Patents by Inventor Liang Chao

Liang Chao 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: 8927401
    Abstract: A trench Schottky diode and its manufacturing method are provided. The trench Schottky diode includes a semiconductor substrate having therein a plurality of trenches, a gate oxide layer, a polysilicon structure, a guard ring and an electrode. At first, the trenches are formed in the semiconductor substrate by an etching step. Then, the gate oxide layer and the polysilicon structure are formed in the trenches and protrude above a surface of the semiconductor substrate. The guard ring is formed to cover a portion of the resultant structure. At last, the electrode is formed above the guard ring and the other portion not covered by the guard ring. The protruding gate oxide layer and the protruding polysilicon structure can avoid cracks occurring in the trench structure.
    Type: Grant
    Filed: January 7, 2013
    Date of Patent: January 6, 2015
    Assignee: PFC Device Corp.
    Inventors: Kou-Liang Chao, Hung-Hsin Kuo, Tse-Chuan Su, Mei-Ling Chen
  • Patent number: 8921949
    Abstract: A MOS P-N junction diode includes a semiconductor substrate, a mask layer, a guard ring, a gate oxide layer, a polysilicon structure, a central conductive layer, a silicon nitride layer, a metal diffusion layer, a channel region, and a metal sputtering layer. For manufacturing the MOS P-N junction diode, a mask layer is formed on a semiconductor substrate. A gate oxide layer is formed on the semiconductor substrate, and a polysilicon structure is formed on the gate oxide layer. A guard ring, a central conductive layer and a channel region are formed in the semiconductor substrate. A silicon nitride layer is formed on the central conductive layer. A metal diffusion layer is formed within the guard ring and the central conductive layer. Afterwards, a metal sputtering layer is formed, and the mask layer is partially exposed.
    Type: Grant
    Filed: December 26, 2012
    Date of Patent: December 30, 2014
    Assignee: PFC Device Corp.
    Inventors: Kou-Liang Chao, Hung-Hsin Kuo, Tse-Chuan Su, Mei-Ling Chen
  • Patent number: 8890279
    Abstract: A trench Schottky rectifier device includes a substrate having a first conductivity type, a plurality of trenches formed in the substrate, and an insulating layer formed on sidewalls of the trenches. The trenches are filled with conductive structure. There is an electrode overlying the conductive structure and the substrate, and thus a Schottky contact forms between the electrode and the substrate. A plurality of embedded doped regions having a second conductivity type are formed in the substrate and located under the trenches. Each doped region and the substrate form a PN junction to pinch off current flowing toward the Schottky contact so as to suppress current leakage.
    Type: Grant
    Filed: November 15, 2013
    Date of Patent: November 18, 2014
    Assignee: PFC Device Corp.
    Inventors: Kou-Liang Chao, Mei-Ling Chen, Tse-Chuan Su, Hung-Hsin Kuo
  • Publication number: 20140308799
    Abstract: A trench isolation metal-oxide-semiconductor (MOS) P-N junction diode device and a manufacturing method thereof are provided. The trench isolation MOS P-N junction diode device is a combination of an N-channel MOS structure and a lateral P-N junction diode, wherein a polysilicon-filled trench oxide layer is buried in the P-type structure to replace the majority of the P-type structure. As a consequence, the trench isolation MOS P-N junction diode device of the present invention has the benefits of the Schottky diode and the P-N junction diode. That is, the trench isolation MOS P-N junction diode device has rapid switching speed, low forward voltage drop, low reverse leakage current and short reverse recovery time.
    Type: Application
    Filed: May 26, 2014
    Publication date: October 16, 2014
    Applicant: PFC DEVICE CORP.
    Inventors: Mei-Ling Chen, Hung-Hsin Kuo, Kuo-Liang Chao
  • Patent number: 8853748
    Abstract: A method for manufacturing a rectifier with a vertical MOS structure is provided. A first trench structure and a first mask layer are formed at a first side of the semiconductor substrate. A second trench structure is formed in the second side of the semiconductor substrate. A gate oxide layer, a polysilicon structure and a metal sputtering layer are sequentially formed on the second trench structure. The rectifier further includes a wet oxide layer and a plurality of doped regions. The wet oxide layer is formed on a surface of the first multi-trench structure and in the semiconductor substrate. The doping regions are formed on a region between the semiconductor substrate and the second trench structure, and located beside the mask layer. The metal sputtering layer is formed on the first mask layer corresponding to the first trench structure.
    Type: Grant
    Filed: January 8, 2014
    Date of Patent: October 7, 2014
    Assignee: PFC Device Corp.
    Inventors: Kuo-Liang Chao, Mei-Ling Chen, Hung-Hsin Kuo
  • Patent number: 8809946
    Abstract: A wide trench termination structure for semiconductor device includes a wide trench structure defined on a semiconductor substrate and having a width larger than that of narrow trench structures on an active region of the semiconductor device, an oxide layer arranged on an inner face of the wide trench structure, at least one trench polysilicon layer arranged on the oxide layer and on inner sidewall of the wide trench structure, a metal layer arranged on the oxide layer not covered by the trench polysilicon layer and on the trench polysilicon layer, and a field oxide layer arranged on the semiconductor substrate and outside the wide trench structure.
    Type: Grant
    Filed: January 9, 2013
    Date of Patent: August 19, 2014
    Assignee: PFC Device Corp.
    Inventors: Hung-Hsin Kuo, Mei-Ling Chen, Kuo-Liang Chao
  • Patent number: 8796808
    Abstract: A MOS P-N junction Schottky diode device includes a substrate having a first conductivity type, a field oxide structure defining a trench structure, a gate structure formed in the trench structure and a doped region having a second conductivity type adjacent to the gate structure in the substrate. An ohmic contact and a Schottky contact are formed at different sides of the gate structure. The method for manufacturing such diode device includes several ion-implanting steps to form several doped sub-regions with different implantation depths to constitute the doped regions. The formed MOS P-N junction Schottky diode device has low forward voltage drop, low reverse leakage current, fast reverse recovery time and high reverse voltage tolerance.
    Type: Grant
    Filed: April 21, 2009
    Date of Patent: August 5, 2014
    Assignee: PFC Device Corp.
    Inventors: Kuo-Liang Chao, Hung-Hsin Kuo, Tse-Chuan Su
  • Publication number: 20140167205
    Abstract: A super junction for semiconductor device includes a silicon substrate with a first conductive type epitaxial layer, a plurality of highly-doped second conductive type columns formed in the first conductive type epitaxial layer, and a plurality of lightly-doped (first conductive type or second conductive type) side walls formed on outer surfaces of the highly-doped second conductive type. The semiconductor device is super-junction MOSFET, super junction MOSFET, super junction Schottky rectifier, super junction IGBT, thyristor or super junction diode.
    Type: Application
    Filed: December 12, 2013
    Publication date: June 19, 2014
    Applicant: PFC DEVICE HOLDINGS LIMITED
    Inventors: Paul Chung-Chen CHANG, Kuo-Liang CHAO, Mei-Ling CHEN, Lung-Ching KAO
  • Patent number: 8753963
    Abstract: A multi-trench termination structure for semiconductor device is disclosed, where the semiconductor device includes a semiconductor substrate and an active structure region. The multi-trench termination structure includes multiple trenches defined on an exposed face of the semiconductor substrate, a first mask layer formed on a partial exposed surface of the semiconductor substrate and corresponding to a termination structure region of the semiconductor device, a gate insulation layer formed in the trenches, a conductive layer formed on the gate insulation layer and protruding out of the exposed surface of the semiconductor substrate, and a metal layer formed over the first mask layer and conductive layer on the termination structure region of the semiconductor device.
    Type: Grant
    Filed: September 26, 2013
    Date of Patent: June 17, 2014
    Assignee: PFC Device Corp.
    Inventors: Lung-Ching Kao, Mei-Ling Chen, Kuo-Liang Chao, Hung-Hsin Kuo
  • Patent number: 8735228
    Abstract: A trench isolation metal-oxide-semiconductor (MOS) P-N junction diode device and a manufacturing method thereof are provided. The trench isolation MOS P-N junction diode device is a combination of an N-channel MOS structure and a lateral P-N junction diode, wherein a polysilicon-filled trench oxide layer is buried in the P-type structure to replace the majority of the P-type structure. As a consequence, the trench isolation MOS P-N junction diode device of the present invention has the benefits of the Schottky diode and the P-N junction diode. That is, the trench isolation MOS P-N junction diode device has rapid switching speed, low forward voltage drop, low reverse leakage current and short reverse recovery time.
    Type: Grant
    Filed: September 5, 2013
    Date of Patent: May 27, 2014
    Assignee: PFC Device Corp.
    Inventors: Mei-Ling Chen, Hung-Hsin Kuo, Kuo-Liang Chao
  • Patent number: 8728878
    Abstract: A MOS P-N junction diode device includes a substrate having a first conductivity type, a field oxide structure defining a trench structure, a gate structure formed in the trench structure and a doped region having a second conductivity type adjacent to the gate structure in the substrate. The method for manufacturing such diode device includes several ion-implanting steps. After the gate structure is formed by isotropic etching using a patterned photo-resist layer as a mask, an ion-implanting step is performed using the patterned photo-resist layer as a mask to form a deeper doped sub-region. Then, another ion-implanting step is performed using the gate structure as a mask to form a shallower doped sub-region between the gate structure and the deeper doped sub-region. The formed MOS P-N junction diode device has low forward voltage drop, low reverse leakage current, fast reverse recovery time and high reverse voltage tolerance.
    Type: Grant
    Filed: January 11, 2013
    Date of Patent: May 20, 2014
    Assignee: PFC Device Corp.
    Inventors: Kuo-Liang Chao, Hung-Hsin Kuo, Tse-Chuan Su
  • Publication number: 20140131793
    Abstract: A method for manufacturing a rectifier with a vertical MOS structure is provided. A first trench structure and a first mask layer are formed at a first side of the semiconductor substrate. A second trench structure is formed in the second side of the semiconductor substrate. A gate oxide layer, a polysilicon structure and a metal sputtering layer are sequentially formed on the second trench structure. The rectifier further includes a wet oxide layer and a plurality of doped regions. The wet oxide layer is formed on a surface of the first multi-trench structure and in the semiconductor substrate. The doping regions are formed on a region between the semiconductor substrate and the second trench structure, and located beside the mask layer. The metal sputtering layer is formed on the first mask layer corresponding to the first trench structure.
    Type: Application
    Filed: January 8, 2014
    Publication date: May 15, 2014
    Applicant: PFC DEVICE CORP.
    Inventors: Kuo-Liang Chao, Mei-Ling Chen, Hung-Hsin Kuo
  • Patent number: 8704298
    Abstract: A MOS diode includes a substrate with a mesa, a P-type semiconductor region with etched shallow trench surrounding the mesa, that cause an increasing metal contact area to reduce Vf value, a gate oxide layer arranged on the mesa, a polysilicon layer arranged on the gate oxide layer, and a shielding oxide layer arranged on the polysilicon layer. The termination structure includes a trench, an oxide layer arranged at least within the trench, at least one sidewall polysilicon layer arranged on the oxide layer within the trench. In the MOS diode, the shielding oxide layer is thicker than the gate oxide layer to prevent leaking current. The oxide layer and the sidewall polysilicon layer can enhance the reverse voltage tolerance of the MOS diode. A metal layer covers the polysilicon region, shielding oxide layer, semiconductor regions with etched shallow trench, termination region and some parts outside the termination region.
    Type: Grant
    Filed: March 14, 2013
    Date of Patent: April 22, 2014
    Assignee: PFC Device Corp.
    Inventors: Kuo-Liang Chao, Mei-Ling Chen, Lung-Ching Kao, Hung-Hsin Kuo
  • Patent number: 8680590
    Abstract: A multi-trench termination structure for semiconductor device is disclosed, where the semiconductor device includes a semiconductor substrate and an active structure region. The multi-trench termination structure includes multiple trenches defined on an exposed face of the semiconductor substrate, a first mask layer formed on a partial exposed surface of the semiconductor substrate and corresponding to a termination structure region of the semiconductor device, a gate insulation layer formed in the trenches, a conductive layer formed on the gate insulation layer and protruding out of the exposed surface of the semiconductor substrate, and a metal layer formed over the first mask layer and conductive layer on the termination structure region of the semiconductor device.
    Type: Grant
    Filed: March 2, 2012
    Date of Patent: March 25, 2014
    Assignee: PFC Device Corp.
    Inventors: Lung-Ching Kao, Mei-Ling Chen, Kuo-Liang Chao, Hung-Hsin Kuo
  • Publication number: 20140077328
    Abstract: A trench Schottky rectifier device includes a substrate having a first conductivity type, a plurality of trenches formed in the substrate, and an insulating layer formed on sidewalls of the trenches. The trenches are filled with conductive structure. There is an electrode overlying the conductive structure and the substrate, and thus a Schottky contact forms between the electrode and the substrate. A plurality of embedded doped regions having a second conductivity type are formed in the substrate and located under the trenches. Each doped region and the substrate form a PN junction to pinch off current flowing toward the Schottky contact so as to suppress current leakage.
    Type: Application
    Filed: November 15, 2013
    Publication date: March 20, 2014
    Applicant: PFC DEVICE CORP.
    Inventors: Kou-Liang CHAO, Mei-Ling CHEN, Tse-Chuan SU, Hung-Hsin KUO
  • Patent number: 8664701
    Abstract: A method for manufacturing a rectifier with a vertical MOS structure is provided. A first trench structure and a first mask layer are formed at a first side of the semiconductor substrate. A second trench structure is formed in the second side of the semiconductor substrate. A gate oxide layer, a polysilicon structure and a metal sputtering layer are sequentially formed on the second trench structure. The rectifier further includes a wet oxide layer and a plurality of doped regions. The wet oxide layer is formed on a surface of the first multi-trench structure and in the semiconductor substrate. The doping regions are formed on a region between the semiconductor substrate and the second trench structure, and located beside the mask layer. The metal sputtering layer is formed on the first mask layer corresponding to the first trench structure.
    Type: Grant
    Filed: April 13, 2012
    Date of Patent: March 4, 2014
    Assignee: PFC Device Corp.
    Inventors: Kuo-Liang Chao, Mei-Ling Chen, Hung-Hsin Kuo
  • Publication number: 20140030882
    Abstract: A multi-trench termination structure for semiconductor device is disclosed, where the semiconductor device includes a semiconductor substrate and an active structure region. The multi-trench termination structure includes multiple trenches defined on an exposed face of the semiconductor substrate, a first mask layer formed on a partial exposed surface of the semiconductor substrate and corresponding to a termination structure region of the semiconductor device, a gate insulation layer formed in the trenches, a conductive layer formed on the gate insulation layer and protruding out of the exposed surface of the semiconductor substrate, and a metal layer formed over the first mask layer and conductive layer on the termination structure region of the semiconductor device.
    Type: Application
    Filed: September 26, 2013
    Publication date: January 30, 2014
    Applicant: PFC DEVICE CORP.
    Inventors: Lung-Ching KAO, Mei-Ling CHEN, Kuo-Liang CHAO, Hung-Hsin KUO
  • Publication number: 20140004681
    Abstract: A trench isolation metal-oxide-semiconductor (MOS) P-N junction diode device and a manufacturing method thereof are provided. The trench isolation MOS P-N junction diode device is a combination of an N-channel MOS structure and a lateral P-N junction diode, wherein a polysilicon-filled trench oxide layer is buried in the P-type structure to replace the majority of the P-type structure. As a consequence, the trench isolation MOS P-N junction diode device of the present invention has the benefits of the Schottky diode and the P-N junction diode. That is, the trench isolation MOS P-N junction diode device has rapid switching speed, low forward voltage drop, low reverse leakage current and short reverse recovery time.
    Type: Application
    Filed: September 5, 2013
    Publication date: January 2, 2014
    Applicant: PFC DEVICE CORP.
    Inventors: Mei-Ling Chen, Hung-Hsin Kuo, Kuo-Liang Chao
  • Patent number: 8618626
    Abstract: A trench Schottky rectifier device includes a substrate having a first conductivity type, a plurality of trenches formed in the substrate, and an insulating layer formed on sidewalls of the trenches. The trenches are filled with conductive structure. There is an electrode overlying the conductive structure and the substrate, and thus a Schottky contact forms between the electrode and the substrate. A plurality of embedded doped regions having a second conductivity type are formed in the substrate and located under the trenches. Each doped region and the substrate form a PN junction to pinch off current flowing toward the Schottky contact so as to suppress current leakage.
    Type: Grant
    Filed: October 12, 2010
    Date of Patent: December 31, 2013
    Assignee: PFC Device Corporation
    Inventors: Kou-Liang Chao, Mei-Ling Chen, Tse-Chuan Su, Hung-Hsin Kuo
  • Patent number: 8558315
    Abstract: A trench isolation metal-oxide-semiconductor (MOS) P-N junction diode device and a manufacturing method thereof are provided. The trench isolation MOS P-N junction diode device is a combination of an N-channel MOS structure and a lateral P-N junction diode, wherein a polysilicon-filled trench oxide layer is buried in the P-type structure to replace the majority of the P-type structure. As a consequence, the trench isolation MOS P-N junction diode device of the present invention has the benefits of the Schottky diode and the P-N junction diode. That is, the trench isolation MOS P-N junction diode device has rapid switching speed, low forward voltage drop, low reverse leakage current and short reverse recovery time.
    Type: Grant
    Filed: July 26, 2011
    Date of Patent: October 15, 2013
    Assignee: PFC Device Corporation
    Inventors: Mei-Ling Chen, Hung-Hsin Kuo, Kou-Liang Chao