Characterization of deep levels using unconventional zero-bias thermally stimulated current in ion-implanted semi-insulating GaAs substrates

It has been observed that by forward biasing ion-implanted n⁺/SI GaAs substrate junctions, electrons can be injected and trapped at deep levels in the substrate at low temperatures, and that when thermally stimulated they give rise to a pure emission current under a zero-bias condition. Characteristics of these emission peaks Provide information concerning trap energy levels and emission sections. Results obtained using test structures on undoped and lightly Cr-doped LEC-grown materials are reported.