Non-destructive read ferroelectric memory cell utilizing the ramer-drab effect
US5729488A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Aug 26, 1994 |
| Grant date | Mar 17, 1998 |
| Priority date | — |
| Expiry date | Aug 26, 2014 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG11C11/22
- WIPO fieldComputer technology
- WIPO sectorElectrical engineering
Abstract
A memory cell is constructed using a ferroelectric capacitor having an insulator formed of a ferroelectric material that has a zero field capacitance which is controllably dependent upon the electrical charging path by which the zero field capacitance is reached. Preferably, the material is characterized by a first zero field capacitance following saturation of the polarization by a first applied voltage applied in a first polarization direction, and a second zero field capacitance following saturation of the polarization by the first applied voltage applied in the first polarization direction followed by partial depolarization by a second voltage applied in a direction opposite to the first polarization direction. A second ferroelectric capacitor or a linear capacitor may be placed in parallel with the ferroelectric capacitor to form a two-capacitor memory cell. Data may be read to or from the capacitor cell without impairing the state of the stored data.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.