Plasma processing apparatus
US6089181A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Jul 21, 1997 |
| Grant date | Jul 18, 2000 |
| Priority date | — |
| Expiry date | Jul 21, 2017 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH01J37/32165
- WIPO fieldElectrical machinery, apparatus, energy
- WIPO sectorElectrical engineering
Abstract
In a plasma etching apparatus, a process gas is supplied into a process chamber and converted into plasma by means of RF discharge, and a semiconductor wafer placed on a lower electrode is etched by the plasma. An RF power supply mechanism is connected to the lower electrode for applying thereto a superposed RF power for forming an RF electric field in the process chamber. The RF power supply mechanism has first and second RF power supplies for respectively oscillating a low frequency RF component and a high frequency RF component having a higher frequency than the low frequency RF component. The high frequency RF component from the second frequency RF component supply has its wave form modulated by a modulator on the basis of the wave form of the low frequency RF component from the first frequency RF power supply. Thereafter, the modulated high frequency RF component and the low frequency RF component are superposed upon each other. The high frequency RF component has a larger amplitude at a negative side peak of the low frequency RF component than at a positive side peak of the low frequency RF component.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.