Patents Assigned to Siliconix inorporated
  • Publication number: 20030032247
    Abstract: Trench MOSFETs including active corner regions and a thick insulative layer at the bottom of the trench are disclosed, along with methods of fabricating such MOSFETs. In an exemplary embodiment, the trench MOSFET includes a thick insulative layer centrally located at the bottom of the trench. A thin gate insulative layer lines the sidewall and a peripheral portion of the bottom surface of the trench. A gate fills the trench, adjacent to the gate insulative layer. The gate is adjacent to the sides and top of the thick insulative layer. The thick insulative layer separates the gate from the drain conductive region at the bottom of the trench yielding a reduced gate-to-drain capacitance making such MOSFETs suitable for high frequency applications.
    Type: Application
    Filed: August 10, 2001
    Publication date: February 13, 2003
    Applicant: Siliconix inorporated
    Inventors: Mohamed N. Darwish, Frederick P. Giles, Kam Hong Lui, Kuo-In Chen, Kyle Terrill
  • Patent number: 5558313
    Abstract: To reduce susceptibility to punchthrough, the channel region of the P body region of a trench field effect transistor is formed in a layer of lightly doped epitaxial silicon. As a result, the channel region has less counterdoping from the background epitaxial silicon and has a greater net P type dopant concentration. Due to the higher net dopant concentration of the P body region, the depletion regions on either side of the P body region expand less far inward through the P body region at a given voltage, thereby rendering the transistor less susceptible to source-to-drain punchthrough. To maintain a low R.sub.DSon, the relatively high conductivity of an accumulation region formed along a sidewall of the trench of the transistor when the transistor is on is used to form a conductive path from the channel region to an underlying relatively highly conductive layer upon which the lightly doped epitaxial layer is formed.
    Type: Grant
    Filed: February 10, 1995
    Date of Patent: September 24, 1996
    Assignee: Siliconix inorporated
    Inventors: Fwu-Iuan Hshieh, Mike F. Chang