本論文旨在利用水熱法(Hydrothermal Growth, HTG)成長氧化鋅(ZnO)奈米管(nanotubes、NTs)於太陽能電池表面再利用PECVD沉積氮氧化矽於氧化鋅奈米結構表面，製備出具表面粗化與折射係數漸變之結構，提升太陽能電池之入光量進而提升光電轉換效率。
本研究架構分為兩個部分，第一部分以理論模擬分析為主，係透過光學模擬軟體(TracePro)，分析不同氧化鋅奈米結構及包覆不同厚度之氮氧化矽於氧化鋅奈米管對傳統太陽能電池之入光量影響。由模擬結果顯示，在奈米管直徑寬度為100 nm、長度為400 nm且氮氧化矽沉積厚度為150 nm之結構於太陽能電池表面有最佳之入光能量。第二部分則著重於實驗之進行，本論文使用水熱法成長氧化鋅奈米線於傳統太陽能電池表面，再利用室溫之逆反應形成奈米管結構，最後使用PECVD沉積氮氧化矽作為折射係數漸變層。由實驗結果顯示，於奈米管直徑寬度為100 nm、長度為400 nm且氮氧化矽厚度為150 nm之結構於太陽能電池與傳統太陽能電池比較，其光電轉換效率增加39.2%。
模擬與實驗結果顯示，本論文所提藉由氧化鋅奈米結構之表面粗化與折射係數漸變層確實可降低光線反射率與菲涅耳損失，增加光電轉換效率。本論文所提氮氧化矽包覆氧化鋅奈米管結構於提升太陽能電池或其他光電元件效率極具應用潛力。

The present thesis is devoted to improve light absorption and efficiency using a ZnO/SiON-based refractive-index-matched (RIM) surface-roughening structure. The ZnO nanowires (NWs) and nanotubes (NTs) were first hydrothermally synthesized on regular solar cells (SCs)as a surface-roughening structure. And a SiON film was deposited on the surface of NTs by PECVD to form a surface roughening structure with a graded refractive index.
In the first part of this thesis, an optical simulating software, TracePro, was used to simulate the size effects of nanostructure and SiON/ZnO NTs on light absorption of SC. According to calculated results, it indicates that a RIM structure with a 150-nm-thick SiON film and nanotubes arrays with 100-nm-width and 400-nm-length in size could have the largest improvement in the cell efficiency for about 39.2%. Experimental study is presented in the second part of the thesis. ZnO nanostructures and SiON/ZnO NTs were implemented on regular SCs. Material analysis including surface morphology, components, and photoelectrical properties of the prepared SCs are examined and results are presented and discussed.
In summary, the effectiveness of SiON/ZnO NTs RIM structure surface roughening scheme in improving efficiency of SCs has been studied and demonstrated theoretically and experimentally. The proposed RIM structure with a 150-nm-thick SiON film and NTs structure with 100-nm-width and 400-nm-length in size has shown an improvement in the cell efficiency by 39.2% as compared with the regular SC. It is expected that the RIM SiON/ZnO nanotubes structure proposed in the present thesis could be applied for optoelectronics to minimize the Fresnel loss and maximize photoelectric efficiency.

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