Patents Assigned to VLSI Technology
  • Patent number: 5610105
    Abstract: An improved anneal process is disclosed for use in the preparation of a dielectric layer, especially an intermetal dielectric layer. An oxide layer is deposited using a H.sub.2 O-TEOS PECVD process. A vacuum bake is used to minimize or eliminate volatile water, hydrogen, and hydrocarbon impurities in the dielectric layer. An oxidation anneal is then performed to scavenge any remaining undesirable species, and to provide for densification of the dielectric layer.
    Type: Grant
    Filed: June 10, 1994
    Date of Patent: March 11, 1997
    Assignee: VLSI Technology, Inc.
    Inventors: Landon B. Vines, Sigmund A. Koenigseder, John L. Cain, Chang-Ou Lee, Felix Fujishiro
  • Patent number: 5610417
    Abstract: A method for making an integrated circuit characterized by: determining a range of bonding pad pitches which varies between a minimum bonding pad pitch and a maximum bonding pad pitch; setting a driver pitch to the minimum bonding pad pitch; forming a base set including a plurality of drivers having the determined driver pitch; forming customization layers over the base set, where the customization layers include a plurality of bonding pads having a pad pitch greater than the minimum bonding pad pitch but less than or equal to the maximum bonding pad pitch; and coupling some, but not all, of the drivers to the pads. As a result, a single base set can be used to make integrated circuits having a range of bonding pad pitches. The method and structure of the present invention are very well adapted for use in gate array integrated circuits.
    Type: Grant
    Filed: April 3, 1995
    Date of Patent: March 11, 1997
    Assignee: VLSI Technology, Inc.
    Inventor: Bryan C. Doi
  • Patent number: 5608357
    Abstract: A data retiming system for retiming incoming data and eliminating jitter is described. The data retiming system includes a local clock; a phase aligner for receiving the incoming data and producing a recovered clock from the incoming data, and then producing retimed incoming data by retiming the incoming data with the recovered clock; and a buffer memory for removing jitter from the retimed incoming data by storing the retimed incoming data to the buffer memory in accordance with the recovered clock and reading the stored data from the buffer memory in accordance with the local clock. The data retiming system provides reliable operation even at very high data rates. A freezeable voltage-controlled oscillator for producing a clock signal in accordance with a freeze signal and a frequency control signal is also disclosed. Using current steering techniques, the freezeable voltage-controlled oscillator is able to freeze its output very quickly.
    Type: Grant
    Filed: September 12, 1995
    Date of Patent: March 4, 1997
    Assignee: VLSI Technology, Inc.
    Inventors: Paul Ta, Michael Cheng
  • Patent number: 5608645
    Abstract: The present invention is directed to a method of designing and fabricating a circuit layout which revolutionizes the manner by which critical weights of a circuit layout are assessed. In accordance with exemplary embodiments, a critical path is assessed on the basis of both a physical delay associated with a data propagation path and with respect to any clock skew which exists with respect to the data propagation path. A critical path can be a path having the shortest physical length from an input node to an output node if the clock skew along this path results in a high probability of a race condition. In accordance with exemplary embodiments, clock skew is assessed by determining the time differential between the arrival of a clock signal at a given data source instance and the arrival of a clock signal at a given data destination instance.
    Type: Grant
    Filed: March 17, 1994
    Date of Patent: March 4, 1997
    Assignee: VLSI Technology, Inc.
    Inventor: Athanasius W. Spyrou
  • Patent number: 5608734
    Abstract: A method and apparatus for framing data in digital transmission lines automatically recognizes a framing format. The apparatus preferably includes a frame alignment apparatus that can recognize any one of a number of predetermined framing formats created by framing information on an input signal. The frame alignment apparatus outputs an aligning signal to an output frame counter, which counts the data and framing information on the input signal and outputs a frame synchronization signal according to the framing format. The input signal is also coupled to an output apparatus that outputs the input signal at the clock rate of a terminating apparatus. The frame alignment apparatus preferably includes a plurality of pattern recognizers able to recognize at least one of the framing formats and a storage apparatus for storing counts of successive data and framing information that match a framing pattern. The counts are preferably used to identify the framing information on the input signal and the framing format.
    Type: Grant
    Filed: November 20, 1995
    Date of Patent: March 4, 1997
    Assignee: VLSI Technology, Inc.
    Inventors: Lorin H. Sandler, Neal T. Wingen
  • Patent number: 5605454
    Abstract: A quartz tube with multiple thermocouple ports arranged along its radius allows for the quartz tube to be rotated while the thermocouple is always placed in the bottom position of the quartz tube. This avoids a problem of the sagging of the quartz tube. When quartz tubes are not rotated, the quartz tubes tend to start sagging from their top. By rotating the quartz tube different portions of the quartz tube are at the top at different times. By using multiple thermocouple ports arranged around the radius of the quartz tube, the thermocouple can be positioned at the bottom of the quartz tube for different orientations of the quartz tube.
    Type: Grant
    Filed: October 12, 1995
    Date of Patent: February 25, 1997
    Assignee: VLSI Technology, Inc.
    Inventors: Craig A. Bellows, Curtis M. Herbert, Jr.
  • Patent number: 5604750
    Abstract: A method for improving the setup time of an integrated circuit tester when a device under test is to be tested includes maintaining the voltage settings for supply voltage (Vdd), voltage input low level (VIL), voltage output low level (VOL), voltage input high level (VIH), and voltage output high level (VOH) in a DRAM memory in the tester. Consequently, the tester data base keeps the image of the last hardware setup, which was used to operate a test sequence on a device under test (DUT). To reduce the time for effecting an integrated circuit test on a new test, the software code for the new test compares the various voltage settings for the new test with the stored voltage settings for the last hardware setup. No hardware operating changes are made whenever the compared voltage settings agree; and only voltage settings which are incorrect are changed in the hardware in a sequential comparison of the various voltages. This software check and comparison takes place in micro-seconds or nanoseconds.
    Type: Grant
    Filed: November 1, 1994
    Date of Patent: February 18, 1997
    Assignee: VLSI Technology, Inc.
    Inventor: Paul S. Levy
  • Patent number: 5604689
    Abstract: An arithmetic logic unit provides for zero-result prediction so as to eliminate the latency between successive operations (e.g., multiplication and division) when a zero detection is a condition for performance of the second operation. Instead of performing zero detection on the result, zero prediction is performed on the initial or intermediate operands, (e.g., partial products that are summed to generate a product). To this end, zero-prediction logic determines whether or not both of the following conditions are met: 1) either the least significant bits of the addends are the same and the carry-in is zero or the least significant bits of the addends are different and the carry-in is one. 2) for each pair of adjacent bit positions, the four included bits are consistent with addend complementarity. If both conditions are met, a zero result is predicted; otherwise, a non-zero result is predicted.
    Type: Grant
    Filed: May 24, 1996
    Date of Patent: February 18, 1997
    Assignee: VLSI Technology, Inc.
    Inventor: Kenneth A. Dockser
  • Patent number: 5604694
    Abstract: An improved charge pump circuit uses standard low-voltage fabrication process for programming an anti-fuse memory cell from a high-voltage current source. A column-selection transistor which has a gate terminal connected to a control terminal. The column-select transistor is connected between a high voltage programming current source and one terminal of an anti-fuse link. The other terminal of the anti-fuse link is connected through a word-selection transistor to ground. The gate terminal of the word-selection transistor is connected to a word selection line. Two oppositely phased charge pumps provide a boosted voltage. A trapping-diode-connected transistor isolates the boosted voltage from the gate terminal of the column-selection transistor. A charge-kicker circuit further boosts the voltage on the gate of the column-selection transistor to turn on and pass current from the high voltage programming current source through the anti-fuse link.
    Type: Grant
    Filed: January 16, 1996
    Date of Patent: February 18, 1997
    Assignee: VLSI Technology, Inc.
    Inventor: John Callahan
  • Patent number: 5602056
    Abstract: The invention relates to MOS devices and methods for fabricating MOS devices having multilayer metallization. In accordance with preferred embodiments, internal passivation is used for suppressing device degradation from internal sources. Preferred devices and methods for fabricating such devices include formation of one or more oxide layers which are enriched with silicon to provide such an internal passivation and improve hot carrier lifetime. Preferred methods for fabricating MOS devices having multi-level metallization include modifying the composition of a PECVD oxide film and, in some embodiments, the location and thickness of such an oxide. In an exemplary preferred embodiment, PECVD oxide layers are modified by changing a composition to a silicon enriched oxide.
    Type: Grant
    Filed: May 4, 1995
    Date of Patent: February 11, 1997
    Assignee: VLSI Technology, Inc.
    Inventors: Vivek Jain, Dipankar Pramanik, Subhash R. Nariani, Kuang-Yeh Chang
  • Patent number: 5603045
    Abstract: A Harvard architecture data processing system includes a processor, main memory, an instruction cache, and a data cache. As is generally known with the Harvard architecture, these components are interconnected by an instruction bus, an instruction address bus, a data bus, and a data address bus. The instruction cache includes a branch target section and a general instruction section. For each instruction request by the processor, both sections are examined to determine if the requested instruction is in the cache. If it is, it is transmitted from the cache to the processor. If it is not, an instruction line including the requested instruction is fetched from main memory. If the requested instruction represents a jump (the result of an unconditional branch or a conditional branch the condition of which is met) the fetched instruction line can be stored only in the branch target section.
    Type: Grant
    Filed: December 16, 1994
    Date of Patent: February 11, 1997
    Assignee: VLSI Technology, Inc.
    Inventor: Kenneth A. Dockser
  • Patent number: 5603055
    Abstract: A shared keyboard and system ROM uses a single ROM for both the keyboard and the system operating system information (BIOS). The shared ROM is never simultaneously used for both of these functions. At initial boot-up, the system processor executes from the shared ROM to copy the system BIOS information to the system Random Access Memory DRAM. Once this copying has been completed, the shared ROM then is used by the keyboard subsystem. Different address ranges are employed in the shared ROM for the keyboard information and for the system BIOS.
    Type: Grant
    Filed: January 27, 1994
    Date of Patent: February 11, 1997
    Assignee: VLSI Technology, Inc.
    Inventors: David R. Evoy, Lawrence D. Gould, James R. Edwards, Donald G. Scharnberg, Doyne L. Metz
  • Patent number: 5598120
    Abstract: A digital integrated circuit provided with a dual latch clocked LSSD that includes a master latch coupled to a slave latch such that it operates in at least three operational modes. Preferably the three modes of the dual latch clocked LSSD include a functional mode, a capture mode, and a shift mode. In the functional mode, the dual latch clocked LSSD operates as an edge-triggered flip-flop storage element. In the capture mode, the dual latch clocked LSSD operates as a level sensitive latch storage element controlled by the system clock, one of two scan clock signals, and, preferably, by a test mode input signal. In the shift mode, the dual latch clocked LSSD again operates as a level sensitive latch storage element, but is controlled by a pair of shift clocks. By separating the capture mode from the functional mode, the dual latch clocked LSSD is exceptionally resistant to skew problems in both the capture and the shift modes.
    Type: Grant
    Filed: July 17, 1995
    Date of Patent: January 28, 1997
    Assignee: VLSI Technology, Inc.
    Inventor: Stephen A. Yurash
  • Patent number: 5598446
    Abstract: A clock signal is extracted from a received signal. An edge detector detects edges of the received signal, where the received signal transitions between a logic 0 and a logic 1. A center between each pair of consecutive edges is determined. An extracted clock signal is generated. The phase of the extracted clock signal is varied based on the center between each pair of consecutive edges. For example, the center between each pair of consecutive edges is determined by counting a number of cycles of an over sampling signal which occurs between each pair of consecutive edges to obtain a bit width. The bit width is divided in half and the result added to an edge phase value to obtain a value for the center. Also, the phase of the extracted clock signal may be varied based on the center between each pair of consecutive edges as follows. An amount a plurality of centers varies from a center of the extracted clock signal is averaged to produce a phase error.
    Type: Grant
    Filed: September 8, 1995
    Date of Patent: January 28, 1997
    Assignee: VLSI Technology, Inc.
    Inventor: Roland M. M. H. Van Der Tuijn
  • Patent number: 5598031
    Abstract: An integrated-circuit package assembly includes a separate silicon substrate to which an integrated-circuit die is fixed. The separate silicon substrate serves as a heat spreader for the integrated-circuit die. The separate silicon substrate to which the integrated-circuit die is fixed is packaged in either a molded package body or a cavity-type package body. For the molded package body, the package body is molded around a leadframe, the integrated-circuit die, and the separate silicon substrate to which the integrated-circuit die is fixed. For a molded package body, the leadframe has bonding fingers formed at the inward ends thereof which are attached to the separate silicon substrate or the lead frame may have a die-attach pad to which is fixed the separate silicon substrate. For the cavity-type package, the package body includes a mounting surface formed adjacent to a cavity formed therein and the mounting surface has the separate silicon substrate fixed to the top surface thereof.
    Type: Grant
    Filed: October 25, 1994
    Date of Patent: January 28, 1997
    Assignee: VLSI Technology, Inc.
    Inventors: Richard L. Groover, William K. Shu, Sang S. Lee, George Fujimoto
  • Patent number: 5597668
    Abstract: The planarity of the dielectric layer over a processing layer is increased by adjustments made to a mask generated for patterning the processing layer. Active circuitry lines are generated for the mask. Also, a fill pattern is generated for the mask. The fill pattern is placed in areas of the mask not filled by the active circuitry lines. The active circuitry lines are combined with the fill pattern to produce a final pattern for the mask. In one embodiment, the fill pattern is generated by first over-sizing the active circuitry lines to form a first pattern. The first pattern is inverted to produce a negative of the first pattern. The negative of the first pattern serves as a marker layer. In addition, a dummy fill pattern is generated. An intersection of the marker layer and the dummy fill pattern is performed to produce an unsized fill pattern.
    Type: Grant
    Filed: July 19, 1995
    Date of Patent: January 28, 1997
    Assignee: VLSI Technology, Inc.
    Inventors: Edward D. Nowak, Subhas Bothra, David Eatock, Wesley Erck
  • Patent number: 5596288
    Abstract: A single bit status register includes an input flip-flop, an asynchronous latch having an input coupled to an output of the input flip-flop, a comparator for comparing the outputs of the flip-flop and the latch, and an output stage which provides an error output when the comparator determines that the outputs of the flip-flop and the latch are not the same. In this fashion, it is known when a "read" of the status register is invalid due to the presence of the error output. Preferably, the register also includes a reset disabling mechanism which prevents the input flip-flop from being reset until a valid read has occurred. A n-bit status register includes n register sections, where each register section includes an input flip-flop, an asynchronous latch having an input coupled to an output of the input flip-flop, and a register section comparison mechanism for comparing the outputs of the flip-flop and the latch in that register section.
    Type: Grant
    Filed: September 7, 1995
    Date of Patent: January 21, 1997
    Assignee: VLSI Technology, Inc.
    Inventors: Laura E. Simmons, Joseph A. Thomsen
  • Patent number: 5596505
    Abstract: A method for producing an electrical circuit by determining the input-to-output timing of compiled circuit blocks includes steps of determining a signal delay of a component due to physical characteristics of the component. The physical characteristics include at least a capacitance based upon relative placement of the component during compilation of a circuit block. The method further includes steps of determining an input-to-output speed for a circuit block by combining delays due to physical characteristics through alternate paths of the circuit block, and producing a compiled circuit block having a plurality of components by placing the components in the circuit block based on the steps of determining.
    Type: Grant
    Filed: July 23, 1993
    Date of Patent: January 21, 1997
    Assignee: VLSI Technology, Inc.
    Inventors: Russell L. Steinweg, Michael A. Zampaglione, Pei H. Lin
  • Patent number: 5594445
    Abstract: An interstage amplifier for a pipelined analog to digital converter comprises an operational amplifier (50) having a first pair of capacitors (55,58), a second pair of capacitors (56,57), and switching means (59-62) connected to the capacitors and amplifier. The switching means interchanges the capacitor connections to compensate for offset in the amplifier. The arrangement provides first-order correction of capacitor mismatch.
    Type: Grant
    Filed: July 20, 1995
    Date of Patent: January 14, 1997
    Assignee: VLSI Technology, Inc.
    Inventor: Bernard Ginetti
  • Patent number: 5587332
    Abstract: The present invention relates to a flash EEPROM cell using polysilicon-to-polysilicon hot electron emission to erase the memory contents of the cell. Exemplary embodiments include a side gate, a control gate, a floating gate and source and drain regions. Appropriate biasing of these gates and source and drain regions controls the electron population of the floating gate. The memory cells may be of either the double polysilicon or triple polysilicon variety. Peripheral transistors are formed from a last formed polysilicon layer to avoid degrading the peripheral transistors.
    Type: Grant
    Filed: September 1, 1992
    Date of Patent: December 24, 1996
    Assignee: VLSI Technology, Inc.
    Inventors: Kuang-Yeh Chang, Subhash R. Nariani, William J. Boardman