Patent · US Expired

Semiconductor device including thin film transistor

US5561308A · kind A · utility

49Cited by
6References
18Claims
0Family size

Assignee

Inventors

Key dates

Filing dateDec 30, 1994
Grant dateOct 1, 1996
Priority date
Expiry dateDec 30, 2014

Classification

  • Technology area (CPC Y)Emerging Cross-Sectional Technologies
  • CPC primaryY10S257/906

Abstract

A semiconductor device comprises a semiconductor substrate of a first conductivity type, a first insulation film formed on the semiconductor substrate, a gate electrode and a second insulation film formed in sequence on the first insulation film, a trench being formed to extend through the second insulation film, the gate electrode and the first insulation film to an interior of the semiconductor substrate. A cylindrical gate insulation film is formed on a surface of the gate electrode which is exposed in the trench. A capacitor insulation film is formed on a surface of the semiconductor substrate exposed in the trench. A cylindrical conductive film is formed inside these insulation films. The cylindrical conductive film includes a region doped with an impurity of the first conductivity type and formed on a surface of the gate insulation film, a region doped with an impurity of a second conductivity type and formed on a surface of the second insulation film and a region doped with an impurity of the second conductivity type and formed on a surface of the capacitor insulation film. A conductive column is formed in a region surrounded by the cylindrical conductive film.

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