ABSTRACTHigh temperature annealing of Si 3 N4 and SiO2 capped high purity LPE GaAs is shown to result in a reduction in the surface carrier concentration by about an order of magnitude. Au Schottky contacts made on the annealed samples were found to have severely degraded breakdown characteristics. Using deep level transient spectroscopy, deep levels at EC–.58eV, EC–.785eV were detected in the SiO2, capped samples and EC–.62eV, EC–.728eV in the Si3N4 capped Samples while none was detected in the unannealed samples.The electrical degradations are explained in terms of compensation mechanisns and depletion layer recombination-generation currents due to the deep levels.
High-temperature deep-level transient spectroscopy system for defect studies in wide-bandgap semiconductors