Patent · US Expired

Projection objective for microlithography

US7271876B2 · kind B2 · utility

5Cited by

4References

6Claims

0Family size

Assignee

Carl Zeiss SMT GmbH · DE

Inventors

Wilhelm Ulrich · Aalen, DE
Gerhard Fuerter · Ellwangen, DE
Michael Gerhard · Aalen, DE

Key dates

Filing date	Aug 17, 2004
Grant date	Sep 18, 2007
Priority date	—
Expiry date	Sep 20, 2024

Classification

Technology area (CPC G)Physics
CPC primaryG03F7/70566
WIPO fieldOptics
WIPO sectorInstruments

Abstract

A projection objective for microlithography for imaging a pattern arranged in the object plane of the projection objective into the image plane of the projection objective has at least one polarization splitter device that is operated only once in transmission or reflection. By using this device, polarization-dependent differences in the intensity and response of the light passing through the objective, which lead to a worsening of the imaging quality of the projection objective, can largely be avoided.

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