipation periods. Each domain dissipation period has a duration of 1 to 10 ns that is equal to or greater than the precession period of free layer magnetization in the absence of spin torque transfer current.
    Type: Grant
    Filed: May 22, 2013
    Date of Patent: May 17, 2016
    Assignee: Headway Technologies, Inc.
    Inventors: Yuan-Jen Lee, Po-Kang Wang, Guenole Jan
  • Patent number: 9343463
    Abstract: The structure and method of formation of an integrated CMOS level and active device level that can be a memory device level. The integration includes the formation of a “super-flat” interface between the two levels formed by the patterning of a full complement of active and dummy interconnecting vias using two separate patterning and etch processes. The active vias connect memory devices in the upper device level to connecting pads in the lower CMOS level. The dummy vias may extend up to an etch stop layer formed over the CMOS layer or may be stopped at an intermediate etch stop layer formed within the device level. The dummy vias thereby contact memory devices but do not connect them to active elements in the CMOS level.
    Type: Grant
    Filed: September 29, 2009
    Date of Patent: May 17, 2016
    Assignee: Headway Technologies, Inc.
    Inventors: Tom Zhong, Adam Zhong, Wai-Ming J. Kan, Chyu-Jiuh Torng
  • Patent number: 9337414
    Abstract: A TMR (tunneling magnetoresistive) read sensor is formed in which a portion of the sensor stack containing the ferromagnetic free layer and the tunneling barrier layer is patterned to define a narrow trackwidth, but a synthetic antiferromagnetic pinning/pinned layer is left substantially unpatterned and extends in substantially as-deposited form beyond the lateral edges bounding the patterned portion. The narrow trackwidth of the patterned portion permits high resolution for densely recorded data. The larger pinning/pinned layer significantly improves magnetic stability and reduces thermal noise, while the method of formation eliminates possible ion beam etch (IBE) or reactive ion etch (RIE) damage to the edges of the pinning/pinned layer.
    Type: Grant
    Filed: March 14, 2013
    Date of Patent: May 10, 2016
    Assignee: Headway Technologies, Inc.
    Inventors: Min Li, Ruhang Ding, Cherng Chyi Han, Jianing Zhou, Minghui Yu
  • Patent number: 9336799
    Abstract: A perpendicular magnetic recording (PMR) head is fabricated with main pole and a trailing edge shield antiferromagnetically coupled across a write gap by either having the write gap layer formed as a synthetic antiferromagnetic tri-layer (SAF) or formed as a monolithic layer of antiferromagnetic material. The coupling improves the write performance of the writer by enhancing the perpendicular component of the write field and its gradient. Methods of fabricating the writer are provided.
    Type: Grant
    Filed: October 8, 2013
    Date of Patent: May 10, 2016
    Assignee: Headway Technologies, Inc.
    Inventors: Tai Min, Yuhui Tang, Lijie Guan, Min Li
  • Patent number: 9336798
    Abstract: A main pole includes a main body and a lower protrusion. The lower protrusion is located at a distance from a medium facing surface. The main body includes a front portion and a rear portion. The front portion has a first side surface and a second side surface. The lower protrusion has a third side surface and a fourth side surface. A first side shield has a first sidewall opposed to the first side surface. A second side shield has a second sidewall opposed to the second side surface. A bottom shield includes a receiving section. The receiving section has a third sidewall opposed to the third side surface, and a fourth sidewall opposed to the fourth side surface. The receiving section and the lower protrusion are formed in a self-aligned manner by using the first and second side shields.
    Type: Grant
    Filed: December 11, 2014
    Date of Patent: May 10, 2016
    Assignee: HEADWAY TECHNOLOGIES, INC.
    Inventors: Yoshitaka Sasaki, Kazuki Sato, Hiroyuki Ito, Shigeki Tanemura, Hironori Araki, Yukinori Ikegawa
  • Patent number: 9330690
    Abstract: A method of forming a TAMR (Thermal Assisted Magnetic Recording) write head that uses the energy of optical-laser excited plasmons to locally heat a magnetic recording medium and reduce its coercivity and magnetic anisotropy. The magnetic field of the write head is enhanced by the formation of a leading shield that is formed in a concave geometrical shape and partially surrounds the waveguide portion of the head within the concavity, which allows the distal end of the waveguide to extend to the ABS plane of the write head. This arrangement reduces the gap between the shield and the magnetic pole and does not interfere with the ability of the waveguide to efficiently transfer its optical energy to the plasmon generator and, ultimately, to the surface of the magnetic recording medium.
    Type: Grant
    Filed: December 23, 2013
    Date of Patent: May 3, 2016
    Assignee: Headway Technologies, Inc.
    Inventors: Yiming Wang, Tobias Maletzky, Xuhui Jin, Dayu Zhou, Joe Smyth, Moris Dovek
  • Patent number: 9331271
    Abstract: A STT-RAM MTJ is disclosed with a MgO tunnel barrier formed by natural oxidation and containing an oxygen surfactant layer to form a more uniform MgO layer and lower breakdown distribution percent. A CoFeB/NCC/CoFeB composite free layer with a middle nanocurrent channel layer minimizes Jc0 while enabling thermal stability, write voltage, read voltage, and Hc values that satisfy 64 Mb design requirements. The NCC layer has RM grains in an insulator matrix where R is Co, Fe, or Ni, and M is a metal such as Si or Al. NCC thickness is maintained around the minimum RM grain size to avoid RM granules not having sufficient diameter to bridge the distance between upper and lower CoFeB layers. A second NCC layer and third CoFeB layer may be included in the free layer or a second NCC layer may be inserted below the Ru capping layer.
    Type: Grant
    Filed: December 6, 2013
    Date of Patent: May 3, 2016
    Assignee: Headway Technologies, Inc.
    Inventors: Cheng T. Horng, Ru-Ying Tong, Guangli Liu, Robert Beach, Witold Kula, Tai Min
  • Patent number: 9330702
    Abstract: A thermally-assisted magnetic recording head includes a main pole, a waveguide, a plasmon generator, and a heat sink. The heat sink includes a first metal layer, a second metal layer, and an intermediate layer. The intermediate layer is interposed between the first metal layer and the second metal layer. Each of the first and second metal layers is formed of a metal material. The intermediate layer is formed of a material that is higher in Vickers hardness than the metal material used to form the first metal layer and the metal material used to form the second metal layer.
    Type: Grant
    Filed: September 30, 2013
    Date of Patent: May 3, 2016
    Assignee: HEADWAY TECHNOLOGIES, INC.
    Inventors: Hironori Araki, Yoshitaka Sasaki, Hiroyuki Ito, Shigeki Tanemura, Yukinori Ikegawa
  • Publication number: 20160115612
    Abstract: A thin-film magnetic head includes a coil, a magnetic path forming section, and an insulating film. The magnetic path forming section includes first and second magnetic material portions. The coil includes first and second coil elements located between the first and second magnetic material portions. The insulating film includes an underlying portion located under the first and second coil elements. In a method of manufacturing the thin-film magnetic head, the insulating film is formed to cover the first and second magnetic material portions, and then a seed layer is formed selectively on the underlying portion of the insulating film. The coil is formed by plating using the seed layer.
    Type: Application
    Filed: October 24, 2014
    Publication date: April 28, 2016
    Applicant: HEADWAY TECHNOLOGIES, INC.
    Inventors: Yukinori IKEGAWA, Yoshitaka SASAKI, Hiroyuki ITO, Hironori ARAKI, Seiichiro TOMITA, Hideo MAMIYA
  • Patent number: 9324341
    Abstract: A magnetic head includes a main pole, an expansion member, and a heater. The main pole has an end face located in a medium facing surface. The expansion member is located farther from the medium facing surface than is the main pole and adjacent to the main pole in a direction perpendicular to the medium facing surface. The heater heats the expansion member. The expansion member has a linear expansion coefficient higher than that of the main pole.
    Type: Grant
    Filed: November 18, 2013
    Date of Patent: April 26, 2016
    Assignees: HEADWAY TECHNOLOGIES, INC., SAE MAGNETICS (H.K.) LTD.
    Inventors: Yoshitaka Sasaki, Hiroyuki Ito, Shigeki Tanemura, Kazuki Sato, Tatsuya Shimizu