Patents Represented by Attorney, Agent or Law Firm Jonathan A. Small
  • Patent number: 6020223
    Abstract: A method of producing an improved thin film transistor structure is provided having no source/gate or drain/gate overlap. A laser-assisted doping technique is applied to fabricate such transistors. A radiation filter is employed, which is transparent to light at the photolithography wavelength, but reflective or opaque at the laser wavelength. Eliminating source/gate and drain/gate overlap significantly reduces or eliminates parasitic capacitance and feed-through voltage between source and gate. Short-channel a-Si:H thin film transistors may be obtained having high field effect mobilities. Improved pixel performance and pixel-to-pixel uniformity is provided.
    Type: Grant
    Filed: October 29, 1997
    Date of Patent: February 1, 2000
    Assignee: Xerox Corporation
    Inventors: Ping Mei, Rene A. Lujan, James B. Boyce, Christopher L. Chua, Michael G. Hack
  • Patent number: 6019796
    Abstract: A method of producing an improved thin film transistor structure is provided having no source/gate or drain/gate overlap. A laser-assisted doping technique is applied to fabricate such transistors. A radiation filter is employed, which is transparent to light at the photolithography wavelength, but reflective or opaque at the laser wavelength. Eliminating source/gate and drain/gate overlap significantly reduces or eliminates parasitic capacitance and feed-through voltage between source and gate. Short-channel a-Si:H thin film transistors may be obtained having high field effect mobilities. Improved pixel performance and pixel-to-pixel uniformity is provided.
    Type: Grant
    Filed: October 29, 1997
    Date of Patent: February 1, 2000
    Assignee: Xerox Corporation
    Inventors: Ping Mei, Rene A. Lujan, James B. Boyce, Christopher L. Chua, Michael G. Hack
  • Patent number: 6013161
    Abstract: A Co--Pt based magnetic alloy which has been doped with a relatively high amount of nitrogen, e.g., at or above 1 at. % is obtained having high coercivity, for example in the range of 1400 Oe or above, and an increased signal-to-noise ratio as compared to the same Co--Pt based alloy which has not been doped with nitrogen. The alloy is vacuum deposited, for example, by sputtering, and the nitrogen may be introduced from the sputtering gas or from the sputtering target. Other low-solubility elements providing the grain uniformity and isolation include: B, P, S, C, Si, As, Se and Te.
    Type: Grant
    Filed: October 28, 1997
    Date of Patent: January 11, 2000
    Assignee: Komag, Incorporated
    Inventors: Tu Chen, Tsutomu Tom Yamashita, John Ko-Jen Chen, Rajiv Yadav Ranjan, Keith Kadokura, Ting Joseph Yuen
  • Patent number: 5976326
    Abstract: A Co--Pt based magnetic alloy which has been sputtered with an oxide or nitride of a primary constituent of the magnetic layer, e.g., CoO below about 10 at. %, provides improved coercivity, squareness, and reduced noise as compared to magnetic alloys with oxygen introduced by other methods. The alloy is vacuum deposited, for example, by sputtering, and the oxide or nitride may be introduced from the sputtering target from which the magnetic layer materials come or from a separate sputtering target. Examples of such oxides and nitrides include CoO, Co.sub.2 0.sub.3, Co.sub.3 O.sub.4, CrO.sub.2, Cr.sub.2 O.sub.3, TiO.sub.2, Ta.sub.2 O.sub.5, Al.sub.2 O.sub.3, WO, CoN, Co.sub.2 N, TiN, TaN, CrN, NiN, etc.
    Type: Grant
    Filed: August 28, 1997
    Date of Patent: November 2, 1999
    Assignee: Komag, Incorporated
    Inventors: Rajiv Yadav Ranjan, Miaogen Lu, Tsutomu Tom Yamashita, Tu Chen
  • Patent number: 5948288
    Abstract: Formation of laser texture features simultaneously on the target surfaces of each side of magnetic recording disk is facilitated by optical and mechanical components permitting excellent balance of optical power between each target surface, excellent matching of the radial position of laser texture features between each target surface, and excellent focusing of laser beams on each target surface. Polarization of the source laser beam may be used to controllably balance and direct a single source beam into individual beam paths for each target surface. Handling, automation complexity, and manufacturing time is thereby reduced.
    Type: Grant
    Filed: May 28, 1996
    Date of Patent: September 7, 1999
    Assignee: Komag, Incorporated
    Inventors: David Treves, Thomas O'Dell
  • Patent number: 5908514
    Abstract: A new magnetic alloy exhibits high Hc and Ms while exhibiting excellent corrosion resistance, thereby providing ideal physical properties for high density recording applications. Other parameters of the media, such as SNR, PW50, and S are at least maintained, if not also improved. The alloy contains cobalt and up to 10 at. % Ni, up to 20 at. % Pt, up to 10 at. % Ta, up to 10 at. % Ti, and optionally up to 6 at. % B. The ratio of the tantalum to titanium in the alloy is between 3:1 and 1:3. The alloy is deposited by vacuum deposition (typically sputtering) on a similarly deposited non-magnetic alloy under layer. Nitrogen and/or oxygen may be introduced into the alloy during deposition to improve SNR. Other corrosion-resistant thin film alloys may also be obtained by the inclusion of Ta and Ti.
    Type: Grant
    Filed: October 24, 1996
    Date of Patent: June 1, 1999
    Inventors: Rajiv Yadav Ranjan, Tu Chen, Tsutomu Tom Yamashita, John Ko-Jen Chen
  • Patent number: 5851688
    Abstract: A Co--Pt based magnetic alloy which has been doped with a relatively high amount of nitrogen, e.g., at or above 1 at. % is obtained having high coercivity, for example in the range of 1400 Oe or above, and an increased signal-to-noise ratio as compared to the same Co--Pt based alloy which has not been doped with nitrogen. The alloy is vacuum deposited, for example, by sputtering, and the nitrogen may be introduced from the sputtering gas or from the sputtering target. Other low-solubility elements providing the grain uniformity and isolation include: B, P, S, C, Si, As, Se and Te.
    Type: Grant
    Filed: November 20, 1997
    Date of Patent: December 22, 1998
    Assignee: Komag, Inc.
    Inventors: Tu Chen, Tsutomu Tom Yamashita, John Ko-Jen Chen, Rajiv Yadav Ranjan, Keith Kadokura, Ting Joseph Yuen
  • Patent number: 5846648
    Abstract: A magnetic recording medium is provided with a structured nucleation layer. The structured nucleation layer comprises a fine-grained seed layer and an intermediate layer. The seed layer (e.g., NiAl, Ti, Cr--Cu, etc.) serves as a template for fine grained-growth of the intermediate layer. The intermediate (e.g., Cr, etc.) layer has preferred crystal textures and an appropriate lattice match to a subsequently deposited magnetic recording layer to allow epitaxial growth of the magnetic recording layer. The intermediate layer provides morphology and orientation to the magnetic recording layer. The magnetic recording layer (e.g., Co-alloy) includes a material which segregates to the alloy grain boundaries to isolate the grains thereof. Each grain of the magnetic recording layer is predominantly a single crystal of small size and uniformly spaced from adjacent grains. The easy axis of the magnetic recording material is predominantly in the plane of the disk, with a random in-plane orientation.
    Type: Grant
    Filed: February 18, 1997
    Date of Patent: December 8, 1998
    Assignee: Komag, Inc.
    Inventors: Tu Chen, Michinobu Suekane, Makoto Imakawa, Kazuhiko Mitarai
  • Patent number: 5751390
    Abstract: A transmissive, backlit color twisted-nematic or super-twisted-nematic liquid crystal display employing a front fiber-optic faceplate or optical equivalent as a front retaining element of a liquid crystal cell that increases viewing angle between the display and a viewer while minimizing or eliminating undesirable variations in luminance, contrast ratio and chromaticity is described. The fiber-optic faceplate or optical equivalent includes cylindrical optical features and interstitial cladding material of greater optical index than the cylindrical optical features. The interstitial cladding material may include an opaque mask blocking layer to prevent the interstitial apertures from diffracting off-axis light into an observer's viewing cone.
    Type: Grant
    Filed: December 12, 1996
    Date of Patent: May 12, 1998
    Assignee: Xerox Corporation
    Inventors: Gregory P. Crawford, Thomas G. Fiske, Louis D. Silverstein
  • Patent number: 5736013
    Abstract: A Co--Pt based magnetic alloy which has been sputtered with an oxide or nitride of a primary constituent of the magnetic layer, e.g., CoO below about 10 at. %, provides improved coercivity, squareness, and reduced noise as compared to magnetic alloys with oxygen introduced by other methods. The alloy is vacuum deposited, for example, by sputtering, and the oxide or nitride may be introduced from the sputtering target from which the magnetic layer materials come or from a separate sputtering target. Examples of such oxides and nitrides include CoO, Co.sub.2 O.sub.3, Co.sub.3 O.sub.4, CrO.sub.2, Cr.sub.2 O.sub.3, TiO.sub.2, Ta.sub.2 O.sub.5, Al.sub.2 O.sub.3, WO, CoN, Co.sub.2 N, TiN, TaN, CrN, NiN, etc.
    Type: Grant
    Filed: January 3, 1997
    Date of Patent: April 7, 1998
    Assignee: Komag, Inc.
    Inventors: Rajiv Yadav Ranjan, Miaogen Lu, Tsutomu Tom Yamashita, Tu Chen
  • Patent number: 5726730
    Abstract: Methods for making plates which have columnar features approximately in the direction of light propagation which are capable of total internal reflection, a controllable numeric aperture (NA) at input and output surfaces, rotational azimuthal averaging and translation of the object plane from a back surface of the plate to a front surface of the plate and are optical equivalent of a FOFP. These plates are made from a range of materials including a variety of monomer or polymer networks.The resultant plates contain adjacent areas with differing refractive indices which result in a substrate containing a plurality of cylindrical features whose boundaries are defined by a discontinuity of refractive indices wherein the index of refraction within the cylindrical features is greater than the index of refraction at the boundaries and external to the cylindrical features.
    Type: Grant
    Filed: December 19, 1996
    Date of Patent: March 10, 1998
    Assignee: Xerox Corporation
    Inventors: Gregory P. Crawford, Thomas G. Fiske, Louis D. Silverstein
  • Patent number: 5695387
    Abstract: Definition of the required geometry of the air bearing surface ("ABS") of a magnetic head slider is achieved while providing an ABS which exhibits low wear, low friction, and low stiction at its interface with a disk surface, by securely embedding monocrystalline diamond particles into a lapping plate, removing substantially all particles from the plate which are not firmly affixed thereto, and lapping the slider in a linear, X-Y direction at a relatively high lapping pressure. Material susceptible to being dislodged during CSS is removed during the lapping process. Thus, the incidence of material dislodging from the ABS and increasing wear-induced stiction is substantially reduced, resulting in improved CSS performance. A desired microtexture is also applied to the ABS. Reduced pole tip recession is also observed.
    Type: Grant
    Filed: February 21, 1995
    Date of Patent: December 9, 1997
    Assignee: Komag, Inc.
    Inventors: Mark D. Moravec, Tu Chen, Tracy L. Scott, Kyou Haeng Lee, Tsutomu Tom Yamashita, Tam Huu-Minh Nguyen
  • Patent number: 5658659
    Abstract: Media according to the present invention is comprised of individual magnetic grains as small as 300 .ANG. or smaller in diameter, which are uniformly spaced apart by a distance between 5 and 50 .ANG. by a solid segregant. This media will typically exhibit coercivity and remanent coercivity squareness of at least 0.8 each, a switching field distribution of less than 0.2, and a coercivity of at least 1500 Oe (with a minimum required Pt content), while simultaneously providing the lowest media jitter noise for optimum magnetic performance. The media is deposited at a low partial pressure of water and in the presence of an optimum amount of contributant gas on a doped nucleation layer for grain growth control.
    Type: Grant
    Filed: August 5, 1994
    Date of Patent: August 19, 1997
    Assignee: Komag, Inc.
    Inventors: Tu Chen, Rajiv Yadav Ranjan, Tsutomu Tom Yamashita, Miaogen Lu, Keith Kadokura, John Ko-Jen Chen, Ting Joseph Yuen
  • Patent number: 5631094
    Abstract: A new magnetic alloy exhibits high Hc and Ms while exhibiting excellent corrosion resistance, thereby providing ideal physical properties for high density recording applications. Other parameters of the media, such as SNR, PW50, and S are at least maintained, if not also improved. The alloy contains cobalt and up to 10 at. % Ni, up to 20 at. % Pt, up to 10 at. % Ta, up to 10 at. % Ti, and optionally up to 6 at. % B. The ratio of the tantalum to titanium in the alloy is between 3:1 and 1:3. The alloy is deposited by vacuum deposition (typically sputtering) on a similarly deposited non-magnetic Ni alloy under layer. Nitrogen and/or oxygen may be introduced into the alloy during deposition to improve SNR. Other corrosion-resistant thin film alloys may also be obtained by the inclusion of Ta and Ti.
    Type: Grant
    Filed: December 1, 1994
    Date of Patent: May 20, 1997
    Assignee: Komag, Incorporated
    Inventors: Rajiv Y. Ranjan, Tu Chen, Tsutomu T. Yamashita, John K.-J. Chen
  • Patent number: 5595768
    Abstract: Reflection of a generated radiation beam (e.g., laser) from a disk substrate during radiation-induced texturing such that the reflection interferes with the generated radiation beam is eliminated as follows: the beam path of the laser beam is passed through focusing optics to focus the beam to a spot on the substrate surface; the beam path is offset from the center of the focusing optics so that the focusing optics bend the beam path, and further so that the beam is angled from normal to the surface of the disk, for example by between 2 and 5 degrees; and that portion of the beam reflected by the disk surface is blocked by appropriate means prior to its impinging upon the source of the generated radiation beam.
    Type: Grant
    Filed: November 2, 1995
    Date of Patent: January 21, 1997
    Assignee: Komag, Incorporated
    Inventors: David Treves, Hong Fu, Thomas O'Dell
  • Patent number: 5574836
    Abstract: An object-oriented display system which displays an image of a graphical object on a display device, the position at which the object is displayed being a function of the position from which a viewer views the display device so as to simulate an interactive, three-dimensional viewing environment.An object-oriented display system, in which the highest discernible level of data in the frame buffer is an object with preserved association of pixels to the object allows dynamic selection of view. View position data may be employed on-the-fly to dynamically determine display from an arbitrary view position. Object data storage in tile format allows for rapid and simplified display generation.
    Type: Grant
    Filed: January 22, 1996
    Date of Patent: November 12, 1996
    Inventor: Raymond M. Broemmelsiek
  • Patent number: 5323026
    Abstract: A diode laser of the buried heterostructure type with transverse injection and a lateral bipolar transistor structure are monolithically and coaxially formed in the same set of semiconductor layers to make an integral laser device that emits a constant level of optical power stabilized against unpredictable variations. The base region of the transistor structure is formed coaxially with the laser waveguide, so that laser power passes into or through the transistor base. Electrical feedback is provided from the transistor to the laser via a resistor between the collector of the transistor and the anode of the laser, thereby controlling the current delivered by an external current source to the laser.
    Type: Grant
    Filed: August 3, 1992
    Date of Patent: June 21, 1994
    Assignee: Xerox Corporation
    Inventor: Thomas L. Paoli
  • Patent number: 5267255
    Abstract: Modulation-induced thermal crosstalk between the independently addressable lasers of a monolithic multilaser array is reduced or eliminated by forming each laser with two optically coupled active regions, an amplifier region and a modulator region. Modulation of the laser output is achieved by varying the internal optical loss of the modulator region, known as Q-switching. In one form, control of this loss is achieved by varying the reverse bias voltage applied to the modulation region. In another form, control of this loss is achieved by selectively connecting and disconnecting regions of p-type and n-type material in the modulator region together. In a third form, control of this loss is achieved by selectively connecting and disconnecting the modulator region to ground potential. In a fourth form, control of this loss is achieved by increasing the amplifier current to allow lasing and simultaneously offset any thermal effects produced by the increased optical power emitted.
    Type: Grant
    Filed: February 25, 1992
    Date of Patent: November 30, 1993
    Assignee: Xerox Corporation
    Inventor: Thomas L. Paoli
  • Patent number: H1264
    Abstract: In situ geometrical and stoichiometric properties of deposited films are brought about by employing a scanned irradiation source directed to a spot which is scanned across the growth surface in a chemical vaGOVERNMENT RIGHTSThe Government has certain rights in this invention pursuant to Contract No. 86F173100 awarded by the Defense Advanced Research Projects Agency (DARPA).
    Type: Grant
    Filed: April 24, 1991
    Date of Patent: December 7, 1993
    Assignee: Xerox Corporation
    Inventors: John E. Epler, Harlan F. Chung, Thomas L. Paoli
  • Patent number: RE35335
    Abstract: A bicycle frame manufactured of one or more continuous fiber composite tubes, wherein the tubes are joined to one another without lugs by overlaying the joints with resin impregnated continuous fiber composite material and clamping the joints in static pressure molds. Gussets are integrally formed as part of the joints. One or more of the tubes may be metal, preferably titanium. The bicycle frame is provided with metal drop outs which are also preferably titanium.
    Type: Grant
    Filed: October 25, 1993
    Date of Patent: September 24, 1996
    Inventor: Craig D. Calfee