旋轉塗佈摻雜溶液之擴散製程探討及其應用 於製備太陽能電池

Development of silicon solar cells using spin-on dopants

胡致維(Jhih-Wei Hu)

指導教授 ： 陳一塵

國立中央大學/工學院/材料科學與工程研究所/碩士(2014年)

摘要

能源問題日漸受到大家重視，為了供給足夠的能源來因應人類的需求，然而許多能源都需要嚴重的代價如環境污染；而太陽能電池為一潛力再生能源之一。為了降低太陽能成本及有效增加太陽能效率，本篇用磷酸、硼酸作為擴散源；傳統POCl3和BBr3為典型擴散常用的溶液；三溴化硼（BBr3）、氧氯化磷(POCl3)皆為劇毒且BBr3具有自燃的特性，因此本篇利用硼酸(H3BO3)、磷酸(H3PO4)在去離子（DI）水的稀釋下，進行高溫擴散並討論擴散後的特性，期望利用廉價和無毒性替代了傳統的硼擴散源。
我們利用硼酸溶液和磷酸溶液作為擴散源，並經由高溫擴散在矽基板，探討在高溫下的去疵效果、片電阻、擴散深度；其中硼酸濃度在(0.5-6wt%)作高溫擴散；而磷酸(0.1-3.5 vol%)，經由WCT-120量測少數載子壽命、暗示電壓和霍爾分析量測片電阻。硼酸溶液(〜0.5-6wt%)、磷酸溶液(〜0.1-3.5vol%)作為高溫擴散後有廣泛的片電阻（〜4 - 20Ω/sq）、(~5 - 40Ω/sq)。此外我們選定做一固定溶液濃度下進行不同溫度擴散(850℃~1050℃)，得到最佳吸附雜質的擴散溫度。
最後我們結合不同條件，將研究結果應用在單晶N型矽太陽能電池上，目前初步得到太陽能電池轉換效率(η) = 13.13 %；開路電壓(Voc ) = 580.40mV；短路電流(Jsc) = 34.07 mA/cm2；填充因子(FF) = 65 %。

關鍵字

旋轉塗佈摻雜溶液之擴散製程探討及其應用 於製備太陽能電池

並列摘要

In this thesis, dilute spin-on solutions of boric acid and phosphoric acid in de-ionized (DI) water, low-cost and non-toxic alternative to more conventional boron diffusion sources like boron tribromide (BBr3) which are toxic and pyrophoric. It was found that boron emitters with a wide range sheet resistances (~4 – 20 Ω/sq.) could be achieved with very dilute boric acid sources (~0.5-6 wt.% boric acid in DI water) by controlling the diffusion time and temperature.
We have studied the application of annealing processing for boron and phosphorus diffusion using spin-on dopants (SODs). For the diffusion, an extended gettering process, both P and B diffusion at 850oC、900oC、950oC、1000oC、1050oC followed by in-situ gettering at different temperature for one hour, gave better lifetime values than the standard gettering for all compensation levels. The lifetime of highly compensated materials were increased significantly by such an extended gettering process. Cell efficiency up to 11.9 % has been achieved on 1x1cm2 cells with the boron emitter and the phosphorus BSF formed with boric acid and phosphoric acid, respectively.
Finally, we fabricate monocrystalline N-type silicon solar cell get the optimized result, and there we have the electro-optic convert efficiency = 13.13%, the open-circuit voltage (Voc) = 580.40 mV, short-circuit current density (Jsc) = 34.07 mA/cm2, and the fill factor (FF) = 65%.

並列關鍵字

Development of silicon solar cells using spin-on dopants

參考文獻

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