Metal-oxide-silicon diodes on deuterium-implanted silicon substrate

Ion implantation was used to incorporate deuterium at the Si-SiO₂ interface. Polycrystalline silicon gate metal-oxide-semiconductor diodes with 4 nm oxide grown on deuterium-implanted p-type (100) silicon substrate were investigated. It was observed that deuterium implantation at a light dose of 1 × 10¹⁴/cm² at 25 keV reduced oxide leakage current due to reduction in oxide charge and interface traps. Low-energy implant indicates possible deuterium loss during oxidation whereas in case of higher energy implant, the observed degradation was caused by enhanced substrate damage. Interface state density D_it as obtained from the conductance measurements suggests that implanted deuterium passivates the interface traps.