有機發光二極體及太陽能電池之研製

本論文研究方向有兩種：(1) 有機發光二極體(Organic Light Emitting diodes；OLED)方面：在陽極(ITO)圖案化之後，在陽極電極邊緣與有機層之間，分別使用PECVD鍍上不同厚度之SiO2，以及塗上不同厚度之光阻(photo-resistor)作為隔離層(isolation-layer)，以改善OLED之漏電流。漏電流(leakage-current)會使得載子(carrier)在發光區域周圍流失，造成電子電洞無法有效地在發光區域內結合，相對的元件發光效率也就比較差。實驗結果發現SiO2的厚度增加，漏電流明顯減少。當SiO2厚度由0 nm增加至250 nm，其元件發光效率(Luminance Efficiency)在電流密度為150 mA/cm2時，由1.7 cd/A提升至3.4 cd/A。最後，利用光阻作為隔離層，研究光阻厚度對阻隔元件漏電流之效果。當光阻厚度為2250 nm時，元件發光效率可再提升4.5 cd/A (at 150 mA/cm2)；(2)製作有機太陽能電池(Organic Solar Cells)方面：利用ZnPc作為有機太陽能電池中的電子施體層(Donor layer)，C60作為電子受體層(Acceptor layer)，BCP及BAlq作為電洞/激子阻隔層(Hole/Exciton block layer)。實驗結果發現，當ZnPc與C60之厚度分別為30nm、40nm，以及使用BCP作為隔離層時，以AM1.5 100mW/cm2之入射光照射時，開路電壓為0.466V，短路電流為1.80A/cm2，FF=0.42，轉換效率為0.35%，這是由於激子(Exciton)分別為ZnPc與C60中之擴散長度為30nm及40nm，使得激子能夠擴散到p-n接面，並分離為自由電荷，在各自傳輸到相對應電極，形成光電流。此外BCP能隙及最高填滿能階軌域(Highest Occupied Molecular Orbital, HOMO)較BAlq高，因此在阻擋激子及電洞的能力也就比較好。最後，加入一層I層之P-I-N結構時，能夠有效的增加短路電流。當其厚度為20nm時，以空氣質量1.5 100mW/cm2的入射光照射在P-I-N結構之太陽能電池(ITO/20 nm ZnPc/20 nm ZnPc:C60/30 nm C60/15nm BCP/100nm Al)上所量測出的VOC=0.481 V，JSC=2.67A/cm2，FF=0.38，η=0.49 %。

關鍵字

有機太陽能電池；有機發光二極體；隔離層

並列摘要

There are two parts in this thesis.(1) In OLED:This study deposited SiO2 of various thickness by PECVD or coated photo-resistor of various thickness at the edge of patterned OLED anode and between the patterned anode and the organic layer as isolation-layer to improve the leakage-current of OLED. Leakage-current would cause the loss of carriers around the emitting zone, which adversely affects the recombination of electrons and holes in the emit- ting zone and results in poorer luminance efficiency. The study find that as SiO2 thickness increased, leakage-current was significantly reduced. When SiO2 thickness increased from 0 nm to 250 nm, the luminance efficiency of device rose from 1.7 cd/A to 3.4 cd/A at 150 mA/cm2. Lastly the study examined the effect of photo-resistor thickness on reducing the leakage- current and finds that at 2250 nm, the luminance efficiency was enhanced further to 4.5 cd/A at 150 mA/cm2.(2) In OSC: Utilize ZnPc and C60 as Donor layer and Acceptor layer in the OSC, respectively. BCP and BAlq as Hole/Exciton block layer. As a result, when the thickness of ZnPc and C60 are 30 nm and 40nm respectively, and utilize BCP as block layer, under solar simulated light irradiation(AM1.5 100mW/cm2), the open-circuit voltage and short- circuit current are 0.466 V and 1.80 mA/cm2 respectively, FF=0.42, and power conversion efficiency is 0.35%. Because of the diffusion lengths of exciton in ZnPc and C60 layers are 30 nm and 40 nm.In addition, energy gap and HOMO of BCP are higher than BAlq, therefore it has enough power to block Exciton and Hole. Final, inset a intrinsic layer(I-) can increase short-circuit current efficaciously. When the thickness of I-layer is 20 nm, under solar simulated light irradiation(AM1.5 100mW/cm2) ,the open-circuit voltage and short- circuit current are 0.481 V and 2.67 mA/cm2 respectively, FF=0.38, and power conversion efficiency is 0.49%.

並列關鍵字

isolation layer ； Organic solar cells ； OLED

參考文獻

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有機發光二極體及太陽能電池之研製

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