用奈米小球微影法製作多晶矽太陽能電池表面結構

Surface structures of polycrystalline silicon solar cell fabricated by nano-sphere lithography

陳煒(Wei Chen)

指導教授 ： 李正中 ； 陳昇暉

國立中央大學/理學院/光電科學研究所/碩士(2011年)

摘要

本研究使用奈米小球微影法在單面拋光多晶矽基板上以乾蝕刻的方式蝕刻出錐狀、柱狀及子彈狀結構。接著利用原子層沉積法在反射損耗較低的子彈狀結構表面鍍一層抗反射膜，以降低表面反射率。在量測分析上利用量測基板的反射率來討論不同形貌的結構對光學特性的影響。最後，我們將製程方法使用在非拋光多晶基板上以降低太陽能電池生產成本。
實驗結果發現不同高度的錐狀及柱狀結構，高度越高具有較低的反射率。相同高度不同頂角的子彈狀結構，頂角越小則具有較低的反射損耗。子彈狀結構相較於錐狀及柱狀具有較低的反射率，而ZnO抗反射膜可將波長300~1000nm平均反射率可降至0.69%。在光以大角度入射時也有極佳的抗反射效果。在光60度角入射時，波長400~850nm的平均反射率低於3%，其優化的光電流可達到36.55mA/cm2。將製程參數使用在非拋光基板上時，在波長300~1000nm的平均反射率為1.72%。在光60度角入射時，平均反射率達到3.39%，其優化的光電流可達到36.18 mA/cm2。

關鍵字

有限時域差分法 ； 原子層沉積 ； 奈米小球微影法

並列摘要

In this research, three types of nanostructures including cone, frustum, and bullet structures have been fabricated using nanosphere lithography on polycrystalline silicon substrates. Then, an antireflection coating (ARC) of ZnO film was deposited on the nanostructure using atomic layer deposition (ALD) process to reduce surface reflection. The reflectivity of the substrates with the different nanostructures was measured to investigate the relationship of the reflectivity with both depth and shapes. Finally, the nanosphere lithography technique was applied to the non-polished polycrystalline silicon substrate for the cost reduction of the solar-cell mass-production.
The results show, the average reflectance of the cone and frustum structures decreased as the height increasing. The average reflectance of the bullet structures decreased as the vertex angle decreasing. The reflectance of Bullet structures is lower than the reflectance of cone and frustum structures.
When the nanosphere lithography was applied to the polished polycrystalline silicon substrates, the average reflectance is 0.69% in the spectral range of 300~1000nm for the incident angle of 8o. The average reflectivity is less than 3.0% in the incident angle less than 60o in the spectral range of 400~850nm. At that moment the short-current is arrived 36.55mA/cm2.
When nanosphere lithography was applied to the non-polished polycrystalline silicon substrates, the average reflectance is 1.72% in the spectral range of 300 ~1000nm for incident angle of 8o. The average reflectivity is less than 3.39% in the incident angle less than 60o in the spectral range of 400 ~ 850nm. At that moment the short-current is arrived 36.18mA/cm2.

並列關鍵字

nano-sphere lithography ； atomic layer deposition ； finite difference time domain method

參考文獻

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