Patent · US Active

Illumination system of a microlithographic projection exposure apparatus

US8773639B2 · kind B2 · utility

1Cited by

2References

21Claims

0Family size

Assignee

Carl Zeiss SMT GmbH · DE

Inventors

Markus Deguenther · Aalen, DE
Andras G. Major · Oberkochen, DE
Anne Christine Andresen · Westensee, DE

Key dates

Filing date	Dec 7, 2009
Grant date	Jul 8, 2014
Priority date	—
Expiry date	Jan 22, 2032

Classification

Technology area (CPC G)Physics
CPC primaryG03F7/702
WIPO fieldOptics
WIPO sectorInstruments

Abstract

An illumination system of a microlithographic projection exposure apparatus comprises a pupil surface and an arrangement of individually drivable beam deviating elements. Each beam deviating element is configured to direct light impinging thereon onto different positions on the pupil surface in response to a control signal applied to the beam deviating element. According to the disclosure an attenuation unit is provided which is configured to reduce the intensity of light, which is directed by any arbitrary beam deviating element (onto the pupil surface, by more than 50%. This makes it possible to reduce the intensity of light in the pupil surface that has been reflected by defective beam deviating elements.

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