Lithographic apparatus and device manufacturing method
US10495985B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Oct 9, 2018 |
| Grant date | Dec 3, 2019 |
| Priority date | — |
| Expiry date | Oct 9, 2038 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG03F9/7096
- WIPO fieldOptics
- WIPO sectorInstruments
Abstract
A lithographic apparatus including: a projection system to project radiation onto a substrate supported on a substrate stage, during an exposure phase; a sensing system to sense a property of the substrate on the stage during a sensing phase; and a positioning system to determine a position of the stage relative to a reference system via a radiation path between the stage and the reference system, wherein the apparatus is configured to control stage movement relative to the reference system in the sensing phase and to control other movement relative to the reference system during the exposure phase; the stage or reference system having an outlet to provide a gas curtain to reduce ingress of ambient gas into the path; and the apparatus is operative such that a characteristic of the gas curtain is different in at least part of the sensing phase compared to in the exposure phase.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.