  We report on the development of a 10B conversion layer optimized for
ultra-cold neutron detection with silicon detectors. The efficiency of this
layer is high and roughly uniform over a large ultra-cold neutron velocity
range. The designed titanium-boron-nickel multilayer film was deposited on
silicon using a microwave plasma-assisted co-sputtering method (first, for test
purpose, on silicon wafers, then directly on the surface of a CCD sensor). The
obtained sensor was then tested using both cold and ultra-cold neutrons.
