高穩定性及高效率矽薄膜太陽能電池

Abstract

此論文將介紹我們利用高密度電漿化學氣相沉積系統(HDP-CVD)開發低溫、低成本、高品質之矽薄膜技術，並發展可撓式非晶矽薄膜太陽能電池。首先，我們找出最佳適用於太陽能電池的非晶矽薄膜並對它們的光性及結構進行分析。使用E04模型及托克模型來分析非晶矽的光能隙，皆位於1.5eV至2.0eV之間，而拉曼光譜峰值位為476 cm-1，由此可驗證我們的矽薄膜皆為非晶矽結構。之後，我們成功地在玻璃基板上整合成p-i-n及n-i-p非晶矽薄膜太陽能電池元件，隨著沉積p-layer時B2H6摻雜氣體流量的提升，開路電壓可提升至0.91伏特，轉換效率則可達9.6%。此外，我們成功地在可撓式基板(polyimide)上製作n-i-p非晶矽薄膜太陽能電池，初始轉換效率可達3.89%。由於這些低的熱預算和高沉積速率薄膜技術，開啟了高效率可撓式多接面太陽能電池的可行性。

This article introduce that we utilize high density plasma chemical vapor deposition (HDPCVD) to develop low cost, low temperature, high quality silicon thin film deposition technique and high efficiency flexible amorphous silicon thin film solar cell. At first, we optimized the condition of silicon thin films and then analyze the optical and structural characteristics of these films. The optical band-gap of silicon thin films were evaluated by E04 model and Tauc model respectively, which were in the amorphous silicon band-gap range. Raman spectra of the un-doped a-Si:H with the lower rf power, and a peak was observed at 476cm-1 which is typical for amorphous network. After that, we successfully fabricated p-i-n and n-i-p amorphous silicon thin film solar cell device on glass substrate. With increasing the boron doping concentration in the p-type a-Si:H window layer, the open-circuit voltage was improved to 0.91V and efficiency was improved to 9.6%. Additionally, we successfully fabricated a-Si:H thin film n-i-p solar cell on flexible substrate(polyimide) with initial conversion efficiency 3.89%. Such thin film technique features low thermal budget and high deposition rate, which opens the feasibility of the high efficiency flexible multi-junction solar cells.