Neutron Mirror Fabrication System

Neutron Mirror Fabrication Facility

(Ion Beam Deposition and Vacuum Evaporation for large neutron mirrors)
A Multilayer mirror is one of the most useful devices for slow neutron experiments. Multilayer mirrors and supermirrors are applied to neutron optical devices, such as neutron guide tube.

The multilayer mirror consists of alternating layers of two materials with different potential energies for the neutron. It has artificial lattice spacing (d-spacing) and gives one-dimensional optical potentials for a neutron beam. Supermirror is a stack of multilayers with gradually increasing value of the d-spacing. A multilayers with small d-spacing and supermirror with large-m is desirable to enlarge utilization efficiency for neutron scattering experiments. Recently we succeeded in fabricating large-m(m=5)NiC/Ti using ion beam sputtering technique. The Ion beam deposition system is used for high quality mirror fabrication. It has ion sources for sputtering and assist. The sample size is 20cm diameter and the number of target in this system is 5. The vacuum evaporation system is used for large size mirrors. Eight mirrors of 11×35cm² can be fabricated at once.

Ion Beam Deposition System (Veeco, IBD-350)
Ion Beam Deposition System (Veeco, IBD-350)