近年來在介電材料中形成含有磷或硼摻雜的奈米矽晶在光電元件、記憶體或是第三代太陽能電池上的應用皆受到相當大的關注。然而因為尺寸和高表面積與體積比，因此要在奈米矽晶中順利形成摻雜並非易事。而目前在製備含磷摻雜奈米矽晶的方法主要以濺鍍法或電漿輔助化學氣象沉積法再搭配高溫退火處理。而因電子迴旋共振化學氣象沉積(electron cyclotron resonance chemical vapor deposition, ECRCVD)相較於傳統的PE-CVD而言有沉積速率較快速、低離子轟擊、無電極汙染、較高的氣體使用率等優勢，因此本研究以ECR-CVD成長磷摻雜過飽和氧化矽薄膜(Si-rich oxide films)並以高溫熱退火處理使其在過飽和氧化矽薄膜中形成含磷摻雜之奈米矽晶，探討薄膜特性及其應用在矽基異質接面薄膜太陽能電池的表現。
本研究將針對高溫退火後所析出之含磷摻雜奈米矽晶薄膜以UV-Visible、Raman、XPS等儀器分析薄膜之吸收率、結晶性及原子鍵結型態。探討在通入不同CO2/SiH4和PH3/SiH4的氣體比例下，可得到薄膜整體吸收低於20 %，且導電率在10-1 Ω-1 cm-1。再針對磷摻雜的濃度做優化，將薄膜研究結果應用在異質接面太陽電池上，在氧/矽比不同和有無外加透明導電膜(ITO)的條件下，用快速退火爐對電極進行低溫退火處理。目前初步得到太陽電池的轉換效率(η) = 6 %；開路電壓(Voc) = 490 mV；短路電流(Jsc) =17.51 mA；填充因子(FF) = 70.5 %。

In recent years, fabrication of nanocrystalline silicon containing phosphorus or boron doped embedded in dielectric materials have attract many attentions because its potential such as in the optoelectronic components, memory or third-generation solar cells. However, doping of nanocrystals is not easy to be achieved due to their small size and large surface-to-volume ratios. At present, the method of preparation of phosphorus-doped silicon nanocrystals were sputtering or plasma-enhanced chemical vapor deposition with high-temperature annealing treatment. Compare to conventional PE-CVD, ECR-CVD have higher deposition rate, lower ion bombardment, no electrode contamination, higher gas usage and other advantages. In this study, electron cyclotron resonance chemical vapor deposition (ECR-CVD)were used to growth phosphorus-doped Si-rich oxide films, and to explore the film characteristics and the performance of silicon heterojunction thin film solar cells.
In this study, we present a fabrication method for p-doped Si-NCs embedded in silicon oxide by thermal annealing of heavily P-doped hydrogenated amorphous silicon oxide (a-SiO:H) films grown by electron cyclotron resonance chemical vapor deposition (ECRCVD). The electrical and optical properties of the annealed films were investigated. Finally, we fabricate heterojunction cell with the optimized recipe of the window layer from the result that we investigated, and there we have the Electro-optic convert efficiency 6%, the open-circuit voltage (VOC) = 490 mV, short-circuit current density (JSC) = 17.51 m A/cm2, and the fill factor (FF) = 70.5%.

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