Retainer, exposure apparatus, and device fabrication method

Abstract

A retainer includes a plurality of support members for supporting an optical element, and a plurality of elastic members arranged between the plurality of support members, each elastic member applying an elastic force to the optical element in a direction perpendicular to a gravity direction.

Description

[0001] This application is a continuation of prior application Ser. No. 10 / 851,955, filed May 21, 2004, the contents of which are hereby incorporated by reference in their entirety.[0002] This application claims a benefit of foreign priority based on Japanese Patent Application No. 2003-144096, filed on May 21, 2003, which is hereby incorporated by reference herein in its entirety as if fully set forth herein. BACKGROUND OF THE INVENTION [0003] The present invention relates generally to precision machines for mounting an optical element, and more particularly to a projection optical system in an exposure apparatus, etc. The present invention is suitable, for example, for a retainer that holds an optical element for a more precise imaging relationship in an exposure apparatus in projecting and exposing an image on an original sheet, such as a mask or reticle (these terms are used interchangeably in this application) onto an object, such as a single crystal substrate for a semiconduct...

AI Technical Summary

Benefits of technology

The present invention provides a retainer, exposure apparatus, and device fabrication method that can improve optical performance by reducing aberration caused by deformation and positional offset of an optical element. The retainer includes support members and elastic members that apply elastic force to the optical element in a perpendicular direction. The exposure apparatus includes the retainer and an optical system for exposing a pattern on a mask or reticle onto an object. The device fabrication method involves exposing a pattern on a mask and developing the exposed object. Overall, the invention improves the accuracy and quality of optical performance in various applications.

Problems solved by technology

In particular, the projection lens tends to have a larger caliber and a larger lens capacity due to the recent high NA in the projection optical system, and easily deforms by its own weight.

In addition, diffraction optical elements, which have been eagerly studied recently, also tend to deform due to its thinness.

However, Japanese Patent Application, Publication No. 2001-284226 does not consider the flatness of the lens support points 1200 and lens deformation.

Thus, this reference has a difficulty in realizing a projection optical system with little aberration due to such a lens's deformation.

This causes the lens to incur a large load from the spring members of the flex mount parts 2200.

This causes the large birefringence and possibly breaks the lens, and has a difficulty in realization.

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