本論文主要目的是研製奈米晶粒矽 (nc-Si:H) p-i-n 太陽能電池。首先是利用四種不同的製程方法製備所要的nc-Si:H薄膜: (1)在PECVD系統的陰極加裝不銹鋼網； (2) 先在基板上成長一層a-Si:H緩衝層，再沉積nc-Si:H薄膜； (3) 先使用氫電漿處理a-Si:H緩衝層後，再沉積nc-Si:H薄膜； (4) 用氫氣稀釋源氣體SiH4的方式沉積nc-Si:H薄膜。我們也使用微拉曼光譜儀 (micro-Raman spectroscopy)、X光繞射儀 (XRD) 及場發射掃描式電子顯微鏡(FE-SEM) 等儀器分析各nc-Si:H薄膜的結晶度。測量結果顯示，先在基板上沉積一層緩衝層，再用氫電漿處理緩衝層的表面，而後配合適當的SiH4濃度，可沉積出較佳的矽奈米晶粒 (nc-Si:H) 薄膜。
再者，我們也利用上述較佳的製程參數，製備了二種不同結構的太陽能電池並量測其短路電流、開路電壓、填充因子及轉換效率。第一個元件的結構是Al / n-a-Si:H / i-a-Si:H / p-a-SiC:H / ITO /glass，另一個元件的結構為Al / n-a-Si:H / i-nc-Si:H / i-a-Si:H ( buffer layer )/ i-a-Si:H / p-a-SiC:H / ITO /glass。實驗結果顯示，在AM1.5之下，前者有比較好的轉換效率 (1.08%) ，而後者具略高的填充因子 (0.278)。

In this thesis, the fabrication process and performance of the nanocrystalline silicon (nc-Si) p-i-n solar cells was studied. Firstly, the nc-Si:H films were deposited with a PECVD (plasma-enhanced chemical vapor deposition) system, by employing four different process techniques: (1) attaching a stainless steel mesh to cathode of the PECVD system, (2) an a-Si:H buffer layer was deposited on the substrate before growing the nc-Si:H film, (3) applying additional in-situ H2-plasma treatment on the a-Si:H buffer layer before growing the nc-Si:H film, and (4) the SiH4 reaction gas was diluted in H2 ,and the crystallinity of the obtain films were compared. The nc-Si:H films were characterized with micro-Raman spectroscopy, X-ray diffraction (XRD) and field-emission scanning electron microscope (FE-SEM). From the measurment results, it was concluded that depositing an a-Si:H buffer layer and then applying in-situ H2-plasma treatment on a-Si:H buffer layer could result in the better crystallinity of the grown nc-Si:H film.
Then, two different structures of nc-Si:H p-i-n solar cell were fabricated and their characteristics such as the short-circuit current ( Isc ), open-circuit voltage ( Voc ),fill factor ( FF )and efficiency ( eff. ) were measured. For the device structures, one was Al / n-a-Si:H / i-a-Si:H / p-a-SiC:H / ITO (indium tin oxide) /glass and the other was Al / n-a-Si:H / i-nc-Si:H / i-a-Si:H ( buffer layer )/ i-a-Si:H / p-a-SiC:H / ITO /glass. The measured results showed that the former one had a higher efficiency (~ 1.08%) and the later one had a little higher FF (~ 0.278) under AM1.5.

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