Patents by Inventor Sik K. Lui

Sik K. Lui 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: 20080001646
    Abstract: A semiconductor power device includes a circuit to provide a gate signal wherein the gate signal has a negative temperature coefficient of gate driving voltage for decreasing a gate driving voltage with an increase temperature whereby the semiconductor power device has a net Ids temperature coefficient that is less than or equal to zero. In an exemplary embodiment, the gate voltage driver includes a diode that has a negative forward voltage temperature coefficient connected between a gate and a source of the semiconductor power device. In another embodiment, the gate voltage is integrated with the semiconductor power device manufactured as part of an integrated circuit with the semiconductor power device.
    Type: Application
    Filed: June 30, 2006
    Publication date: January 3, 2008
    Inventors: Sik K. Lui, Anup Bhalla, Sanjay Havanur
  • Publication number: 20070194374
    Abstract: This invention discloses a semiconductor power device that includes a plurality of power transistor cells surrounded by a trench opened in a semiconductor substrate. At least one of the cells constituting an active cell has a source region disposed next to a trenched gate electrically connecting to a gate pad and surrounding the cell. The trenched gate further has a bottom-shielding electrode filled with a gate material disposed below and insulated from the trenched gate. At least one of the cells constituting a source-contacting cell surrounded by the trench with a portion functioning as a source connecting trench is filled with the gate material for electrically connecting between the bottom-shielding electrode and a source metal disposed directly on top of the source connecting trench.
    Type: Application
    Filed: February 17, 2006
    Publication date: August 23, 2007
    Inventors: Anup Bhalla, Sik K. Lui
  • Patent number: 7221195
    Abstract: This invention discloses a new MOSFET device. The MOSFET device has an improved operation characteristic achieved by connecting a shunt FET of low impedance to the MOSFET device. The shunt FET is to shunt a transient current therethrough. The shunt FET is employed for preventing an inadvertent turning on of the MOSFET device. The inadvertent turning on of the MOSFET may occur when a large voltage transient occurs at the drain of the MOSFET device. By connecting the gate of the shunt FET to the drain of the MOSFET device, a low impedance path is provided at the right point of time during the circuit operation to shunt the current without requiring any external circuitry.
    Type: Grant
    Filed: March 18, 2005
    Date of Patent: May 22, 2007
    Assignee: Alpha & Omega Semiconductor, Ltd.
    Inventors: Anup Bhalla, Sik K. Lui
  • Publication number: 20070096093
    Abstract: This invention discloses a method for calibrating a gate resistance measurement of a semiconductor power device that includes a step of forming a RC network on a test area on a semiconductor wafer adjacent to a plurality of semiconductor power chips and measuring a resistance and a capacitance of the RC network to prepare for carrying out a wafer-level measurement calibration of the semiconductor power device. The method further includes a step of connecting a probe card to a set of contact pads on the semiconductor wafer for carrying out the wafer-level measurement calibration followed by performing a gate resistance Rg measurement for the semiconductor power chips.
    Type: Application
    Filed: November 1, 2005
    Publication date: May 3, 2007
    Inventors: Anup Bhalla, Sik-K. Lui, Daniel Ng
  • Patent number: 7208818
    Abstract: A semiconductor package including a relatively thick lead frame having a plurality of leads and a first lead frame pad, the first lead frame pad including a die coupled thereto, bonding wires connecting the die to the plurality of leads, the bonding wires being aluminum, and a resin body encapsulating the die, bonding wires and at least a portion of the lead frame.
    Type: Grant
    Filed: July 20, 2004
    Date of Patent: April 24, 2007
    Assignee: Alpha and Omega Semiconductor Ltd.
    Inventors: Leeshawn Luo, Anup Bhalla, Sik K. Lui, Yueh-Se Ho, Mike F. Chang, Xiao Tian Zhang
  • Patent number: 7183616
    Abstract: This invention discloses a method for configuring a power MOSFET package by packaging several paralleled and separated MOSFET chips in the assembly. The method further includes a step of connecting the gate pad on each of these MOSFET chips with a low-resistance gate bus. The package resistance and inductance are significantly reduced and switching speed and heat dissipation are substantially improved.
    Type: Grant
    Filed: July 30, 2002
    Date of Patent: February 27, 2007
    Assignee: Alpha & Omega Semiconductor, Ltd.
    Inventors: Anup Bhalla, Sik K Lui, Leeshawn Luo, Yueh-Se Ho
  • Patent number: 7122882
    Abstract: A semiconductor integrated circuit package having a common source current sensing circuit includes a main die having an integrated circuit, the main die including a source bonding pad and a gate bonding pad disposed on an upper surface, a leadframe having a leadframe pad disposed under the main die, and a monitoring die including a source bonding pad and a gate bonding pad disposed on an upper surface, the monitoring die being coupled to the main die in such manner that the main die source bonding pad is coupled to the monitoring die source bonding pad and the main die gate bonding pad is coupled to the monitoring die gate bonding pad and such that the main die and monitoring die upper surfaces are adjacent to one another.
    Type: Grant
    Filed: November 2, 2004
    Date of Patent: October 17, 2006
    Assignee: Alpha and Omega Semiconductor Ltd.
    Inventors: Sik K. Lui, Anup Bhalla
  • Patent number: 6841852
    Abstract: A semiconductor integrated circuit package having a leadframe (108) that includes a leadframe pad (103a) disposed under a die (100) and a bonding metal area (101a) that is disposed over at least two adjacent sides of the die. The increase in the bonding metal area (101a) increases the number of interconnections between the metal area (101a) and the die (100) to reduce the electric resistance and inductance. Furthermore, the surface area of the external terminals radiating from the package's plastic body (106) is increased if not maximized so that heat can be dissipated quicker and external terminal resistances reduced. The integrated circuit is applicable for MOSFET devices and the bonding metal area (101a) is used for the source terminal (101). The bonding metal area may have a “L” shape, a “C” shape, a “J” shape, an “I” shape or any combination thereof.
    Type: Grant
    Filed: July 2, 2002
    Date of Patent: January 11, 2005
    Inventors: Leeshawn Luo, Anup Bhalla, Yueh-Se Ho, Sik K. Lui, Mike Chang
  • Publication number: 20040004272
    Abstract: A semiconductor integrated circuit package having a leadframe (108) that includes a leadframe pad (103a) disposed under a die (100) and a bonding metal area (110a) that is disposed over at least two adjacent sides of the die. The increase in the bonding metal area (110a) increases the number of interconnections between the metal area (110a) and the die (100) to reduce the electric resistance and inductance. Furthermore, the surface area of the external terminals radiating from the package's plastic body (106) is increased if not maximized so that heat can be dissipated quicker and external terminal resistances reduced. The integrated circuit is applicable for MOSFET devices and the bonding metal area (101a) is used for the source terminal (101). The bonding metal area may have a “L” shape, a “C” shape, a “J” shape, an “I” shape or any combination thereof.
    Type: Application
    Filed: July 2, 2002
    Publication date: January 8, 2004
    Inventors: Leeshawn Luo, Anup Bhalla, Yueh-Se Ho, Sik K. Lui, Mike Chang
  • Publication number: 20030183924
    Abstract: This invention discloses a method for configuring a power MOSFET package by packaging several paralleled and separated MOSFET chips in the assembly. The method further includes a step of connecting the gate pad on each of these MOSFET chips with a low-resistance gate bus. The package resistance and inductance are significantly reduced and switching speed and heat dissipation are substantially improved.
    Type: Application
    Filed: July 30, 2002
    Publication date: October 2, 2003
    Applicant: Alpha & Omega Semiconductor, LTD.
    Inventors: Anup Bhalla, Sik K. Lui, Leeshawn Luo, Yueh-Se Ho
  • Patent number: 5838624
    Abstract: A circuit improves the reliability of antifuses in certain types of systems by substantially eliminating the continuous undesirable applications of voltages across antifuse terminals. To accomplish this, an antifuse has applied across its two terminals a "reading" or "evaluation" voltage as required by the system operation for a single read or evaluation clock period (typically 5 ns to 30 ns in duration). The signal describing the state of the antifuse is then stored in a latch, register, or other suitable structure for subsequent sampling. In this manner, a low read current flows in the antifuse in response to the standard chip operating voltage for only a short period of time such as a single clock cycle. Thus, continuous voltages across the two terminals of the antifuse are avoided and an unprogrammed antifuse is not inadvertently programmed and a programmed antifuse is not inadvertently converted back to its high impedance state (i.e. "unprogrammed").
    Type: Grant
    Filed: May 2, 1997
    Date of Patent: November 17, 1998
    Assignee: Integrated Device Technology, Inc.
    Inventors: David J. Pilling, Raymond M. Chu, Sik K. Lui
  • Patent number: 5818778
    Abstract: An antifuse redundancy circuit operates with transparency to external circuitry and users. In one embodiment, an antifuse redundancy circuit incorporates two antifuses rather than one. The circuit is arranged so that both antifuses may be simultaneously programmed and read. If a single antifuse is programmed without programming the other antifuse, the antifuse redundancy circuit will register a programmed antifuse. Additionally, if a single programmed antifuse is unintentionally deprogrammed after both antifuses in the redundancy circuit have been programmed, the antifuse redundancy circuit will continue to register a programmed antifuse. The result is both an increase in manufacturing yield and an increase in the reliability of integrated circuits utilizing antifuses.
    Type: Grant
    Filed: March 26, 1997
    Date of Patent: October 6, 1998
    Assignee: Integrated Device Technology, Inc.
    Inventors: Sik K. Lui, Raymond M. Chu, David J. Pilling
  • Patent number: 5680360
    Abstract: A circuit improves the reliability of antifuses in certain types of systems by substantially eliminating the continuous undesirable applications of voltages across antifuse terminals. To accomplish this, an antifuse has applied across its two terminals a "reading" or "evaluation" voltage as required by the system operation for a single read or evaluation clock period (typically 5 ns to 30 ns in duration). The signal describing the state of the antifuse is then stored in a latch, register, or other suitable structure for subsequent sampling. In this manner, a low read current flows in the antifuse in response to the standard chip operating voltage for only a short period of time such as a single clock cycle. Thus, continuous voltages across the two terminals of the antifuse are avoided and an unprogrammed antifuse is not inadvertently programmed and a programmed antifuse is not inadvertently converted back to its high impedance state (i.e. "unprogrammed").
    Type: Grant
    Filed: June 6, 1995
    Date of Patent: October 21, 1997
    Assignee: Integrated Device Technology, Inc.
    Inventors: David J. Pilling, Raymond M. Chu, Sik K. Lui
  • Patent number: 5677888
    Abstract: An antifuse redundancy circuit operates with transparency to external circuitry and users. In one embodiment, an antifuse redundancy circuit incorporates two antifuses rather than one. The circuit is arranged so that both antifuses may be simultaneously programmed and read. If a single antifuse is programmed without programming the other antifuse, the antifuse redundancy circuit will register a programmed antifuse. Additionally, if a single programmed antifuse is unintentionally deprogrammed after both antifuses in the redundancy circuit have been programmed, the antifuse redundancy circuit will continue to register a programmed antifuse. The result is both an increase in manufacturing yield and an increase in the reliability of integrated circuits utilizing antifuses.
    Type: Grant
    Filed: June 6, 1995
    Date of Patent: October 14, 1997
    Assignee: Integrated Device Technology, Inc.
    Inventors: Sik K. Lui, Raymond M. Chu, David J. Pilling
  • Patent number: 5514980
    Abstract: A high resolution sense amplifier and method for sensing the state of antifuses in an integrated circuit is capable of correctly reading even a defectively programmed antifuse having a resistance of up to 20 K.OMEGA. as being programmed. The sense amplifier reads two antifuses at each programmable location, and correctly reads that location as being programmed if either or both of the antifuses at that location have been blown.
    Type: Grant
    Filed: May 31, 1995
    Date of Patent: May 7, 1996
    Assignee: Integrated Device Technology, Inc.
    Inventors: David J. Pilling, Raymond M. Chu, Sik K. Lui
  • Patent number: 5188972
    Abstract: A semiconductor structure having a high precision analog polysilicon capacitor with a self-aligned extrinsic base region of a bipolar transistor is disclosed. The structure is formed by simultaneously forming the dielectric layer of the capacitor with the formation of the base region of the bipolar transistor. A final oxidation step in the formation of the capacitor causes the base region to diffuse to form a self-aligned extrinsic base diffusion region.
    Type: Grant
    Filed: April 28, 1992
    Date of Patent: February 23, 1993
    Assignee: Sierra Semiconductor Corporation
    Inventors: Ying K. Shum, Sik K. Lui