Patent · US Active

Projection optical unit for microlithography and method for producing a structured component

US11650510B2 · kind B2 · utility

0Cited by

2References

20Claims

0Family size

Assignee

Carl Zeiss SMT GmbH · DE

Inventors

Hans-Juergen Rostalski · Oberkochen, DE
Holger Muenz · Aalen, DE
Christoph Menke · Oberkochen, DE

Key dates

Filing date	Dec 16, 2021
Grant date	May 16, 2023
Priority date	—
Expiry date	Dec 16, 2041

Classification

Technology area (CPC G)Physics
CPC primaryG03F7/7025
WIPO fieldOptics
WIPO sectorInstruments

Abstract

A projection optical unit for microlithography includes a plurality of mirrors and has a numerical aperture having a value larger than 0.5. The plurality of mirrors includes at least three grazing incidence mirrors, which deflect a chief ray of a central object field point with an angle of incidence of greater than 45°. Different polarized light beams passing the projection optical unit are rotated in their polarization direction by different angles of rotation. The projection optical unit includes first and second groups of mirrors. The second group of mirrors includes the final two mirrors of the plurality of mirrors at the image side. A linear portion in the pupil dependence of the total geometrical polarization rotation of the projection optical unit is less than 20% of a linear portion in the pupil dependence of the geometrical polarization rotation of the second group of mirrors.

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.