Patent · US Expired

Oxide-isolated source/drain transistor

US5043778A · kind A · utility

44Cited by
7References
48Claims
0Family size

Assignee

Inventors

Key dates

Filing dateAug 25, 1988
Grant dateAug 27, 1991
Priority date
Expiry dateAug 25, 2008

Classification

  • Technology area (CPC Y)Emerging Cross-Sectional Technologies
  • CPC primaryY10S257/90
  • WIPO fieldSemiconductors
  • WIPO sectorElectrical engineering

Abstract

A MOS bulk device having source/drain-contact regions 36 which are almost completely isolated by a dielectric 35. These "source/drain" regions 36 formed by using a silicon etch to form a recess, limiting the etched recess with oxide, and backfilling with polysilicon. A short isotropic oxide etch, followed by a polysilicon filament deposition, then makes contact between the oxide-isolated source/drain-contact regions 36 and the channel region 33 of the active device. Outdiffusion through the small area of this contact will form small diffusioins 44 in silicon, which act as the electrically effective source/drain regions. Use of sidewall nitride filaments 30 on the gate permits the silicon etch step to be self-aligned.

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