| 초록 |
Here we tried to optimize organic photodiodes(OPDs) by systematic approach in terms of hole blocking layer, electron blocking layer, thickness and morphology of active layer. As a p-type semiconductor, we selected PBDTT-DPP which has a backbone consisting of repeating alkylthienylbenzodithiophene (BDTT) and diketopyrrolopyrrole (DPP) units. PBDTT-DPP is known to be a promising p-type material for organic photovoltaic(OPV) application. Considering its high optoelectronic properties, we tried to fabricate high performance OPDs in conjunction with PC70BM as an n-type semiconductor. It was turned out that the thickness of the active layer and the energy level of blocking layers is critical to minimize the dark current of OPDs, enabled by systematic investigation of various interfacial layers. We have also found that the morphology of the active layer is directly related with the photocurrent of OPDs by changing the deposition method of PBDTT-DPP/PC70BM blend or by using post-treatment. |
