Plasma processing apparatus
US6239404A · kind A · utility
32Cited by
4References
8Claims
0Family size
Assignee
Inventors
Key dates
| Filing date | Mar 8, 2000 |
| Grant date | May 29, 2001 |
| Priority date | — |
| Expiry date | Mar 8, 2020 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH01J37/321
- WIPO fieldElectrical machinery, apparatus, energy
- WIPO sectorElectrical engineering
Abstract
Plasma processing apparatus frequently incorporates an antenna fed from a power supply and in this invention a power supply feeds a conventional matching circuit (10), which in turn is connected to the primary (11) of a transformer (12). The antenna (15) is coupled across the secondary winding (13) of the transformer (12) and that winding is tapped to ground at (16). This creates a virtual earth (17) near the mid point of the antenna (15) significantly reducing the variation, along the length of the antenna, in the power supplied to the plasma.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.