Accession Number : ADP007233

Title :   Development of Reflective Optical Systems for XUV Projection Lithography,

Corporate Author : LOS ALAMOS NATIONAL LAB NM

Personal Author(s) : Viswanathan, V. K. ; Newman, Brian E.

Report Date : 22 MAY 1992

Pagination or Media Count : 4

Abstract : We describe two full-field reflective reduction systems (1 cm2 and 6.25 cm2 image area) and one scanning system (25mm x scan length image size) that meet the performance requirements for 0.1 microns resolution projection lithography using extreme-ultraviolet (XUV) wavelengths from 10 to 15 nm. These systems consist of two centered, symmetric, annular aspheric mirrors with 35-40 % central obscuration, providing a reduction ratio of 3.3 x. Outstanding features include the remarkably low distortion over the entire image field and the comparatively liberal tolerances on the mirror radii and alignment. While optimized annular illumination can improve the performance, the required performance can be met with full illumination, thereby allowing simpler system design.

Descriptors :   *LITHOGRAPHY, REFLECTION, ILLUMINATION, FAR ULTRAVIOLET RADIATION.

Subject Categories : Photography

Distribution Statement : APPROVED FOR PUBLIC RELEASE