Patent · US Expired

Static random access memory (SRAM) including Fermi-threshold field effect transistors

US5222039A · kind A · utility

11Cited by
28References
17Claims
0Family size

Assignee

Inventor

Key dates

Filing dateNov 28, 1990
Grant dateJun 22, 1993
Priority date
Expiry dateNov 28, 2010

Classification

  • Technology area (CPC G)Physics
  • CPC primaryG11C11/412
  • WIPO fieldComputer technology
  • WIPO sectorElectrical engineering

Abstract

A static random access memory (SRAM) cell uses a pair of conventional cross-coupled MOSFET devices including an inversion layer, and a pair of inversion-free Fermi threshold FET devices, of the same conductivity type as the cross-coupled transistor pair, for resistive loads. The Fermi-FETs provide a high valued resistor, the value of which is independent of current variations and which is easily fabricated without the need to control polycrystalline silicon grain size. The Fermi-FETs may also provide temperature compensation of the SRAM cell so that it is operable over a wide range of temperature. Fermi-FETs may also be used for the pass transistors of the SRAM cell with the Fermi-FET's low gate capacitance minimizing the loading of the word line. A high speed, dense SRAM cell is provided. The Fermi-FET may also be used in other applications which require low input capacitance, high value constant resistance and temperature compensation.

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