Synergetic engineered all van der Waals photodetectors for robust photodetection

Atomically thin heterojunctions represent a crucial area of research in the context of post-Moore era optoelectronics. Ongoing investigations into layered van der Waals (vdW) heterojunctions have focused on their potential for photodetection, with the thickness of the constituent layers serving as a variable that can be optimized to enhance the efficiency of photosensors. This article examines the significance of synergetic engineered all-van der Waals photodetectors, which demonstrate high linearity and a substantial linear dynamic range, alongside ultralow dark currents, all achieved through a singular junction. We emphasize the critical role of thickness-engineered layers in establishing a robust depletion region and in modulating the Schottky barrier height via vdW contacts. This synergistic adjustment is essential for improving the key figures of merit (FoMs) of photosensors. Our findings indicate that a meticulous engineering approach is paramount in the design of vdW-based photodiodes. Specifically, it is vital to optimize the thickness of the layers in conjunction with the integration method of the contacts. This optimization aims to strike a favorable balance among photo carrier generation-recombination, transport, and extraction, ultimately facilitating a highly sensitive broadband photo response.