Patents Assigned to SAE Magnetics (HK)
  • Patent number: 8009387
    Abstract: A method for forming a protective bilayer on a magnetic read/write head or magnetic disk. The bilayer is formed as an adhesion enhancing underlayer and a protective diamond-like carbon (DLC) overlayer. The underlayer is formed of an aluminum or alloyed aluminum oxynitride, having the general formula AlOxNy or MezAlOxNy where Mez symbolizes Tiz, Siz or Crz and where x, y and z can be varied within the formation process. By adjusting the values of x and y the adhesion underlayer contributes to such qualities of the protective bilayer as stress compensation, chemical and mechanical stability and low electrical conductivity. Various methods of forming the underlayer are provided, including reactive ion sputtering, plasma assisted chemical vapor deposition, pulsed laser deposition and plasma immersion ion implantation.
    Type: Grant
    Filed: August 2, 2010
    Date of Patent: August 30, 2011
    Assignee: SAE Magnetics (HK) Ltd.
    Inventors: Shide Cheng, Zhu Feng, Ellis T. Cha
  • Patent number: 8000061
    Abstract: Gimbal designs are provided that minimize adverse dynamic performance of a HDD suspension, particularly subsequent to head-disk-interface (HDI) interactions. The improvement of operational performance can be seen in graphical representations of the vibrational modes of a gimbal mounted slider subsequent to such HDI interactions. Each gimbal design includes a ramp limiter formed as two separated arms connected by one or two transverse bars and a routing of conducting traces that relieves stress and minimally contacts these bars.
    Type: Grant
    Filed: March 5, 2010
    Date of Patent: August 16, 2011
    Assignee: SAE Magnetics (HK) Ltd.
    Inventors: Qinghua Zeng, Chao-Hui Yang, Yen Fu, Ellis Cha
  • Patent number: 7978436
    Abstract: A method and apparatus for improving flying height stability in a small form factor hard disk drive that typically moves at lower speeds is achieved by a slider having an ABS with an air channel and pocket. The air channel and pocket are configured to increase the amount of aerodynamic lift provided by normally smaller amounts of intake air at the inner diameter of the rotating disk and, thereby, to achieve a desired flying height profile.
    Type: Grant
    Filed: June 5, 2007
    Date of Patent: July 12, 2011
    Assignee: SAE Magnetics (HK) Ltd.
    Inventors: Ellis T. Cha, Zhu Feng, Xinjiang Shen, Sindy Yeung
  • Patent number: 7969685
    Abstract: A DFH (Dynamic Flying Height) type slider ABS design has a stable flying height and a DFH efficiency that is uniform across the entire disk surface. These properties are a result of embedding the read/write head and heater in a trapezoidally bridged micro-pad having a very small surface area. The micro-pad is surrounded by a wing-like structure that projects from a central rail in the ABS and the micro pad is connected to an inner edge of that structure by a bridge having a trapezoidal shape. The trapezoidal shape responds effectively to variations in air flow direction and pressure point as the slider moves across the disk surface and, as a result, provides the uniform DFH efficiency. At the same time, the projecting wings and adjacent topology help to direct the airflow around the micro-pad and provide the stable flying height.
    Type: Grant
    Filed: August 13, 2008
    Date of Patent: June 28, 2011
    Assignee: SAE Magnetics (HK) Ltd.
    Inventors: Xinjiang Shen, Zhu Feng, Ellis Cha, Robert Chu
  • Patent number: 7961433
    Abstract: A slider is formed with an ABS topography that eliminates the accumulation of lubricant swept from the surface of a rotating disk in an operating HDD. The topography includes air channeling grooves in which are formed backflow blocking elements that prevent the formation airflow patterns that would cause lubricant to be aspirated into the ABS topography of the slider and that create airflow patterns that sweep lubricant away from the ABS of the slider. The topography is first tested to make sure that the slider has the proper flying height and aerodynamic stability, then the backflow blocking elements are added to control the airflow, while maintaining the desired flying height and stability.
    Type: Grant
    Filed: February 29, 2008
    Date of Patent: June 14, 2011
    Assignee: SAE Magnetics (HK) Ltd.
    Inventors: Guoqiang Zheng, Shoji Toyoda, Ellis Cha, Zhu Feng, Collins Lee
  • Patent number: 7957104
    Abstract: A flexure with improved temperature sensitivity is disclosed. An embodiment of the present invention includes a bi-layered flexure that raises or lowers a read/write element a distance that is approximately equal to the distance of protrusion and retraction at varying temperatures.
    Type: Grant
    Filed: March 27, 2007
    Date of Patent: June 7, 2011
    Assignee: SAE Magnetics (HK) Ltd.
    Inventors: Yen Fu, Ellis T. Cha, Chao-Hui Yang
  • Patent number: 7907368
    Abstract: In a balanced head gimbal assembly for improved seeking performance, a slider having a magnetic head with a set of read elements to read data and a set of write elements to write data, an air-bearing surface, and a non-air-bearing surface is coupled to a suspension. The suspension includes a loadbeam, a flexure, and a balancing weight. The loadbeam is coupled to an actuator arm. The flexure, coupled to the loadbeam, has a window through which a dimple, coupled to the loadbeam, contacts a dimple contact point. The balancing weight, coupled to the flexure, has a configuration which permits alignment of a center of mass of the head gimbal assembly with the dimple contact point.
    Type: Grant
    Filed: March 26, 2007
    Date of Patent: March 15, 2011
    Assignee: SAE Magnetics (HK) Ltd.
    Inventors: Qinghua Zeng, Yen Fu, Li-Yan Zhu, Chao-Hui Yang, Ellis T. Cha
  • Patent number: 7894162
    Abstract: A slider mounted read/write head is protected from thermal asperities due to head-disk interactions by a ridge formed along an interfacial plane that extends above the ABS plane of the slider. The ridge is formed as part of a lapping process that is directed from the read/write head towards the slider substrate and uses an abrasive slurry to which may be added a strong base such as KOH. The height of the ridge is less than approximately 2 nm.
    Type: Grant
    Filed: April 16, 2007
    Date of Patent: February 22, 2011
    Assignee: SAE Magnetics (HK) Ltd.
    Inventors: Niraj Mahdev, Kasumaza Yasuda, Ellis Cha
  • Patent number: 7885040
    Abstract: An apparatus with a head gimbal assembly designed to reduce movement and rotation of components of the head gimbal assembly structure is disclosed. One embodiment head gimbal assembly may comprise a flexure including a ramp limiter, a suspension assembly further comprising a suspension tongue, a slider further comprising a magnetic head; and a load beam further comprising a lift tab; and a ramp further comprising a step to engage and support the ramp limiter and support and constrain the movement of the slider. In certain embodiments, the flexure may further comprise a flexure rail located at its end to reduce movement and rotation of the suspension tongue.
    Type: Grant
    Filed: July 6, 2007
    Date of Patent: February 8, 2011
    Assignee: SAE Magnetics (HK) Ltd.
    Inventors: Chao-Hui Yang, Qinghua Zeng, Yen Fu, Ellis T. Cha
  • Patent number: 7836579
    Abstract: A simple method is provided for protecting slider mounted read/write transducers from electrostatic discharge damage during the manufacture of disk drives. The method involves placing a ball of conducting thermoplastic resin, such as a gold or silver epoxy, between the terminal pads of the transducer and using the ball to shunt the pads to read-head shields and the slider substrate and thence to ground. The epoxy ball is easily applied and easily removed and can be used at different stages in the manufacturing process.
    Type: Grant
    Filed: November 5, 2007
    Date of Patent: November 23, 2010
    Assignee: SAE Magnetics (HK) Ltd.
    Inventors: Niraj Mahadev, Kazumasa Yasuda, Rudy Ayala
  • Patent number: 7837885
    Abstract: An embodiment of the present invention is an ABS design with a pitch ladder feature. This embodiment has an air flow squeezing channel which consists of one airflow blocker and three etching steps. The airflow blocker can be used to limit the incoming air flow from the leading edge of the ABS. Additionally, the embodiment contains an air channel that reduces altitude sensitivity by channeling air at the inner diameter into a sub-ambient pressure cavity.
    Type: Grant
    Filed: November 7, 2006
    Date of Patent: November 23, 2010
    Assignee: SAE Magnetics (HK) Ltd.
    Inventors: Ellis T. Cha, Zhu Feng, Xinjiang Shen, Sindy Yeung
  • Patent number: 7782569
    Abstract: A method for forming a protective bilayer on a magnetic read/write head or magnetic disk. The bilayer is formed as an adhesion enhancing underlayer and a protective diamond-like carbon (DLC) overlayer. The underlayer is formed of an aluminum or alloyed aluminum oxynitride, having the general formula AlOxNy or MezAlOxNy where Mez symbolizes Tiz, Siz or Crz and where x, y and z can be varied within the formation process. By adjusting the values of x and y the adhesion underlayer contributes to such qualities of the protective bilayer as stress compensation, chemical and mechanical stability and low electrical conductivity. Various methods of forming the underlayer are provided, including reactive ion sputtering, plasma assisted chemical vapor deposition, pulsed laser deposition and plasma immersion ion implantation.
    Type: Grant
    Filed: January 18, 2007
    Date of Patent: August 24, 2010
    Assignee: SAE Magnetics (HK) Ltd.
    Inventors: Shide Cheng, Zhu Feng, Ellis T. Cha
  • Patent number: 7760468
    Abstract: An apparatus allowing for a slider for use in a disk drive is disclosed. An embodiment of the present invention may include a leading side, a trailing side, at least two main rails, a slider surface with an air bearing surface, and at least one trench substantially parallel to the width of the slider. The trench in the air bearing surface results in a lower compression length of the slider and allows for particles to be channeled off of the disk surface.
    Type: Grant
    Filed: April 19, 2005
    Date of Patent: July 20, 2010
    Assignee: SAE Magnetics (HK) Ltd.
    Inventors: Ellis T. Cha, Guoqiang Zheng, Sindy Yeung
  • Patent number: 7701673
    Abstract: A gimbal design for a hard disk drive are disclosed. In one embodiment, a gimbal tongue is supported by a gimbal cross bar coupled to a suspension body by a pair of gimbal struts. A pair of grounding pads are mounted on either side of the leading edge of the gimbal tongue. A first limiter tab is coupled to the leading edge of the gimbal tongue and a second limiter tab is coupled to the trailing edge of the gimbal tongue. Notches on either side of the trailing edge limiter tab increase the strength of the tab. One or more cutouts allow the slider to be electrically coupled to bonding pads on the opposite side of the gimbal tongue. Angled slots at the juncture of the gimbal cross bar and the gimbal tongue relieve stress on the gimbal.
    Type: Grant
    Filed: May 17, 2005
    Date of Patent: April 20, 2010
    Assignee: SAE Magnetics (HK) Ltd.
    Inventors: Jeffery L. Wang, Hai Ming Zhou, Chi Hung Yuen, Yen Fu, Hong Tian
  • Patent number: 7701672
    Abstract: A loadbeam is locally stiffened by either, 1. the addition of strategically placed extra material to the loadbeam, 2. not removing material during the etching process to form the loadbeam, or 3. special forming, by crimping or bending, at specific sites on the beam. The use of local stiffening, when placed about the loadbeam dimple or between the dimple and flexure attachment points, with or without additional damping, can significantly improve the dynamical response of the loadbeam and eliminate vibrational modes of a slider mounted on the loadbeam during HDI interactions with disk surface asperities during disk drive operation.
    Type: Grant
    Filed: June 16, 2006
    Date of Patent: April 20, 2010
    Assignee: SAE Magnetics (HK) Ltd.
    Inventors: Qinghua Zeng, Chao-Hui Yang, Yen Fu, Ellis Cha
  • Patent number: 7684154
    Abstract: Gimbal designs are provided that minimize adverse dynamic performance of a HDD suspension, particularly subsequent to head-disk-interface (HDI) interactions. The improvement of operational performance can be seen in graphical representations of the vibrational modes of a gimbal mounted slider subsequent to such HDI interactions. Each gimbal design includes a ramp limiter formed as two separated arms connected by one or two transverse bars and a routing of conducting traces that relieves stress and minimally contacts these bars.
    Type: Grant
    Filed: August 1, 2006
    Date of Patent: March 23, 2010
    Assignee: SAE Magnetics (HK) Ltd.
    Inventors: Qinghua Zeng, Chao-Hui Yang, Yen Fu, Ellis Cha
  • Patent number: 7679857
    Abstract: In a system and method for a non-contact measurement of the fly height of a slider above a magnetic data storage medium using electrostatic force, a slider with a read/write head flies over a magnetic data storage medium. A series of distinct voltages are applied between the slider and the magnetic data storage medium, and corresponding read-back signals are recorded. Using the recorded read-back signals, coefficients for an empirical curve-fit equation are calculated. The coefficients are normalized and converted into a fly height measurement.
    Type: Grant
    Filed: August 27, 2008
    Date of Patent: March 16, 2010
    Assignee: SAE Magnetics (HK) Ltd.
    Inventors: Li-Yan Zhu, Chao-Hui Yang, Yen Fu, Ellis T. Cha
  • Patent number: 7675711
    Abstract: A system and method for measuring and neutralizing the electrical charge at the interface of a magnetic head and a magnetic storage medium, such as a disk, is disclosed. A surface treatment material is applied to the magnetic head. The surface treatment material matches the medium surface material on the surface of the magnetic storage medium. The surface treatment material on the magnetic read/write head may be a fluorinated carbon, such as a Fomblin Z-derivative, perfluoro alkyl trichlorosilane, a FC-722, or a fluorinated polymer. The surface treatment material can be applied to the magnetic head by a vapor deposition process or by a liquid immersion process. The charge on the head-disk interface can be measured by applying varying external charges to the head while reading a signal previously written to the disk.
    Type: Grant
    Filed: May 7, 2003
    Date of Patent: March 9, 2010
    Assignee: SAE Magnetics (HK) Ltd.
    Inventors: Zhu Feng, Ellis Cha, Xiaofeng Zhang
  • Patent number: 7617737
    Abstract: In a system and method for adjusting a static torque on a slider in a head-gimbal assembly, a substantially rigid mass is placed on an air-bearing surface (ABS) of a slider. A static attitude of the slider is measured, and an adjustment location and intensity for a flexure to yield a zero slider static attitude are calculated. The flexure is adjusted based on the measurement and calculations.
    Type: Grant
    Filed: December 21, 2006
    Date of Patent: November 17, 2009
    Assignee: SAE Magnetics (HK) Ltd.
    Inventors: Li-Yan Zhu, Chao-Hui Yang, Yen Fu, Ellis T. Cha
  • Patent number: 7455332
    Abstract: The overcoat of a slider (alumina) is recessed relative to the slider ABS by a non-abrasive CMP process sufficiently to prevent thermal protrusion of the overcoat during subsequent slider use in a hard disk drive. The CMP process involves the oscillatory and rotational compressional contact between the ABS surface of the slider and a polymerically pre-treated compliant pad that is sprayed by an aqueous alkali lubricating solution having a pH between about 9 and 10. The overcoat is thereby also softened by the lubricating solution and removed by the compressional contact and no use of abrasives is required.
    Type: Grant
    Filed: November 16, 2005
    Date of Patent: November 25, 2008
    Assignee: SAE Magnetics (HK) Ltd.
    Inventors: Winston Jose, Rudy Ayala, Niraj Mahadev