以脈衝直流磁控濺鍍法製作含氫非晶矽薄膜於太陽電池之應用

Fabrication of Hydrogenated Amorphous Silicon Thin Films Using DC-pulse Magnetron Sputtering

蘇韋寧(Wei-ning Su)

指導教授 ： 李正中

國立中央大學/理學院/光電科學研究所/碩士(2007年)

摘要

近年來，由於能源危機的問題，薄膜式太陽電池的研究引起很多專家學者的注意。目前最普遍為民生所使用的太陽電池是由電漿輔助化學氣相沉積法(plasma-enhance chemical vapor deposition, PECVD)所製作出的非晶矽薄膜太陽電池，但是PECVD在製程上需要昂貴的設備費及使用有毒、易燃氣體矽烷(silane, SiH4)，因此本研究主旨在探討使用脈衝直流磁控濺鍍製作含氫非晶矽薄膜應用於薄膜式太陽電池的研究。利用調變不同製程溫度、脈衝頻率與氫氣通量，製作出含氫非晶矽薄膜(a-Si:H)，並量測其特性。將實驗所製作出的薄膜量測XRD、FTIR、導電率，得到薄膜的結構、矽氫鍵結、導電率的結果，作分析與比較。
於實驗中發現，以脈衝儀直流磁控濺鍍系統所製作出的非晶矽薄膜，隨著氫氣通量的增加薄膜的R* (Microstructure factor)會增加，且在溫度由250℃升至350℃對於Si-H2鍵結比例無明顯影響，在氫氣通量8sccm以上，薄膜結構會趨向結晶。電性部分隨著氫氣量的增加，有照光與無照光的導電率都會上升，但是無照光的上升幅度比較大，造成photosensitivity下降，而非晶矽薄膜部分，photosensitivity有大多數皆超過103或104以上，可見此薄膜對於光照之後會有光起電效應作用，可應用於薄膜太陽電池的非晶純矽層(intrinsic layer, i-layer)。

關鍵字

薄膜 ； 濺鍍 ； 薄膜太陽電池 ； 非晶矽

並列摘要

In recent years, the researches of Thin Film Solar Cells attracted much attention for the reason of the energy crisis. To fabricate amorphous silicon thin film solar cells using plasma-enhance chemical vapor deposition (PECVD) is the most popular method. The disadvantages of PECVD are the high facility cost and using the toxic processing gases such as silane (SiH4). In this research, the hydrogenated amorphous silicon (a-Si:H) thin films for the application of thin thing film solar cell were fabricated using DC pulse magnetron sputtering with the different process temperatures, the DC pulse frequencies or the hydrogen gas flows and measured by using XRD,FTIR, conductivity measurement.
The results show that the microstructure factors(R*) of a-Si:H were increased when the hydrogen gas flow increased. And the concentration of Si-H2 bonds is not obviously change at high temperature (TS=350℃) or temperature (TS=250℃). According to the analysis of XRD, the a-Si:H films tend to crystallize when the hydrogen gas flow increased. Besides, the analyses of the electrical property show the dark and photo conductivity were increased and photosensitivities decreased when the hydrogen gas flow increased at all temperatures and pulse frequencies. Finally, the photosensitivities of the a-Si:H thin films are all higher than 103 or 104 which means that the a-Si:H thin films fabricated using DC pulse magnetron sputtering can be applied to the intrinsic layer of thin film solar cell.

並列關鍵字

amorphous silicon ； thin film ； solar cell

參考文獻

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