Self-Powered Photodetectors Based on Scalable MOCVD-Grown WS2–MoS2 Heterostructures

Self-powered photodetectors operate without external power sources and are therefore of interest for wireless light sensing applications in different environments. To ensure high values of both linear dynamic range and bandwidth, optically generated charge carriers must be separated and extracted efficiently even in the absence of an external bias, and charge carrier transport effects that limit performance data in bulk semiconductor devices must be minimized. Here, we present a self-powered photodetector device for the visible spectral range, where an ultrathin MOCVD-grown MoS₂–WS₂ heterostructure with type-II band alignment is embedded into a p–n architecture to enforce efficient separation and extraction of optically generated electron–hole pairs. Our scalable, 6 mm²-sized photodetector prototype exhibits a linear dynamic range of at least 110 dB and a record high bandwidth with a cutoff frequency beyond f_c = 80 MHz.