Contact-Lifted Thickness-Modulated MoS₂ Diodes for Gate-Controlled Electronic Applications

Two-dimensional (2D) materials are promising materials for next-generation electronic devices because they have remarkable properties including a sizable electronic bandgap, relatively high carrier mobility, mechanical flexibility, and tunable electronic structure. The atomically thin profile of 2D materials also facilitates the formation of a thickness-modulated heterojunction between a few-layer region and a many-layer region without requiring process steps for n-type and p-type doping. Here, we show for the first time that thickness-modulated MoS2 diodes have a wide range of tunable forward voltages (1.5–4.5 V) and a large reverse breakdown voltage exceeding 10 V. The wide voltage tunability of the diodes is further demonstrated and verified by incorporating them into a voltage regulator and voltage clipper both having a tunable voltage range of ∼2 V. The regulator achieved attenuation of input voltage ripple by at least 1 order of magnitude. These results demonstrate the versatility of 2D materials for a variety of potential applications through band structure engineering via thickness modulation, mechanical strain, and gate electric fields.