Patents by Inventor Felix C. Li

Felix C. Li 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: 8736042
    Abstract: A semiconductor package configured to attain a thin profile and low moisture sensitivity. Packages of this invention can include a semiconductor die mounted on a die attachment site of a leadframe and further connected with a plurality of elongate I/O leads arranged about the die attach pad and extending in said first direction. The leadframe having an “up-set” bonding pad arranged with a bonding support for supporting a plurality of wire bonds and a large mold flow aperture in the up-set bonding pad. The package encapsulated in a mold material that surrounds the bonding support and flows through the large mold flow aperture to establish well supported wire bonds such that the package has low moisture sensitivity.
    Type: Grant
    Filed: December 13, 2011
    Date of Patent: May 27, 2014
    Assignee: National Semiconductor Corporation
    Inventors: Felix C. Li, Yee Kim Lee, Peng Soon Lim, Terh Kuen Yii, Lee Han Meng@Eugene Lee
  • Publication number: 20120080781
    Abstract: A semiconductor package configured to attain a thin profile and low moisture sensitivity. Packages of this invention can include a semiconductor die mounted on a die attachment site of a leadframe and further connected with a plurality of elongate I/O leads arranged about the die attach pad and extending in said first direction. The leadframe having an “up-set” bonding pad arranged with a bonding support for supporting a plurality of wire bonds and a large mold flow aperture in the up-set bonding pad. The package encapsulated in a mold material that surrounds the bonding support and flows through the large mold flow aperture to establish well supported wire bonds such that the package has low moisture sensitivity.
    Type: Application
    Filed: December 13, 2011
    Publication date: April 5, 2012
    Applicant: NATIONAL SEMICONDUCTOR CORPORATION
    Inventors: Felix C. LI, Yee Kim LEE, Peng Soon LIM, Terh Kuen YII, Lee Han Meng@Eugene LEE
  • Patent number: 8097934
    Abstract: A lead frame and package construction configured to attain a thin profile and low moisture sensitivity. Lead frames of this invention may include a die attach pad having a die attachment site and an elongate ground lead that extends from the die attach pad. The lead frame includes a plurality of elongate I/O leads arranged about the die attach pad and extending away from the die attach pad in at least two directions. An inventive lead frame features “up-set” bonding pads electrically connected with the die attach pad and arranged with a bonding surface for supporting a plurality of wire bonds. The bonding surfaces also constructed to define at least one mold flow aperture for each up-set bonding pad. A package incorporating the lead frame is further disclosed such that the package includes an encapsulant that surrounds the bonding support and flows through the mold flow aperture to establish well supported wire bonds such that the package has low moisture sensitivity.
    Type: Grant
    Filed: August 13, 2008
    Date of Patent: January 17, 2012
    Assignee: National Semiconductor Corporation
    Inventors: Felix C. Li, Yee Kim Lee, Peng Soon Lim, Terh Kuen Yii, Lee Han Meng@Eugene Lee
  • Patent number: 7898088
    Abstract: A semiconductor device, including methods and arrangements for making the same, are described. The device includes an integrated circuit die having a plurality of bond pads. At least one bond pad on the active surface of the die is an extended I/O pad. Each extended I/O pad extends to at least one peripheral side edge of the die.
    Type: Grant
    Filed: October 9, 2007
    Date of Patent: March 1, 2011
    Assignee: National Semiconductor Corporation
    Inventor: Felix C. Li
  • Patent number: 7812463
    Abstract: One aspect of the invention pertains to a semiconductor package suitable for use in high stress environments, such as ones involving high pressures, temperatures and/or corrosive substances. In this aspect, a die and leadframe are fully encapsulated in a first plastic casing. The first plastic casing is fully encapsulated in turn with a second plastic casing. The two casings have different compositions. The first plastic casing, for example, may be made of a thermoset plastic material and the second plastic casing may be made of a thermoplastic material. The first plastic casing may have recesses, indentations and/or slots suitable for securing it to the second plastic casing. In some embodiments, a corrosion resistant coating is added to the second plastic casing. Methods for forming semiconductor packages suitable for use in high stress environments are also described.
    Type: Grant
    Filed: July 10, 2008
    Date of Patent: October 12, 2010
    Assignee: National Semiconductor Corporation
    Inventor: Felix C. Li
  • Publication number: 20100006991
    Abstract: One aspect of the invention pertains to a semiconductor package suitable for use in high stress environments, such as ones involving high pressures, temperatures and/or corrosive substances. In this aspect, a die and leadframe are fully encapsulated in a first plastic casing. The first plastic casing is fully encapsulated in turn with a second plastic casing. The two casings have different compositions. The first plastic casing, for example, may be made of a thermoset plastic material and the second plastic casing may be made of a thermoplastic material. The first plastic casing may have recesses, indentations and/or slots suitable for securing it to the second plastic casing. In some embodiments, a corrosion resistant coating is added to the second plastic casing. Methods for forming semiconductor packages suitable for use in high stress environments are also described.
    Type: Application
    Filed: July 10, 2008
    Publication date: January 14, 2010
    Applicant: NATIONAL SEMICONDUCTOR CORPORATION
    Inventor: Felix C. LI
  • Patent number: 7564130
    Abstract: A semiconductor device is provided, which comprises: a die including an active surface; a multiplicity of bond pads formed on the active surface of the die, wherein a first one of the bond pads is larger than a second one of the bond pads; and a multiplicity of solder bumps, each formed over a corresponding bond pad, wherein the multiplicity of solder bumps include a first solder bump formed over the first bond pad and a second solder bump formed over the second bond pad, the first solder bump having a footprint that is substantially larger than the second solder bump and a maximum diameter that is substantially larger than the second solder bump.
    Type: Grant
    Filed: July 6, 2007
    Date of Patent: July 21, 2009
    Assignee: National Semiconductor Corporation
    Inventor: Felix C. Li
  • Publication number: 20090091016
    Abstract: A semiconductor device, including methods and arrangements for making the same, are described. The device includes an integrated circuit die having a plurality of bond pads. At least one bond pad on the active surface of the die is an extended I/O pad. Each extended I/O pad extends to at least one peripheral side edge of the die.
    Type: Application
    Filed: October 9, 2007
    Publication date: April 9, 2009
    Applicant: NATIONAL SEMICONDUCTOR CORPORATION
    Inventor: Felix C. Li
  • Patent number: 7479411
    Abstract: An apparatus and method for forming a substantially continuous solder bump around the periphery of each dice on a flip chip wafer is disclosed. The solder bump is provided on each die so that when it is singulated from the wafer and mounted onto a substrate, the solder bump around the periphery acts to hermetically attach and seal the die to the substrate. According to various embodiments of the invention, the continuous solder bump may be coupled to either a ground plane or a power supply on the substrate. The method includes fabricating a plurality of integrated circuit dice on a first surface of a semiconductor wafer. After the integrated circuitry is fabricated, a substantially continuous solder bump is formed on the periphery of each of the dice on the wafer.
    Type: Grant
    Filed: August 26, 2005
    Date of Patent: January 20, 2009
    Assignee: National Semiconductor Corporation
    Inventor: Felix C. Li
  • Patent number: 7456503
    Abstract: A semiconductor device, including methods and arrangements for making the same, are described. The device includes an integrated circuit die having a plurality of bond pads. At least one bond pad on the active surface of the die is an extended I/O pad. Each extended I/O pad extends to at least one peripheral side edge of the die. Solder fillets are formed between the extended I/O pads and corresponding contacts on a substrate.
    Type: Grant
    Filed: October 9, 2007
    Date of Patent: November 25, 2008
    Assignee: National Semiconductor Corporation
    Inventor: Felix C. Li
  • Patent number: 7432583
    Abstract: A semiconductor package is provided with an internal package formed in the cavity of the external leadless leadframe package (LLP). The internal package is a leadless leadframe package and provides a substrate for mounting one or more die and passive devices to form the external LLP. By arranging the die and passive components on the internal package, higher chip density and a smaller form factor may be achieved.
    Type: Grant
    Filed: July 8, 2004
    Date of Patent: October 7, 2008
    Assignee: National Semiconductor Corporation
    Inventors: Felix C. Li, Jaime A. Bayan
  • Patent number: 7425503
    Abstract: An apparatus and method for an enhanced thermally conductive package for high powered semiconductor devices. The package includes a semiconductor die having an active surface and a non-active surface and a metal layer formed on the non-active surface of the die. The package is intended to be mounted onto a metal pad provided on a printed circuit board. A solder is used to affix the metal layer on the non-active surface of the die to the metal pad of the printed circuit board. The interface between the die and the printed circuit board thus includes just three metal layers, including the non-active surface of the die, the solder, and the metal pad on the printed circuit board. The reduced number of metal layers improves heat dissipation and thermal conductivity of the package.
    Type: Grant
    Filed: July 14, 2006
    Date of Patent: September 16, 2008
    Assignee: National Semiconductor Corporation
    Inventor: Felix C. Li
  • Publication number: 20080061408
    Abstract: A novel, small outline molded, high voltage, lead frame based integrated circuit package is described. The integrated circuit die has at least one high voltage I/O pad that is electrically connected to an associated high voltage lead/pin in the lead frame. All of the pins of the lead frame that are not high voltage pins have a standard pitch between adjacent pins on the same side of the lead frame that is no more than approximately 0.5 mm. The pitch between each high voltage pin and an adjacent pin is double the standard pitch. The high voltage I/O pad is arranged to handle output signals having voltages of at least 30 volts. In some embodiments, the lead frame is formed from a copper or copper alloy based material and exposed portions of the pins are plated with a lead/tin based solder material.
    Type: Application
    Filed: October 25, 2006
    Publication date: March 13, 2008
    Applicant: NATIONAL SEMICONDUCTOR CORPORATION
    Inventors: Felix C. Li, Carlos Sanchez, Walter Bacharowski, Willem Johannes Kindt
  • Patent number: 7109587
    Abstract: An apparatus and method for an enhanced thermally conductive package for high powered semiconductor devices. The package includes a semiconductor die having an active surface and a non-active surface and a metal layer formed on the non-active surface of the die. The package is intended to be mounted onto a metal pad provided on a printed circuit board. A solder is used to affix the metal layer on the non-active surface of the die to the metal pad of the printed circuit board. The interface between the die and the printed circuit board thus includes just three metal layers, including the non-active surface of the die, the solder, and the metal pad on the printed circuit board. The reduced number of metal layers improves heat dissipation and thermal conductivity of the package.
    Type: Grant
    Filed: May 25, 2004
    Date of Patent: September 19, 2006
    Assignee: National Semiconductor Corporation
    Inventor: Felix C. Li
  • Patent number: 7023074
    Abstract: Methods of fabricating leadless packages are described that provide good solder joint reliability. In most respects, the packages are fabricated in a manner similar to current lead frame based leadless packaging techniques. However, at some point in the process, the contacts are provided with undercut regions that are left exposed during solder plating so that the solder plating also covers the exposed side and undercut segments of the contacts. When the resultant devices are soldered to an appropriate substrate (after singulation), each resulting solder joint includes a fillet that adheres very well to the undercut portion of contact. This provides a high quality solder joint that can be visually inspected from the side of the package.
    Type: Grant
    Filed: January 3, 2005
    Date of Patent: April 4, 2006
    Assignee: National Semiconductor Corporation
    Inventors: Felix C. Li, Jaime A. Bayan, Santhiran Nadarajah, Ah Lek Hu
  • Patent number: 7005728
    Abstract: A substrate for use in an inline IC package is designed such that its die attach pad and leads each have a number of protrusions and recesses. These protrusions and recesses create an irregular surface that provides better adhesion to encapsulant material than conventional leads and die attach pads, whose smooth, straight surfaces risk delamination of the encapsulant material.
    Type: Grant
    Filed: June 3, 2004
    Date of Patent: February 28, 2006
    Assignee: National Semiconductor Corporation
    Inventor: Felix C. Li
  • Patent number: 6956291
    Abstract: An apparatus and method for forming a substantially continuous solder bump around the periphery of each dice on a flip chip wafer is disclosed. The solder bump is provided on each die so that when it is singulated from the wafer and mounted onto a substrate, the solder bump around the periphery acts to hermetically attach and seal the die to the substrate. According to various embodiments of the invention, the continuous solder bump may be coupled to either a ground plane or a power supply on the substrate. The method includes fabricating a plurality of integrated circuit dice on a first surface of a semiconductor wafer. After the integrated circuitry is fabricated, a substantially continuous solder bump is formed on the periphery of each of the dice on the wafer.
    Type: Grant
    Filed: January 16, 2003
    Date of Patent: October 18, 2005
    Assignee: National Semiconductor Corporation
    Inventor: Felix C. Li
  • Patent number: 6872599
    Abstract: Methods of fabricating leadless packages are described that provide good solder joint reliability. In most respects, the packages are fabricated in a manner similar to current lead frame based leadless packaging techniques. However, at some point in the process, the contacts are provided with undercut regions that are left exposed during solder plating so that the solder plating also covers the exposed side and undercut segments of the contacts. When the resultant devices are soldered to an appropriate substrate (after singulation), each resulting solder joint includes a fillet that adheres very well to the undercut portion of contact. This provides a high quality solder joint that can be visually inspected from the side of the package.
    Type: Grant
    Filed: December 10, 2002
    Date of Patent: March 29, 2005
    Assignee: National Semiconductor Corporation
    Inventors: Felix C. Li, Jaime A. Bayan, Santhiran Nadarajah, Ah Lek Hu
  • Patent number: 6781243
    Abstract: A semiconductor package is provided with an internal package formed in the cavity of the external leadless leadframe package (LLP). The internal package is a leadless leadframe package and provides a substrate for mounting one or more die and passive devices to form the external LLP. By arranging the die and passive components on the internal package, higher chip density and a smaller form factor may be achieved.
    Type: Grant
    Filed: January 22, 2003
    Date of Patent: August 24, 2004
    Assignee: National Semiconductor Corporation
    Inventors: Felix C. Li, Jaime A. Bayan