Patent · US Expired

Non-volatile electronic memory

US4860254A · kind A · utility

79Cited by
4References
8Claims
0Family size

Assignee

Inventors

Key dates

Filing dateJan 27, 1987
Grant dateAug 22, 1989
Priority date
Expiry dateJan 27, 2007

Classification

  • Technology area (CPC G)Physics
  • CPC primaryG11C14/00
  • WIPO fieldComputer technology
  • WIPO sectorElectrical engineering

Abstract

A volatile semiconductor memory module (RAM) is combined with a permanent memory based on an electrically polarizable, preferably ferroelectric, layer within an integrated monolithic module in such a manner that, as a result of a STORE command, the information present in the semiconductor memory is permanently stored by polarization of selected regions of the electrically polarizable layer. In the same way the permanently stored information can be read out again as a result of a RECALL command and returned to the semiconductor memory. Preferably, a ferroelectrically polarizable layer 11 is applied to the semiconductor memory, which layer, in the same way as the semiconductor memory, is provided on its upper side and underside with word and bit lines in the form of strip electrodes, 9,12. The strip electrode system 9 on the underside of the ferroelectric layer 11 simultaneously forms the word or bit line system of the semiconductor memory facing the surface. In this manner each semiconductor memory cell 7 is clearly allocated a non-volatile ferroelectric memory cell 13.

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