Kim, Soo-Kwan Park, Sungmin Son, Hae Jung Chung, Dae Sung 2024-01-19T21:32:39Z 2024-01-19T21:32:39Z 2021-09-04 2018-10-23 0024-9297 https://pubs.kist.re.kr/handle/201004/120777 We suggest a synthetic strategy to accelerate charge collection narrowing (CCN) of a polymer photodiode so that a well-defined color selectivity can be realized even with a thin film thickness, which is the most important requirement for commercial application of polymer photodiodes. A new polymer semiconductor POFPhDT2FBT is synthesized by copolymerizing a difluorobenzothiadiazole acceptor with a difluorinated donor moiety. A polymer photodiode with a structure of indium tin oxide/ZnO/POFPhDT2FBT:PC70BM bulk-heterojunction (BHJ) (550 nm)/MoO3/Ag exhibits a high peak detectivity of similar to 6 x 10(12) jones at 650 nm with a narrow full width at half-maximum <80 nm as well as a low noise equivalent power (4.83 x 10(-14) W Hz(-0.5)), implying that CCN is achieved. This result is valuable as usually a BHJ film with a thickness of 550 nm exhibits a detectivity spectrum similar in shape to the absorption spectrum. We attribute the origin of the thin-film CCN in the POFPhDT2FBT:PC70BM BHJ to a weakened intramolecular charge transfer between the donor and acceptor of POFPhDT2FBT, leading to near-isotropic molecular orientations with a short-range pi-pi ordering, as confirmed by grazing-incidence X-ray diffraction. In other words, in the case of POFPhDT2FBT, a substantial number of photogenerated charges can remain as space charge carriers, thus enabling the CCN without using a thickness larger than 1 mu m. This study shows the possibility of efficient realization of color selectivity of a polymer photodiode even at a film thickness of 550 nm of the active layer, which can contribute to the improvement of the integration of organic image sensors in the near future. English AMER CHEMICAL SOC PHOTOVOLTAIC CELLS SOLAR-CELLS PHOTODETECTORS STABILITY Synthetic Approach To Achieve a Thin-Film Red-Selective Polymer Photodiode: Difluorobenzothiadiazole-Based Donor-Acceptor Polymer with Enhanced Space Charge Carriers Article 10.1021/acs.macromol.8b01751 1 MACROMOLECULES, v.51, no.20, pp.8241 - 8247 MACROMOLECULES 51 20 8241 8247 scie scopus 000448753000033 2-s2.0-85055054103 Polymer Science Polymer Science Article PHOTOVOLTAIC CELLS SOLAR-CELLS PHOTODETECTORS STABILITY 고분자 전하 수송체 유기반도체