Process for controlling the wall inclination of a plasma etched via hole
US3986912A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Sep 4, 1975 |
| Grant date | Oct 19, 1976 |
| Priority date | — |
| Expiry date | Sep 4, 1995 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH01L21/76804
- WIPO fieldSemiconductors
- WIPO sectorElectrical engineering
Abstract
A process is disclosed for controlling the inclination of the side wall of a layer of sputtered quartz etched by a reactive plasma etching technique. The process consists of coating a selected fractional area of the backside of a silicon wafer to be etched, with a material resistant to plasma etching. Then coating the front side of the wafer bearing a layer of sputtered quartz, with a coating of organic material having a temperature dependent plasma etching rate, so as to delineate locations in the sputtered quartz layer for the formation of via holes. Next, exposing the wafer in a reactive plasma etching chamber. The inclination of the side wall of the via hole etched in the sputtered quartz layer by the reactive plasma etching step, may be controlled through the correlation of the selected area of exposure of the backside of the wafer, to the operating temperature under which the etching process proceeds which, in turn, governs the rate at which the organic layer is etched around the periphery of the via hole.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.