초록 |
Small Molecular Near-Infrared Photodetectors (SMNIP) having a donor and acceptor system should efficiently transport carriers to the electrodes. However, leakage current due to transported carriers in the opposite direction and low hole mobility of a donor reduce detectivity. In this work, we investigated the effect of buffer layer between Lead phthalocyanine (PbPc) for a donor having absorption of near-infrared and ITO. The buffer layer such as Zinc phthalocyanine (ZnPc) and 4,4′,4″-tris(n-(2-naphthyl)-n-phenyl-amino)-triphenylamine (2TNATA) having lower HOMO level and higher hole mobility than donor shows higher detectivity due to efficient hole extraction and blocking oppositely transported electrons compared to N,N′-diphenyl-N,N′-bis(1-naphthyl)(1,1′-biphenyl)-4,4′diamine (NPB), 4,4′,4″-tris(n-(2-naphthyl)-n-phenyl-amino)-triphenylamine (2TNATA) although they have higher hole mobility than a donor. |