本論文中，我們探討有機太陽能電池之主動層濃度與退火機制，並結合有機寬能隙材料於有機太陽能電池中。由於有機太陽能電池的主動層濃度會因為熱退火的溫度不同，進而產生不同的表面型態而影響元件，因此探討主動層濃度對應於不同熱退火的溫度達到最佳的元件特性表現；並藉由有機材料對光的吸收特性，我們利用雷射照射結合熱退火的技術來提升有機高分子薄膜的排列；此外製作有機小分子太陽能電池，加入有機寬能隙薄膜於陽極與有機主動層之間。藉由摻雜有機寬能隙材料的特性應用於有機高分子太陽能電池元件，利用摻雜的方式加入於有機高分子主動層，可有效改善電洞傳輸，降低電子與電洞復合，改善元件特性
首先我們探討有機高分子材料：聚-3己烷塞吩與富勒烯衍生物之濃度對元件特性的影響，對於不同濃度(3、4、5 wt %)進行不同熱退火溫度的處理，從實驗結果得知，不同的主動層濃度其元件最佳的效率會對應到不同的退火溫度，濃度越高，其退火溫度也會隨之提升。在濃度4wt %的有機太陽能電池元件，經由130oC熱處理可獲得最佳的元件特性。
其次，利用雷射結合熱退火的製程應用於有機太陽能電池元件，由於有機材料聚-3己烷塞吩的吸收光譜範圍於綠光波段，因此利用波長532nm的綠光雷射，並結合前段最佳化的熱處理條件，用於主動層薄膜，藉此改善有機材料聚-3己烷塞吩的高分子鏈的排列與長度，並提升分子的結晶性，進而改善元件特性的表現。
第三，研製有機小分子太陽能電池之結構，藉由加入寛能隙電子阻擋層，藉以提升元件的光電流吸收效率，平衡載子收集於電極之效率增進短路電流，進而提升元件效率；嘗試使用三種寬能隙的電子阻擋層材料在最佳化的單異質接面太陽能電池的結構，材料分別為m-MTDATA、MeO-TPD、Ir(ppz)3，並調整各材料其最佳厚度，其結構為ITO/electron blocking layer/CuPc(30 nm)/C60(40 nm) /BCP(10 nm)/Al(100 nm)。其最佳厚度分別為m-MTDATA(4 nm)、MeO-TPD (3 nm)、Ir(ppz)3(0.5 nm)。
第四，利用摻雜有機寬能隙材料Tris(phenylpyrazole)iridium (Ir(ppz)3) 於主動層中，製作有機太陽能電池，藉由摻雜Ir(ppz)3可有效改善的電洞傳輸，使得電子與電洞傳輸平衡，進而提升短路電流，此外藉由摻雜此有機材料亦可增加主動層薄膜短波長的吸收強度；由實驗結果得知，摻雜1 mg的Ir(ppz)3可得到最好的元件效率，其元件特性之短路電流為11.8 mA/cm2、開路電壓為0.61 V、理想因子為0.59、功率元件轉換效率可達4.23 %；最後結合雷射熱退火技術與摻雜寬能隙材料之製程應用於有機太陽能電池，可以得到最佳的元件特性，其元件功率轉換效率可達4.54%。

In this dissertation, we studied the effect of organic solar cells active layer concentration and annealing treatment, and combined the organic wide-band-gap material. Due to different active layer concentrations and various annealing temperature would influence the surface morphology of active layers. We optimize the active layer concentration with different annealing temperature to achieve the best device performance. Furthermore, we use the 532nm laser combined with thermal annealing method to treat the polymer active layer for enhance polymer the crystallization. We also investigated the small molecular organic solar cell inserting a thin organic wide-band-gap layer between the anode and active layer to enhance the device performance. Moreover, we also try to dope the organic wide-band-gap material in the polymer active layer to enhance the hole transport and reduce the carrier recombination.
Firstly, we studied concentration of the polymer material: Poly (3-hexylthiophene) (P3HT): [6,6]-Phenyl-C61 butyric acid methyl ester (PCBM) of 3~5 wt% with various annealing temperature. For the optimized device performance, with higher concentration of active layer, the annealing temperature was higher. The best device performance was shown in concentration of 4 wt %, annealing temperature was 130 oC.
Secondly, we fabricated the polymer solar cells with laser and thermal annealing treatment. We used 532nm green laser as the laser annealing source because the maximum intensity of P3HT absorption spectrum is located at the range of green light. Combined laser and thermal annealing treatment can improve the P3HT polymer chains length and crystallization, also enhance the device performance.
Thirdly, we investigated the organic small molecular solar cell with using wide-band-gap electron-blocking layer, which can improve photocurrent absorption efficiency, balance carrier mobility between acceptor and donor can affect the carrier collection efficiency, and enhance the Jsc, Voc, and PCE. We choose three wide-band-gap materials as electron-blocking layer, including m-MTDATA, MeO-TPD, and Ir(ppz)3, and try to modulate the thickness of electron-blocking layer to optimize the best properties. The structure of OPV cell is ITO / electron-blocking layer / CuPc(30 nm) / C60 (40 nm)/ BCP(10nm) / Al(100nm). The optimal thickness is m-MTDATA (4 nm), MeO-TPD (3 nm), and Ir(ppz)3 (0.5 nm), respectively.
Fourthly, we doped the organic wide-bnad-gap material Tris(phenylpyrazole)iridium (Ir(ppz)3) in polymer active layer. By doping Ir(ppz)3 can enhance the hole transport and balance the electron and hole transport to enhance the current density of the device. Furthermore, the Ir(ppz)3 also enhance the absorption in the short wavelength. From the experiment result, doping 1mg Ir(ppz)3 showed the best device performance with Jsc is 11.8mA/cm2, Voc is 0.61V, FF is 0.60, PCE is 4.24%. Finally, we investigated the polymer solar cell device with doping 1mg Ir(ppz)3 and annealed by thermal & laser co-treatment, the device PCE is reach 4.54%.

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