Esaki Diodes based on MoS₂/p-Si Heterostructures

Recently, two-dimensional (2D) materials have been intensively studied for next-generation ultrathin and flexible electronic and optoelectronic devices. Compared with one-dimensional (1D) nanostructures, 2D materials are more suitable for 3D monolithic integration and more compatible with traditional CMOS microfabrication. In this work, we demonstrate Esaki diodes based on MoS₂/p-Si heterostructures for the first time. Large-scale and high-quality molybdenum disulfide (MoS₂) was grown on a highly doped silicon substrate in a chemical vapor deposition (CVD) system. The domain size of monolayer MoS₂ is about 50 µm. Raman and AFM further confirmed that the synthesized MoS₂ is monolayer. The electrical properties of MoS₂/p-Si heterostructures were also systematically investigated by conductive AFM. Interestingly, the IV curve exhibits prominent negative differential resistance (NDR) effect at room temperature. This NDR effect is due to the band-to-band tunneling in the MoS₂ and highly doped p-Si heterostructures. This work provides the experimental groundworks for Esaki diodes based on TMDC/Si heterostructures and opens up new opportunities for novel devices based on 2D materials and 3D semiconductors.