At-wavelength, system-level flare characterization of extreme-ultraviolet optical systems.
The extreme-ultraviolet (EUV) phase-shifting point-diffraction interferometer (PS/PDI) has recently been developed to provide high-accuracy wave-front characterization critical to the development of EUV lithography systems. Here we describe an enhanced implementation of the PS/PDI that significantly extends its measurement bandwidth. The enhanced PS/PDI is capable of simultaneously characterizing both wave front and flare. PS/PDI-based flare characterization of two recently fabricated EUV 10x-reduction lithographic optical systems is presented.
Naulleau
P
P
Center for X-Ray Optics, Lawrence Berkeley National Laboratory, Berkeley, California 94720, USA. pnaulleau@lbl.gov
Goldberg
K A
KA
Gullikson
E M
EM
Bokor
J
J