以矽硼合金靶製作異質接面太陽能電池

Fabrication of P type Hydrogenated Silicon Thin Films Applied to Heterojunction Solar Cell Using Silicon-Boron alloy target

李京樺(Ching-Hua Li)

指導教授 ： 陳昇暉

國立中央大學/理學院/光電科學與工程學系/碩士(2014年)

摘要

本研究旨在探討以矽硼合金靶應用於濺鍍製程製作異質接面太陽能電池的可行性。濺鍍製程方式對於環境較友善，且於製程中不需要通有毒氣體，機台維護成本相對化學氣象沉積方式也來低，故本研究選用濺鍍的方式。然而濺鍍製程方式相較於化學氣象沉積方式薄膜摻雜果較差，使得薄膜電性不好，為了要改善以上情況濺鍍製程方式需要更多的摻雜才可達成。由文獻提到，濺鍍P-type矽薄膜時可於矽靶上放置硼顆粒提高薄膜的摻雜。故本實驗室團隊原先也是採用此方式幫助薄膜摻雜，應用於異質接面太陽能電池的製作。在本實驗室團隊多年來的努力之下，此製程方式有不錯的成果進展，然而此方式尚有製程穩定性、均勻性等因素考量。故本實驗團隊決定將優化的硼顆粒擺放方式應用於矽硼合金靶製作，看是否能改善以上缺點且製作出效率不錯的元件。
經過不斷修正本實驗最終使用三種不同濃度的矽硼合金靶分別鍍製P-type矽薄膜做薄膜特性的分析，以及應用於異質接面太陽能電池的製作。本研究結果以矽硼合金靶濃度(Si:wt90.7% B:wt9.3%)製作元件，元件有最佳的效率可達11.76%、開路電壓524mV、短路電流31.5 mA/cm2 與填充因子(FF)71%。

關鍵字

氫化P矽薄膜 ； 異質接面太陽能電池 ； 矽硼合金靶

並列摘要

The aim of this research is the fabrication of P-type hydrogenated silicon thin films and silicon heterojunction solar cells by using silicon boron target. A sputtering process produces less environmental pollution and costs less fabrication cost than a CVD process. In addition, the sputtering process is a nontoxic process. So we use sputtering method to fabricate solar cells in our research. However, the disadvantage of PVD sputtering process is low doping efficiency resulting in poor electrical properties for P-type silicon thin film. It has been reported that to improve the doping efficiency , the more dopant such as boron grains placed on silicon target is necessary. In this research, the same method was applied to manufacture heterojunction solar cells. The heterojunction solar cells can achieve good efficiency, however there are still some problems such as the stability and the uniformity. To overcome the problems the silicon target with boron grains was replaced by silicon boron alloy to manufacture heterojunction solar cells.
In this research, three different concentrations of silicon boron alloy targets were used to deposit the P-type silicon thin films, and manufacture heterojunction solar cells. The results show that the best device performance was achieved with conversion efficiency 11.76%, open-circuit voltage 524 mV, short-circuit current 31.5 mA/cm2, and fill factor 71% by silicon boron alloy target(Si:wt90.7% B:wt9.3%).

並列關鍵字

P type Hydrogenated Silicon Thin Films ； Heterojunction Solar Cell ； Silicon-Boron alloy target

參考文獻

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