The primary defects which were introduced into semi-insulating material by 1MeV electron irradiation were studied quantitatively by using normalized thermally stimulated current spectroscopy. Defects were produced which were essentially identical to those that had previously been denoted as T6*(0.13eV), T5(0.34eV) and T4(0.31eV). The respective production rates were 0.70, 0.08 and 0.23/cm. It was noted that T5 was also a strong trap in non-irradiated semi-insulating material. The T6* and T4 defects corresponded closely to the irradiation-induced traps, E2(0.14eV) and E3(0.30eV), which had already been extensively studied by means of deep-level transient spectroscopy and Hall-effect measurements and had been attributed to the As vacancy. It was therefore concluded that the T6* and T4 traps (and probably T5 as well) had a As-vacancy nature in semi-insulating GaAs.

D.C.Look, Z.Q.Fang, J.W.Hemsky, P.Kengkan: Physical Review B, 1997, 55[4], 2214-8