Hole mobility in germanium irradiated with large fluences of fast neutrons

Abstract

The Hall mobility of holes in germanium irradiated with large fluences of fast neutrons 10 14 cm À2 < F < 10 19 cm À2 is studied over a wide range of temperature 7 K < T < 300 K and for radiation defect concentrations of 1 Â 10 14 cm À3 < N RD < 3 Â 10 17 cm À3 . After irradiation the original samples became p-type, low-resistance samples. Electrical properties of neutron irradiated germanium are determined by acceptor-like radiation defects with energy levels of E V þ 0:016 eV. It is found that at temperatures above 100 K the hole mobility in neutron irradiated germanium and in germanium doped by gallium changes with temperature by general laws, and their values are comparable. The main scattering mechanisms inherent to homogeneous doped crystalline semiconductors are established also in neutron irradiated germanium. The results give rise to conclude that germanium irradiated with large fluences of fast neutrons can be assumed as crystalline with a homogeneous radiation defect distribution.

The characteristics of the Coulomb gap in the density of states of germanium doped irradiation defects

“…Germanium, irradiated with large fluences of fast neutrons, can also serve as a convenient object for experimental studies of hopping conductivity and nonmetal-metal transitions [1][2][3][4].…”