Method and equipment for plasma processing
US5401356A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Jul 31, 1992 |
| Grant date | Mar 28, 1995 |
| Priority date | — |
| Expiry date | Jul 31, 2012 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH01L21/32137
- WIPO fieldSemiconductors
- WIPO sectorElectrical engineering
Abstract
The amount of dust particles deposited on a semiconductor wafer during plasma etching or CVD in manufacturing a semiconductor integrated circuit is decreased by second plasma generating electrode 28 disposed around a lower electrode 15 in a plasma etching chamber 4a. High frequency voltage is applied to the second plasma generating electrode 18 just before the stop of plasma discharge to form a sub-plasma of high density along the outer periphery of the lower electrode 15, there is formed a sub-potential distribution acting to push out negatively charged dust particles stagnating near the main surface of a semiconductor substrate 7 toward the outer periphery of the wafer. The negatively charged dust particles thus pushed out from the vicinity of the main surface of the wafer 7 are moved to the second plasma generating electrode 28 and exhausted by a vacuum pump through an exhaust port 25.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.