Electrodeposition of Thin Silicon Films for Neutron Transmutation Doping

Thin silicon films were electrodeposited on glassy carbon (GC) from the KF-KCl (2:1) – 75 mol% KI – 1.5 mol% K2SiF6 melt under potentiostatic condition at 973 K. The synthesized films were single-phase, continuous, dense, and free from unwanted impurities. Neutron transmutation doping (NTD) of the samples was performed in the IVV-2M research reactor (RR) at a thermal neutron flux density of 1.81013 cm−2s−1 for 7.7 h in order to form the 31P isotope dopant. The irradiated samples were studied by scanning electron microscopy with energy-dispersive X-ray spectroscopy, X-ray diffraction, mass spectrometry, and gamma-ray spectrometry. Some excess of the minimum significant specific activity of the irradiated samples was explained by the formation of the 182Ta isotope due to the presence of tantalum traces in the GC substrate. The formation of the 31P isotope by the NTD process was confirmed. The calculated values of 31P concentration and electrical resistivity were 4.91016 cm–3 and 0.15 cm, respectively.