New evidence of dominant processing effects in standard and oxygenated silicon diodes after neutron irradiation

Abstract

Silicon diodes processed on standard and oxygenated silicon substrates by three different manufacturers have been irradiated by neutrons in a nuclear reactor. The leakage current density ( J D) increase is linear with the neutron fluence. J D and its annealing curve at 80°C do not present any sizeable dependence on substrate oxygenation and/or manufacturing process. The acceptor introduction rate ( β) of the effective substrate doping concentration ( N eff) is independent from the oxygen concentration when standard and oxygenated devices from the same manufacturer are considered. On the contrary, β significantly varies from one manufacturer to another showing that the β dependence on the particular process can be important, overtaking the small substrate oxygenation effect. Finally, the average saturation value of the N eff reverse annealing is slightly lower for the oxygenated samples, pointing out a positive effect of the substrate oxygenation even for devices irradiated by neutrons.