Retrograde openings in thin films
US6355567B1 · kind B1 · utility
Assignee
Inventors
Key dates
| Filing date | Jun 30, 1999 |
| Grant date | Mar 12, 2002 |
| Priority date | — |
| Expiry date | Jun 30, 2019 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH01L21/31116
- WIPO fieldSemiconductors
- WIPO sectorElectrical engineering
Abstract
Retrograde openings in thin films and the process for forming the same. The openings may include conductive materials formed within the openings to serve as a wiring pattern which includes wires having tapered cross sections. The process involves a two-step etching procedure for forming a retrograde opening within a film having a gradient of a characteristic that influences the etch rate for a chosen etchant species. An opening is first formed within the film by an anisotropic etch process. The opening is then converted to an opening including retrograde features by an isotropic etch process which is selective to the characteristic. Thereafter, the retrograde opening is filled with a conductive material, in one case, by electroplating or other deposition techniques.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.