Projection exposure system for microlithography and method for generating microlithographic images
AssigneeCarl-Zeiss-Stiftung
InventorsKarl-Heinz Schuster, Christian Wagner, Martin Schriever
Life of this patent
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Abstract
A method and an arrangement for microlithographic projection exposure at high aperture achieve a contrast increase by the polarization of the light perpendicular to the plane of incidence on the resist. Arrangements are provided which influence the tangential polarization or the linear polarization adapted to the dipole illumination in the illuminating system and in the reduction objective.
Claims18
A projection exposure system for microlithography comprising:
- a light source for supplying light along an optical axis;
- an illumination arrangement defining an illumination aperture and being disposed on said optical axis downstream of said light source;
- said illumination arrangement including:
- a first component for influencing the polarization of said light by generating more than 60% of tangential polarization of said light;
- and, a second component for determining said illumination aperture;
- a mask positioning device on said optical axis downstream of said illumination arrangement;
- a projection objective defining an image plane and being arranged on said optical axis downstream of said illumination arrangement;
- and,
- an object positioning device disposed on said optical axis downstream of said projection objective.
A projection exposure system for microlithography comprising:
- a light source for supplying light along an optical axis;
- an illumination arrangement defining an illumination aperture and being disposed on said optical axis downstream of said light source;
- said illumination arrangement including:
- a first component for influencing the polarization of said light by generating linearly polarized light;
- and, a second component for determining said illumination aperture as two light spots of dipole illumination with the direction of polarization being perpendicular to a connecting line drawn between the two light spots;
- a mask positioning device on said optical axis downstream of said illumination arrangement;
- a projection objective defining an image plane and being arranged on said optical axis downstream of said illumination arrangement;
- and,
- an object positioning device disposed on said optical axis downstream of said projection objective.
A projection exposure system for microlithography comprising:
- a light source for supplying light along an optical axis at a wavelength in the range of 100 nm to 200;
- an illumination arrangement disposed on said optical axis downstream of said light source and having a device for generating different geometries of the pupil illumination;
- a mask positioning device on said optical axis downstream of said illumination arrangement;
- a catadioptric reduction objective disposed on said optical axis downstream of said mask positioning device and projecting an image of said mask into an image plane;
- said objective having a last mirror at the end of said objective facing toward said image plane and forming beams to generate an image in said image plane;
- a device for influencing the polarization of said light and being disposed downstream of said last mirror;
- an object positioning unit disposed on said optical axis downstream of said device and an object defining a plane of incidence held in said object positioning unit;
- and,
- said device being matched to the adjusted geometry of said pupil illumination and being adjustable so that said beams are polarized essentially perpendicular to said plane of incidence.
A method for microlithographically generating an image with polarized light comprising the step of providing light beams which incident in an image plane and causing said light beams to interfere to form an image in said image plane;
- and, imparting a polarization to said light beams to have a preferred direction of said polarization orientated perpendicular to the incidence plane.
A method of using a projection exposure system for microlithography to generate microlithographic images with polarized light, the microlithographic exposure system including:
- a light source for supplying light along an optical axis;
- an illumination arrangement defining an illumination aperture and being disposed on said optical axis downstream of said light source;
- said illumination arrangement including:
- a first component for influencing the polarization of said light by generating more than 60% of tangential polarization of said light;
- and, a second component for determining said illumination aperture;
- a mask positioning device on said optical axis downstream of said illumination arrangement;
- a projection objective defining an image plane and being arranged on said optical axis downstream of said illumination arrangement;
- and, an object positioning device disposed on said optical axis downstream of said projection objective, the method comprising the steps of:
- forming light beams with said system and causing said light beams to incident in said image plane;
- causing said light beams to interfere to form an image in said image plane;
- and,
- imparting a polarization to said light beams to have a preferred direction of said polarization orientated perpendicular to the incidence plane.
Dependencies are inferred from the claim text.