1. Field of the Invention
The present invention relates to an optical element supporting device for precisely adjusting the position of an optical element such as a lens or mirror, an exposure apparatus using the same, and a device manufacturing method.
2. Description of the Related Art
A semiconductor exposure apparatus is an apparatus for transferring a circuit pattern of an original (reticle) onto a substrate (silicon wafer). When a circuit pattern is transferred, a projection optical system that serves as an optical device is used in order to focus a reticle pattern on a wafer. To prepare a highly integrated circuit, high-resolution performance is required for the projection optical system.
In order to enhance the resolution performance of the projection optical system, it is necessary to increase the numerical aperture (NA) of the optical system as well as to reduce the optical aberration severely. However, when a lens constituting the optical system is eccentric with respect to an optical axis, astigmatism, coma aberration, or eccentric distortion occurs. Accordingly, in recent years, an apparatus for adjusting the position of a lens has been proposed in order to correct these aberrations.
For example, the adjustment mechanism disclosed in Japanese Patent Laid-Open No. 2004-347821 adjusts the position of an optical member by holding a support member that supports an optical element with an elastic member and applying a force to the elastic member through a force supplying unit.
However, in the conventional adjustment mechanism as disclosed in Japanese Patent Laid-Open No. 2004-347821, a mechanism for adjusting the position of an optical member is large, which may lead to increase the size of a lens barrel constituting the projection optical system. Furthermore, the production cost may increase because of the complex shape of the elastic member.