次波長抗反射結構製作及增進砷化鎵太陽能電池發電效率

Fabrication of Sub-wavelength Antireflective Structure Enhancing the Efficiency of GaAs Solar Cells

張哲郡(Che-Chun Chang)

指導教授 ： 李有璋

中原大學/工學院/機械工程研究所/碩士(2012年)

https://doi.org/10.6840/cycu201200657

摘要

當一太陽光入射太陽能電池表面時，會因空氣與太陽能電池表面材料折射率的差異而產生菲涅爾損耗(Fresnel loss)，使得太陽能電池的光電轉換效率不盡理想，導致發電成本提高，阻擋了太陽能電池在日常生活中的普及性。次波長週期性結構不僅具有優秀的抗反射效果，比起傳統抗反射膜也具有更多優點，例如良好的疏水性、抑制波長與光線入射角度的範圍較寬。
　　本論文利用聚苯乙烯奈米球微影與奈米壓印技術製作週期性次波長結構於砷化鎵太陽能電池表面，目的是希望能夠降低表面反射率，提升太陽能電池的光電轉換效率。本實驗使用直徑600 nm的聚苯乙烯奈米球塗佈在矽與砷化鎵基板上作為蝕刻擋層，利用感應耦合電漿(ICP)與高密度電漿(HDP)蝕刻系統製作出不同形狀高度的抗反射結構並使用紫外/可見與紅外光分光光譜儀量測其反射率。以此種結構圖型為母模具翻製出聚二甲基矽氧烷(PDMS)軟性模具，最後再以此軟性模具壓印折射率材料於太陽能電池表面形成週期性次波長的抗反射結構。在AM1.5光源量測下，短路電流與光電轉換效率分別得到14.7 %與5.04 %的提升。

關鍵字

次波長抗反射結構 ； 奈米壓印 ； 電漿蝕刻 ； 奈米球微影

並列摘要

When sunlight incident on the surface of solar cell, Fresnel loss occurs at the air-solar cell’s material interface due to the refractive index difference across the interface. Fresnel loss reduces the photoelectric conversion efficiency and also increases power generation cost, which hinders wide use of solar cells. Compared with conventional anti-reflection (AR) coating, sub-wavelength structures (SWSs) not only has anti-reflective effect, but also apply to wide angle of light incident at broadband wavelength. SWSs normally has a good hydrophobicity
　　In this study, various surface morphology sub-wavelength structures were successfully fabricated on Si and GaAs substrate using polystyrene spheres lithography in conjunction with inductive coupling plasma (ICP) and high density plasma (HDP) etching processes. UV-vis-IR spectrometer was used to measure the reflectivity of various SWSs compared with the simulation results. SWSs were then fabricated on GaAs solar cell to reduce the surface reflectivity and enhance the photoelectric conversion efficiency by nano-imprinting process. Compared with the GaAs solar cell without anti-reflective film, the results show that the short circuit current (Isc) and photoelectric conversion efficiency (Eff) increased 14.7 % and 5.04 %, respectively.

並列關鍵字

nano-imprint ； sub-wavelength structures ； anti-reflection ； polystyrene spheres lithography

參考文獻

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