The modification of single crystal epitaxial ZnO thin films grown by Pulsed Laser Deposition on c-axis oriented sapphire substrates by Ion Beam Processing was investigated. Nitrogen doping of the films was attempted using nuclear transmutation using the <sup>16</sup>O (<sup>3</sup>He, <sup>4</sup>He) <sup>15</sup>O reaction at 6.6 MeV. The <sup>15</sup>O product is unstable and decays to <sup>15</sup>N after several minutes by positron emission. There are several potential advantages to using nuclear transmutation including producing nitrogen atoms on the correct lattice site for doping and reduced crystal damage as compared to conventional ion beam implantation. In the experiments in this thesis the doping levels achieved ~10<sup>14</sup> cm<sup>-3</sup> were too low to be expected to dope the films to p-type. However several beneficial effects due to the ion beam processing were observed, including large increases in resistivity, reduction of defect luminescence, and substantial increases in the response of photoconductive detectors. In addition to desired effects in some films it was also found that in some films bubble like structures approximately 10 ìm in diameter were formed where the thin film delaminated from the surface. It was assumed that mechanism for the bubble formation was the build up of helium gas at the sapphire/ZnO interface.
| Identifer | oai:union.ndltd.org:NCSU/oai:NCSU:etd-01042006-015801 |
| Date | 05 January 2006 |
| Creators | Wellenius, Patrick |
| Contributors | John Muth, Robert Kolbas, Salah Bedair |
| Publisher | NCSU |
| Source Sets | North Carolina State University |
| Language | English |
| Detected Language | English |
| Type | text |
| Format | application/pdf |
| Source | http://www.lib.ncsu.edu/theses/available/etd-01042006-015801/ |
| Rights | unrestricted, I hereby certify that, if appropriate, I have obtained and attached hereto a written permission statement from the owner(s) of each third party copyrighted matter to be included in my thesis, dissertation, or project report, allowing distribution as specified below. I certify that the version I submitted is the same as that approved by my advisory committee. I hereby grant to NC State University or its agents the non-exclusive license to archive and make accessible, under the conditions specified below, my thesis, dissertation, or project report in whole or in part in all forms of media, now or hereafter known. I retain all other ownership rights to the copyright of the thesis, dissertation or project report. I also retain the right to use in future works (such as articles or books) all or part of this thesis, dissertation, or project report. |
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