Reduced efficiency variation in perforated neutron detectors with sinusoidal trench design

The design of an idealized perforated (microstructured) planar diode neutron detector is presented that has little variation in efficiency as a function of the incident neutron's direction. The reduced angular variation is obtained by using sinusoidal-trench perforations rather than previous hole or straight-trench perforations. The resulting efficiency variation from changing the azimuthal angle of neutron incidence exhibits a variation of only 3% about the mean azimuthal efficiency. The efficiency variation resulting from changes in the polar angle of neutron incidence is limited to 10% of the normal-incidence efficiency over the polar range of 0–60°. 10B, 6LiF, and 6Li-metal filled perforations are considered.