Euv lithography system for dense line patterning
US11099483B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | May 18, 2017 |
| Grant date | Aug 24, 2021 |
| Priority date | — |
| Expiry date | May 18, 2037 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG03F7/70325
- WIPO fieldOptics
- WIPO sectorInstruments
Abstract
Extreme ultra-violet (EUV) lithography ruling engine specifically configured to print one-dimensional lines on a target workpiece includes source of EUV radiation; a pattern-source defining 1D pattern; an illumination unit (IU) configured to irradiate the pattern-source; and projection optics (PO) configured to optically image, with a reduction factor N>1, the 1D pattern on image surface that is optically-conjugate to the 1D pattern. Irradiation of the pattern-source can be on-axis or off-axis. While 1D pattern has first spatial frequency, its optical image has second spatial frequency that is at least twice the first spatial frequency. The pattern-source can be flat or curved. The IU may include a relay reflector. A PO's reflector may include multiple spatially-distinct reflecting elements aggregately forming such reflector. The engine is configured to not allow formation of optical image of any 2D pattern that has spatial resolution substantially equal to a pitch of the 1D pattern of the pattern-source.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.