Patent · US Expired

Methods of forming and reading ferroelectric memory cells

US6522571B2 · kind B2 · utility

2Cited by
1References
30Claims
0Family size

Assignee

Inventor

Key dates

Filing dateJan 15, 2002
Grant dateFeb 18, 2003
Priority date
Expiry dateJan 15, 2022

Classification

  • Technology area (CPC H)Electricity
  • CPC primaryH10B53/30
  • WIPO fieldComputer technology
  • WIPO sectorElectrical engineering

Abstract

Bi-state ferroelectric-MOS (FMOS) capacitors are adapted for use in memory cells of a memory device. Bi-state ferroelectric memory cells have a bottom plate of a capacitor coupled to a first source/drain region of a pass transistor, a gate of the pass transistor coupled to a word line, and a second source/drain region of the pass transistor coupled to a bit line. A plate line is coupled to the top plate of the capacitor to facilitate programming of the polarization state of a ferroelectric portion of the capacitor. The polarization state of the ferroelectric portion of the capacitor causes a depletion or accumulation of electrons in the bottom plate of the capacitor, thus altering its capacitance value. The resulting capacitance value may be sensed without causing a polarization reversal of the ferroelectric portion of the capacitor. Accordingly, bi-state ferroelectric memory cells of the various embodiments function as non-volatile memory cells.

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