A differential photodetector: Detecting light modulations using transient photocurrents

Inserting an insulating layer (I) into a conventional metal-semiconductor-metal (MSM) photodiode converts the DC photoresponse into a strong transient signal, highly applicable to modulated signal photodetection. In this study, we demonstrate the intrinsic benefits of organic MISM photodetectors, namely their effective operation under high steady-state lighting, responding only to changes in light intensity, and their ability to react to several light sources simultaneously. Furthermore, the strong interaction at the S/I interface, specific to this architecture, significantly enhances the device photoresponse, resulting in highly efficient differential photodetection, compared to a composite MSM + C device fabricated from identical elements.