Study of optical properties of nonpolar GaN and nonpolar ZnO
碩士 === 國立中山大學 === 物理學系研究所 === 101 === We use a Ti:sapphire femtosecond laser and a Time Correlated Single Photon Counting (TCSPC) system to study optical properties and carrier relaxation of Two-step M-Plane GaN epitaxial layers grown on LiAlO2(100) by plasma-assisted molecular-beam epitaxy and a A-...
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| Format: | Others |
| Language: | zh-TW |
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2013
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| Online Access: | http://ndltd.ncl.edu.tw/handle/r9x2gm |
| Summary: | 碩士 === 國立中山大學 === 物理學系研究所 === 101 === We use a Ti:sapphire femtosecond laser and a Time Correlated Single Photon Counting (TCSPC) system to study optical properties and carrier relaxation of Two-step M-Plane GaN epitaxial layers grown on LiAlO2(100) by plasma-assisted molecular-beam epitaxy and a A-Plane ZnO epitaxial layers grown on M-Plane Sapphire by plasma-assisted molecular-beam epitaxy.
We change the temperature of the sample from 14 K to 300 K, the near-band-edge emission is red-shifted as temperature increase. We measured the samples of different N/Ga ratio and N plasma power. We found the defect peak will become obvious when the N/Ga ratio and N plasma power increases. Because N/Ga ratio is higher, the stacking faults will be more rich. Besides, we investigate the relationship between polarization of photoluminescence. We found the PL intensity would become stronger as the polarization of photoluminescence perpendicular to c-axis of sample. We found the lifetime of carrier recombination would increase as wavelength increase and temperature decrease.
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