Patents Assigned to Force-MOS Technology Corporation
  • Patent number: 8461001
    Abstract: A method to manufacture a trenched semiconductor power device including a plurality of trenched gates surrounded by source regions near a top surface of a semiconductor substrate encompassed in body regions. The method for manufacturing the trenched semiconductor power device includes a step of carrying out a tilt-angle implantation through sidewalls of trenches to form drift regions surrounding the trenches at a lower portion of the body regions with higher doping concentration than the epi layer for Rds reduction, and preventing a degraded breakdown voltage due to a thick oxide in lower portion of trench sidewall and bottom. In an exemplary embodiment, the step of carrying out the tilt-angle implantation through the sidewalls of the trenches further includes a step of carrying out a tilt angle implantation with a tilt-angle ranging between 4 to 30 degrees.
    Type: Grant
    Filed: December 9, 2009
    Date of Patent: June 11, 2013
    Assignee: Force-MOS Technology Corporation
    Inventor: Fwu-Iuan Hshieh
  • Patent number: 8389354
    Abstract: A method for operating a semiconductor power device by in a forward conducting mode instead of an avalanche mode during a voltage fly-back during an inductive switch operation for absorbing a transient energy with less stress. The method includes a step of clamping the semiconductor power device with a Zener diode connected between a gate metal and a drain metal of the semiconductor power device to function as a gate-drain (GD) clamp diode with the GD clamp diode having an avalanche voltage lower than a source/drain avalanche voltage of the semiconductor power device whereby as the voltage fly-back inducing a drain voltage increase rapidly reaching the avalanche voltage of the GD clamp diode for generating the forward conducting mode.
    Type: Grant
    Filed: March 19, 2009
    Date of Patent: March 5, 2013
    Assignee: Force-MOS Technology Corporation
    Inventor: Fwu-Iuan Hshieh
  • Patent number: 8159021
    Abstract: A trenched semiconductor power device includes a plurality of trenched gates surrounded by source regions near a top surface of a semiconductor substrate encompassed in body regions. The trenched semiconductor power device further includes a first epitaxial layer above heavily doped substrate and beyond the trench bottom and a second epitaxial layer above said first epitaxial layer wherein a resistivity N1 of said first epitaxial layer is greater than a resistivity N2 of said second epitaxial layer represented by a functional relationship of N1>N2. In an exemplary embodiment, each of the trenched gates include an upper gate portion and lower gate portion formed with single polysilicon deposition processes wherein the lower gate portion is surrounded with a lower gate insulation layer having a greater thickness than an upper gate insulation layer surrounding the upper gate portion.
    Type: Grant
    Filed: February 20, 2008
    Date of Patent: April 17, 2012
    Assignee: Force-MOS Technology Corporation
    Inventor: Fwu-Iuan Hshieh
  • Patent number: 7960787
    Abstract: A semiconductor power device formed on a semiconductor substrate of a first conductivity type wherein the semiconductor power device includes trench gates surrounded by body regions of a second conductivity type encompassing source regions of the first conductivity type therein. The semiconductor power device further includes trench contact structure having a plurality of trench contacts with trenches extended into the body regions for as source-body contacts and extended into the trench gates as gate contact. The semiconductor power device further includes a termination area wherein a plurality of the trench gate contacts are electrically connected to the source-body contacts.
    Type: Grant
    Filed: November 7, 2008
    Date of Patent: June 14, 2011
    Assignee: Force-MOS Technology Corporation
    Inventor: Fwa-Iuan Hshieh
  • Patent number: 7750398
    Abstract: A trench MOSFET (Metal-Oxide-Semiconductor Field Effect Transistor) with a trench termination, including a substrate including a drain region which is strongly doped and a doping epi layer region, which is weekly doped the same type as the drain region, on the drain region; a plurality of source and body regions formed in the epi layer; a metal layer including a plurality of metal layer regions which are connected to respective source and body, and gate regions forming metal connections of the MOSFET; a plurality of metal contact plugs connected to respective metal layer regions; a plurality of gate trenches filled with polysilicon to form a plurality of trenched gates on top of epi layer; an insulating layer deposited on the epi layer formed underneath the metal layer with a plurality of metal contact holes therein for contacting respective source and body regions; a margin terminating gate trench which is around the gate trenches; and a margin terminating active region which is formed underneath the margin
    Type: Grant
    Filed: September 26, 2007
    Date of Patent: July 6, 2010
    Assignee: Force-MOS Technology Corporation
    Inventor: Fwu-Iuan Hshieh
  • Patent number: 7646058
    Abstract: A vertical semiconductor power device includes a plurality of semiconductor power cells connected to a bottom electric terminal disposed on a bottom surface of a semiconductor substrate and at least a top electrical terminal disposed on a top surface of the substrate and connected to the semiconductor power cells. The top electrical terminal further includes a solderable front metal for soldering to a conductor for providing an electric connection therefrom. In an exemplary embodiment, the conductor soldering to the solderable front metal includes a conductor of a high-heat-conductivity metal plate. In another exemplary embodiment, the conductor soldering to the solderable front metal includes a copper plate. In another exemplary embodiment, the solderable front metal includes a Ti/Ni/Au front metal. In another exemplary embodiment, the solderable front metal includes a Ti/Ni/Ag front metal.
    Type: Grant
    Filed: June 5, 2007
    Date of Patent: January 12, 2010
    Assignee: Force-MOS Technology Corporation
    Inventor: Fwu-Iuan Hshieh
  • Patent number: 7511357
    Abstract: A MOSFET device that includes a first Zener diode connected between a gate metal and a drain metal of said semiconductor power device for functioning as a gate-drain (GD) clamp diode. The GD clamp diode includes multiple back-to-back doped regions in a polysilicon layer doped with dopant ions of a first conductivity type next to a second conductivity type disposed on an insulation layer above the MOSFET device, having an avalanche voltage lower than a source/drain avalanche voltage of the MOSFET device wherein the Zener diode is insulated from a doped region of the MOSFET device for preventing a channeling effect.
    Type: Grant
    Filed: April 20, 2007
    Date of Patent: March 31, 2009
    Assignee: Force-MOS Technology Corporation
    Inventor: Fwu-Iuan Hshieh
  • Publication number: 20090057756
    Abstract: A trench MOSFET (Metal-Oxide-Semiconductor Field Effect Transistor) with a trench termination, including a substrate including a drain region which is strongly doped and a doping epi layer region, which is weekly doped the same type as the drain region, on the drain region; a plurality of source and body regions formed in the epi layer; a metal layer including a plurality of metal layer regions which are connected to respective source and body, and gate regions forming metal connections of the MOSFET; a plurality of metal contact plugs connected to respective metal layer regions; a plurality of gate trenches filled with polysilicon to form a plurality of trenched gates on top of epi layer; an insulating layer deposited on the epi layer formed underneath the metal layer with a plurality of metal contact holes therein for contacting respective source and body regions; a margin terminating gate trench which is around the gate trenches; and a margin terminating active region which is formed underneath the margin
    Type: Application
    Filed: September 26, 2007
    Publication date: March 5, 2009
    Applicant: FORCE-MOS TECHNOLOGY CORPORATION
    Inventor: Fwu-Iuan Hshieh