Two-beam interference apparatus and two-beam interference exposure system
US9507248B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Nov 20, 2012 |
| Grant date | Nov 29, 2016 |
| Priority date | — |
| Expiry date | Jun 1, 2035 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG03F7/70408
- WIPO fieldOptics
- WIPO sectorInstruments
Abstract
A two-beam interference apparatus may include a wafer stage on which a wafer may be set, a beam splitter to split first laser light into second and third laser light having a beam intensity distribution elongated in a first direction within a surface of the wafer, and an optical system to guide the second and third laser light onto the wafer. The wafer is irradiated with the second laser light from a second direction perpendicular to the first direction, and the third laser light from a third direction perpendicular to the first direction but different from the second direction, to thereby cause interference of the second and third laser light on the wafer. This apparatus increases the accuracy of the two-beam interference exposure.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.