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

Abstract

By incorporating organic BHJ onto graphene, graphene/ZnO/PTB7-Th:IEICO-4F shows gate tunable photodetection/photostorage switching features for the implementation of both retinomorphic vision and memorial preprocessing functions.

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 × 10 ⁶ A W ⁻¹ at 895 nm, corresponding to a detectivity of 4.8 × 10 ¹² Jones. Importantly, the rewritable and switching infrared optoelectronic memory function can be achieved with good retention over 10 ⁴ 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.