TY  - JOUR
AU  - Sertsu, M. G.
AU  - Giglia, A.
AU  - Brose, S.
AU  - Park, D.
AU  - Wang, Z. S.
AU  - Mayer, Joachim
AU  - Juschkin, Larissa
AU  - Nicolosi, P.
TI  - Deposition and characterization of B$_{4}$C/CeO$_{2}$ multilayers at 6.x nm extreme ultraviolet wavelengths
JO  - Journal of applied physics
VL  - 119
IS  - 9
SN  - 1089-7550
CY  - Melville, NY
PB  - American Inst. of Physics
M1  - FZJ-2016-02788
SP  - 095301 -
PY  - 2016
AB  - New multilayers of boron carbide/cerium dioxide (B4C/CeO2) combination on silicon (Si) substrate are manufactured to represent reflective-optics candidates for future lithography at 6.x nm wavelength. This is one of only a few attempts to make multilayers of this kind. Combination of several innovative experiments enables detailed study of optical properties, structural properties, and interface profiles of the multilayers in order to open up a room for further optimization of the manufacturing process. The interface profile is visualized by high-angle annular dark-field imaging which provides highly sensitive contrast to atomic number. Synchrotron based at-wavelength extreme ultraviolet(EUV) reflectance measurements near the boron (B) absorption edge allow derivation of optical parameters with high sensitivity to local atom interactions. X-ray reflectivity measurements at Cu-Kalpha(8 keV) determine the period of multilayers with high in-depth resolution. By combining these measurements and choosing robust nonlinear curve fitting algorithms, accuracy of the results has been significantly improved. It also enables a comprehensive characterization of multilayers.Interface diffusion is determined to be a major cause for the low reflectivity performance. Optical constants of B4C and CeO2 layers are derived in EUV wavelengths. Besides, optical properties and asymmetric thicknesses of inter-diffusion layers (interlayers) in EUV wavelengths near the boron edge are determined. Finally, ideal reflectivity of the B4C/CeO2 combination is calculated by using optical constants derived from the proposed measurements in order to evaluate the potentiality of the design.
LB  - PUB:(DE-HGF)16
UR  - <Go to ISI:>//WOS:000372351900055
DO  - DOI:10.1063/1.4942656
UR  - https://juser.fz-juelich.de/record/809862
ER  -