Illumination optics for microlithography

US8937708B2 · kind B2 · utility

Assignee

• Carl Zeiss SMT GmbH · DE

Inventors

• Martin Endres · Oberkochen, DE
• Ralf Stuetzle · Aalen, DE
• Jens Ossmann · Aalen, DE

Key dates

• Filing date: May 28, 2010
• Grant date: Jan 20, 2015
• Expiry date: May 2, 2033

Classification

• Technology area (CPC G): Physics
• CPC primary: G03F7/70191
• WIPO field: Optics
• WIPO sector: Instruments

Abstract

An illumination optics for microlithography includes an optical assembly for guiding illumination light to an object field to be illuminated in an object plane. The illumination optics can divide an illumination light radiation bundle into a plurality of radiation sub-bundles which are assigned to different illumination angles of the object field illumination. The illumination optics is configured so that at least some of the radiation sub-bundles are superimposed in a superposition plane which is spaced from the object plane and which is not imaged into the object plane in which superposition takes place. This superposition is such that edges of the superimposed radiation sub-bundles coincide at least partially. In some embodiments, a field intensity setting device includes a plurality of adjacent individual diaphragms which at least attenuate illumination light when exposed thereon. These individual diaphragms are insertable into an illumination light radiation bundle in a direction parallel to an object displacement direction. All individual diaphragms of the field intensity setting device are insertable into the illumination light radiation bundle from one and the same side.