Near-infrared heterojunction field modulated phototransistors with distinct photodetection/photostorage switching features for artificial visuals

Abstract

With the rising demand for recording, computing and image capture, advanced optoelectronic detection, storage and logic devices are highly pursued. Nevertheless, a multi-functional vision chip based on infrared detection and memory switching has never been demonstrated. Here, by utilizing the electronic extraction layer ZnO and a face-on orientation of the bulk heterojunction (BHJ), we exhibit broadband visible to near-infrared photo-response and photo-storage characters on a graphene phototransistor. Functions as photodetection and photo-storage can be switched with the variation of the gate voltage. The device demonstrates high photo-responsivity up to 1.88 × 10⁶ A W⁻¹ at 895 nm, corresponding to a detectivity of 4.8 × 10¹² Jones. Importantly, the rewritable and switching infrared optoelectronic memory function can be achieved with good retention over 10⁴ s. Both retinomorphic vision and memorial preprocessing in artificial visuals are simultaneously realized by the photodetection/photostorage switching property. Such nearly all-solution processes in our phototransistors may open up the path for the large-scale and easy manufacturing of infrared multifunctional bio-optoelectronic devices.