Method and apparatus for stabilizing switch-mode powered RF plasma processing
US5747935A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Oct 14, 1994 |
| Grant date | May 5, 1998 |
| Priority date | — |
| Expiry date | Oct 14, 2014 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH02M7/537
- WIPO fieldElectrical machinery, apparatus, energy
- WIPO sectorElectrical engineering
Abstract
Circuitry and techniques designed to allow stable and continuous delivery of alternating power to a processing plasma with switch-mode power supply (16) include a variety of embodiments. Parallel, series, and other circuit elements connected across switching element (7) are tuned so that energy at other than the fundamental frequency is absorbed and dissipated. This energy may be only at the second harmonic or it may be across broad frequency ranges through selecting high impedance at the fundamental frequency and relatively low impedance at other frequencies. In overcoming instabilities, oscillations, and even changing class of operation of the switch-mode power supply, the stabilizing element absorbs the energy to avoid allowing it to affect switch (7) of power supply (16).
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.