Claims
- 1. A ferroelectric memory cell for storing information, said memory cell operating to store said information at a temperature less than a first temperature, said memory cell comprising:a bottom contact; a dielectric layer comprising a ferroelectric material having a Curie point greater than said first temperature and less than 400° C., said ferroelectric material having a remnant polarization below said first temperature, said information being stored by altering said remnant polarization; a top contact, said dielectric layer being sandwiched between said bottom contact and said top contact; and an encapsulating layer comprising an oxygen impermeable material, said encapsulating layer preventing oxygen from entering or leaving said dielectric layer.
- 2. The ferroelectric memory cell of claim 1 wherein said ferroelectric material comprises lead titanate.
- 3. The ferroelectric memory cell of claim 1 wherein said bottom contact comprises a platinum electrode.
- 4. The ferroelectric memory cell of claim 3 wherein said top contact comprises a platinum electrode.
- 5. A ferroelectric memory cell for storing information, said memorv cell operating to store said information at a temperature less than a first temperature, said memorv cell comprising:a bottom contact; a dielectric layer comprising a ferroelectric material having a Curie point greater than said first temperature and less than 400° C., said ferroelectric material having a remnant polarization below said first temperature, said information being stored by altering said remnant polarization; a top contact, said dielectric layer being sandwiched between said bottom contact and said top contact; an encapsulating layer comprising an oxygen impermeable material, said encapsulating layer preventing oxygen from entering or leaving said dielectric layer, wherein said bottom contact comprises a platinum electrode, and wherein said top contact comprises a semiconducting layer and first and second top electrodes, said first and second top electrodes being spaced apart on said semiconducting layer.
- 6. The ferroelectric memory cell of claim 1 wherein said oxygen impermeable material comprises a compound chosen from a group consisting of an oxide of titanium, Al2O3, yttrium stabilized zirconia(YZT), cerium oxide, strontium titanate (SrTiO3), hafnium oxide, strontium oxide, and diamond.
- 7. The ferroelectric memory cell of claim 2 wherein said ferroelectric material is doped with an element having an oxidation state greater than +4.
- 8. The ferroelectric memory cell of claim 7 wherein said doping element is chosen from a group consisting of Nb, Ta, and W.
- 9. The ferroelectric memory cell of claim 7 wherein said doping element is present in a concentration of between 1% and 8%.
- 10. A ferroelectric memory cell for storing information, said memory cell operating to store said information at a temperature less than a first temperature, said memory cell comprising:a bottom contact; a dielectric layer comprising a ferroelectric material having a Curie point greater than said first temperature and less than 400° C., said ferroelectric material having a remnant polarization below said first temperature, said information being stored by altering said remnant polarization; a top contact, said dielectric layer being sandwiched between said bottom contact and said top contact; and an encapsulating layer comprising an oxygen impermeable material, said encapsulating layer preventing oxygen from entering or leaving said dielectric layer, wherein said bottom contact comprises a platinum electrode and wherein said platinum electrode includes a layer of LSCO and a layer of platinum, said layer of LSCO being in contact with said dielectric layer.
- 11. The ferroelectric memory cell of claim 10 wherein said top contact comprises a platinum electrode and wherein said platinum electrode includes a layer of LSCO and a layer of platinum, said layer of LSCO being in contact with said dielectric layer.
RELATED APPLICATIONS
This patent application is a continuation-in-part of U.S. patent application 08/688,064 filed Jul. 29, 1996 now U.S. Pat. No. 5,977,577 which is a continuation in part of U.S. Ser. No. 08/406,376 filed Mar. 17, 1995 now U.S. Pat. 5,541,807, and a continuation in part of U.S. Ser. No. 08/339,839 filed Nov. 15, 1994.
US Referenced Citations (15)
Foreign Referenced Citations (1)
Number |
Date |
Country |
1-109782 |
Apr 1989 |
JP |
Continuation in Parts (3)
|
Number |
Date |
Country |
Parent |
08/688064 |
Jul 1996 |
US |
Child |
09/015373 |
|
US |
Parent |
08/406376 |
Mar 1995 |
US |
Child |
08/688064 |
|
US |
Parent |
08/339839 |
Nov 1994 |
US |
Child |
08/406376 |
|
US |