Organic Light Detectors: Photodiodes and Phototransistors

Abstract

While organic electronics is mostly dominated by light-emitting diodes, photovoltaic cells and transistors, optoelectronics properties peculiar to organic semiconductors make them interesting candidates for the development of innovative and disruptive applications also in the field of light signal detection. In fact, organic-based photoactive media combine effective light absorption in the region of the spectrum from ultraviolet to near-infrared with good photogeneration yield and low-temperature processability over large areas and on virtually every substrate, which might enable innovative optoelectronic systems to be targeted for instance in the field of imaging, optical communications or biomedical sensing. In this review, after a brief resume of photogeneration basics and of devices operation mechanisms, we offer a broad overview of recent progress in the field, focusing on photodiodes and phototransistors. As to the former device category, very interesting values for figures of merit such as photoconversion efficiency, speed and minimum detectable signal level have been attained, and even though the simultaneous optimization of all these relevant parameters is demonstrated in a limited number of papers, real applications are within reach for this technology, as it is testified by the increasing number of realizations going beyond the single-device level and tackling more complex optoelectronic systems. As to phototransistors, a more recent subject of study in the framework of organic electronics, despite a broad distribution in the reported performances, best photoresponsivities outperform amorphous silicon-based devices. This suggests that organic phototransistors have a large potential to be used in a variety of optoelectronic peculiar applications, such as a photo-sensor, opto-isolator, image sensor, optically controlled phase shifter, and opto-electronic switch and memory.

Photosensitive and Flexible Organic Field‐Effect Transistors Based on Interface Trapping Effect and Their Application in 2D Imaging Array

“…OPTs are an attractive category of OFETs, which can be used as photodetectors, light‐induced switches, light‐triggered amplifiers, and image sensors, amongst other applications 15, 16, 17, 18, 19, 20, 21, 22, 23. In most studies on OPTs, it was the organic semiconductor itself, which exhibited photosensitivity.…”

Progress in organic-inorganic hybrid halide perovskite single crystal: growth techniques and applications

“…Currently, perovskite thin films have been under intensive investigation and most reported applications have focused on polycrystalline thin films. Accordingly, a lot of recent reviews regarding the progress in perovskites concentrate on their polycrystalline film form [20][21][22][23][24][25][26][27][28][29][30][31][32][33][34][35]. Although the study of perovskite single crystals is just in its early stage, it is highly desirable to investigate fundamentally intrinsic properties of perovskites due to their low trap density and absence of grain boundaries.…”

High performance organic ultraviolet photodetector with efficient electroluminescence realized by a thermally activated delayed fluorescence emitter

“…[10][11][12][13][14][15] Especially, photodetection in UV region is of great interest in solar astronomy, missile plume detection, environmental monitoring, and so on. 16 Recently, organic integrated devices with UV photodetective and electroluminescent (EL) properties were realized via intramolecular 17 and intermolecular charge transfer architectures. 18,19 This kind of devices can realize two functions of UV detection and light emission in a single configuration, which can be widely applied to portable and wearable electronic products.…”