Patents by Inventor Irfan Rahim

Irfan Rahim has filed for patents to protect the following inventions. This listing includes patent applications that are pending as well as patents that have already been granted by the United States Patent and Trademark Office (USPTO).

  • Patent number: 6933591
    Abstract: Programmable fuses for integrated circuits are provided. The fuses may be based on polysilicon or crystalline silicon fuse links coated with silicide or other conductive thin films. Fuses may be formed on silicon-on-insulator (SOI) substrates. A fuse may be blown by applying a programming current to the fuse link. The silicon or polysilicon in the fuses may be provided with a p-n junction. When a fuse is programmed, the silicide or other conductive film forms an open circuit. This forces current though the underlying p-n junction. Unlike conventional silicided polysilicon fuses, fuses with p-n junctions change their qualitative behavior when programmed. Unprogrammed fuses behave like resistors, while programmed fuses behave like diodes. The presence of the p-n junction allows sensing circuitry to determine in a highly accurate qualitative fashion whether a given fuse has been programmed.
    Type: Grant
    Filed: October 16, 2003
    Date of Patent: August 23, 2005
    Assignee: Altera Corporation
    Inventors: Lakhbeer S. Sidhu, Irfan Rahim
  • Patent number: 6773987
    Abstract: A method of fabricating a non-volatile memory cell on a semiconductor substrate is disclosed. An area of a first region of the semiconductor substrate designated for a layer of floating polysilicon is blocked while a second region of the semiconductor substrate designated for a layer of non-floating polysilicon is exposed. Exposed regions of the semiconductor substrate are doped with charges.
    Type: Grant
    Filed: May 28, 2002
    Date of Patent: August 10, 2004
    Assignee: Altera Corporation
    Inventors: Irfan Rahim, Fangyun Richter
  • Patent number: 6670676
    Abstract: An apparatus comprising a first circuit. The first circuit may be configured to limit conduction between a first and a second power supply pin in response to one or more control signals. One or more of a plurality of paths may limit the conduction in response to one or more voltages.
    Type: Grant
    Filed: June 27, 2000
    Date of Patent: December 30, 2003
    Assignee: Cypress Semiconductor Corp.
    Inventor: Irfan Rahim
  • Patent number: 6476635
    Abstract: A layout architecture for a programmable logic device comprising one or more adjacent metal lines, a first circuit, and a second circuit. The one or more adjacent metal lines may each comprise a critical path. The first circuit may be configured to present an input signal to each of the one or more adjacent metal lines in response to a configuration signal. The second circuit may be configured to (i) receive a signal from at least one of the one or more adjacent metal lines selected in response to the configuration signal and (ii) generate an output signal in response to the received signal.
    Type: Grant
    Filed: June 28, 2000
    Date of Patent: November 5, 2002
    Assignee: Cypress Semiconductor Corp.
    Inventors: Irfan Rahim, John E. Berg
  • Patent number: 6207991
    Abstract: A method of forming non-volatile memory (e.g., an EEPROM device) and a CMOS device (e.g., a RAM), on a single die or chip, and a structure formed by the method. In one embodiment, the control gate of the storage transistor as well as the isolation gate of the isolation transistor may be formed during the same manufacturing process step, and thus may be formed of the same gate poly material and may have similar thickness.
    Type: Grant
    Filed: March 20, 1998
    Date of Patent: March 27, 2001
    Assignee: Cypress Semiconductor Corp.
    Inventor: Irfan Rahim
  • Patent number: 6124157
    Abstract: A method of forming non-volatile memory (e.g., an EEPROM device) and a CMOS device (e.g., a RAM), on a single die or chip, and a structure formed by the method. In one embodiment, the control gate of the storage transistor as well as the isolation gate of the isolation transistor may be formed during the same manufacturing process step, and thus may be formed of the same gate poly material and may have similar thickness.
    Type: Grant
    Filed: March 20, 1998
    Date of Patent: September 26, 2000
    Assignee: Cypress Semiconductor Corp.
    Inventor: Irfan Rahim
  • Patent number: 6069382
    Abstract: A non-volatile memory cell includes a floating gate having a bottom surface in contact with a tunnel layer formed on the substrate, a top surface, and sidewall surfaces oriented along the bitline direction and along the wordline direction of the memory cell. A dielectric layer covers at least a portion of the top surface and covers at least a portion of the surfaces oriented along the bitline and wordline directions. A control gate overlaps the floating gate over substantially all of its surface area. A plurality of self-aligned sidewall spacers are provided, disposed against at least the dielectric layer and the control gate sidewalls. By overlapping the control gate over the floating gate, a greater surface area is made available for charge storage and/or for increasing the coupling ratio of the memory cell. This allows the width of wing structures to be decreased, while maintaining a high coupling ratio.
    Type: Grant
    Filed: February 11, 1998
    Date of Patent: May 30, 2000
    Assignee: Cypress Semiconductor Corp.
    Inventor: Irfan Rahim
  • Patent number: 5900763
    Abstract: An integrated circuit (10) provides analog and digital circuitry on a common substrate (12). A first digital circuit (14) operates in combination with an analog circuit (18) to perform a useful function. A second duplicate digital circuit (26) is disposed adjacent to the first digital circuit and operates out-of-phase with respect to the first digital circuit. The second duplicate digital circuit introduces voltage spikes equal and opposite to the voltage spikes introduced into the substrate by the first digital circuit. The equal and opposite voltage spikes tend to cancel and thereby minimize cross-talk between the digital and analog circuits. A guard ring (16,28) surrounds each of the first and second digital circuits and the analog circuit to reduce voltage spikes into the substrates. By minimizing cross-talk, the analog circuit operates without interference from the digital circuits.
    Type: Grant
    Filed: October 11, 1994
    Date of Patent: May 4, 1999
    Assignee: Motorola, Inc.
    Inventors: Irfan Rahim, Bor-Yuan Hwang, Kuntal Joardar
  • Patent number: 5405790
    Abstract: A varactor (10, 115, 122) is formed using a BICMOS process flow. An N well (28) of a varactor region (13) is formed in an epitaxial layer (22) by doping the epitaxial layer (22) with an N type dopant. A cathode region (55, 132) is formed in the N well (28) by further doping the N well (28) with the N type dopant. Cathode electrodes (91, 114) are formed by patterning a layer of polysilicon (62, 86) over the epitaxial layer (22). Subsequently, the cathode electrodes (91, 114) are doped with an N type dopant. A region adjacent the cathode region (55, 132) is doped to form a lightly doped region (103, 117). The lightly doped region (103, 117) is doped with a P type dopant to form an anode region (109, 119).
    Type: Grant
    Filed: November 23, 1993
    Date of Patent: April 11, 1995
    Assignee: Motorola, Inc.
    Inventors: Irfan Rahim, Bor-Yuan C. Hwang, Julio Costa