Patent · US Active

Microlithographic apparatus and method of varying a light irradiance distribution

US9720336B2 · kind B2 · utility

0Cited by

5References

14Claims

0Family size

Assignee

Carl Zeiss SMT GmbH · DE

Inventors

Holger Walter · Aalen, DE
Alexander Wolf · Oberkochen, DE

Key dates

Filing date	Sep 11, 2015
Grant date	Aug 1, 2017
Priority date	—
Expiry date	Sep 12, 2035

Classification

Technology area (CPC G)Physics
CPC primaryG03F7/70308
WIPO fieldOptics
WIPO sectorInstruments

Abstract

A microlithographic apparatus includes an objective that includes a transmission filter that is configured to variably modify a light irradiance distribution in a projection light path. The transmission filter includes a plurality of gas outlet apertures that are configured to emit gas flows that pass through a space through which projection light propagates during operation of the microlithographic apparatus. The transmission filter further includes a control unit which is configured to vary a number density of ozone molecules in the gas flows individually for each gas flow. In this manner it is possible to finally adjust the transmittance distribution of the transmission filter.

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