Influence of donor-acceptor layer sequence on photoresponsive organic field-effect transistors based on palladium phthalocyanine and C60

摘要

Photoresponsive organic field-effect transistors (PhotOFETs) based on palladium phthalocyanine (PdPc) and C60 were fabricated with different donor-acceptor layer sequences. Both planar heterojunction devices fabricated exhibit better performance under illumination than the single PdPc device. PhotOFETs with the structure SiO_2/C60/PdPc/Au exhibit a higher photosensitivity and photoresponsivity than that with the structure SiO_2/PdPc/C60/Au. The origin for this is largely the high mobility of C60 and the well-matched LUMO levels of PdPc and C60. The maximum photosensitivity of the SiO_2/C60/PdPc/Au device is 8 × 10~3, and, the photoresponsivity is approximately 28 times that of the single component PdPc device.