Fabrication of high uniformity Mo/Si multilayer with 120 mm diameter using magnetron sputtering

In order to prepare large size multilayer mirrors for extreme ultraviolet, soft X-ray and X-ray applications, the Mo/Si multilayer was deposited on flat substrate in diameter of 120 mm with the substrate scanning over rectangular targets. By adjusting the speed of substrate scanning over sputtering targets, the depositing rate can be controlled, and the uniformity of layer thickness is improved significantly. After deposition, period thicknesses of multilayer on different positions of the mirror were measured by an X-ray diffractometer. The measured results show that, within the diameter of 120 mm, the uniformity of period thickness is within 0.26%. The reflectivities on different positions of the multilayer mirror were measured at the National Synchrotron Radiation Laboratory. The results