Method for forming ferrocapacitors and FeRAM devices
US7316980B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Oct 2, 2003 |
| Grant date | Jan 8, 2008 |
| Priority date | — |
| Expiry date | Jun 19, 2024 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH10D1/692
- WIPO fieldSemiconductors
- WIPO sectorElectrical engineering
Abstract
Ferrocapacitors having a vertical structure are formed by a process in which a ferroelectric layer is deposited over an insulator. In a first etching stage, the ferroelectric material is etched to form openings in it, leaving the insulating layer substantially intact. Then a conductive layer is deposited into the openings formed in the ferroelectric layer, forming electrodes on the sides of the openings. Further etching is performed to form gaps in the Al2O3 layer, for making connections to conductive elements beneath it. Thus, by the time the second etching step is performed; there are already electrodes overlying the sides of the ferroelectric material, without insulating fences in between.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.