8-12 July 2013
Effect of the alpha particle charge state and energy on irradiation induced deep level defects in ZnO
Presented by Dr. Wilbert MTANGI on 9 Jul 2013 from 17:40 to 18:40
Type: Poster Presentation
Track: Track A - Division for Condensed Matter Physics and Materials
A systematic investigation of the effects of varying alpha-particle energy and ionization state has been performed on alpha-particle irradiated Pd/ZnO Schottky contacts. Deep level transient spectroscopy performed on these contacts reveals three prominent deep level defects, E1, E2, and E3, in the as-deposited samples. For contacts irradiated with 600 keV He+ ions, the three prominent levels have been observed and two new levels have been induced, T2 and Eα1, with activation enthalpies of 0.30 eV and 0.46 eV, respectively. Eα1 with an activation enthalpy of 0.47 eV together with the three prominent levels E1, E2 and E3 have also been observed in contacts irradiated with 1.2 MeV He+. For contacts irradiated with 1.2 MeV He2+, the three prominent levels have also been observed and two new defects Eα1 and Eα2 with activation enthalpies of 0.46 eV and 0.77eV, respectively as determined from standard Arrhenius analysis, have been induced. Preliminary results indicate that particle energy has a strong impact on the formation of the Eα1 level and the formation of T2. Introduction of Eα2 has a strong dependence on the alpha-particle ionization state.