白光偏壓對空間電荷限制光伏元件量子效率之影響

Effects of White Light Bias on Incident Photon-to-Electron Collection Efficiency Measurement of Space-Charge-Limited Photovoltaic Devices

陳俊男(Chun-Nan Chen)

指導教授 ： 洪勝富

國立清華大學/電機資訊學院/電子工程研究所/碩士(2012年)

摘要

本研究探討空間電荷限制光伏元件正確的光電轉換效率（Incident photon-to-electron conversion efficiency, IPCE）量測方式，主要量測以P3HT與PCBM混合作為主動層之有機高分子太陽能電池。因為有機高分子材料受空間電荷限制電流（space charge limit current, SCLC）效應影響，導致有機高分子太陽能電池之電流對光強度關係為非線性關係，使用微弱單頻光的一般IPCE量測方法無法精確得到有機高分子太陽能電池真實的IPCE，因此在IPCE量測系統外加白光作為光偏壓，使元件操作於高光強下進行IPCE量測。因為白光是由許多波長組合而成，能否正確地使用作為光偏壓是個需驗證的問題；本文使用藍光、綠光和橘光發光二極體 （light-emitting diode , LED）驗證白光對元件的影響是否等效特定波長對元件的影響。
使用兩種正結構元件與兩種反結構元件驗證白光作為光偏壓的正確性；照光強度越強會使得SCLC效應越明顯導致IPCE值下降；由實驗結果可知白光可正確作為光偏壓而且量測有機高分子太陽能電池真實IPCE時必須使用白光光偏壓。

關鍵字

有機太陽能電池 ； 光電轉換效率 ； 空間電荷限制

並列摘要

We developed an easy and accurate method for incident photons-to-electrons conversion efficiency（IPCE）measurement of space-charge-limited (SCL) photovoltaic devices. An extra white light bias is usually introduced in IPCE system to obtain the correct IPCE of SCL devices since the relationship between current and incident light intensity is nonlinear. However, the validity and nessecity of the extra light bias requires further proof. Therefore, we used blue, green and orange light-emitting diode (LED) to verify the validity and nessecity.
The validity and necessity of white light bias were examined in both conventional and inverted organic solar cell. The white light is proven be valid as light bias correctly and necessary in the IPCE measurement system to obtain the accurate IPCE of SCL photovoltaic devices from the experiment results. SCL effect also appears to be more significant under stronger light illumination.

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