Photo reflectance¡]PR¡^ and Contactless electroreflectance¡]CER¡^spectra of Zn and O-faces of a c-plane ZnO bulk have been measured at room temperature, respectively. It was found that the phase of PR is the same as that of CER for the Zn-face and they are inverted for the O-face. This indicates a polarization induced field existing in the c- plane ZnO bulk due to nonzero spontaneous polarization. In addition, a mercury lamp was focused on the ZnO sample in the CER measurements to provide a photovoltaic voltage to reduce electric field in the sample. The CER spectrum with Hg lamp is more blue-shifted and its amplitude is smaller than that without Hg lamp. Hence, the type of transitions was classified as excitonic transition. The A, B, and C excitonic transition energies were obtained by fitting experimental spectra.
| Identifer | oai:union.ndltd.org:NSYSU/oai:NSYSU:etd-0705111-125111 |
| Date | 05 July 2011 |
| Creators | Cheng, An-hao |
| Contributors | Yung-Sung Chen, Dong-Po Wang, Yan-Ten Lu |
| Publisher | NSYSU |
| Source Sets | NSYSU Electronic Thesis and Dissertation Archive |
| Language | Cholon |
| Detected Language | English |
| Type | text |
| Format | application/pdf |
| Source | http://etd.lib.nsysu.edu.tw/ETD-db/ETD-search/view_etd?URN=etd-0705111-125111 |
| Rights | not_available, Copyright information available at source archive |
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