Patent · US Expired

Vertical MOSFET SRAM cell

US7138685B2 · kind B2 · utility

43Cited by
9References
20Claims
0Family size

Assignee

Inventors

Key dates

Filing dateDec 11, 2002
Grant dateNov 21, 2006
Priority date
Expiry dateAug 5, 2023

Classification

  • Technology area (CPC H)Electricity
  • CPC primaryH10D86/201
  • WIPO fieldComputer technology
  • WIPO sectorElectrical engineering

Abstract

A method of forming an SRAM cell device includes the following steps. Form pass gate FET transistors and form a pair of vertical pull-down FET transistors with a first common body and a first common source in a silicon layer patterned into parallel islands formed on a planar insulator. Etch down through upper diffusions between cross-coupled inverter FET transistors to form pull-down isolation spaces bisecting the upper strata of pull-up and pull-down drain regions of the pair of vertical pull-down FET transistors, with the isolation spaces reaching down to the common body strata. Form a pair of vertical pull-up FET transistors with a second common body and a second common drain. Then, connect the FET transistors to form an SRAM cell.

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