Nikon Corporation

Toshihiro Sasaya

Kazuo Ushida

Yutaka Suenaga

Romeo I Mercado

Kazumasa Endo

A high-performance projection exposure apparatus and method which can adjust optical characteristics which are rotationally asymmetric with respect to the optical axis of projection optical system and which remain in the projection optical system. In exemplary embodiments, the projection exposure apparatus includes an illumination optical system, a projection optical system and a plurality of optical elements. The illumination optical system illuminates a first object, and the projection optical system projects an image of the first object onto a second object under a predetermined magnification. The optical elements are set between the first object and the second object, and has rotationally asymmetric powers with respect to an optical axis of the projection optical system. Consequently, the optical elements can correct an optical characteristic rotationally asymmetric with respect to the optical axis of the projection optical system remaining in the projection optical system.

Projection exposure apparatus and method with adjustment of rotationally asymmetric optical characteristics

A method of manufacturing an exposure apparatus includes a step of providing a projection optical system that projects a pattern image formed on a mask onto a photosensitive substrate. Additionally, a surface of a correction member having a predetermined thickness is locally tooled or processed in order to correct random aberration that remains in the projection optical system. The tooled correction member is arranged between the mask and the substrate, irrespective of the mask. Furthermore, when the projection optical system is provided, an aberration caused due to the predetermined thickness of the correction member is taken into account in advance.

Method of manufacturing and using correction member to correct aberration in projection exposure apparatus

In the projection optical system that projects an image of the first object onto the second object with a fixed reduction ratio and a projection aligner equipped therewith, said projection optical system comprises, viewed from said first object side, in order of succession, the first group of lenses with positive refractive power, and the second group of lenses virtually consists of afocal system, and the third group of lens with positive refractive power, and if the focal length of said projection optical system is represented by F, the projection magnification ratio of said projection optical system is represented by B, the distance between said first object and said second object is represented by L, the distance from said first object to the lens surface that is closest to said first group of lenses is represented by d.sub.0, the focal length of said first group of lenses is represented by f.sub.1, and the focal length of said third group of lenses is represented by f.sub.3 herein, then the following conditions should be satisfied:

Projection optical system and projection exposure apparatus

A projection optical system that projects an image of an object in an object surface onto an image surface with a fixed reduction magnification comprises, in light path order from the object surface: a first group of lenses with positive refractive power; a second group of lenses forming an approximately afocal system; and a third group of lenses with positive refractive power. The projection optical system has a focal length F, the projection optical system has a projection magnification B, the object surface and the image surface are separated by a distance L, and a lens surface in the first group of lenses that is closest to the object surface is separated from the object surface by a distance d.sub.0. A paraxial marginal ray from an axial object point on the object surface enters the second group of lenses G.sub.2 at an entrance height h.sub.1 from an optical axis, and the paraxial marginal ray from the axial object point on the object surface emerges from the second group of lenses G.sub.2 at an emergence height h.sub.2 from the optical axis. The optical system is characterized by the following:

In the projection optical system that projects an image of the first object onto the second object with a fixed reduction ratio and a projection aligner equipped therewith, said projection optical system comprises, viewed from said first object side, in order of succession, the first group of lenses with positive refractive power, and the second group of lenses virtually consists of afocal system, and the third group of lens with positive refractive power, and if the focal length of the overall system is represented by F, the projection magnification ratio of said projection optical system is represented by B, the distance between said first object and said second object is represented by L, and when a ray from the second object side of said projection optical system that is parallel to the optical axis of said projection optical system is incident on said projection optical system, a distance between a point where an extension on the first object side of said ray intercepts the optical axis and said first object plane is represented by e, and a height of said ray on said first object from the optical axis of said projection optical system, when said ray, coming through said projection optical system, reaches said first object is represented by h, then the following conditions should be satisfied:

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Yokohama, Japan

Toshihiro Sasaya