photoluminescence, electron-phonon coupling, ZnO
洪聖傑1*, 何易恒1, 謝至中1, 盧芝佑1, 趙君棟1, 黃玉林*2
1物理系應用物理碩士班, 國立東華大學, 花蓮縣壽豐鄉, Taiwan
2物理系, 國立東華大學, 花蓮縣壽豐鄉, Taiwan
* presenting author:洪聖傑,
Zinc oxide (ZnO) is a polar semiconductor having a wide direct bandgap Eg=3.37eV at roomtemperature. The exciton binding energy as high as 60meV and strong electron-phononinteraction lead to advantageous optical and optoelectronic properties, making ZnO a highlyattractive candidate material for developing novel photonic devices. Recent researchesshowed that formation of mesoscopic structures provides possibilities of tuning the intrinsicoptoelectronic properties based on confined carries and phonons and/or their interactions. Inthis study, ZnO nanocrystalline films were grown by reactive sputtering followed by thermalanneals. The temperature dependence of ultraviolet-excited luminescence has been studied,showing significant phonon-replica features at low temperatures and dominance of freeexcitons at high temperatures. Optical quench of the excitonic emission was found to exhibit anon-monotonic temperature dependence. Possible quench mechanisms will be discussed

Keywords: photoluminescence, electron-phonon coupling, ZnO