Abstract: The number of bilayers required in a neutron multilayer mirror depends directly on the different scattering cross sections of the materials selected for this purpose. So, conventional systems generally alternate two metallic systems: one with a high scattering cross section like Ni and one with a negative cross section like Ti. In this study, we show that more complicated systems such as TiN/Ti have improved potentials compared to conventional systems, due to the high scattering cross section of nitrogen. We present an experimental study of this new system using a pseudo-reactive rf-sputtering system and different in-situ and ex-situ characterization methods. Well- defined multi-layer structures are obtained with periodicities in the range 20 - 70 angstroms. Titanium and titanium nitride layers appear crystallized even for very low thickness. This induces a quite high interface roughness as observed by grazing x-ray reflection and transmission electron microscopy. Long range roughness appears limited and neutron reflectivity measured with cold neutrons ($lambda $EQ 3.96 angstroms) is promising even for short periods around 40 angstroms.!28
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