Illumination system of a microlithographic projection exposure apparatus

US9310690B2 · kind B2 · utility

Assignee

• Carl Zeiss SMT GmbH · DE

Inventors

• Markus Deguenther · Aalen, DE
• Vladimir Davydenko · Bad Herrenalb, DE
• Thomas Korb · Schwäbisch Gmünd, DE
• Frank Schlesener · Oberkochen, DE
• Stefanie Hilt · Aalen, DE
• Wolfgang Hoegele · Rosenheim, DE

Key dates

• Filing date: Nov 17, 2014
• Grant date: Apr 12, 2016
• Expiry date: Nov 17, 2034

Classification

• Technology area (CPC G): Physics
• CPC primary: G03F7/70425
• WIPO field: Optics
• WIPO sector: Instruments

Abstract

An illumination system includes an optical integrator having a plurality of light entrance facets, whose images at least substantially superimpose in a mask plane. A spatial light modulator transmits or reflects impinging projection light in a spatially resolved manner. A pupil forming unit directs projection light onto the spatial light modulator. An objective images a light exit surface of the spatial light modulator onto the light entrance facets of the optical integrator so that an image of an object area on the light exit surface completely coincides with one of the light entrance facets. A control unit controls the spatial light modulator such that along a scan direction a length of an image, which is formed on a mask from a light pattern in the object area, gradually increases at a beginning of a scan cycle and gradually decreases at the end of the scan cycle.