Thin-film capacitor device and RAM device using ferroelectric film
US5889696A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Mar 23, 1998 |
| Grant date | Mar 30, 1999 |
| Priority date | — |
| Expiry date | Mar 23, 2018 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG11C11/22
- WIPO fieldComputer technology
- WIPO sectorElectrical engineering
Abstract
A semiconductor memory device is constituted by arranging a plurality of memory cells in a matrix format, each of which includes a thin-film capacitor having a ferroelectric film and a pair of electrodes facing each other via the ferroelectric film, and a transfer gate transistor connected to the thin film capacitor. A voltage corresponding to the width of a hysteresis curve obtained when the thin-film capacitor is saturated and polarized falls within the range of 5% or higher to 20% or lower of the voltage difference between the positive and negative directions in a writing operation. A remanent polarization amount obtained when the thin-film capacitor is saturated and polarized falls within the range of 5% or higher to 30% or lower of the total polarization amount obtained upon application of a voltage in the writing operation.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.