Patents Represented by Attorney Angus Fox
  • Patent number: 4962326
    Abstract: I/O lines on a CMOS circuit are precharged to preferred voltage levels in order to avoid latch up. The precharging is achieved by using N channel transistors to provide a precharge which is at a threshold voltage (V.sub.T) below bias voltage V.sub.CC, or (V.sub.CC -V.sub.T). This results in a lower forward bias when V.sub.CC bumps down after the I/O lines are floated. By lowering the precharge voltage by a level corresponding to a threshold voltage (V.sub.T), the allowed range of power supply voltage bumping is increased by this amount. This eliminmates the destructive effect of a negative bump of V.sub.BE, which would have presented a diode forward bias condition. Instead, the power supply may bump to (V.sub.BE +V.sub.T).
    Type: Grant
    Filed: July 22, 1988
    Date of Patent: October 9, 1990
    Assignee: Micron Technology, Inc.
    Inventors: Ward D. Parkinson, Wen-Foo Chern
  • Patent number: 4942576
    Abstract: Apparatus for comparing outputs of two digital devices and counting digital aberrations between them. One embodiment of this invention is the use of an XOR gate to compare the output of a DRAM under test to the output of a known good DRAM of corresponding operating characteristics, and the use of a counter to count the digital aberrations, known as badbits, between the two DRAMs.
    Type: Grant
    Filed: October 24, 1988
    Date of Patent: July 17, 1990
    Assignee: Micron Technology, Inc.
    Inventors: Jon P. Busack, Gary M. Johnson, Richard R. Clem
  • Patent number: 4915597
    Abstract: Valve and channeling improvements in a filter pump head assembly used for dispensing photoresist in a semiconductor manufacturing facility.
    Type: Grant
    Filed: December 19, 1988
    Date of Patent: April 10, 1990
    Assignee: Micron Technology, Inc.
    Inventor: Scott E. Moore
  • Patent number: 4897568
    Abstract: A pumpdown circuit uses voltage sensing to bring a low node to a potential of V.sub.SS +V.sub.T by first grounding the node and then floating the node to the V.sub.SS +V.sub.T potential. When a sensing node is at the V.sub.SS +V.sub.T potential, the sensing node is maintained at a level above ground by leakage current through a pump-up circuit. Biasing the digit and digit* lines to a potential V.sub.T above ground reduces current (amperage) requirement, because the digit and digit* lines do not have to be discharged completely to ground. The momentary discharge of the sense amp node to ground allows the sense amp to behave like a conventional sense amp during initial sensing, thereby allowing a minimum digit/digit* sensing potential to approximate ground plus V.sub.T.
    Type: Grant
    Filed: September 30, 1988
    Date of Patent: January 30, 1990
    Assignee: Micron Technology, Inc.
    Inventors: Wen-Foo Chern, Ward D. Parkinson, Zhitong Chen, Gary M. Johnson, Tyler A. Lowrey, Thomas M. Trent
  • Patent number: 4891794
    Abstract: A three port memory device has two serial ports and a random access memory port. The random access memory port is addressed to a random access memory in a conventional manner, using RAS and CAS address signals. Data may also be supplied and retrieved through two serial ports to a pair of serial access memories for transfer between the serial ports and the random access memory. This configuration permits formatted data to be simultaneously assessed through the two serial ports, while the random access memory port is being accessed.
    Type: Grant
    Filed: June 20, 1988
    Date of Patent: January 2, 1990
    Assignee: Micron Technology, Inc.
    Inventors: Glen E. Hush, Jeffrey S. Mailloux, Eugene H. Cloud
  • Patent number: 4882028
    Abstract: An R-F electrode apparatus is provided featuring self-adjusting, spring biased electrodes, removably attached to a removable substrate holder, within a chamber used for plasma reactive treatment processes, particularly those involving semiconductor wafers. The apparatus further features base electrodes shaped and supported to insure uniform transmission of electrical energy during operation. The apparatus also provides an automatic means for wiping, self-cleaning action between the contact surfaces of opposing electrodes during introduction and removal of the substrate holder from the reaction chamber. The base electrodes are removably attached to standard electrical feedthroughs located in the reaction chamber wall, which lead to an external R-F power supply.
    Type: Grant
    Filed: January 22, 1988
    Date of Patent: November 21, 1989
    Assignee: Micron Technology, Inc.
    Inventor: Navjot Chhabra
  • Patent number: 4882700
    Abstract: A printed circuit board is designed to conform to a single in-line memory module (SIMM) configuration, but includes multiple rows of the memory devices. By controlling a sequence of enable signals, selection of a single row from the multiple row of memory devices can be accomplished. The ability to address the different rows multiplies the memory capacity of the board by the number of rows of memory devices.
    Type: Grant
    Filed: June 8, 1988
    Date of Patent: November 21, 1989
    Assignee: Micron Technology, Inc.
    Inventors: Karl H. Mauritz, Geary L. Leger, Joseph B. Wicklund, James E. Herrud, Steven H. Laney
  • Patent number: 4872356
    Abstract: Apparatus to enclose a resistivity probe, to be used with a semiconductor wafer washer. Said apparatus is detachable and easy to maintain; is made of readily available and inexpensive plumbing parts; substantially encloses said probe, reducing contamination; allows nitrogen purge of said probe, keeping it clean; fully submerges said probe in discharge fluid, improving measurement accuracy; and is compact enough to allow washers to be triple stacked.
    Type: Grant
    Filed: December 27, 1988
    Date of Patent: October 10, 1989
    Assignee: Micron Technology Inc.
    Inventors: Jay D. Barnett, Bryan J. Ludwig, Ernest E. Marks, Scott E. Moore
  • Patent number: 4871688
    Abstract: A semiconductor memory device such as a dymanic random access memory (DRAM) is formed by first forming a burried contact in a silicon wafer and patterning a series of transistors. After the transistors are patterned, oxide layers are applied and the transistors are etched. Cell bottom plates are then formed and electrical connections between the transistors and a periphery are established. The establishment of the transistors are to forming the cell bottom plates and its more efficient manufacture of the DRAM devices and increases manufacturing yield.
    Type: Grant
    Filed: May 2, 1988
    Date of Patent: October 3, 1989
    Assignee: Micron Technology, Inc.
    Inventor: Tyler A. Lowrey
  • Patent number: 4859304
    Abstract: A plasma dry etch chamber is provided with an anode plate which has a cooling jacket which extends radially outwardly from a cooling core to an extent corresponding to the radial dimension of a silicon wafer work product. In order to further reduce deposit formation, the outer perimeter of the anode is designed to reduce the effects of polymer deposition.
    Type: Grant
    Filed: July 18, 1988
    Date of Patent: August 22, 1989
    Assignee: Micron Technology, Inc.
    Inventors: David A. Cathey, John C. Freeman, James Dale, William J. Crane, Eric A. Powell, Jeffrey V. Musser
  • Patent number: 4839301
    Abstract: A CMOS transistor is fasbricated by forming the n-wells with both phosphorus and arsenic implants. The arsenic, with its lower diffusion coefficient, tends to concentrate near the top surface of the n-wells, with the phosphorus penetrating sufficiently to define the n-wells at the desired depth. A boron channel stop implant is later applied without masking over the n-wells. Since the arsenic implant is concentrated near the surface, the arsenic impurities overcome the effects of the boron impurities. Additional boron required for n-channel channel stop is provided by n-channel transistor punch-through implantation.
    Type: Grant
    Filed: December 19, 1988
    Date of Patent: June 13, 1989
    Assignee: Micron Technology, Inc.
    Inventor: Ruojia R. Lee