Methods for forming and integrated circuit structures containing enhanced-surface-area conductive layers
US6482736B1 · kind B1 · utility
Assignee
Inventors
Key dates
| Filing date | Jun 8, 2000 |
| Grant date | Nov 19, 2002 |
| Priority date | — |
| Expiry date | Jun 8, 2020 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH10D1/682
Abstract
An enhanced-surface-area conductive layer compatible with high-dielectric constant materials is created by forming a film or layer having at least two phases, at least one of which is electrically conductive. The film may be formed in any convenient manner, such as by chemical vapor deposition techniques, which may be followed by an anneal to better define and/or crystallize the at least two phases. The film may be formed over an underlying conductive layer. At least one of the at least two phases is selectively removed from the film, such as by an etch process that preferentially etches at least one of the at least two phases so as to leave at least a portion of the electrically conductive phase. Ruthenium and ruthenium oxide, both conductive, may be used for the two or more phases. Iridium and its oxide, rhodium and its oxide, and platinum and platinum-rhodium may also be used. A wet etchant comprising ceric ammonium nitrate and acetic acid may be used. In the case of this etchant and a ruthenium/riruthenium oxide film, the etchant preferentially removes the ruthenium phase, leaving a pitted or “islanded” surface of ruthenium oxide physically and electrically connecte…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.