Influence of helium-ion bombardment on the optical properties of ZnO nanorods/p-GaN light emitting diodes
2011 (English)In: Nanoscale Research Letters, ISSN 1931-7573, Vol. 6, no 628Article in journal (Refereed) Published
Light emitting diodes (LEDs) based on zinc oxide (ZnO) nanorods grown by vapor-liquid-solid (VLS) catalytic growth method were irradiated with 2 MeV helium (He+) ions. The fabricated LEDs were irradiated with fluencies of ~ 2×1013 ions/cm2 and ~ 4×1013 ions/cm2. Scanning electron microscopy (SEM) images showed that the morphology of the irradiated samples is not changed. The as-grown and He+ irradiated LEDs showed rectifying behaviour with the same I-V characteristics. Photoluminescence (PL) measurements showed that there is a blue shift of approximately 0.0347 eV and 0.082 eV in the near band emission (free exciton) and green emission of the irradiated ZnO nanorods, respectively. It was also observed that the PL intensity of the near band emission was decreased after irradiation of the samples. The electroluminescence (EL) measurements of the fabricated LEDs showed that there is a blue shift of 0.125 eV in the broad green emission after irradiation and the EL intensity of violet emission approximately centred at 398 nm was nearly disappeared after irradiations. The color rendering properties shows a small decrease in the color rendering indices of 3% after 2 MeV He+ ions irradiation.
Place, publisher, year, edition, pages
SpringerOpen , 2011. Vol. 6, no 628
IdentifiersURN: urn:nbn:se:liu:diva-69154DOI: 10.1186/1556-276X-6-628ISI: 000300300100001OAI: oai:DiVA.org:liu-69154DiVA: diva2:424205