Preparation and accurate quantification of uranium coatings on thin backings for high-flux neutron detectors

Dense and uniform uranium coatings are fabricated on 2 μm-thick aluminized mylar foil via electrodeposition for high-flux neutron detection. The thin mylar backing is selected for its ductility and low neutron-interaction cross-section to minimize beam-related background signals. The coatings are quantified using two complementary alpha-spectrometry techniques: a small solid angle device (SSA) and a grid ionization chamber (GIC). The SSA provides superior energy resolution, while the GIC offers a significantly higher detection efficiency (approximately 200 times greater) for rapid measurement. The derived ²³⁸U masses are 322 μg and 300 μg, with relative uncertainties between 1.02% and 1.10%. Results from both techniques agree within uncertainties, confirmed by normalized standard deviations E_n < 0.01. This integrated approach-encompassing target fabrication, dual-method quantification, and GEANT4 simulation-ensures the reliability of fission coatings for subsequent high-precision neutron measurements.