Patents Represented by Attorney Wan Yee Cheung
  • Patent number: 7145347
    Abstract: A method and apparatus for measuring alternating current (AC) and direct current (DC) characteristics of a plurality of semiconductor devices. A ring oscillator generates pulses to drive the plurality of semiconductor devices under test. Current/Voltage (IV) and transfer characteristics of the plurality of semiconductor devices are measured using only DC input/output.
    Type: Grant
    Filed: August 31, 2004
    Date of Patent: December 5, 2006
    Assignee: International Business Machines Corporation
    Inventors: Manjul Bhushan, Mark B. Ketchen
  • Patent number: 7087471
    Abstract: In a FinFET integrated circuit, the fins are formed with a reduced body thickness in the body area and then thickened in the S/D area outside the body to improve conductivity. The thickening is performed with epitaxial deposition while the lower portion of the gates are covered by a gate cover layer to prevent thickening of the gates at the fin level, which may short the gate to the S/D.
    Type: Grant
    Filed: March 15, 2004
    Date of Patent: August 8, 2006
    Assignee: International Business Machines Corporation
    Inventor: Jochen C. Beintner
  • Patent number: 7085658
    Abstract: A method and apparatus for monitoring a plurality of semiconductor devices is disclosed. At least one array of 2n semiconductor circuits is provided. A clock ring oscillator provides a clock signal. The clock signal drives a frequency divider followed by an n-stage binary counter. The outputs from the counter's stages drive an n-input decoder which sequentially addresses each semiconductor circuit. An output signal from each semiconductor circuit is measured and read out over a common bus, where a distribution of the output signals is a measure of a distribution of a parameter of interest.
    Type: Grant
    Filed: October 20, 2004
    Date of Patent: August 1, 2006
    Assignee: International Business Machines Corporation
    Inventors: Manjul Bhushan, Mark B. Ketchen
  • Patent number: 7068865
    Abstract: The present invention is a method and an apparatus for thermo-optic control of optical signals using photonic crystal structures. In one embodiment, a first portion of a split signal is modulated by propagating the signal through a photonic crystal waveguide in which two electrical contacts are laterally spaced from the waveguide region by a plurality of apertures formed through the photonic crystal substrate. A voltage applied across the electrical contacts causes resistive heating of the proximate photonic crystal waveguide through which the signal propagates, thereby modulating the temperature relative to an un-modulated second portion of the split signal that is used as a reference.
    Type: Grant
    Filed: January 12, 2004
    Date of Patent: June 27, 2006
    Assignee: International Business Machines Corporation
    Inventors: Hendrik F. Hamann, Sharee J. McNab, Martin P. O'Boyle, Yurii A. Vlasov
  • Patent number: 7021124
    Abstract: One embodiment of the present method and apparatus for detecting leaks in a fluid cooling system enables a user to rapidly detect fluid leaks in the vicinity of a microprocessor chip or other delicate item. In one embodiment, the invention comprises a detector and a border coupled to the detector and disposed peripherally about a protected item (e.g., the microprocessor chip or other delicate item). In one embodiment, the border is a layered structure that is adapted to complete an electrical circuit with the detector when the border comes into contact with fluid.
    Type: Grant
    Filed: August 27, 2004
    Date of Patent: April 4, 2006
    Assignee: International Business Machines Corporation
    Inventors: Robert J. Von Gutfeld, Hendrik F. Hamann, Jeffrey D. Gelorme
  • Patent number: 6960782
    Abstract: Described is an electronic device comprising a junction formed between a first fullerene layer having a first doping concentration and a second fullerene layer having a second doping concentration different from the first doping concentration. The first doping concentration may be zero. The first and/or the second fullerene layer may be a monolayer. The second fullerene layer may comprise an electron donor. One example of such a device is a diode wherein the first fullerene layer is connected to an anode and the second fullerene layer is connected to a cathode. Another example is a field effect transistor wherein the first fullerene layer serves as a gate region and the second fullerene layer serves as a channel region. The second fullerene layer may alternatively comprise an electron acceptor. At least one of the first and second fullerene layers may be formed from C60, or may consist of a single bucky ball.
    Type: Grant
    Filed: April 28, 2003
    Date of Patent: November 1, 2005
    Assignee: International Business Machines Corporation
    Inventors: Rolf Allenspach, Urs T. Duerig, Walter Riess, Reto Schlittler
  • Patent number: 6949397
    Abstract: A method for protecting a material of a microstructure comprising said material and a noble metal layer against undesired galvanic etching during manufacture comprises forming on the structure a sacrificial metal layer having a lower redox potential than said material, the sacrificial metal layer being electrically connected to said noble metal layer.
    Type: Grant
    Filed: January 11, 2002
    Date of Patent: September 27, 2005
    Assignee: International Business Machines Corporation
    Inventors: Michel Despont, Roy H. Magnuson, Ute Drechsler
  • Patent number: 6935364
    Abstract: A valve comprising a housing having an inlet and spaced therefrom an outlet, a passageway extending between the inlet and the outlet, and a mechanism located in the passageway for controlling the flow of a fluid between the inlet and the outlet, the mechanism including a valve assembly movable between a first open position spaced from a co-operating valve seat and a second closed position at which the valve assembly sealingly engages the valve seat, in which the valve assembly is biased towards the second closed position using a magnet-operated mechanism.
    Type: Grant
    Filed: October 26, 2000
    Date of Patent: August 30, 2005
    Assignee: The BOC Group plc
    Inventors: Antulio Tarazona, John Cambridge Smith, Ian Currington
  • Patent number: 6883033
    Abstract: A system and method for controlling the rates at which application workload, e.g., TCP connection requests, is admitted to a collection of servers, such as a server farm of an application service provider (ASP) that hosts Internet World Wide Web (WWW) sites of various owners. The system and method are intended to operate in an environment in which each customer has a workload-based SLA for each type of application hosted by the provider and used by the customer. The system and method achieve support (minimum, maximum) TCP connection requests for multiple customers and applications. According to one aspect, the system and method guarantee, control and deliver TCP connection-based workload SLA's to customers whose applications are hosted by the server farm with the use of a workload regulator that operates by regulating only new TCP connection request packets while transparently passing existing TCP connection packets and other request packets received for customers.
    Type: Grant
    Filed: February 20, 2001
    Date of Patent: April 19, 2005
    Assignee: International Business Machines Corporation
    Inventors: Kiyoshi Maruyama, Shun Shing Chan, Jarir Kamel Chaar, Jean A. Lorrain, Miram Zohar, David Alson George
  • Patent number: 6857025
    Abstract: A highly scalable system and method for supporting (mim,max) based Service Level Agreements (SLA) on outbound bandwidth usage for a plurality of customers whose applications (e.g.,Web sites) are hosted by a server farm that consists of a very large number of servers. The system employs a feedback system that enforces the outbound link bandwidth SLAs by regulating the inbound traffic to a server or server farm. Inbound traffic is admitted to servers using a rate denoted as Rt(i,j), which is the amount of the ith customer's jth type of traffic that can be admitted within a service cycle time to servers which support the ith customer. A centralized device computes Rt(i,j) based on the history of admitted inbound traffic to servers, the history of generated outbound traffic from servers, and the SLAs of various customers. The Rt(i,j) value is then relayed to one or more inbound traffic limiters that regulate the inbound traffic using the rates Rt(i,j) in a given service cycle time.
    Type: Grant
    Filed: April 5, 2000
    Date of Patent: February 15, 2005
    Assignee: International Business Machines Corporation
    Inventors: Kiyoshi Maruyama, German Goldszmidt, Jean Lorrain, Karen Appleby-Hougham
  • Patent number: 6833573
    Abstract: A magnetic memory cell that uses a curved magnetic region to create magnetic anisotropy is provided by the present invention. The magnetic memory cell is created from a free magnetic layer, a barrier layer and a reference magnetic layer. The magnetic layers are constructed such that they have portions that are curved with respect to a first axis and straight with respect to a second perpendicular axis. These curved portions result in a magnetic memory cell that has an easy axis that is parallel to the first axis and a hard axis that is perpendicular to the easy axis. In addition, the resulting magnetic memory cell's coercivity is independent of it's thickness. Thus, the magnetic memory cell is well adapted to being scaled down without increasing the likelihood of thermally induced errors.
    Type: Grant
    Filed: July 18, 2003
    Date of Patent: December 21, 2004
    Assignee: International Business Machines Corporation
    Inventor: Daniel Worledge
  • Patent number: 6815296
    Abstract: A method of forming a silicon-on-insulator (SOI) metal oxide semiconductor field effect transistor (MOSFET) device is provided. The SOI MOSFET device includes a polysilicon back-gate which controls the threshold voltage of a polysilicon-containing front-gate. The back-gate functions as a dynamic threshold voltage control system in the SOI MOSFET device because it is suitable for use during circuit/system active periods and during circuit/system idle periods.
    Type: Grant
    Filed: September 11, 2003
    Date of Patent: November 9, 2004
    Assignee: International Business Machines Corporation
    Inventors: Robert H. Dennard, Wilfried E. Haensch, Hussein I. Hanafi
  • Patent number: 6815278
    Abstract: The invention provides integrated semiconductor devices that are formed upon an SOI substrate having different crystal orientations that provide optimal performance for a specific device. Specifically, an integrated semiconductor structure including at least an SOI substrate having a top semiconductor layer of a first crystallographic orientation and a semiconductor material of a second crystallographic orientation, wherein the semiconductor material is substantially coplanar and of substantially the same thickness as that of the top semiconductor layer and the first crystallographic orientation is different from the second crystallographic orientation is provided. The SOI substrate is formed by forming an opening into a structure that includes at least a first semiconductor layer and a second semiconductor layer that have different crystal orientations. The opening extends to the first semiconductor layer.
    Type: Grant
    Filed: August 25, 2003
    Date of Patent: November 9, 2004
    Assignee: International Business Machines Corporation
    Inventors: Meikei Ieong, Min Yang
  • Patent number: 6816431
    Abstract: A magnetic random access memory circuit comprises a plurality of magnetic memory cells, each of the memory cells including a magnetic storage element having an easy axis and a hard axis associated therewith, and a plurality of column lines and row lines for selectively accessing one or more of the memory cells, each of the memory cells being proximate to an intersection of one of the column lines and one of the row lines. Each of the magnetic memory cells is arranged such that the easy axis is substantially parallel to a direction of flow of a sense current and the hard axis is substantially parallel to a direction of flow of a write current.
    Type: Grant
    Filed: May 28, 2003
    Date of Patent: November 9, 2004
    Assignee: International Business Machines Corporation
    Inventors: Yu Lu, William Robert Reohr, Roy Edwin Scheuerlein
  • Patent number: 6813409
    Abstract: An optical switch comprises input channels with input optical free-space elements, an intermediate optical free-space element, and input tunable optical lenses with adjustable projection characteristic for projecting lightwaves received from the input optical free-space elements into the intermediate optical free-space element. The switch further comprises output channels with output optical free-space elements, and output tunable optical lenses with adjustable reception characteristic for capturing the lightwave from the intermediate optical free-space element and for feeding the lightwave to the output optical free-space elements. The optical switch can be integrated into a substrate. The tunable lens can be implemented with an individually tunable heater. By adjusting the heaters one can control the projection characteristic of the light beam emitted into a free-space element. Also an asymmetrical switch arrangement is possible.
    Type: Grant
    Filed: October 10, 2002
    Date of Patent: November 2, 2004
    Assignee: International Business Machines Corporation
    Inventor: Folker Horst
  • Patent number: 6803266
    Abstract: A process for passivating the semiconductor-dielectric interface of a MOS structure to reduce the interface state density to a very low level. A particular example is a MOSFET having a tungsten electrode that in the past has prevented passivation of the underlying semiconductor-dielectric interface to an extent sufficient to reduce the interface state density to less than 5×1010/cm2−eV. Though substantially impervious to molecular hydrogen, thin tungsten layers are shown to be pervious to atomic hydrogen, enabling atomic hydrogen to be diffused through a tungsten electrode into an underlying semiconductor-dielectric interface.
    Type: Grant
    Filed: March 20, 2003
    Date of Patent: October 12, 2004
    Assignee: International Business Machines Corporation
    Inventors: Paul M. Solomon, Douglas A. Buchanan, Eduard A. Cartier, Kathryn W. Guarini, Fenton R. McFeely, Huiling Shang, John J. Yourkas
  • Patent number: 6792173
    Abstract: Described is a device for directing an optical signal from a first optical fiber (101, 102, . . . ) along one of a plurality of selectable switching paths each terminating in a corresponding one of a plurality of second optical fibers (401, 402, . . . ) via an optical element (201, 202, . . . ), the optical element (201, 202, . . . ) being moveable by a controllable actuator (60) from a first to a second position to change the switching path of incident optical signal. The optical element (201, 202, . . . ) is slideably mounted in parallel to a first mounting plate (10) comprising a conduit (11) through which the optical signals from the first optical fiber (101, 102, . . . ) can be directed by the optical element (201, 202, . . . ) along the selected one of the switching paths to one of a plurality of conduits (21) in a second mounting plate (20) parallel to the first mounting plate (10), and further to the corresponding one of second optical fibers (401, 402, . . . ).
    Type: Grant
    Filed: May 13, 2002
    Date of Patent: September 14, 2004
    Assignee: International Business Machines Corporation
    Inventors: Gian-Luca Bona, Michel Despont
  • Patent number: 6782177
    Abstract: A method for manufacturing an optical device with a defined total device stress and a therefrom resulting defined birefringence and a therefrom resulting defined optical polarization dependence is disclosed. In a preferred embodiment, a lower cladding layer of an amorphous material with a first refractive index is provided and above that an upper cladding layer of an amorphous material with a second refractive index, which latter is manufactured from a material which is tunable in its stress. Between the lower and upper cladding layer an optical waveguide core is manufactured comprising an amorphous material having a third refractive index which is larger than the first and second refractive index. The optical waveguide core is thermally annealed, after which it has a defined waveguide core stress. The upper cladding layer is manufactured to have a cladding layer stress that together with the waveguide core stress results in the total device stress.
    Type: Grant
    Filed: May 7, 2002
    Date of Patent: August 24, 2004
    Assignee: International Business Machines Corporation
    Inventors: Gian-Luca Bona, Roland Germann, Ingmar Meijer, Bert Offrein, Huub L. Salemink, Dorothea W Wiesmann
  • Patent number: 6778431
    Abstract: A magnetic memory circuit comprises a plurality of memory cells and a plurality of bit lines coupled to the memory cells for selectively accessing one or more of the memory cells. The memory circuit comprises at least one bit line programming circuit, configurable as a current source for generating a programming current for writing a logical state of at least one memory cell and/or a current sink for returning the programming current, and a first set of switches. The first set of switches are disabled at least during a read operation of the memory cells and at least a portion of the first set of switches are selectively enabled during a write operation of the memory cells. Each switch in the first set of switches is configured to selectively couple the at least one bit line programming circuit to a corresponding one of the bit lines in response to a first control signal. The memory circuit further comprises at least one sense amplifier and a second set of switches.
    Type: Grant
    Filed: December 13, 2002
    Date of Patent: August 17, 2004
    Assignee: International Business Machines Corporation
    Inventors: Dietmar Gogl, William Robert Reohr, Roy Edwin Scheuerlein
  • Patent number: 6778429
    Abstract: A write circuit for selectively writing one or more magnetic memory cells in an MRAM includes at least one programmable current source being couplable to one or more global word lines in the MRAM, the programmable current source including an input for receiving a first control signal and an output, the programmable current source generating at least a portion of a write current at the output having a magnitude which varies in response to the first control signal. The write circuit further includes a plurality of current sinks, each current sink being couplable to one or more global word lines in the MRAM, each current sink including an input for receiving a second control signal, each current sink returning at least a portion of the write current in response to the second control signal.
    Type: Grant
    Filed: June 2, 2003
    Date of Patent: August 17, 2004
    Assignee: International Business Machines Corporation
    Inventors: Yu Lu, William Robert Reohr