DEFECT ANNEALING OF ALPHA-PARTICLE IRRADIATED N-GAAS

The annealing behaviour of irradiation induced defects in n-type GaAs irradiated at 300 K with 5.4 MeV alpha-particles from an americium-241 (Am-241) radio nuclide have been investigated. The annealing kinetics are presented for the alpha-particle induced defects Ealpha1-Ealpha5 detected in Organo-Metallic Vapor Phase Epitaxially (OMVPE) grown n-Ga As doped with silicon to 1.2 x 10(16) cm-3, these kinetics are compare d to those obtained for similar defects (E1-E5) detected after electro n irradiation. While defects Palpha1 and Palpha2 were detected after r emoval of the electron defects Ealpha4 and Ealpha5, respectively, a ne w defect labelled Palpha0, located 0.152 eV below the conduction band, was introduced by annealing. The thermal behaviour and trap character istics of these three defects (Palpha0-Palpha2) are presented. In an a ttempt to further characterise defects Palpha0 and Palpha1 a prelimina ry study investigating the emission rate field dependence of these def ects was conducted, it was observed that defect Palpha0 exhibited a fa irly strong field dependence while Palpha1 exhibited a much weaker dep endence.