Patents by Inventor Yisuo Li

Yisuo 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).

  • Publication number: 20050280082
    Abstract: A device structure and method for forming graded junction using a implant process. Embodiments of the invention comprise implanting ions into said silicon substrate to form doped regions adjacent to said gate. The orientation of the channel region in the Si crystal structure (channel direction <100>) in combination with the large angle tilt and twist implant process produce doped regions that have a more graded junction. The orientation and implant process creates more channeling of ions. The channeling of ions creates a more graded junction. When implemented on a HV MOS TX, the graded junction of the LDD increases the breakdown voltage. Another embodiment is a FET with an annular shaped channel region.
    Type: Application
    Filed: June 27, 2005
    Publication date: December 22, 2005
    Inventors: Yisuo Li, Xiaohong Jiang, Francis Benistant
  • Patent number: 6972236
    Abstract: A device structure and method for forming graded junction using a implant process. Embodiments of the invention comprise implanting ions into said silicon substrate to form doped regions adjacent to said gate. The orientation of the channel region in the Si crystal structure (channel direction <100>) in combination with the large angle tilt and twist implant process produce doped regions that have a more graded junction. The orientation and implant process creates more channeling of ions. The channeling of ions creates a more graded junction. When implemented on a HV MOS TX, the graded junction of the LDD increases the breakdown voltage. Another embodiment is a FET with an annular shaped channel region.
    Type: Grant
    Filed: January 30, 2004
    Date of Patent: December 6, 2005
    Assignee: Chartered Semiconductor Manufacturing Ltd.
    Inventors: Yisuo Li, Xiaohong Jiang, Francis Benistant
  • Publication number: 20050236677
    Abstract: A device structure and method for forming graded junction using a implant process. Embodiments of the invention comprise implanting ions into said silicon substrate to form doped regions adjacent to said gate. The orientation of the channel region in the Si crystal structure (channel direction <100>) in combination with the large angle tilt and twist implant process produce doped regions that have a more graded junction. The orientation and implant process creates more channeling of ions. The channeling of ions creates a more graded junction. When implemented on a HV MOS TX, the graded junction of the LDD increases the breakdown voltage. Another embodiment is a FET with an annular shaped channel region.
    Type: Application
    Filed: June 28, 2005
    Publication date: October 27, 2005
    Inventors: Yisuo Li, Xiaohong Jiang, Francis Benistant
  • Publication number: 20050239256
    Abstract: A method is described to fabricate a MOSFET device with increased threshold voltage stability. After the pad oxide and pad nitride are deposited on the silicon substrate and shallow trenches are patterned and the pad nitride removed. As+ or P+ species are then implanted using low energy ions of approximately 5 keV into the pad oxide. Conventional As+ or P+ implant follows the shallow implant to form the n-wells. With this procedure of forming a sacrificial shallow implantation oxide layer, surface dopant concentration variation at pad oxide:silicon substrate interface is minimized; and threshold voltage stability variation of the device is significantly decreased.
    Type: Application
    Filed: April 21, 2004
    Publication date: October 27, 2005
    Inventors: Yisuo Li, Francis Benistant, Kim Sik, Zhao Lun
  • Publication number: 20050170595
    Abstract: A device structure and method for forming graded junction using a implant process. Embodiments of the invention comprise implanting ions into said silicon substrate to form doped regions adjacent to said gate. The orientation of the channel region in the Si crystal structure (channel direction <100>) in combination with the large angle tilt and twist implant process produce doped regions that have a more graded junction. The orientation and implant process creates more channeling of ions. The channeling of ions creates a more graded junction. When implemented on a HV MOS TX, the graded junction of the LDD increases the breakdown voltage. Another embodiment is a FET with an annular shaped channel region.
    Type: Application
    Filed: January 30, 2004
    Publication date: August 4, 2005
    Inventors: Yisuo Li, Xiaohong Jiang, Francis Benistant
  • Publication number: 20050156253
    Abstract: A structure and method of reducing junction capacitance of a source/drain region in a transistor. A gate structure is formed over on a first conductive type substrate. We perform a doped depletion region implantation by implanting ions being the second conductive type to the substrate using the gate structure as a mask, to form a doped depletion region beneath and separated from the source/drain regions. The doped depletion regions have an impurity concentration and thickness so that the doped depletion regions are depleted due to a built-in potential creatable between the doped depletion regions and the substrate. The doped depletion region and substrate form depletion regions between the source/drain regions and the doped depletion region. We perform a S/D implant by implanting ions having a second conductivity type into the substrate to form S/D regions. The doped depletion region and depletion regions reduce the capacitance between the source/drain regions and the substrate.
    Type: Application
    Filed: January 21, 2004
    Publication date: July 21, 2005
    Inventors: King Chui, Francis Benistant, Ganesh Samudra, Kian Tee, Yisuo Li, Kum Leong, Kheng Tee
  • Publication number: 20050148125
    Abstract: A method for forming elevated source/drain regions. A gate structure is formed over a substrate. The substrate comprised of silicon. We form a polysilicon layer preferably using PVD or CVD over the gate structure and the substrate. A poly/Si interface is formed between the polysilicon layer and the substrate. We perform a poly/Si interface amorphization implant to amorphize at least the poly/Si interface in the S/D areas and to from an amorphous region. We anneal the substrate to crystallize the amorphous region and the polysilicon layer over the amorphous region to form an elevated silicon region in the source/drain area. Next, source/drain regions in are formed in the elevated silicon regions and the substrate.
    Type: Application
    Filed: January 6, 2004
    Publication date: July 7, 2005
    Inventors: Yisuo Li, Francis Benistant, Kian Tee, King Chui