Báo cáo sinh học: Influence of helium-ion bombardment on the optical properties of ZnO nanorods/p-GaN light emitting diodes

ITuyển tập báo cáo các nghiên cứu khoa học quốc tế ngành hóa học dành cho các bạn yêu hóa học tham khảo đề tài: nfluence of helium-ion bombardment on the optical properties of ZnO nanorods/p-GaN light emitting diodes
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Báo cáo sinh học: " Influence of helium-ion bombardment on the optical properties of ZnO nanorods/p-GaN light emitting diodes"Nanoscale Research Letters This Provisional PDF corresponds to the article as it appeared upon acceptance. Fully formatted PDF and full text (HTML) versions will be made available soon. Influence of helium-ion bombardment on the optical properties of ZnO nanorods/p-GaN light emitting diodes Nanoscale Research Letters 2011, 6:628 doi:10.1186/1556-276X-6-628 N H Alvi (nhalvi@gmail.com) S Hussain (shussainawan@gmail.com) J Jensen (jejen@ifm.liu.se) O Nur (Omer.Nour@itn.liu.se) M Willander (magwi@itn.liu.se) ISSN 1556-276X Article type Nano Express Submission date 17 June 2011 Acceptance date 12 December 2011 Publication date 12 December 2011 Article URL http://www.nanoscalereslett.com/content/6/1/628 This peer-reviewed article was published immediately upon acceptance. It can be downloaded, printed and distributed freely for any purposes (see copyright notice below). Articles in Nanoscale Research Letters are listed in PubMed and archived at PubMed Central. For information about publishing your research in Nanoscale Research Letters go to http://www.nanoscalereslett.com/authors/instructions/ For information about other SpringerOpen publications go to http://www.springeropen.com © 2011 Alvi et al. ; licensee Springer.This is an open access article distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/2.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.Influence of helium-ion bombardment on the optical properties ofZnO nanorods/p-GaN light-emitting diodesN. H. Alvi*1, S. Hussain1, J. Jensen2, O. Nur1, and M. Willander11 Department of Science and Technology (ITN), Campus Norrköping, Linköping University, 60174Norrköping, Sweden2 Department of Physics, Chemistry and Biology, Linköping University, 58183, Linköping, Sweden*Corresponding author: nhalvi@gmail.comEmail addresses:NHA: nhalvi@gmail.comSH: shussainawan@gmail.comJJ: jejen@ifm.liu.seON: omeno@itn.liu.seMW: magwi@itn.liu.seAbstractLight-emitting diodes (LEDs) based on zinc oxide (ZnO) nanorods grown by vapor-liquid-solidcatalytic growth method were irradiated with 2-MeV helium (He+) ions. The fabricated LEDs wereirradiated with fluencies of approximately 2 × 1013 ions/cm2 and approximately 4 × 1013 ions/cm2.Scanning electron microscopy images showed that the morphology of the irradiated samples is notchanged. The as-grown and He+-irradiated LEDs showed rectifying behavior with the same I-Vcharacteristics. Photoluminescence (PL) measurements showed that there is a blue shift ofapproximately 0.0347 and 0.082 eV in the near-band emission (free exciton) and green emission of theirradiated ZnO nanorods, respectively. It was also observed that the PL intensity of the near-bandemission was decreased after irradiation of the samples. The electroluminescence (EL) measurementsof the fabricated LEDs showed that there is a blue shift of 0.125 eV in the broad green emission afterirradiation and the EL intensity of violet emission approximately centered at 398 nm nearlydisappeared after irradiations. The color-rendering properties show a small decrease in the color-rendering indices of 3% after 2 MeV He+ ions irradiation. 1IntroductionZinc oxide (ZnO) with bad gap of 3.37 eV has very attractive properties to play a major role innanoscale electronic and optoelectronic devices. Its excellent properties combined with the easiness ofgrowing it in the nanostructure form have made it one of the most attractive and versatilesemiconductor [1–2]. It has both semiconducting and piezoelectric properties and in addition it isbiocompatible and bio-safe. ZnO possesses deep level emission (DLE) bands emitting all the colors inthe visible region and has good color-rendering properties [3–5].Among all of the known oxide semiconductors, ZnO nanorods (NRs) are the best choice for ...