.ni / Ti Neutron Multilayer Film Periodic Structure

Neutron multilayer devices made of Ni/Ti multilayer are widely used into apparatus of neutron scattering experiment.In the systems of Ni/Ti periodical multilayer,both periodical structure and interfacial condition can influence the reflectivity of beam of incident neutron.So in this multilayer systems,the periodical structure and condition of interface can decide significantly the quality of this neutron multilayer devices(in this paper it denote the Ni/Ti multilayer).In this paper,we fabricated the sample in the devices of ultra vacuum magnetron sputtering which was designed of fabricated in the Institute of Physics,Chinese Academy of Sciences.In our experiment,we chose Nickel and Titanium to be material.At the different technology conditions,we fabricated a series of multilayer by the method of DC magnetron sputtering and particular mode of sweeping.Then we use the low angle X-ray Diffraction to detect periodical structure of multilayer in the Material Center Experiment of Tsinghua University.We calculated the periodic thickness and interfacial roughness of multilayer by means of fitting the XRD diffraction curves.The main idea of this paper is to study the variations of periodical thickness and interfacial roughness of the sample multilayer under different technology conditions and in the different sputtering position under the same technology conditions,and then further we can obtain a optimum sputtering condition.It is found that both of the evenness of periodical thickness and interfacial roughness of the multilayer fabricated by sweeping mode are better than the ones obtained by the stationary mode;moreover,under the sweeping mode,the interfacial roughness will decrease as the speed of substrate increasing.