Highly Durable Organic Photodetector for Complementary Metal Oxide Semiconductor Image Sensors
Journal
Organic Electronics
Date
2021.03.30
Abstract
In the recent past, it has been practically impossible to utilize organic electronics compatible with conventional semiconductor fabrication processes because of their weak chemical resistivity and environmental durability. Employing organic electronics into various industrial processes has been difficult. In order to preserve their intrinsic functionality of organic materials, only few fabrication processes could be allowed. Organic devices had chronic limitations with regard to size reduction and circuit integration. However, it is prerequisite to secure process-expandability and silicon-process compatibility toward to high-resolution electronics with mass-production system. In this study, we have developed a wet-process compatible organic photodetectors, by replacement of conventional shadow-mask process into photolithographic process; leading to the suppression of particles during the serial fabrication processes, with high operational stability. Green organic photodiodes exhibit lower dark current (1.0ⅹ10-11 A/cm2) with the high photon-electron conversion efficiency (EQE=65％). Charge collection and charge separation efficiencies were kept stable; (？cc = 84.6％, ？cs = 97.7％) further, the photo-response property (？rise,99.9％) was maintained at a value less than 1 msec. Moreover, organic semiconductors have been proved that it is compatible with conventional wet and the dry-etching processes due to thin film encapsulation layers. Finally, a novel organic image sensors could withstand 500 hours under 85℃/85 humidity condition and 1000 thermal cycles (-55 ~ 125℃). Because of its robustness and strong barrier properties, we expect that the novel process architecture reported herein can be extended to any organic electronic device including the widely commercialized organic light emitting diodes or organic photovoltaic devices.