B4C/Mo/Si high reflectivity multilayer mirror at 30.4 nm

The B4C/Mo/Si high reflectivity multilayer mirror was designed for He-II radiation (30.4 nm) using the layer-by-layer method. The theoretical peak reflectivity was up to 38.2% at the incident angle of 5 degrees. The B4C/Mo/Si multilayer was fabricated by direct current magnetron sputtering and measured at the National Synchrotron Radiation Laboratory (NSRL) of China. The experimental reflectivity of the B4C/Mo/Si multilayer at 30.4 nm was about 32.5%. The promising performances of the B4C/Mo/Si multilayer mirror could be used for the construction of solar physics instrumentation.