Patents Assigned to Data Storage Institute
  • Patent number: 6674201
    Abstract: A spindle motor (10) including a stator component (16), a rotor component (18), including a hub (14) for supporting one or more discs, and a bearing assembly between tHe components, formed of a journal bearing (54) and a thrust bearing (52), wherein the journal bearing (54) is an aerodynamic bearing and the thrust bearing is adapted to function in a bi-directional manner and includes an annular member (30) projecting radially from one of the components into an associated recess (76) formed in the other of the components. Preferably, the annular member has two opposed bearing faces (68,70) arranged adjacent corresponding bearing surfaces of the recess, and a hydrodynamic bearing is formed between the respective bearing faces and surfaces.
    Type: Grant
    Filed: April 25, 2000
    Date of Patent: January 6, 2004
    Assignee: Data Storage Institute
    Inventors: Zhejie Liu, QiDe Zhang, Shixin Chen, Teck Seng Low
  • Patent number: 6641702
    Abstract: The present invention is directed to a sputtering device for depositing multi-layer films on a substrate, the sputtering device comprising at least one planar-magnetron-sputtering-cathode and at least one facing-targets-sputtering-cathode housed in a single vacuum chamber, and adapted such that each planar-magnetron-sputtering-cathode and facing-targets-sputtering-cathode can be selectively positioned for sputtering deposition onto a substrate.
    Type: Grant
    Filed: September 26, 2001
    Date of Patent: November 4, 2003
    Assignee: Data Storage Institute
    Inventors: Jian Zhong Shi, Jian Ping Wang
  • Patent number: 6633439
    Abstract: The present invention provides an improved optical reading and recording system utilizing optical system employing an aspherical solid immersion lens (SIL). The improved optical system has an aspherical SIL between an objective lens and the recording media. The aspherical SIL reduces the focused electromagnetic radiation beam spot size by providing an increased numeric aperture (NA) of the optical system. The aspherical surface of the SIL provide greater manufacturing and operating tolerances between the objective lens and the aspherical SIL. Greater manufacturing tolerances provide an easier to manufacture optical system. Increased ease of manufacture reduces the cost of optical systems.
    Type: Grant
    Filed: November 16, 2000
    Date of Patent: October 14, 2003
    Assignee: Data Storage Institute
    Inventors: Baoxi Xu, Minyu Liu, Tow Chong Chong, Gaoqiang Yuan
  • Patent number: 6633457
    Abstract: An actuator assembly for positioning read/write heads above a data storage media comprises a pivotally mounted carriage arm assembly with a voice coil and a magnetic device having a plurality of poles for generating a magnetic field. The voice coil is positioned with its effective portions crossing through the magnetic field to generate at least one pair of driving forces in a direction substantially orthogonal to a seeking direction of the read/write heads. The carriage arm driven by said pair of forces has substantially no reacting force generated onto the pivot so that the servo bandwidth of the head positioning assembly can be improved and achieves a high degree of head positioning accuracy.
    Type: Grant
    Filed: July 25, 2000
    Date of Patent: October 14, 2003
    Assignee: Data Storage Institute
    Inventors: Huai Lin, Teck Seng Low, Zhimin He, Shixin Chen, Qinghua Li
  • Patent number: 6624553
    Abstract: A microactuator (30) is provided for positioning a read/write head relative to a mounting region of a head suspension assembly of a magnetic disk drive. The microactuator (30) comprises a substantially C-shaped member (32) having a first end (34) and a second end (38) defining an air gap (42) therebetween. In one embodiment the member (32) is a piezoelectric bimorph expander; in another embodiment the member is a ferromagnetic core. Under an applied electric or magnetic field as appropriate, the size of the air gap (42) may be altered and, because the member (32) is resilient, the original air gap may be restored on removing the applied field. The microactuator may be mounted on the load beam of the head suspension assembly, or between the load beam and head slider supporting the read/write head.
    Type: Grant
    Filed: April 4, 2001
    Date of Patent: September 23, 2003
    Assignee: Data Storage Institute
    Inventors: Kodikkunnathukulangara Sivadasan, Guoxiao Guo
  • Patent number: 6611389
    Abstract: A method of determining a clearance between a magnetic transducer and a magnetic recording medium during a track seeking operation, the magnetic recording medium being moveable with respect to the transducer and including at least a test track and a reference track, which method comprises the steps of: at least partially erasing a predetermined area of the recording medium including at least one test track and one reference track; writing a first series of predetermined magnetic transitions along a spiral trace, formed by seeking operation of the transducer, on the at least one test track in the predetermined area; reading the test track and obtaining a pulse width of signals read back from the test track (test track pulse width) at a predetermined amplitude level; writing a further series of predetermined magnetic transitions identical to the first series on a reference track of the recording medium in the predetermined area; reading the reference track and obtaining, a pulse width of signals read back from
    Type: Grant
    Filed: October 7, 1999
    Date of Patent: August 26, 2003
    Assignee: Data Storage Institute
    Inventors: Bo Liu, Qisuo Chen
  • Patent number: 6597618
    Abstract: A circuit for controlling a read operation for a magnetic random access memory (MRAM) comprising an array of magnetic tunnel junctions (MTJ) having conducting row and column lines attached thereto. The circuitry comprises a current supply for providing a read current, and a row selector for selecting a row containing a junction to be read and applying the read current to that row with the respective row line. An unselected row switch switches to at least some of the row lines not connected to the MTJ to be read, and a voltage source applies, via the unselected row switch, a voltage to each of the unselected row lines that is substantially identical in level to the voltage on the selected row line. A column selector selects the column line connected to the array containing the MTJ to be read, and a voltage detector for detecting the voltage across the MTJ to be read via the selected column and row lines.
    Type: Grant
    Filed: June 27, 2002
    Date of Patent: July 22, 2003
    Assignee: Data Storage Institute
    Inventors: Yuankai Zheng, Yihong Wu, Xiaoyan Wang, Dan You
  • Publication number: 20030133218
    Abstract: The present invention relates to controlling an actuator for positioning a read/write head in storage devices such as disk drives. More specifically, the invention relates to using a sensor to detect the disk vibration amplitude perpendicular to the disk surface, and using feed forward control to cancel or counteract the tendency of the read/write head to deviate off-track due to disk vibration. Various approaches are proposed to detect the disk vertical vibration.
    Type: Application
    Filed: June 4, 2002
    Publication date: July 17, 2003
    Applicant: Data Storage Institute
    Inventors: Guoxiao Guo, Jingliang Zhang, Zhimin He, Eng Hong Ong
  • Patent number: 6576867
    Abstract: A method and apparatus for the removal of mold flash from an IC device using a non-thermal laser ablation method. Ablation is achieved under conditions in which the mold flash is converted to plasma under short laser pulses which do not give sufficient time or energy for significant thermal processes to occur. As a result, the heat sink underneath the mold flash is prevented from heating up due to lack of heat transfer, thereby protecting the heat sink from heat damages. According to one feature of the invention, a mask is provided to protect the molded packaging of the IC device from the laser beam. The mask has at least one hole which corresponds to the heat sink of the device wherethrough the laser beam can pass. According to another feature of the invention, a large beam diameter is provided to increase the efficiency of the deflashing process.
    Type: Grant
    Filed: February 12, 2002
    Date of Patent: June 10, 2003
    Assignees: Advanced Systems Automation Ltd., Data Storage Institute
    Inventors: Yong Feng Lu, Yak Hui Sim, Qiong Chen, Long Chen Lai, Bin Othman Rustam
  • Publication number: 20030102863
    Abstract: A magnetic force microscopy (MFM) probe has an elongated probe tip with a planar surface onto which a uniformly thick magnetic film is formed. The magnetic film may comprise either a seed layer, an exchanged coupled ferromagnetic/anti-ferromagnetic double layer, and a capping layer, or a seed layer, an antiferromagnetic layer, a synthetic triple layer consisting of a thin non-magnetic layer sandwiched by two ferromagnets, and a capping layer. The multiple layers are annealed below the Neel temperature of the anti-ferromagnetic layer and field cooled to establish an unidirectional exchange bias along the tip surface. The coated portion of the tip is made sufficiently long so that the interaction between the tip and sample mainly happens at the bottom end of the tip.
    Type: Application
    Filed: March 13, 2002
    Publication date: June 5, 2003
    Applicant: Data Storage Institute
    Inventor: Yihong Wu
  • Publication number: 20030091738
    Abstract: A method of forming at least one layer on a substrate surface by vacuum deposition of particles onto the substrate surface, the method comprising the step of moving at least part of the substrate at high speed during vacuum deposition in a first direction parallel to the substrate surface. The method reduces the amount of macroparticles in a layer or layers deposited on the substrate, and controls the microstructure and crystallographic structure of the deposited layer or layers. Also disclosed are devices for performing the method, and resulting products, for example a hard disk thin film media.
    Type: Application
    Filed: June 24, 2002
    Publication date: May 15, 2003
    Applicant: DATA STORAGE INSTITUTE
    Inventors: Jian-Ping Wang, Jianzhong Shi, Tow Chong Chong
  • Patent number: 6545378
    Abstract: An electric spindle motor for use in precision instruments such as hard disk drives comprises a stationary sub-assembly and a rotary sub-assembly movable relative to the stationary sub-assembly for carrying magnetic disks. The electric spindle motor has an integrated bearing system including a hydrodynamic journal bearing for providing desired radial load and a magnetic bearing for reducing friction resistance during staring/stopping and running of the electric spindle motor. The rotary sub-assembly is suspended from the stationary sub-assembly by the activation of the magnetic bearing during the rotating of the electric spindle motor. The electric spindle motor having integrated hydrodynamic journal bearing and magnetic bearing of the present invention is capable of high speed and high accuracy running, providing increased radial load and stiffness, and reduces the friction resistance therefore improves the performance and power saving.
    Type: Grant
    Filed: December 21, 2001
    Date of Patent: April 8, 2003
    Assignee: Data Storage Institute
    Inventors: Shixin Chen, Qide Zhang
  • Publication number: 20030062347
    Abstract: This invention relates to a method and apparatus for deflashing integrated circuit (IC) packages by laser irradiation. The method and apparatus include two lasers scanning flash area for performing deflashing operation. CO2 laser is used to remove top layer of flash and YAG laser is used to remove the thin layer of flash remained after CO2 laser deflashing. CO2 laser deflashing and following YAG laser deflashing can effectively remove flash and avoid damage of heat sinks as well as leads and bars in the IC packages.
    Type: Application
    Filed: January 29, 2002
    Publication date: April 3, 2003
    Applicant: Data Storage Institute
    Inventors: Wen Dong Song, Minghui Hong, Chengwu An, Yong Feng Lu
  • Patent number: 6522050
    Abstract: A micro actuator driven load beam mechanism for use in a head suspension assembly is disclosed. The mechanism includes a load beam including a proximal end portion and a distal end portion, a hinge portion connecting the proximal and distal end portions of the load beam for permitting relative movement therebetween, and a piezoelectric beam connecting the proximal and distal end portions, the piezoelectric beam being selectively energizable to effect relative movement between the proximal and distal end portions. The load beam includes a pocket for holding at least one end of the piezoelectric beam. The piezoelectric beam and the pocket may be inclined relative to a hinge plane to control the load beam twist and minimize the altitude variations of the beam tip.
    Type: Grant
    Filed: July 3, 2001
    Date of Patent: February 18, 2003
    Assignee: Data Storage Institute
    Inventors: Kodikkunnathukulangara Sivadasan, Guoxiao Guo
  • Patent number: 6518540
    Abstract: A method and apparatus for creating ablation-free visible markings on a multi-layer hard disk magnetic storage media by laser-induced deformation while maintaining the integrity of the protective carbon layer, and without destroying the multi-layered structure of the media. The apparatus includes a laser generator, a rotatable optical plate and a beamsplitter by which the fluence of the beam can be controlled without altering the power setting to the laser generator, a beam sampler for determining the fluence of the beam, and an optical plate which acts with the beamsplitter to eliminate unwanted reflection of the laser beam. The laser beam is steered by a beamsteerer to a hard disk held in a material handling unit. This technique is highly suitable for marking or labeling finished hard disks for the purposes of identification and traceability, without creating any short-term or long-term contamination problems. The corresponding storage media so marked are also claimed.
    Type: Grant
    Filed: June 14, 1999
    Date of Patent: February 11, 2003
    Assignee: Data Storage Institute
    Inventors: Teng Soon Wee, Lian Boon Koh, Daming Liu, Yuan Yuan, Yong Feng Lu, Jui Kiat Goh, Kuan Teck Chang
  • Publication number: 20030019745
    Abstract: An oblique sputtering deposition apparatus is provided for preparing a thin film. A collimator having angled passages for filtering out particles from stray directions is placed between the substrate and the incident particle flux. The angle of the passages can be adjusted from about 0 to about 90° with respect to the substrate normal according to requirements. The oblique incidence of particle flux brings forms a column structure which is also angled.
    Type: Application
    Filed: March 14, 2002
    Publication date: January 30, 2003
    Applicant: Data Storage Institute.
    Inventors: Jian-Ping Wang, Jianzhong Shi
  • Publication number: 20030001457
    Abstract: In a flat panel display, a laser spacer array is created on the transparent substrate 10′ to maintain the two substrates at a pre-determined spacing in the finished panel. The spacers 20 are distributed between the two substrates, which are sealed using sealant 18 resulting in a cell gap with pre-determined spacing distance.
    Type: Application
    Filed: September 19, 2001
    Publication date: January 2, 2003
    Applicant: DATA STORAGE INSTITUTE
    Inventors: Weijie Wang, Minghui Hong, Chengwu An, Yong Feng Lu
  • Patent number: 6500497
    Abstract: A method of producing a patterned magnetic nanostructure is disclosed. The method includes providing a substrate having a non-magnetic single layer or multi layer film that can be converted into a magnetic state by annealing and/or mixing. The method further includes positioning a mask having a desired pattern and resolution associated with the patterned magnetic nanostructure on or over the film. The method additionally includes subjecting the mask-covered substrate to a beam of radiation (focussed or unfocussed) having sufficient energy to locally anneal and/or mix the non-magnetic or weak-magnetic single-layer or multi layer film. Because of the mask effect, only the desired portions of the non-magnetic film are exposed to the beam of radiation. As such, the desired portions of the non-magnetic film are changed from a non-magnetic to a magnetic state to produce an array of magnetic elements in a non-magnetic matrix. The size of each magnetic element is dependent on the resolution of mask.
    Type: Grant
    Filed: April 19, 2002
    Date of Patent: December 31, 2002
    Assignee: Data Storage Institute
    Inventors: Jian-Ping Wang, Tie Jun Zhou, Tow Chong Chong
  • Patent number: 6437930
    Abstract: A method and apparatus of detecting variations in a clearance distance between a magnetic read/write transducer and a magnetic recording disk having a clearance detection burst recorded thereon. The clearance detection burst has at least two groups of bit patterns each having different transition densities. The method may have the steps of obtaining a readback signal from the at least two groups of bit patterns, the readback signal being sensitive to variations in the clearance; detecting the amplitude of the readback signal of a first group. The amplitudes of the readback signals are detected and then compared to provide an indication of a variation in the clearance.
    Type: Grant
    Filed: October 20, 1999
    Date of Patent: August 20, 2002
    Assignee: C/O Data Storage Institute
    Inventors: Bo Liu, Shengbin Hu
  • Patent number: 6366081
    Abstract: A method and apparatus are provided for efficiently testing magnetic media in which a read level test is performed using an approximation for an average signal level in determining a test threshold and while reading data and testing against the approximate average read signal level, the data signal level is averaged to determine the real average read signal and this value is then used to adjust the results of the comparisons performed against the approximate average read level.
    Type: Grant
    Filed: February 25, 2000
    Date of Patent: April 2, 2002
    Assignee: Data Storage Institute
    Inventors: Seng Ghee Tan, Thomas Yun Fook Liew, Teck Ee Loh, Udaya Ahangama W. Silva