Patent DE-102004063848-A1 (DE)
Title: Lighting for microlithography projection exposure system, includes two dimensional light distribution device with two raster devices for receiving light from primary and secondary sources
Inventor: WANGLER JOHANNES
IPC: G03F7/20
Filed: 2004-12-30
Abstract: The lighting (10) comprises an optical axis (12), a light distribution device (30) for receiving light from a primary light source (11) and generating a pre-determined variable two-dimensional light intensity distribution on a first surface in the lighting system, a first raster device (35) with a first set of raster components (36) for receiving the light intensity distribution and generating a secondary light source and a second raster device (40) with a second set of raster components (41) for receiving light from the secondary light source and at least partially overlaying this light in the illumination field (51). The first raster components are arranged in a Cartesian two-dimensional field and the second raster components are arranged in a two-dimensional field which is rotation symmetrical relative to the optical axis. A fixed arrangement of optical devices for recombining beams of light with a low degree of light loss is located between the first and second raster components. The light distribution device comprises a mirror arrangement with a number of individual mirrors of which at least some can be pivoted about one or more axes relative to the others. The first raster components comprise rectangular lenses or lens devices with a prismatic refraction capability for generating a first refraction angle and the angle size and/or vector differs between at least two of these components. The second raster components are arranged in concentric round rings. Independent claims are also included for the following: (A) Method for preparing semiconductors or other fine structure components by illuminating a mask located in the object plane of a projection lens with light from the primary light source in this system and generating an image of the mask on a photosensitive substrate, in which the mask illumination step involves a variable adjustment of the two-dimensional intensity distribution in the first surface of the lighting system; (B) Second lighting system; and (C) Third lighting system. The second lighting system comprises a light distribution device for receiving light from a primary light source and generating a two-dimensional light intensity distribution in a pupil-forming surface in the lighting system, a zoomable honeycomb condenser for receiving light from the pupil-forming surface and generating an output light distribution with an adjustable aperture and a zoom system for converting an input light distribution in a variable size front focal surface of the zoom system into a rear focal surface in the zoom system. The third lighting system comprises a light distribution device for receiving light from a primary light source and generating a two-dimensional light intensity distribution in a pupil-forming surface in the lighting system and a zoomable honeycomb condenser for receiving light from the pupil-forming surface and generating an output light distribution with an adjustable aperture. The light distribution device comprises a honeycomb condenser with a first raster device having a first set of raster components arranged in a Cartesian two- dimensional field and a second raster device having a second raster components are arranged in a two-dimensional field which is rotation symmetrical relative to the optical axis. A fixed arrangement of optical devices for recombining beams of light with a low degree of light loss is located between the first and second raster components.