Determination of shallow defect levels using thermally stimulated current in implant-layer/substrate junctions of GaAs MESFETs

Thermally stimulated current measurements have been made using test samples of np- junctions formed by ion-implantation on semi-insulating substrates. The results of measurements demonstrate that in spite of a high-value series resistance of the substrate these junctions can be used for rapid identification of shallow electron traps. The trap energy levels determined for the test samples are at 0.13eV and 0.29eV below the bottom of the conduction band possibly arising due to implantation damage or induced by thermal processes.