Significant Detectivity Enhancement of Broad Spectral Organic–Inorganic Hybrid Photodiodes by C(60) Film as Hole-Blocking Layer

As an important classification of photodetectors, broad spectral photodiodes are ubiquitous in the fields of industry and scientific research. Here, we reported a type of broad spectral organic–inorganic hybrid photodiodes (OIHPDs) based on planar-bulk heterojunction, which composed of 3,4,9,10-perylenetertracarboxylic dianhydride (PTCDA), copper phthalocyanine (CuPc) and fullerene (C(60)). In our research, the dark current of the OIHPD with 10 nm C(60) film (10 nm-C(60) OIHPD) was as low as 25.6 μA, which is about 63 times smaller than the dark current of the OIHPD without C(60) film (C(60)-free OIHPD). It is considered that the significantly enhanced performance of 10 nm-C(60) OIHPD is attributed to the introduction of the C(60) film, which act as hole-blocking layer to reduce the dark current. And through the schematic energy level model combined with experimental measurements, the reason for the dark current change was well explained. Furthermore, the specific detectivity of 10 nm-C(60) OIHPD was almost one order of magnitude larger than it of C(60)-free OIHPD, and a notable enhancement of over 10(11) cm Hz(1/2)/W was obtained due to the fiercely reduced dark current. These results provide insights on how to improve the performance of organic photodiodes.