非晶矽基太陽能電池一般是利用電漿增強式化學氣相沉積系統(Plasma Enhanced Chemical Vapor Deposition, PECVD)進行薄膜沉積，過程中基板溫度必須維持在250 ℃，否則薄膜會產生劣化等相關問題，因此在軟性基板選用上，耐熱溫度可在250 ℃以上是基本要求。聚亞醯胺(Polyimide, PI)可作為軟性基板，具有可耐高溫至320 ℃、抗酸鹼能力佳及易撓曲的特性，因此本研究使用Polyimide作為塑膠軟性基板，並以倒置的n-i-p結構將非晶矽薄膜太陽能電池沉積在Polyimide塑膠軟性基板上，最後鍍製出高效率且可彎曲的串疊太陽能電池。
本研究首先將n-i-p結構太陽能電池成長於玻璃上，由於成長表面的差異性，導致沉積出來的p型非晶矽薄膜品質較差，降低整體太陽能電池轉換效率。因此，本研究利用氫氣電漿處理分別於i/p接面及p/ITO接面做處理，以減少薄膜表面懸鍵並提升後續薄膜沉積的品質。最後鍍製出轉換效率3.27 %之n-i-p結構非晶矽太陽能電池於可撓基板，並有效改善元件之特性。再將最佳化條件轉移至Polyimide塑膠軟性基板上，並與矽鍺電池作串疊，鍍製出效率4.26 %的氫氣電漿處理n-i-p-n-i-p結構非晶矽/矽鍺串疊薄膜太陽能電池於可撓式基板。最後改變不同彎曲次數及曲率半徑，分析不同彎曲條件下對於矽基可撓式薄膜太陽能電池的影響。

關鍵字:非晶矽; 氫氣電漿處理; 串疊; 矽鍺

Amorphous silicon-based Solar cells are generally deposited by plasma enhanced chemical vapor deposition (PECVD) with substrate temperature 250 ℃ during the process. In this study, n-i-p structure was used to fabricate silicon-based solar cells on Polyimide (PI). However, this structure may cause poor quality and numerous surface states in the a-Si films. The H2 plasma passivation is a promising technique to improve the amorphous silicon (a-Si) solar cells. The method enhanced the efficiency of a-Si solar cells from 1.25 % to 4.22 % on glass substrate. In addition, the efficiency of flexible a-Si solar cell deposited on PI was 3.27 %. In order to further enhance the efficiency, the a-SiGe cell with absorption of infrared was combined with a-Si cell as double junction tandem solar cells. The efficiency of a-Si/a-SiGe tandem solar cells with H2 plasma passivation is 6.03 % and 4.26 % on the glass and PI substrate, respectively. Furthermore, the durability of tandem solar cells on PI was analyzed by different degree of bending and bending times.

Key words：H2 plasma passivation, amorphous silicon, flexible, tandem solar cells.

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