Electric conductivity and ESR of amorphous silicon after ion implantation

Temperature dependence of conductivity in amorphous silicon after neon ion implantation at 3x1015 - 2x1017 cm-2 doses have been studied using direct current and EPR. It is established, that at T < 130 K the conductivity is realized through electrons localized near the Fermi level. In the temperature range from 130 to 250 K dominated is the contribution into the conductivity related to carriers excited into localized states in a valent zone tail. The conductivity according to nonlocalized states is observed at higher temperatures. Electrons participating in the conductivity are shown to be also responsible for EPR. Given is a model of localized state density in a mobility slit for amorphous silicon produced by ion implantation on the base of which experimental results are explained