Reducing speckle in an excimer light source
US10451890B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Jan 16, 2017 |
| Grant date | Oct 22, 2019 |
| Priority date | — |
| Expiry date | Jan 16, 2037 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH01S3/0057
- WIPO fieldOptics
- WIPO sectorInstruments
Abstract
A method includes: producing a light beam made up of pulses having a wavelength in the deep ultraviolet range, each pulse having a first temporal coherence defined by a first temporal coherence length and each pulse being defined by a pulse duration; for one or more pulses, modulating the optical phase over the pulse duration of the pulse to produce a modified pulse having a second temporal coherence defined by a second temporal coherence length that is less than the first temporal coherence length of the pulse; forming a light beam of pulses at least from the modified pulses; and directing the formed light beam of pulses toward a substrate within a lithography exposure apparatus.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.