The source electrode and drain electrode are prepared with inkjet printed active layer on the spin-coated transparent source electrode, obtaining a vertical phototransistor with high photoresponsivity of ~1 500 A/W and high detectivity of ~1.6×10¹⁴ Jones. By doping electron capture materials PCBM into the active layer, the recombination of photo-generated holes in the active layer decreases and the photo-generated current increases. Thus the photodetector performance is improved further. It is found that when the electron capture material doping is 5wt%, the performance of phototransistor is better. The photoresponsivity is boosted to about 6 000 A/W and the detectivity is up to 1.4×10¹⁵ Jones.