Patent · US Expired

Ferroelectric memory with two ferroelectric capacitors in memory cell and method of operating same

US6147895A · kind A · utility

121Cited by
15References
15Claims
0Family size

Assignee

Inventor

Key dates

Filing dateJun 4, 1999
Grant dateNov 14, 2000
Priority date
Expiry dateJun 4, 2019

Classification

  • Technology area (CPC G)Physics
  • CPC primaryG11C11/22
  • WIPO fieldComputer technology
  • WIPO sectorElectrical engineering

Abstract

A ferroelectric integrated circuit memory includes a memory cell having a first ferroelectric capacitor, one electrode of which is connected to a first bit line through a first transistor and the other electrode of which is connected to a plate line; and a second ferroelectric capacitor, one electrode of which is connected to a second bit line through a second transistor and the other electrode of which is connected to the plate line. The plate line is parallel to the bit lines. The plate line is at 1/2 Vdd. The cell is written to by driving both bit lines either to Vdd or zero volts. The cell is read by driving one bit line to Vdd and the other to zero volts, and sensing the voltage change on the plate line. A shunt system holds the isolated node to the same voltage as the plate line when the row is not selected, thus providing a ferroelectric memory architecture that is unaffected by changes, such as aging, in the ferroelectric material, and has no disturb voltages.

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