Patents by Inventor Mujahid Muhammad

Mujahid Muhammad 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).

  • Publication number: 20120091530
    Abstract: An electrostatic discharge (ESD) protection device for an integrated circuit includes a buried layer of a first polarity type formed in a substrate of a second polarity type. A well region of the second polarity type is formed above the buried layer. An FET of the first polarity type is formed within the well region. An inner pair of shallow wells of the first polarity type is disposed adjacent to source and drain diffusion regions of the FET, the inner pair of shallow wells having a depth such that a bottom of the inner pair of shallow wells is above a top of the buried layer. An outer pair of deep wells of the first polarity type extends down to the top of the buried layer such that the outer pair of deep wells and the buried layer define a perimeter of the well region of the second polarity type.
    Type: Application
    Filed: October 19, 2010
    Publication date: April 19, 2012
    Applicant: INTERNATIONAL BUSINESS MACHINES CORPORATION
    Inventors: John B. Campi, JR., Shunhua T. Chang, Kiran V. Chatty, Robert J. Gauthier, JR., Junjun Li, Rahul Mishra, Mujahid Muhammad
  • Publication number: 20120043583
    Abstract: A low leakage, low capacitance diode based triggered electrostatic discharge (ESD) silicon controlled rectifiers (SCR), methods of manufacture and design structure are provided. The method includes providing a silicon film on an insulator layer. The method further includes forming isolation regions which extend from an upper side of the silicon layer to the insulator layer. The method further includes forming one or more diodes in the silicon layer, including a p+ region and an n+ region formed in a well bordered by the isolation regions. The isolation regions isolate the one or more diodes in a vertical direction and the insulator layer isolates the one or more diodes from an underlying P or N type substrate, in a horizontal direction.
    Type: Application
    Filed: August 20, 2010
    Publication date: February 23, 2012
    Applicant: INTERNATIONAL BUSINESS MACHINES CORPORATION
    Inventors: Michel J. ABOU-KHALIL, Shunhua T. CHANG, Kiran V. CHATTY, Robert J. GAUTHIER, JR., Junjun LI, Mujahid MUHAMMAD
  • Publication number: 20110286135
    Abstract: An enhanced turn-on time SCR based electrostatic discharge (ESD) protection circuit includes an integrated JFET, method of use and design structure. The enhanced turn-on time silicon controlled rectifier (SCR) based electrostatic discharge (ESD) protection circuit includes an integrated JFET in series with an NPN base.
    Type: Application
    Filed: May 18, 2010
    Publication date: November 24, 2011
    Applicant: INTERNATIONAL BUSINESS MACHINES CORPORATION
    Inventors: John B. CAMPI, JR., Shunhua T. CHANG, Kiran V. CHATTY, Robert J. GAUTHIER, JR., Mujahid MUHAMMAD
  • Publication number: 20100265622
    Abstract: A robust ESD protection circuit, method and design structure for tolerant and failsafe designs are disclosed. A circuit includes a middle junction control circuit that turns off a top NFET of a stacked NFET electrostatic discharge (ESD) protection circuit during an ESD event.
    Type: Application
    Filed: April 15, 2009
    Publication date: October 21, 2010
    Applicant: INTERNATIONAL BUSINESS MACHINES CORPORATION
    Inventors: John B. CAMPI, JR., Shunhua T. CHANG, Kiran V. CHATTY, Robert J. GAUTHIER, JR., Junjun LI, Mujahid MUHAMMAD
  • Publication number: 20100246076
    Abstract: A semiconductor circuit for electric overstress (EOS) protection is provided. The semiconductor circuit employs an electrostatic discharge (ESD) protection circuit, which has a resistor-capacitor (RC) time-delay network connected to a discharge capacitor. An electronic component that has voltage snapback property or a diodic behavior is connected to alter the logic state of the gate of the discharge transistor under an EOS event. Particularly, the electronic component is configured to turn on the gate of the discharge capacitor throughout the duration of an electrical overstress (EOS) condition as well as throughout the duration of an ESD event. A design structure may be employed to design or manufacture a semiconductor circuit that provides protection against an EOS condition without time limitation, i.e., without being limited by the time constant of the RC time delay network for EOS events that last longer than 1 microsecond.
    Type: Application
    Filed: December 7, 2009
    Publication date: September 30, 2010
    Applicant: International Business Machines Corporation
    Inventors: John B. Campi, JR., Shunhua T. Chang, Kiran V. Chatty, Robert J. Gauthier, JR., Junjun Li, Mujahid Muhammad
  • Publication number: 20100181621
    Abstract: An integrated circuit, design structures and methods of forming the integrated circuit which includes a signal pad ESD coupled to an I/O signal pad and a power supply ESD coupled to a source VDD. The signal pad ESD and the power supply ESD are integrated in a single ESD structure.
    Type: Application
    Filed: January 19, 2009
    Publication date: July 22, 2010
    Applicant: International Business Machines Corporation
    Inventors: Shunhua T. Chang, Kiran V. Chatty, Robert J. Gauthier, JR., Mujahid Muhammad
  • Publication number: 20090231766
    Abstract: A structure and method of fabricating electrostatic discharge (EDS) circuitry in an integrated circuit chip by integrating a lateral bipolar, either a p-n-p with a NMOSFET or a n-p-n with a PMOSFET within a triple well. The lateral bipolar preferably includes diodes at the I/O and/or the VDDs of the circuitry.
    Type: Application
    Filed: March 14, 2008
    Publication date: September 17, 2009
    Inventors: Shunhua Chang, Kiran V. Chatty, Robert J. Gauthier, JR., Mujahid Muhammad
  • Publication number: 20090026492
    Abstract: The components of a silicon controlled rectifier, which are a p-doped anode, an n-well middle region, a p-well middle region, and an n-doped cathode, are formed along sidewalls and a bottom surface of a shallow trench isolation structure. The p-doped anode and the n-doped cathode are formed directly underneath a top surface of a silicon substrate. A trigger mechanism that provides an instantaneous turn-on current to latch the silicon controlled rectifier to an on-state is also provided. The trigger mechanism provides a temporary surge in the voltage of the p-doped middle region, causing the instantaneous turn-on current to flow from the p-doped middle region to the n-doped cathode. Combined with the proximity of the p-doped anode to the n-doped cathode, the trigger mechanism provides a fast turn on and a short low resistance current path for the electrostatic discharge protection circuit.
    Type: Application
    Filed: July 25, 2007
    Publication date: January 29, 2009
    Inventors: Kiran V. Chatty, Robert J. Gauthier, JR., Dimitrios K. Kontos, Mujahid Muhammad
  • Patent number: 7457086
    Abstract: Method and device for protecting against electrostatic discharge. The method includes configuring a gate of at least one upper transistor of a transistor network connected between power rails to be biased to a prescribed value, and coupling an electrostatic discharge event to a gate of a lower transistor of the transistor network. The at least one upper and at least one lower transistors of the transistor network are respectively coupled between the power rails from a higher voltage to a lower voltage.
    Type: Grant
    Filed: December 21, 2006
    Date of Patent: November 25, 2008
    Assignee: International Business Machines Corporation
    Inventors: Kiran V. Chatty, Robert J. Gauthier, Jr., Mahmoud A. Mousa, Mujahid Muhammad, Christopher S. Putnam
  • Publication number: 20070097570
    Abstract: Method and device for protecting against electrostatic discharge. The method includes configuring a gate of at least one upper transistor of a transistor network connected between power rails to be biased to a prescribed value, and coupling an electrostatic discharge event to a gate of a lower transistor of the transistor network. The at least one upper and at least one lower transistors of the transistor network are respectively coupled between the power rails from a higher voltage to a lower voltage.
    Type: Application
    Filed: December 21, 2006
    Publication date: May 3, 2007
    Applicant: INTERNATIONAL BUSINESS MACHINES CORPORATION
    Inventors: Kiran CHATTY, Robert GAUTHIER, Mahmoud MOUSA, Mujahid MUHAMMAD, Christopher PUTNAM
  • Patent number: 7203045
    Abstract: A structure and apparatus is provided for an electrostatic discharge power clamp, for use with high voltage power supplies. The power clamp includes a network of transistor devices, for example, nFETs arranged in series between a power rail and a ground rail. The first transistor device is biased into a partially on-state, and thus, neither device sees the full voltage potential between the power rail and the ground rail. Accordingly, the power clamp can function in voltage environments higher than the native voltage of the transistor devices. Additionally, the second transistor device is controlled by an RC network functioning as a trigger which allows the second transistor device to turn on during a voltage spike such as occurs during an ESD event. The capacitor of the RC network may be small thereby requiring small real estate on the integrated circuit. The clamp may have fast turn-on times as well as conducting current for long periods of time after turning on.
    Type: Grant
    Filed: October 1, 2004
    Date of Patent: April 10, 2007
    Assignee: International Business Machines Corporation
    Inventors: Kiran V. Chatty, Robert J. Gauthier, Jr., Mahmoud A. Mousa, Mujahid Muhammad, Christopher S. Putnam
  • Patent number: 7138313
    Abstract: A method of forming a self-aligned SOI diode, the method comprising depositing a protective structure over a substrate; implanting a plurality of diffusion regions of variable dopant types in an area between at least one pair of isolation regions in the substrate, the plurality of diffusion regions separated by a diode junction, wherein the implanting aligns an upper surface of the diode junction with the protective structure; and removing the protective structure. The method further comprises forming a silicide layer over the diffusion regions and aligned with the protective structure. The protective structure comprises a hard mask, wherein the hard mask comprises a silicon nitride layer. Alternatively, the protective structure comprises a polysilicon gate and insulating spacers on opposite sides of the gate. Furthermore, in the removing step, the spacers remain on the substrate.
    Type: Grant
    Filed: March 31, 2004
    Date of Patent: November 21, 2006
    Assignee: International Business Machines Corporation
    Inventors: Kiran V. Chatty, Robert J. Gauthier, Jr., Mujahid Muhammad, Christopher S. Putnam
  • Patent number: 7098513
    Abstract: A field effect transistor with associated parasitic lateral npn bipolar junction transistor includes a source region in a substrate, a channel region in the substrate laterally adjacent to the source region, a drain region in the substrate laterally adjacent to the channel region, and a gate above the channel region of the substrate. In addition, a reduced trigger voltage region of the substrate is positioned below the drain region. The reduced trigger voltage region has a threshold voltage of about zero and comprises an undoped region of the pure wafer substrate. Thus, the reduced trigger voltage region is free of implanted N-type and P-type doping.
    Type: Grant
    Filed: January 17, 2005
    Date of Patent: August 29, 2006
    Assignee: International Business Machines Corporation
    Inventors: Kiran V. Chatty, Robert J. Gauthier, Terence B. Hook, Christopher S. Putnam, Mujahid Muhammad
  • Publication number: 20060157799
    Abstract: A field effect transistor with associated parasitic lateral npn bipolar junction transistor includes a source region in a substrate, a channel region in the substrate laterally adjacent to the source region, a drain region in the substrate laterally adjacent to the channel region, and a gate above the channel region of the substrate. In addition, a reduced trigger voltage region of the substrate is positioned below the drain region. The reduced trigger voltage region has a threshold voltage of about zero and comprises an undoped region of the pure wafer substrate. Thus, the reduced trigger voltage region is free of implanted N-type and P-type doping.
    Type: Application
    Filed: January 17, 2005
    Publication date: July 20, 2006
    Applicant: INTERNATIONAL BUSINESS MACHINES CORPORATION
    Inventors: Kiran Chatty, Robert Gauthier, Terence Hook, Christopher Putnam, Mujahid Muhammad
  • Publication number: 20060072267
    Abstract: A structure and apparatus is provided for an electrostatic discharge power clamp, for use with high voltage power supplies. The power clamp includes a network of transistor devices, for example, nFETs arranged in series between a power rail and a ground rail. The first transistor device is biased into a partially on-state, and thus, neither device sees the full voltage potential between the power rail and the ground rail. Accordingly, the power clamp can function in voltage environments higher than the native voltage of the transistor devices. Additionally, the second transistor device is controlled by an RC network functioning as a trigger which allows the second transistor device to turn on during a voltage spike such as occurs during an ESD event. The capacitor of the RC network may be small thereby requiring small real estate on the integrated circuit. The clamp may have fast turn-on times as well as conducting current for long periods of time after turning on.
    Type: Application
    Filed: October 1, 2004
    Publication date: April 6, 2006
    Applicant: INTERNATIONAL BUSINESS MACHINES CORPORATION
    Inventors: Kiran Chatty, Robert Gauthier, Mahmoud Mousa, Mujahid Muhammad, Christopher Putnam
  • Patent number: 7005686
    Abstract: Disclosed is a method for increasing substrate resistance in a silicon controlled rectifier in order to decrease turn on time so that the silicon controlled rectifier may be used as an effective electrostatic discharge protection device to protect against HBM, MM and CDM discharge events. Additionally, disclosed is an improved SCR structure that is adapted for use as an electrostatic discharge device to protect against human body model events by delivering an electrostatic discharge current directly to a ground rail. The improved SCR structure incorporates various features for increasing substrate resistance and, thereby, for decreasing turn on time. These features include a second n-well that functions as an obstacle to current flow, a narrow current flow channel between co-planar buried n-bands connected to a lower portion of the second n-well, a zero threshold voltage area, and an external resistor electrically connected between the SCR and the ground rail.
    Type: Grant
    Filed: July 26, 2005
    Date of Patent: February 28, 2006
    Assignee: International Business Machines Corporation
    Inventors: Kiran V. Chatty, Robert J. Gauthier, Jr., Mujahid Muhammad, Andreas D. Stricker, Min Woo
  • Publication number: 20050227418
    Abstract: A method of forming a self-aligned SOI diode, the method comprising depositing a protective structure over a substrate; implanting a plurality of diffusion regions of variable dopant types in an area between at least one pair of isolation regions in the substrate, the plurality of diffusion regions separated by a diode junction, wherein the implanting aligns an upper surface of the diode junction with the protective structure; and removing the protective structure. The method further comprises forming a silicide layer over the diffusion regions and aligned with the protective structure. The protective structure comprises a hard mask, wherein the hard mask comprises a silicon nitride layer. Alternatively, the protective structure comprises a polysilicon gate and insulating spacers on opposite sides of the gate. Furthermore, in the removing step, the spacers remain on the substrate.
    Type: Application
    Filed: March 31, 2004
    Publication date: October 13, 2005
    Applicant: INTERNATIONAL BUSINESS MACHINES CORPORATION
    Inventors: Kiran Chatty, Robert Gauthier, Mujahid Muhammad, Christopher Putnam
  • Publication number: 20050224882
    Abstract: An ESD NMOSFET, and a method for lowering a ESD NMOSFET trigger voltage. An ESD NMOSFET is configured in triple well CMOS architecture where the first well is separated from second and third wells by respective shallow well isolation regions. The first well is also separated from the substrate along the bottom by a conductive band region. A substrate contact is located outside of the first, second and third wells, and provides a current path during an ESD event from the first well. Source and drain regions are formed in the first well, to form an FET with the drain being connected to an I/O pad which is subject to an ESD event. A resistive path extends through an opening in the conductive band region to a substrate contact, providing an increased I/O pad to substrate resistance which decreases the trigger voltage for the ESD NMOSFET.
    Type: Application
    Filed: April 8, 2004
    Publication date: October 13, 2005
    Applicant: INTERNATIONAL BUSINESS MACHINES CORPORATION
    Inventors: Kiran Chatty, Robert Gauthier, Mujahid Muhammad, Christopher Putnam
  • Publication number: 20050085028
    Abstract: A method and structure for protection against latch-up is provided. Integrated circuits manufactured in accordance with the present disclosure feature well and substrate contacts of varying periodicity. Such a strategy enables maximizing the design of an integrated circuit as to the suppression of latch-up while concurrently optimizing available area on the chip allocable to circuit design. This method and structure is particularly beneficial to protect against cable discharge events and other discharge occurrences prone to injecting large current densities into an integrated circuit.
    Type: Application
    Filed: October 21, 2003
    Publication date: April 21, 2005
    Applicant: International Business Machines Corporation
    Inventors: Kiran Chatty, Peter Cottrell, Robert Gauthier, Mujahid Muhammad
  • Publication number: 20050045952
    Abstract: A method and apparatus for protection against electrostatic discharge (ESD) with improved latch-up robustness featuring a silicide blocked p-type field effect transistor is disclosed. The transistor has a snapback voltage that is less than the breakdown voltage of its gate oxide. The transistor is part of an integrated circuit and coupled to an I/O pad having no n-diffusions connected directly to it. A given integrated circuit may employ one or more the transistors configured in accordance with the invention that are associated with one or more I/O pads within the integrated circuit.
    Type: Application
    Filed: August 27, 2003
    Publication date: March 3, 2005
    Applicant: INTERNATIONAL BUSINESS MACHINES CORPORATION
    Inventors: Kiran Chatty, Robert Gauthier, Mujahid Muhammad, Christopher Putnam