Dual-Channel Co-Regulated Organic Phototransistors for Ultrasensitive Near-Infrared Biomimetic Eyes.

Abstract

Advanced machine vision applications require imaging devices capable of accurately detecting more spectral information about the target object than existing devices can capture. High-performance near-infrared (NIR) biomimetic eyes are fundamental to enabling this advanced application. However, the general limitations of NIR organic photodetectors, including high noise, weak sensitivities, and poor mechanical flexibility, have directly hindered their translation to high-performance biomimetic eyes. Herein, an ultrasensitive hemispherical NIR phototransistor array is proposed based on a dual-channel co-regulated strategy and used it to realize a high-definition biomimetic eye. A sandwich structure (semiconductor-insulator-semiconductor) is utilized as the photosensitive layer of the phototransistor. The devices exhibit extraordinary photosensitivity (≈10⁸) and a specific detectivity rate (≈10¹³ Jones) under NIR illumination (0.14 mW cm^-2). The ultra-thin, substrate-less structural properties result in a device thickness of ≈720 nm. These benefits enable our system to produce high-quality imaging, like that of the retina, and demonstrate the feasibility of its application in smart biomimetic visualization.