Optical collector for collecting extreme ultraviolet radiation, method for operating such an optical collector, and EUV source with such a collector
US9513569B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Mar 16, 2011 |
| Grant date | Dec 6, 2016 |
| Priority date | — |
| Expiry date | Mar 30, 2034 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG21K2201/065
- WIPO fieldOptics
- WIPO sectorInstruments
Abstract
An optical collector (15) for collecting extreme ultraviolet radiation or EUV light generated at a central EUV production site comprises a reflective shell (25). To cope with thermal loading of the collector and avoid deformations, the reflective shell (25) is mounted on a support structure (24), such that a cooling channel (29) is established between the back side of the reflective shell (25) and the support structure (24), the thickness of the reflective shell (25) is substantially reduced, such that the convective heat transfer between the back side of the reflective shell (25) and a cooling medium (26) flowing through the cooling channel (29) dominates the process of removing heat from the reflective shell (25) with respect to heat conduction, and a cooling circuit (33) is connected to the cooling channel (29); to supply a cooling medium (26) to the cooling channel (29) with a controlled coolant pressure and/or mass flow.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.