Patent · US Expired

Trench gate fermi-threshold field effect transistors

US6555872B1 · kind B1 · utility

34Cited by
22References
41Claims
0Family size

Assignee

Inventor

Key dates

Filing dateNov 22, 2000
Grant dateApr 29, 2003
Priority date
Expiry dateJan 6, 2021

Classification

  • Technology area (CPC H)Electricity
  • CPC primaryH10D30/608
  • WIPO fieldSemiconductors
  • WIPO sectorElectrical engineering

Abstract

Field effect transistors include a semiconductor substrate of first conductivity type having a surface. A tub region of second conductivity type is in the semiconductor substrate at the surface and extends into the semiconductor substrate a first depth from the first surface. Spaced apart source and drain regions of the second conductivity type are included in the tub region of second conductivity type at the surface, to define single conductivity junctions of the second conductivity type with the tub region of second conductivity type. The spaced apart source and drain regions extend into the tub region a second depth that is less than the first depth. A trench is included in the tub region, between the spaced apart source and drain regions, and extending from the surface into the tub region to a third depth that is more than the second depth but is less than the first depth. An insulated gate electrode is included in the trench. Source and drain electrodes are provided on the surface that electrically contact the source and drain regions respectively. These field effect transistors may be fabricated by forming a tub region of second conductivity type in a semiconductor substrate …

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.