本篇論文在探討奈米線/金字塔結構對矽基太陽能電池之影響。製程上以金字塔為主要結構，並蝕刻具有良好抗反射特性之奈米線結構，再利用溶膠凝膠法調配磷擴散溶液，以及使用網版印刷技術製做電極，其優點為製程簡單、成本低、減少環境危害。

本實驗在金字塔結構上又可以分為無研磨處理及三種研磨前處理，在無研磨處理情況下所蝕刻之金字塔形貌相當不均勻，最佳擴散後反射率為21.86%，效率為7.05%。而三種研磨方式分為鑽石粉研磨、砂紙研磨及拋光膏研磨，其目的在於蝕刻出均勻形貌金字塔結構，降低反射率以提高效率。三種研磨製程以拋光膏研磨有最好之效果，擴散後反射率為15.73%，效率為8.52%。

在奈米線/金字塔結構上，其最佳擴散後反射率為9.68%，最佳效率10.57%。而經過研磨處理所蝕刻之小尺寸金字塔，因為在擴散去氧化完後所對結構造成的破壞較大，因此其奈米線/金字塔結構效率較低。另外改變其硝酸銀濃度，觀察奈米線疏密度對其元件性能之影響，發現濃度0.5mM所蝕刻出接近孔洞狀之奈米線形貌有最佳之效率10.94%。而為了追求更高效率，因此再改變蝕刻時間，發現45秒所蝕刻之結構有最高效率11.52%。

金字塔蝕刻奈米結構與單純金字塔結構相比可以有效降低反射率，並提高效率。對無研磨金字塔結構而言在硝酸銀濃度0.5mM蝕刻45秒，其反射率可下降至14.10%，轉換效率可提高至11.52%。

This paper mainly discusses the effect of si nanowire / pyramid structures on solar cell performance. Pyramid structure is used in this manufacturing process, and the nanowire structure is synthesized by using the metal assisted electroless etching technique which performed the excellent anti-reflective properties. This work uses the sol-gel method to prepare the diffusion solution, and the screen printing technique for metal electrode. This process possesses the simple, low cost, reduced environmental hazards in solar cell fabrication.

In this study, the pyramid structure can be divided into no polishing treatment and three kinds of polishing pre-treatment. In the case of no polishing, the pyramid morphology is showed non-uniform, and performed the best reflectance of 21.86% after diffusion, and the efficiency of 7.05%.The three kinds of polishing way are diamond powder polishing, sandpaper polishing and polishing paste polishing. These pre-treatment processes possess the uniform morphology of pyramid structure and the lower reflectivity which effectively improve the efficiency. In these three kinds of polishing way, the polish paste polishing exhibits the best results, the reflectance is 15.73% after diffusion, and the efficiency is 8.52%.

In the nanowire / pyramid structure, the best reflectance is 9.68% after diffusion and the best efficiency is 10.57%. For the small size of nanowire / pyramid structure which is synthesized after polishing treatment, it is observed greater damage on the structure after diffusion process. These kinds of the small size for nanowire / pyramid structure possess the worse efficiency of solar cell. Moreover, the nanowire / pyramid structure with various silver nitrate concentrations are also study. It is found that the concentration of silver nitrate with 0.5mM possess the best efficiency of 10.94% with the certain density nanostructure in pyramid. Furthermore, the influence of the depth for nanostructure with various etching time on solar cell efficiency is further investigated. It is found that the 45 seconds of etching time perform the maximum efficiency of 11.52%.

The pyramid with nanostructures compared with pyramid structure can effectively reduce the reflectivity, and improve efficiency. In the no polishing treatment pyramid structure, for the concentration of silver nitrate with 0.5mM and the etching with 45 seconds, the reflectivity can be reduced 14.10% and the efficiency increased to 11.52% .

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