Degradation of mobility in neutron irradiated GaAs by the increased scattering from multiply charged ionized defects

Abstract

Mobility changes were measured at temperatures from 15 to 305 K in n-GaAs van der Pauw samples irradiated by fast reactor neutrons. The inverse mobility values, obtained from the variable temperature Hall measurements were fitted using the relation μ−1=AT−3/2+BT3/2. The inverse mobility was found to increase as a result of neutron irradiations over the whole range of temperature; the increase is attributed to the increased scattering from neutron induced charged defects. The values of A found by the least square fitting were used to estimate the increased scattering effect from neutron-induced ionized defects after each step of irradiation. It is concluded that in order to explain the experimental results presented here, the creation of multiply charged defects must be considered.