以射頻磁控濺鍍方式鍍製含氫微晶矽薄膜並探討其應用於薄膜太陽能電池之可能性

Fabrication of Hydrogenated microcrystalline Silicon Thin Films Using RF Magnetron Sputtering

韓嘉緯(Jia-wei Han)

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

由於含氫之微晶矽薄膜比非晶矽薄膜的電性更佳，因而受到重視。製作含氫之微晶矽薄膜目前之主流製程為以電漿輔助之化學氣相沈積法(PECVD)。但PECVD的缺點在於設備成本高，且使用SiH4等有毒氣體。然而以射頻磁控濺鍍法來製作則可免除這些缺點，但很不幸地，一般以射頻磁控濺鍍法所製作出的都是非晶矽。因此本研究中，希望在較低之基板溫度條件下(Ts=250 ℃)，能使用氫氣混入氬氣之方式鍍製出含氫之微晶矽薄膜。吾對於以不同氫氣流量、電源功率和基板溫度所製作出之薄膜進行晶粒大小、結晶比例和電性(暗導電率、光導電率、光導電率和暗導電率之比值photosensitivities)之量測分析。實驗結果顯示，晶粒大小、結晶比例和導電率會隨著氫氣流量的增加而增加，而photosensitivities卻相對減少；當氫氣流量達到適量時，晶粒大小可達20nm，結晶比例可達到80%以上。

關鍵字

太陽能電池 ； 物理氣相沈積法 ； 微晶矽

並列摘要

Hydrogenated microcrystalline silicon (μc-Si:H ) thin films have attracted many attentions due to the high mobility compared with the amorphous silicon (a-Si) thin films. To fabricate μc-Si:H thin films 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). Whereas there is no these disadvantages using radio-frequency (RF) magnetron sputtering to deposit silicon thin films. Unfortunately, the silicon thin films deposited by the regular RF magnetron sputtering are a-Si. In this study, μc-Si:H thin films were fabricated using RF magnetron sputtering with argon and hydrogen as working gas at low substrate temperature (Ts=250℃). The grain sizes, crystal volume fractions and photosensitivities (ratios of dark conductivities and photo conductivities) of the μc-Si:H thin films which deposited with different hydrogen partial pressures and sputtering powers were analyzed. The results showed that the grain sizes and the crystal volume fractions were increased and the photosensitivities were decreased as the hydrogen gas flow increased. The grain sizes were between 15 to 20 nm and the crystal volume fractions were between 75 to 80% at high hydrogen gas flow .

並列關鍵字

microcrystalline Silicon ； PVD ； Solar cell

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