System and method for current-based plasma excursion detection
US8587321B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Sep 24, 2010 |
| Grant date | Nov 19, 2013 |
| Priority date | — |
| Expiry date | Aug 26, 2031 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH01J37/32183
- WIPO fieldElectrical machinery, apparatus, energy
- WIPO sectorElectrical engineering
Abstract
A system and method for the detection of plasma excursions, such as arcs, micro-arcs, or other plasma instability, during plasma processing by directly monitoring RF current just prior to reaching an RF power electrode of a plasma processing chamber is provided. The monitored RF current may be converted to an RF voltage and then passed through a succession of analog filters and amplifiers to provide a plasma excursion signal. The plasma excursion signal is compared to a preset value, and at points where the plasma excursion signal exceeds the preset value, an alarm signal is generated. The alarm signal is then fed back into a system controller so that an operator can be alerted and/or the processing system can be shut down. In one embodiment, the RF current amplified and converted to a digital signal for digital filtering and processing. In certain embodiments, multiple processing regions can be monitored by a single detection control unit.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.