Lithographic apparatus and method
US10627724B2 · kind B2 · utility
Assignees
Inventors
Key dates
| Filing date | Aug 23, 2016 |
| Grant date | Apr 21, 2020 |
| Priority date | — |
| Expiry date | Dec 14, 2036 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG03F7/70533
- WIPO fieldOptics
- WIPO sectorInstruments
Abstract
A method of controlling output of a radiation source, the method including: periodically monitoring an output energy of the radiation source; determining a difference between a reference energy signal and the monitored output energy; determining a feedback value; determining a desired output energy of the radiation source for a subsequent time period; and controlling an input parameter of the radiation source in dependence on the determined desired output energy during the subsequent time period. If the magnitude of the determined difference between the monitored output energy of the radiation source and the reference energy signal exceeds a threshold value: the determined difference does not contribute to the feedback value; and the determined difference is spread over the subsequent time period according to a reference energy signal adjustment profile and the reference energy signal adjustment profile is added to the reference energy signal for the subsequent time period.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.