Evaluation of diffraction efficiency of 7600 lines/mm multilayer gratings fabricated with near field optics lithography in 1keV region

Koike, Masato; Kawazoe, Tadashi*; Imazono, Takashi; Miyauchi, Shinji*; Sano, Kazuo*; Otsu, Motoichi*

Multilayer gratings having a groove density of 7600 lines/mm have been fabricated by depositing Mo/SiO multilayer coating on the surface of laminar-type master gratings fabricated by use of a new lithography machine based on optical near field technologies. The diffraction efficiency was measured by reflectometers in the wavelength range of 0.7-2.0 nm at a synchrotron radiation facility. The multilayer grating having a groove depth of 3nm and multilayer period length of 5.33 nm showed diffraction efficiencies of 0.028 at 0.70 nm and 0.005 at 2.0 nm were observed for the incidence angles of 88.020 deg and 80.764 deg, respectively. We also discuss the analysis of the roughness in terms of Debye-Waller factor comparing the experimental and theoretical diffraction efficiencies as well as the groove depth using experimental efficiency minima of the zero-th order light.