Localized states in different samples of beta-rhombohedral boron

The activation energy and relative concentration of localized states in beta-rhombohedral Boron obtained from several sources were studied by transient photoconductivity, space-charge-limited currents, thermally stimulated currents, and thermally stimulated depolarization currents. Activation energies for electron traps are 0.25 and 0.44 eV, and for hole traps, the activation energies are 0.23 and 0.36 eV. The differing location and density of localized states suggests that they are extrinsic in nature.