Patent Number: 6,295,164

Title: Multi-layered mirror

Abstract: A multi-layered mirror has a substrate, a first layer of a first substance, a second layer of a second substance. The refractive index of the first substance in a utilized wavelength region is different from that of the second substance. The first and second layers are laminated alternately on the substrate. To obtain a high reflectivity and superior optical characteristics, a multi-layered structure is formed within either the first layer or the second layer using at least two substances whose real parts of the complex indices of refraction in the utilized wavelength region are approximately the same. Alternatively, a layer surface is smoothed before forming a next layer thereon. An exposure apparatus that uses multi-layered mirrors of the present invention uses light with higher efficiency.

Inventors: Murakami; Katsuhiko (Kawasaki, JP), Shiraishi; Masayuki (Higashikurume, JP)

Assignee: Nikon Corporation

International Classification: G03F 7/20 (20060101); G21K 1/06 (20060101); G21K 1/00 (20060101); G02B 001/10 (); G02B 005/28 (); G21K 001/06 ()

Expiration Date: 09/25/2018