Technological Features of Irradiation of Sip+-n-n+ Diodes with Electrons at Elevated Temperatures

The behavior of the lifetime of nonequilibrium charge carriers τp, the reverse current IR, and the forward-voltage drop UF in electron-irradiated (Eirr = 6 MeV) commercial p+-n-n+ diodes at irradiation temperatures in the range of Tirr = 20–400°C is studied. Studies have been performed for samples fabricated on a single-crystal Si substrate either doped with phosphorus in the course of growth by the Czochralski method (Cz-n-Si:P) or doped with phosphorus by nuclear transmutations, neutron-transmutation doped Si (NTD n-Si:P). It is shown that, by choosing the temperature conditions of technological irradiation, one can solve the problem of attaining small values of τp at a minimal increase in UF and IR in fast-response diodes. It is established that, in the case of comparable variations in τp in the base region of diodes, the best relation between UF and IR is observed at Tirr = 300°C in n-Si:P samples doped by the Czochralski method and at Tirr = 350°C in samples doped by reactions induced by thermal neutrons.