Nanometer interface and materials control for multilayer EUV-optical applications

► Multilayer optimization to the highest achieved reflectance: 70.3% record value. ► Growth control of thin layers down to 0.1 nm rms roughness. ► Diffusion barriers to enhance reflectance and improve thermal stability. ► Capping layers to protect against surface oxidation by photon exposure and cleaning. ► Multilayer optics for real lithographic systems: 69.6% on real optics.