Process for removing contaminant
US4654115A · kind A · utility
14Cited by
5References
11Claims
0Family size
Assignee
Inventors
Key dates
| Filing date | Apr 8, 1986 |
| Grant date | Mar 31, 1987 |
| Priority date | — |
| Expiry date | Apr 8, 2006 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH05K2203/095
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
Contaminant is removed from holes by etching in a gaseous plasma by first removing contaminant from the vicinity of the edges of the hole. Next, a mask is provided in the vicinity of the edges to prevent etching by contacting with a gaseous plasma which is different from the gaseous plasma employed in the first etching step. The holes are then etched in a gaseous plasma to remove contaminant from the interior of the holes in the vicinity of the center of the holes, whereby the mask protects the edges from being etched.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.