Electrode structure for ferroelectric capacitor integrated on silicon
US5798903A · kind A · utility
Assignees
Inventors
Key dates
| Filing date | Dec 26, 1995 |
| Grant date | Aug 25, 1998 |
| Priority date | — |
| Expiry date | Dec 26, 2015 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH10D1/682
- WIPO fieldSemiconductors
- WIPO sectorElectrical engineering
Abstract
A ferroelectric capacitor structure and its method of making in which a ferroelectric stack of two metal-oxide electrodes sandwiching a ferroelectric layer is fabricated on a silicon substrate with an intervening barrier layer, preferably of TiN. In one embodiment, a platinum layer is grown between the TiN and the lower metal-oxide electrode at a sufficiently high temperature that provides crystallographically ordered growth of the ferroelectric stack. In another embodiment, the platinum layer was completely eliminated with the lower electrode being grown directly on the TiN. Although the conventional conductive metal-oxide used in the electrode is lanthanum strontium cobalt oxide (LSCO), lanthanum nickel oxide provides good electrical and lifetime characteristics in a ferroelectric cell. Alternatively, the electrodes can be formed of the rock-salt metal oxides, such as neodymium oxide (NdO).
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.