Patents Assigned to STMicroelectronics, Inc.
  • Patent number: 5963485
    Abstract: A bit line recovery circuit for random access memory. The circuit includes a pair of pull-up devices, each of which is connected to a bit line of a bit line pair. Pass gates are disposed between a sense amplifier and the bit lines. The pull-up devices are cross-coupled such that the gate node of the pull-up devices are connected to the sense amplifier on the opposed side of the pass gates in order to rapidly turn on the appropriate pull-up device following a memory cell read operation.
    Type: Grant
    Filed: August 19, 1998
    Date of Patent: October 5, 1999
    Assignee: STMicroelectronics, Inc.
    Inventors: James Brady, James L. Worley
  • Patent number: 5960464
    Abstract: A method and apparatus employing a memory management system that can be used with applications requiring a large contiguous block of memory, such as video decompression techniques (e.g., MPEG 2 decoding). The system operates with a computer and the computer's operating system to request and employ approximately 500 4-kilobyte pages in two or more noncontiguous blocks of the main memory to construct a contiguous 2-megabyte block of memory. The system can employ, on a single chip, a direct memory access engine, a microcontroller, a small block of optional memory, and a video decoder circuit. The microcontroller retains the blocks of multiple pages of the main memory, and the page descriptors of these blocks, so as to lock down these blocks of memory and prohibit the operating system or other applications from using them. The microcontroller requests the page descriptors for each of the blocks, and programs a lookup table or memory mapping system in the on-chip memory to form a contiguous block of memory.
    Type: Grant
    Filed: August 23, 1996
    Date of Patent: September 28, 1999
    Assignee: STMicroelectronics, Inc.
    Inventor: Christopher S. Lam
  • Patent number: 5960311
    Abstract: A method of forming a thick interlevel dielectric layer containing sealed voids, formed in a controlled manner, over a substantially planar surface in semiconductor device structure, and the semiconductor structure formed according to such a method. The sealed voids are used to reduce interlevel capacitance. A plurality of metal signal lines are formed over a globally planarized insulator. A thick layer of first conformal interlevel dielectric is deposited over the metal signal lines and over the intermetal spacings formed between the metal signal lines. Because of the thickness, flow properties, and manner of deposition of the interlevel dielectric and the aspect ratio the intermetal spacings, voids are formed in the first conformal interlevel dielectric, in the intermetal spacings. This interlevel dielectric is then etched or polished back to the desired thickness, which exposes the voids in the wider intermetal spacings, but does not expose voids in the narrower intermetal spacings.
    Type: Grant
    Filed: August 14, 1997
    Date of Patent: September 28, 1999
    Assignee: STMicroelectronics, Inc.
    Inventors: Abha R. Singh, Artur P. Balasinski, Ming M. Li
  • Patent number: 5959910
    Abstract: A test mode of a memory device may be invoked that varies the sense amplifier clocking of the memory device as a function of manipulation of a control signal external to the memory device. At the appropriate logic state of a test mode enable signal, the test mode of the memory device is entered. Normal clocking of the sense amplifier is suspended during the test mode and the sense amplifier is clocked according to the transition of an external control signal from a first logic state to a second logic state. A predetermined period of time after the transition of the external control signal, the sense amplifier if clocked.
    Type: Grant
    Filed: April 25, 1997
    Date of Patent: September 28, 1999
    Assignee: STMicroelectronics, Inc.
    Inventor: David Charles McClure
  • Patent number: 5960277
    Abstract: A merged power device structure, of the emitter-switching type, in which the emitter of the bipolar power transistor has a minimum-width pattern which is aligned to the trenches of a trench control transistor. Thus the current density of the bipolar is maximized, since the emitter edge length per unit area is increased. The parasitic base resistance of the bipolar can also be reduced.
    Type: Grant
    Filed: June 4, 1997
    Date of Patent: September 28, 1999
    Assignee: STMicroelectronics, Inc.
    Inventor: Richard A. Blanchard
  • Patent number: 5956615
    Abstract: A method is provided for forming an improved landing pad of a semiconductor integrated circuit, and an integrated circuit formed according to the same. A first opening is formed through a first dielectric layer to expose a portion of a diffused region. A landing pad is formed over the first dielectric layer and in the opening. The landing pad preferably comprises a doped polysilicon layer disposed in the first opening and over a portion of the first dielectric layer. The landing pad will provide for smaller geometries and meet stringent design rules such as that for contact space to gate. A second dielectric layer having an opening therethrough is formed over the landing pad having an opening therethrough exposing a portion of the landing pad. A conductive contact, such as aluminum, is formed in the contact opening. The conductive contact will electrically connect with the diffused region through the landing pad.
    Type: Grant
    Filed: December 22, 1994
    Date of Patent: September 21, 1999
    Assignee: STMicroelectronics, Inc.
    Inventors: Loi N. Nguyen, Frank R. Bryant
  • Patent number: 5955770
    Abstract: A method is provided for forming a planar transistor of a semiconductor integrated circuit, and an integrated circuit formed according to the same. A plurality of field oxide regions are formed overlying a substrate electrically isolating a plurality of transistors encapsulated in a dielectric. LDD regions are formed in the substrate adjacent the transistors and the field oxide regions. Doped polysilicon raised source and drain regions are formed overlying the LDD regions and a tapered portion of the field oxide region and adjacent the transistor. These polysilicon raised source and drain regions will help to prevent any undesired amount of the substrate silicon from being consumed, reducing the possibility of junction leakage and punchthrough as well as providing a more planar surface for subsequent processing steps.
    Type: Grant
    Filed: June 18, 1997
    Date of Patent: September 21, 1999
    Assignee: STMicroelectronics, Inc.
    Inventors: Tsiu C. Chan, Gregory C. Smith
  • Patent number: 5955915
    Abstract: A current limiting circuit used with voltage regulators or other similar circuits is disclosed. The current limiting circuit uses two transistors, configured as a differential pair, combined with a fixed current source to limit the current available to a pass transistor of the voltage regulator.
    Type: Grant
    Filed: February 13, 1996
    Date of Patent: September 21, 1999
    Assignee: STMicroelectronics, Inc.
    Inventor: William Ernest Edwards
  • Patent number: 5952707
    Abstract: A semiconductor structure comprises a silicon substrate of a first conductivity type including wells of a second conductivity type disposed on a surface thereof and a dielectric layer including silicon nitride disposed on the surface. The dielectric layer includes openings at least partially disposed on the p-wells. The dielectric layer also includes a top layer comprising silicon dioxide having a thickness of less than ten angstroms. Trenches having a depth comparable to or greater than a depth of the wells extend into the substrate surface within the openings. A nonconductive material is disposed within the trenches and has an upper surface that is substantially coplanar with the dielectric layer. Portions of the dielectric layer are used as gate dielectrics for transistors.
    Type: Grant
    Filed: December 5, 1997
    Date of Patent: September 14, 1999
    Assignee: STMicroelectronics, Inc.
    Inventor: Robert Louis Hodges
  • Patent number: 5951690
    Abstract: A DVD player that integrates a DVD device into a personal computer is provided. As such, the personal computer is able to output audio-visual works from a DVD CD-ROM. When integrating a DVD device with a personal computer, various problems must be overcome. For example, in a personal computer, the video display is controlled by a graphics controller, and in order to render an audio-visual stream in a personal computer, the audio-visual stream and the graphics controller must be synchronized. The synchronization problem arises because the graphics controller only displays data at the beginning of 33.4 millisecond time intervals. Thus, although the audio portion may be played almost immediately, the video portion may have to wait for up to 33.4 milliseconds before being displayed. In this manner, the audio portion and the video portion become unsynchronized which means that the audio portion plays before the corresponding video portion is displayed.
    Type: Grant
    Filed: December 9, 1996
    Date of Patent: September 14, 1999
    Assignee: STMicroelectronics, Inc.
    Inventors: Yehuda Baron, Jefferson E. Owen, Darryn D. McDade
  • Patent number: 5952858
    Abstract: A method and structure for wave-shaping of digital waveforms of integrated circuit processes that do not have area efficient dielectric capacitors is disclosed. The dielectric capacitors of the prior art are replaced with a first, linearizing diode and a second diode of a wave-shaping circuit, each diode having a junction capacitance that varies with voltage applied across the diode. The first, linearizing diode is supplied with a constant current from a constant current source. A current inversely proportional to the junction capacitance of the first, linearizing diode is produced at a node defined as the connection between the constant current source and the first linearizing diode. The current at the node is supplied to the second diode to produce an output voltage of the wave-shaping circuit that is linear with respect to time.
    Type: Grant
    Filed: January 23, 1997
    Date of Patent: September 14, 1999
    Assignee: STMicroelectronics, Inc.
    Inventors: William Ernest Edwards, Joseph Notaro
  • Patent number: 5949720
    Abstract: A circuit for clamping the voltage appearing on the bit lines of a dynamic random access memory (DRAM) device so that the voltage thereon is maintained above the low reference voltage source. The circuit includes pull-up devices connected to the bit lines of the DRAM device. The pull-up devices are active only when pull-down devices connected to the bit lines pull some of the bit lines towards the low reference voltage level.
    Type: Grant
    Filed: October 30, 1998
    Date of Patent: September 7, 1999
    Assignee: STMicroelectronics, Inc.
    Inventor: James Brady
  • Patent number: 5949156
    Abstract: An integrated circuit capacitor ladder which uses a differential pair of capacitors for each step in the ladder. By pairing a square with a rectangle of equal perimeter, the contributions of edge and corner elements can be canceled out. This adds area and complexity, but greatly increases the precision of scaling.
    Type: Grant
    Filed: July 16, 1997
    Date of Patent: September 7, 1999
    Assignee: STMicroelectronics, Inc.
    Inventor: Robert Groover
  • Patent number: 5950072
    Abstract: An integrated circuit package had leadless solderballs attached to the substrate with a conductive thermoplastic adhesive. The leadless solderballs are preferably made with a copper-nickel-gold alloy. The conductive thermoplastic is preferably of the silver fill type. The integrated circuit package is placed in a frame and held to the printed circuit board with a clamp or with a screw.
    Type: Grant
    Filed: July 25, 1997
    Date of Patent: September 7, 1999
    Assignee: STMicroelectronics, Inc.
    Inventor: Daniel G. Queyssac
  • Patent number: 5945738
    Abstract: A method is provided for forming an improved landing pad of a semiconductor integrated circuit, and an integrated circuit formed according to the same. A first opening is formed through a first dielectric layer to expose a portion of a diffused region. A dual polysilicon landing pad is formed in the first opening and on a portion of the first dielectric layer adjacent the first opening. The dual landing pad is preferably formed from two polysilicon landing pads with an oxide formed in between a portion of the two polysilicon layers and over the first polysilicon layer. This landing pad will enhance the planarization of the wafer at this stage of the manufacturing and tolerate misalignment of subsequently formed metal contacts without invading design rules.
    Type: Grant
    Filed: December 3, 1996
    Date of Patent: August 31, 1999
    Assignee: STMicroelectronics, Inc.
    Inventors: Loi N. Nguyen, Frank R. Bryant, Artur P. Balasinski
  • Patent number: 5946264
    Abstract: A memory structure features a write driver circuit that is controlled to assist equilibrate devices recover one or more bitlines attached to a memory cell following the completion of a write operation of the memory cell. After the write operation, a write bus true and a write bus complement generated by the write driver are coupled to bitlines and equilibration devices by passgates controlled by a control signal.
    Type: Grant
    Filed: October 30, 1998
    Date of Patent: August 31, 1999
    Assignee: STMicroelectronics, Inc.
    Inventor: David Charles McClure
  • Patent number: 5945818
    Abstract: A voltage regulator with load pole stabilization is disclosed. An error amplifier has a non-inverting input receiving a reference voltage and an inverting input receiving a feedback voltage from the output of the voltage regulator. A gain stage has an input connected to the output of the error amplifier and an output connected to a pass transistor that provides current to a load. A variable impedance device such as a FET transistor configured as a variable resistor is connected between the input and output of the gain stage to provide variable zero to cancel the varying pole when the output current drawn by the load fluctuates. Consequently, the disclosed voltage regulator has high stability without a significant increase in power dissipation.
    Type: Grant
    Filed: June 16, 1998
    Date of Patent: August 31, 1999
    Assignee: STMicroelectronics, Inc.
    Inventor: William E. Edwards
  • Patent number: 5943598
    Abstract: A method of forming a portion of a semiconductor integrated circuit having a semiconductor substrate as well as the resulting integrated circuit. In the inventive method, various steps are involved. In one embodiment, for example, the method steps are as follows. First, there is formed a first polysilicon layer overlying and in contact with the semiconductor substrate. Second, a plurality of conductive structures are patterned from the first polysilicon layer. Third, there is formed a dielectric layer having an upper planar surface and having a lower surface contacting the semiconductor substrate and the plurality of conductive structures from the first polysilicon layer. Fourth, there is formed a second polysilicon layer overlying and in contact with the dielectric layer. Fifth, a plurality of conductive structures are formed from the second polysilicon layer. Lastly, there is formed a metallic layer over the plurality of conductive structures from the second polysilicon layer.
    Type: Grant
    Filed: October 19, 1995
    Date of Patent: August 24, 1999
    Assignee: STMicroelectronics, Inc.
    Inventor: Yih-Shung Lin
  • Patent number: RE36292
    Abstract: The device comprises a first chain of scanning cells located at the stimulation input of each respective functional block of the integrated circuit and a second chain of scanning cells located at the assessment output of each respective functional block of the integrated circuit. Each cell comprises a master part, a slave part and switching circuit to alternately enable the master and slave parts under the control of respective master clock and slave clock signals coincident with opposite phases of a scanning clock signal having a substantially square wave. With each pair of chains of scanning cells there are associated clock generators to locally obtain the master and slave clocks from the scanning clock.
    Type: Grant
    Filed: June 23, 1997
    Date of Patent: September 7, 1999
    Assignee: STMicroelectronics, Inc.
    Inventors: Flavio Scarra, Maurizio Gaibotti
  • Patent number: RE36319
    Abstract: According to the present invention, a structure for holding broken select lines in a memory array deselected addresses the prior art problems associated with floating broken select lines, such as standby current and disruption of attached memory cells. The structure is a high impedance device which is placed on the end of select lines so that if a select line is broken during fabrication, the high impedance device, will hold the broken end of the select line to the desired deselect voltage. Select lines which have a driver at one end only and are broken during fabrication, but have the high impedance device on the other end, are not allowed to float. The high impedance device is also suitable for select lines which are not broken and previously were anchored at just one end. Suitable high impedance devices include a reverse biased diode, a weak transistor, a poly R memory cell load device, and an ON or OFF TFT memory cell load device.
    Type: Grant
    Filed: November 7, 1997
    Date of Patent: September 28, 1999
    Assignee: STMicroelectronics, Inc.
    Inventor: William C. Slemmer