Broadband and Persistent Photoconductivity Immune Phototransistors Achieved by a Perovskite/IGZO Heterojunction

Due to the wide band gap (>3 eV) of indium gallium zinc oxide (IGZO), an IGZO transistor hardly absorbs visible and near-infrared (NIR) photons. We have successfully developed a high-performance phototransistor based on the perovskite (PVK) and IGZO heterojunction. By employing a narrow band gap (1.68 eV) of the PVK layer, the PVK/IGZO phototransistor demonstrates excellent light detection in the 365–820 nm range and eliminates the undesired persistent photoconductivity (PPC) effect. Under green light of 520 nm, the device achieves an impressive photoresponsivity of 1.08 A·W–1 and a detectivity of 4.70 × 1011 Jones, positioning it among the best reported values. In particular, under NIR light of 820 nm, the device achieves a photoresponsivity of 0.07 A·W–1 and a detectivity of 4.53 × 1010 Jones, ranking the highest among similar structures. The PVK/IGZO phototransistor displays a fast rise/decay time in the range of hundreds of milliseconds or less. This work offers a cost-effective solution for developing high-performance next-generation photodetector devices tailored to artificial intelligence applications.