Synthetic Lateral Metal-Semiconductor Heterostructures of Transition Metal Disulfides.

Lateral heterostructures with planar integrity form the basis of two-dimensional (2D) electronics and optoelectronics. Here we report that, through a two-step chemical vapor deposition (CVD) process, high-quality lateral heterostructures can be constructed between metallic and semiconducting transition metal disulfide (TMD) layers. Instead of edge epitaxy, polycrystalline monolayer MoS in such junctions was revealed to nucleate from the vertices of multilayered VS crystals, creating one-dimensional junctions with ultralow contact resistance (0.5 kΩ·μm). This lateral contact contributes to 6-fold improved field-effect mobility for monolayer MoS, compared to the conventional on-top nickel contacts. The all-CVD strategy presented here hence opens up a new avenue for all-2D-based synthetic electronics.