Patents Represented by Attorney, Agent or Law Firm H. Daniel Schurmann
  • Patent number: 7810062
    Abstract: A method for eliminating negative slack in a netlist representing a chip design uses a contrived timing environment to overlay information onto the design environment during logic and physical synthesis phase. The overlaid timing information determines which netlist transformation provides a maximum leverage for the negative slack elimination and a way for creating a dynamic transformation recipe tuned for each design. The method further provides upper bounds on the negative slack elimination to prevent the netlist transforms from being applied to situations exceeding the capabilities for improving the design.
    Type: Grant
    Filed: September 11, 2007
    Date of Patent: October 5, 2010
    Assignee: International Business Machines Corporation
    Inventors: James J. Curtin, William E. Dougherty, Jr., Jose L. Neves, Douglas S. Search
  • Patent number: 7397261
    Abstract: A universal leakage monitoring system (ULMS) to measure a plurality of leakage macros during the development of a manufacturing process or a normal operation period. The ULMS characterizes the leakage of both n-type and p-type CMOS devices on the gate dielectric leakage, the sub-threshold leakage, and the reverse biased junction leakage, and the like. Testing is performed sequentially from the first test macro up to the last test macro using an on-chip algorithm. When the last test macro is tested, it scans the leakage data out.
    Type: Grant
    Filed: April 27, 2006
    Date of Patent: July 8, 2008
    Assignee: International Business Machines Corporation
    Inventors: Louis Lu-Chen Hsu, Edward R. Pillai, Joseph Natonio, James D. Rockrohr, David R. Hanson
  • Patent number: 7296251
    Abstract: Voltage islands enable a core-level power optimization of ASIC/SoC designs by utilizing a unique supply voltage for each cluster of the design. Creating voltage islands in a chip design for optimizing the overall power consumption consists of generating voltage island partitions, assigning voltage levels and floorplanning. The generation of voltage island partitions and the voltage level assignment are performed simultaneously in a floorplanning context due to the physical constraints involved. This leads to a floorplanning formulation that differs from the conventional floorplanning for ASIC designs. Such a formulation of a physically aware voltage island partitioning and method for performing simultaneous voltage island partitioning, level assignment and floorplanning are described, as are the definition and the solution of floorplanning for voltage island based designs executed under area, power, timing and physical constraints.
    Type: Grant
    Filed: May 25, 2004
    Date of Patent: November 13, 2007
    Assignee: International Business Machines Corporation
    Inventors: Nagashyamala R. Dhanwada, Youngsoo Shin, Jingcao Hu
  • Patent number: 6511791
    Abstract: A method for exposing a workpiece in a dual exposure step-and-repeat process starts by forming a design for a reticle mask. Deconstruct the design for the reticle mask by removing a set(s) of the features that are juxtaposed to form hollow polygonally-shaped clusters with a gap in the center. Form unexposed resist on the workpiece. Load the workpiece and the reticle mask into the stepper. Expose the workpiece through the reticle mask. Reposition the workpiece by a nanostep. Then expose the workpiece through the reticle mask after the repositioning. Test whether the plural exposure process is finished. If the result of the test is NO the process loops back to repeat some of the above steps. Otherwise the process has been completed. An overlay mark is produced by plural exposures of a single mark. A dead zone is provided surrounding an array region in which printing occurs subsequent to exposure in an original exposure.
    Type: Grant
    Filed: April 28, 2000
    Date of Patent: January 28, 2003
    Assignees: International Business machines Corporation, Infineon Technologies North American Corp.
    Inventors: Scott J. Bukofsky, Gerhard Kunkel, Richard Wise, Alfred K. Wong
  • Patent number: 6242923
    Abstract: A method of locating in a non-destructive and non-invasive manner power plane-to-power plane shorts or I/O net-to-power plane shorts found in a printed circuit board or a multi-chip-module by way of a magnetic field generating probe is described. Thousands of nets can be simultaneously tested to detect not only the presence of a short but also to accurately pinpoint its position. For high resistance shorts, the probe is provided with a pot core housed inductor located at its tip, and is used at low frequencies to minimize the effect of the capacitive impedance between the power planes. For low resistance shorts, the probe is used at high frequencies, delivering equal but opposite current to each of two matched inductors at the tip of the probe to maximize mutual inductive coupling while minimizing electrostatic capacitive coupling with the board or module. In both cases, the highest current stress is on the probe rather than on the expensive and fragile package under inspection.
    Type: Grant
    Filed: July 16, 1998
    Date of Patent: June 5, 2001
    Assignee: International Business Machines Corporation
    Inventors: Michael E. Scaman, Edward J. Yarmchuk, Arnold Halperin
  • Patent number: 6214647
    Abstract: A method and structure for thermally connecting a thermal conductor to at least one chip, the thermal conductor including a lower surface and at least one piston extending from the lower surface corresponding to each of the chips, each of the chips having an upper surface opposing each of the pistons, the chips being mounted on a substrate, the method comprising steps of metalizing the lower surface of the thermal conductor and the pistons, applying a solder to the lower surface of the thermal conductor, applying a thermal paste between the upper surface of the chips and the pistons, positioning the substrate and the thermal conductor such that the substrate is aligned with the thermal conductor, biasing the thermal conductor toward the substrate, biasing the pistons toward the chips such that the thermal paste has a consistent thickness between each of the chips and the pistons, reflowing the solder, such that the solder bonds the substrate to the thermal conductor and the pistons form a metallurgical bond w
    Type: Grant
    Filed: September 23, 1998
    Date of Patent: April 10, 2001
    Assignee: International Business Machines Corporation
    Inventors: Giulio Di Giacomo, Stephen S. Drofitz, Jr., David L. Edwards, Sushumna Iruvanti, David J. Womac
  • Patent number: 6081910
    Abstract: A circuit that enhances the testability of an integrated circuit of a memory type and which identifies defective redundant word lines in a state of the art SRAM macro that combines an ABIST structure with a redundancy mechanism. The circuit allows a two-pass fuse blow after completing the burn-in process that significantly increases the manufacturing yield and repairability of the SRAM macro.
    Type: Grant
    Filed: April 4, 1994
    Date of Patent: June 27, 2000
    Assignee: International Business Machines Corporation
    Inventors: Jean-Paul Mifsud, Stuart Rapoport
  • Patent number: 5831913
    Abstract: A method of making a memory fault-tolerant through the use of a variable size redundancy replacement (VSRR) circuit arrangement. A redundancy array supporting the primary arrays forming the memory includes a plurality of variable size redundancy units, each of which encompassing a plurality of redundant elements. The redundant units used for repairing faults in the memory are independently controlled. All the redundancy elements within a repair unit are preferably replaced simultaneously. The redundancy elements in the redundancy unit are controlled by decoding address lines. The variable size that characterizes this configuration makes it possible to choose the most effective redundancy unit, and in particular, the one most closely fitting the size of the cluster of failures to be replaced. This method significantly reduces the overhead created by added redundancy elements and control circuitry, while improving the access speed and reducing power consumption.
    Type: Grant
    Filed: March 31, 1997
    Date of Patent: November 3, 1998
    Assignee: International Business Machines Corporation
    Inventor: Toshiaki Kirihata