Analysis of the electronic structures of nitrogen-doped, amorphous carbon samples and of nanodiamond films are carried out in order to determine their sp2 bonding concentration. The amorphous carbon samples under consideration are deposited onto polytetrafluoroethylene (PTFE) polymer substrates by hot wire plasma sputtering of graphite in varying nitrogen concentration atmospheres. The deposition or modification of the substrates surface may lend itself to increasing hardness and wear resistance. Eventually these polymer substrates may be used for applications in the field of biomaterials, focusing on cardiovascular surgery, where a low blood/surface interaction is important.
The primary technique used in this study is x-ray absorption spectroscopy, measured at the Advanced Light Source synchrotron at the Lawrence Berkeley National Laboratory, Berkeley, USA. A method of analyzing these spectra was then developed to determine the sp2 bonding concentrations in carbon films.
Through this newly developed analysis method, the sp2 bonding concentrations in these samples increases from 74 to 93% with growing nitrogen doping. The diamond films presented here are deposited on silicon wafer substrates in a methane atmosphere by microwave plasma deposition. Various deposition conditions, such as bias voltage and methane atmosphere concentration, affect the purity of the diamond film. This analysis reveals sp2 bonding concentrations in these samples from, typically, a few percent to 25%.
| Identifer | oai:union.ndltd.org:USASK/oai:usask.ca:etd-07202005-125140 |
| Date | 22 July 2005 |
| Creators | Hamilton, Trenton David |
| Contributors | Moewes, Alexander, Manson, Alan, Johanson, Robert E., Hirose, Akira, Chang, Gap Soo, Bradley, Michael P. |
| Publisher | University of Saskatchewan |
| Source Sets | University of Saskatchewan Library |
| Language | English |
| Detected Language | English |
| Type | text |
| Format | application/pdf |
| Source | http://library.usask.ca/theses/available/etd-07202005-125140/ |
| 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 University of Saskatchewan 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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