Development of EUV point diffraction interferometry using the NewSUBARU undulator radiation

摘要

An extreme ultra-violet phase-shifting point diffraction interferometer (PS/PDI) was studied by using the NewSUBARU undulator radiation. The beam line was equipped with a monochromator for PDI measurement. To improve the converging performance of the undulator radiation, a new beam line suitable for PDI was designed. From the examination of monochromaticity required for PDI, the 0th-order light of the monochromator was used in the experiment. The higher-order radiation of the undulator was eliminated by the reflection band of the Mo/Si multilayer mirrors. By means of improvements of the pre-alignment method and of the mask structure, a higher contrast than ever was achieved in the interference fringes.