Patents by Inventor Kin Pui Kwan

Kin Pui Kwan 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: 9806006
    Abstract: Various structures and fabrication methods for leadless plastic chip carrier (QFN) packages which utilize carriers in strip format, wherein the leads (or terminals) are formed to be electrically isolated from one another within each unit and in which the units are formed to be electrically isolated from one another within the strip using chemical etching techniques.
    Type: Grant
    Filed: September 20, 2007
    Date of Patent: October 31, 2017
    Assignee: UTAC HEADQUARTERS PTD. LTD.
    Inventors: Tung Lok Li, Kin Pui Kwan
  • Patent number: 9520306
    Abstract: A process for fabricating an integrated circuit package includes selectively etching a leadframe strip to define a die attach pad and a plurality of contact pads. At least one side of the die attach pad has a plurality of spaced apart pad portions. A semiconductor die is mounted to the die attach pad and wires are bonded from the semiconductor die to respective ones of the contact pads. A first surface of the leadframe strip, including the semiconductor die and wire bonds, is encapsulated in a molding material such that at least one surface of the leadframe strip is exposed. The integrated circuit package is singulated from a remainder of the leadframe strip.
    Type: Grant
    Filed: September 14, 2012
    Date of Patent: December 13, 2016
    Assignee: UTAC HEADQUARTERS PTE. LTD.
    Inventors: Geraldine Tsui Yee Lin, Walter de Munnik, Kin Pui Kwan, Wing Him Lau, Kwok Cheung Tsang, Chun Ho Fan, Neil McLellan
  • Publication number: 20160013075
    Abstract: A process for fabricating an integrated circuit package includes selectively etching a leadframe strip to define a die attach pad and a plurality of contact pads. At least one side of the die attach pad has a plurality of spaced apart pad portions. A semiconductor die is mounted to the die attach pad and wires are bonded from the semiconductor die to respective ones of the contact pads. A first surface of the leadframe strip, including the semiconductor die and wire bonds, is encapsulated in a molding material such that at least one surface of the leadframe strip is exposed. The integrated circuit package is singulated from a remainder of the leadframe strip.
    Type: Application
    Filed: September 14, 2012
    Publication date: January 14, 2016
    Inventors: Geraldine Tsui Yee LIN, Walter de MUNNIK, Kin Pui KWAN, Wing Him LAU, Kwok Cheung TSANG, Chun Ho FAN, Neil McLELLAN
  • Patent number: 8330270
    Abstract: An integrated circuit package having a selectively etched leadframe strip defining a die attach pad and a plurality of contact pads, at least one side of the die attach pad having a plurality of spaced apart pad portions; a semiconductor die mounted to the die attach pad and wires bonding the semiconductor die to respective ones of the contact pads; a first surface of the leadframe strip, including the semiconductor die and wire bonds, encapsulated in a molding material such that at least one surface of the leadframe strip is exposed, and wherein solder paste is disposed on said contact pads and said at least one side of said die attach pad.
    Type: Grant
    Filed: December 9, 2004
    Date of Patent: December 11, 2012
    Assignee: UTAC Hong Kong Limited
    Inventors: Geraldine Tsui Yee Lin, Walter de Munnik, Kin Pui Kwan, Wing Him Lau, Kwok Cheung Tsang, Chun Ho Fan, Neil McLellan
  • Publication number: 20110284495
    Abstract: Various structures and fabrication methods for leadless plastic chip carrier (QFN) packages which utilize carriers in strip format, wherein the leads (or terminals) are formed to be electrically isolated from one another within each unit and in which the units are formed to be electrically isolated from one another within the strip using chemical etching techniques.
    Type: Application
    Filed: September 20, 2007
    Publication date: November 24, 2011
    Applicant: ASAT LIMITED
    Inventors: Tung Lok Li, Kwok Cheung Tsang, Kin Pui Kwan
  • Patent number: 7449771
    Abstract: A method of fabricating an integrated circuit package. The method includes providing a first leadframe and a second leadframe, laminating the second leadframe to a portion of the first leadframe in order to create a multi-layer laminated leadframe, and mounting a semiconductor die on another portion of the first leadframe.
    Type: Grant
    Filed: October 9, 2003
    Date of Patent: November 11, 2008
    Assignee: ASAT Ltd.
    Inventors: Chun Ho Fan, Tsui Yee Lin, Kin Pui Kwan, Shui Ming Tse, Wing Him Lau, Shuk Man Wong
  • Patent number: 7358119
    Abstract: A process for fabricating an integrated circuit package. Metal is plated up on a substrate to provide a plurality of contact pads and a plurality of fiducial markings on a periphery of the contacts. A transparent mask is selectively deposited on the substrate, over the fiducial markings. A semiconductor die is mounted on the substrate such that the contact pads circumscribe the semiconductor die and the semiconductor die is wire bonded to ones of the contact pads. The wire bonds are encapsulated and the semiconductor die and contact pads are covered in a molding material. The substrate is selectively etched to thereby etch away the substrate underneath the contact pads and the semiconductor die. The integrated circuit package is singulated from other integrated circuit packages by sawing using the fiducial markings.
    Type: Grant
    Filed: January 12, 2005
    Date of Patent: April 15, 2008
    Assignee: Asat Ltd.
    Inventors: Neil McLellan, Serafin Pedron, Leo M. Higgins, III, Kwok Cheung Tsang, Kin Pui Kwan
  • Patent number: 7271032
    Abstract: A leadless plastic chip carrier is constructed by half etching one or both sides of the package design onto a leadframe strip so as to create unique design features such as power and/or ground ring surrounding the die attach pad, interlocking rivet head construction for the contact pads, and an interlocking pattern for the die attach pad. After wire bonding and molding, a further etching is performed to isolate and expose contact pads. Singulation of individual chip packages from the leadframe strip is then performed by saw singulation or die punching.
    Type: Grant
    Filed: May 6, 2005
    Date of Patent: September 18, 2007
    Assignee: ASAT Ltd.
    Inventors: Neil McLellan, Chun Ho Fan, Kwok Cheung Tsang, Kin Pui Kwan, Wing Him Lau
  • Patent number: 7270867
    Abstract: A process for fabricating a leadless plastic chip carrier includes selectively depositing a plurality of base layers on a first surface of a base of a leadframe strip to at least partially define a die attach pad and at least one row of contact pads. At least one further layer is selectively deposited on portions of the plurality of layers to further define at least the contact pads. The leadframe strip is then treated with a surface preparation. A semiconductor die is mounted to the die attach pad, followed by wire bonding the semiconductor die to at least the contact pads. Molding the semiconductor die, the wire bonds, the die attach pad and the contact pads on the surface of the leadframe strip, in a molding compound follows. The leadframe strip is etched to expose the contact pads and the die attach pad and the leadless plastic chip carrier is singulated from a remainder of the leadframe strip.
    Type: Grant
    Filed: December 22, 2004
    Date of Patent: September 18, 2007
    Assignee: ASAT Ltd.
    Inventors: Kin Pui Kwan, Wing Him Lau, Kwok Cheung Tsang, Chun Ho Fan, Neil McLellan
  • Patent number: 7232755
    Abstract: A process for fabricating a pad frame for an integrated circuit package includes building up metal on selective portions of a first side of a substrate to define a plurality of contact pads disposed in a first layer of dielectric material, depositing a metal seed layer on an exposed side of the contact pads and the dielectric material, applying a second metal layer on the metal seed layer, selectively etching the second metal layer and the metal seed layer to provide pad frame circuitry, and building up metal on selective portions of the pad frame circuitry to define a plurality of die connect pads separated by a second layer of dielectric material, the die connect pads being electrically connected to the contact pads by the pad frame circuitry.
    Type: Grant
    Filed: August 2, 2005
    Date of Patent: June 19, 2007
    Assignee: ASAT Ltd.
    Inventors: Neil McLellan, Chun Ho Fan, Kwok Cheung Tsang, Kin Pui Kwan
  • Patent number: 7226811
    Abstract: A process for fabricating a leadless plastic chip carrier includes laminating a first metal strip to a second metal strip to form a leadframe strip, selectively etching the first metal strip to define at least a row of contact pads, mounting a semiconductor die to either a die attach pad or the second metal strip and wire bonding the semiconductor die to ones of the contact pads, encapsulating a top surface of the leadframe strip in a molding material, removing the second metal strip, thereby exposing the die attach pad and the at least one row of contact pads, and singulating the leadless plastic chip carrier from the leadframe strip.
    Type: Grant
    Filed: July 6, 2005
    Date of Patent: June 5, 2007
    Assignee: ASAT Ltd.
    Inventors: Neil McLellan, Chun Ho Fan, Kin Pui Kwan, Wing Him Lau
  • Patent number: 7081403
    Abstract: A leadless plastic chip carrier is fabricated by selectively etching a leadframe strip to reduce a thickness of the strip at a portion thereof. Selectively masking the surface of the leadframe strip using a mask, follows selectively etching, to provide exposed areas of the surface at the portion and contact pad areas on leadframe the strip. At least one layer of metal is deposited on the exposed areas to define a die attach pad on the portion of the leadframe strip with reduced thickness and to define contact pads on the surface of the strip. At least one semiconductor die is mounted to the die attach pad, followed by wire bonding the at least one semiconductor die to ones of the contact pads. The at least one semiconductor die, the wire bonds, and the contact pads are covered with an overmold material and the leadframe strip is etched to thereby remove the leadframe strip. The leadless plastic chip carrier is singulated from the leadframe strip.
    Type: Grant
    Filed: June 13, 2005
    Date of Patent: July 25, 2006
    Assignee: ASAT Ltd.
    Inventors: Mohan Kirloskar, Chun Ho Fan, Kwok Cheung Tsang, Kin Pui Kwan
  • Patent number: 7009286
    Abstract: A leadless plastic chip carrier is fabricated by selectively etching a leadframe strip to reduce a thickness of the strip at a portion thereof. Selectively masking the surface of the leadframe strip using a mask, follows selectively etching, to provide exposed areas of the surface at the portion and contact pad areas on leadframe the strip. At least one layer of metal is deposited on the exposed areas to define a die attach pad on the portion of the leadframe strip with reduced thickness and to define contact pads on the surface of the strip. At least one semiconductor die is mounted to the die attach pad, followed by wire bonding the at least one semiconductor die to ones of the contact pads. The at least one semiconductor die, the wire bonds, and the contact pads are covered with an overmold material and the leadframe strip is etched to thereby remove the leadframe strip. The leadless plastic chip carrier is singulated from the leadframe strip.
    Type: Grant
    Filed: January 15, 2004
    Date of Patent: March 7, 2006
    Assignee: ASAT Ltd.
    Inventors: Mohan Kirloskar, Chun Ho Fan, Kwok Cheung Tsang, Kin Pui Kwan
  • Patent number: 6995460
    Abstract: A leadless plastic chip carrier is constructed by half etching one or both sides of the package design onto a leadframe strip so as to create unique design features such as power and/or ground ring surrounding the die attach pad, interlocking rivet head construction for the contact pads, and an interlocking pattern for the die attach pad. After wire bonding and molding, a further etching is performed to isolate and expose contact pads. Singulation of individual chip packages from the leadframe strip is then performed by saw singulation or die punching.
    Type: Grant
    Filed: May 6, 2005
    Date of Patent: February 7, 2006
    Assignee: ASAT Ltd.
    Inventors: Neil McLellan, Chun Ho Fan, Kwok Cheung Tsang, Kin Pui Kwan, Wing Him Lau
  • Patent number: 6989294
    Abstract: A leadless plastic chip carrier is constructed by half etching one or both sides of the package design onto a leadframe strip so as to create unique design features such as power and/or ground ring surrounding the die attach pad, interlocking rivet head construction for the contact pads, and an interlocking pattern for the die attach pad. After wire bonding and molding, a further etching is performed to isolate and expose contact pads. Singulation of individual chip packages from the leadframe strip is then performed by saw singulation or die punching.
    Type: Grant
    Filed: January 28, 2003
    Date of Patent: January 24, 2006
    Assignee: ASAT, Ltd.
    Inventors: Neil McLellan, Chun Ho Fan, Kwok Cheung Tsang, Kin Pui Kwan, Wing Him Lau
  • Patent number: 6946324
    Abstract: A process for fabricating a leadless plastic chip carrier includes laminating a first metal strip to a second metal strip to form a leadframe strip, selectively etching the first metal strip to define at least a row of contact pads, mounting a semiconductor die to either a die attach pad or the second metal strip and wire bonding the semiconductor die to ones of the contact pads, encapsulating a top surface of the leadframe strip in a molding material, removing the second metal strip, thereby exposing the die attach pad and the at least one row of contact pads, and singulating the leadless plastic chip carrier from the leadframe strip.
    Type: Grant
    Filed: October 30, 2003
    Date of Patent: September 20, 2005
    Assignee: Asat Ltd.
    Inventors: Neil McLellan, Chun Ho Fan, Kin Pui Kwan, Wing Him Lau
  • Patent number: 6933594
    Abstract: A leadless plastic chip carrier is constructed by half etching one or both sides of the package design onto a leadframe strip so as to create unique design features such as power and/or ground ring surrounding the die attach pad, interlocking rivet head construction for the contact pads, and an interlocking pattern for the die attach pad. After wire bonding and molding, a further etching is performed to isolate and expose contact pads. Singulation of individual chip packages from the leadframe strip is then performed by saw singulation or die punching.
    Type: Grant
    Filed: March 9, 2001
    Date of Patent: August 23, 2005
    Assignee: ASAT Ltd.
    Inventors: Neil McLellan, Chun Ho Fan, Kwok Cheung Tsang, Kin Pui Kwan, Wing Him Lau
  • Patent number: 6872661
    Abstract: A leadless plastic chip carrier has a plurality of die attach pads on which a singulated semi-conductor die is mounted. At least one row of contact pads circumscribes the plurality of die attach pads and a power/ground ring is intermediate the contact pads and the die attach pads. Wire bonds connect the semiconductor die, the contact pads and the power/ground ring. An overmold covers the semi-conductor die, the die attach pads, the power/ground ring and the contact pads such that each of the die attach pads and the contact pads has one exposed surface.
    Type: Grant
    Filed: December 13, 2002
    Date of Patent: March 29, 2005
    Assignee: ASAT Ltd.
    Inventors: Kin Pui Kwan, Wing Him Lau, Kwok Cheung Tsang, Chun Ho Fan, Neil McLellan
  • Patent number: 6734044
    Abstract: A method of fabricating an integrated circuit package. The method includes providing a first leadframe and a second leadframe, laminating the second leadframe to a portion of the first leadframe in order to create a multi-layer laminated leadframe, and mounting a semiconductor die on another portion of the first leadframe.
    Type: Grant
    Filed: June 10, 2002
    Date of Patent: May 11, 2004
    Assignee: ASAT Ltd.
    Inventors: Chun Ho Fan, Tsui Yee Lin, Kin Pui Kwan, Shui Ming Tse, Wing Him Lau, Shuk Man Wong
  • Patent number: 6635957
    Abstract: A leadless plastic chip carrier has a plurality of die attach pads on which a singulated semi-conductor die is mounted. At least one row of contact pads circumscribes the plurality of die attach pads and a power/ground ring is intermediate the contact pads and the die attach pads. Wire bonds connect the semiconductor die, the contact pads and the power/ground ring. An overmold covers the semiconductor die, the die attach pads, the power/ground ring and the contact pads such that each of the die attach pads and the contact pads has one exposed surface.
    Type: Grant
    Filed: March 9, 2001
    Date of Patent: October 21, 2003
    Assignee: ASAT Ltd.
    Inventors: Kin Pui Kwan, Wing Him Lau, Kwok Cheung Tsang, Chun Ho Fan, Neil Mclellan