本研究針對太陽能電池之本質矽薄膜層，其製程係以物理氣相沉積法之 脈衝直流磁控濺鍍系統，在不同通氫量條件下製備，並觀察分析和討論其 光電特性，如光學吸收係數、光學能隙、膜內矽氫及矽氧鍵結、氫原子含 量比例及材料的光學常數等，且分析不同通氫量製鍍條件之下對於光電特 性的影響。 由於矽薄膜有明顯光學干涉現象，在光學吸收係數的分析上易受干擾， 因此引入多光束干涉的理論做相關吸收係數的模擬，以求得近似實際吸收 係數的值。另外，本論文探討含氫矽薄膜材料之光學能隙的大小，在非晶 態時，隨通氫量增加而增加，經分析發現內部孔隙產生的結構改變是造成 上述結果的可能原因。而在分析矽薄膜材料於近紅外區的吸收趨勢，我們 架設一套常數光電流量測系統，來量測並分析薄膜中關於缺陷影響及能隙 等重要訊息，如非晶矽的缺陷密度特性以及微晶態的實際能隙值之求得， 並將以上結果做相關的比較和分析。In this article, we discuss our research regarding the intrinsic layer of solar cells. In this study we utilized pulsed DC magnetron sputtering for the PVD fabrication process as this was the more environmentally sound method. We looked at the relationship between the photonic properties and the hydrogen flow adjusting the amount of hydrogen flow. For example, the absorption coefficient of the materials, optical band gap, optical constants, bonding characteristics and even the percentage of hydrogen atom in the thin films were all subjects of interest. Due to interference effect in silicon thin film, we applied the multiple-beam interference theory into simulations for getting the nearly realistic absorption coefficients. Then we not only obtained optical absorption coefficients that were quite close to their actual value, but also gave attention to and discussed some theoretical reasons regarding the optical band gap shifting results. For example, silicon during in amorphous type had the increasing optical band gap when raising hydrogen flow. And we deduced the possible reason that structural variation of silicon thin film affected by voids. Moreover, we set up a system using the constant photocurrent method to analyze the absorption trend of the intrinsic silicon thin film in the infrared region. Additionally we discussed important analyses and comparisons regarding the effects of potential defects and the optical band gap of silicon film as a whole as shown by the measuring system, for example, defect density of amorphous silicon film and actual optical band gap of microcrystalline silicon film would also be realized via the method.
