Modeling and Improvement of Single-Layer MoS ₂ /Multilayer MoS ₂ Field Effect Transistor Photodetectors

The single-layer MoS2 and multilayer MoS2 field- effect transistor photodetector models were simulated and analyzed by ATLAS device simulator of Silvaco. The spectral response, responsivity and transfer characteristics of the two field-effect transistor photodetector models were analyzed, respectively. We show that the photocurrent generated by a single-layer MoS2 phototransistor depends solely on the illumination optical power at constant drain or gate voltage. And it shows good stability and photoresponse characteristics. In contrast, the modeled multilayer MoS2 phototransistor exhibits better photovoltaic performance than the single-layer MoS2 phototransistor, including wider spectral response and higher responsivity. These simulation results are basically consistent with the previous experimental data. These works are of great significance for the design and development of transition metal dichalcogenide-based advanced photodetectors.