Microwave output device and plasma processing apparatus
US11587769B2 · kind B2 · utility
Assignees
Inventors
Key dates
| Filing date | Jul 21, 2021 |
| Grant date | Feb 21, 2023 |
| Priority date | — |
| Expiry date | Aug 24, 2041 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH01J37/32935
- WIPO fieldElectrical machinery, apparatus, energy
- WIPO sectorElectrical engineering
Abstract
A device includes a microwave generator configured to generate a microwave having a bandwidth, an output unit, a directional coupler and a measurer. The microwave generator generates a microwave a power of which is pulse-modulated to be a High level and a Low level. A set carrier pitch is set to satisfy a preset condition. The preset condition includes a condition that a value obtained by dividing a set pulse frequency by the set carrier pitch or a value obtained by dividing the set carrier pitch by the set pulse frequency is not an integer and a condition that an ON-time of the High level is equal to or larger than 50%. The microwave generator averages a first High measurement value and a first Low measurement value in a preset moving average time longer than a sum of the ON-time of the High level at a preset sampling interval.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.