An n-type Schottky contact with low tunneling resistance in a 2D FeB2/SiC heterostructure.

The design of low-resistance metal-semiconductor contacts remains a critical challenge for the development of high-performance two-dimensional (2D) electronic devices. In this work, we design and systematically investigate the structural stability, electronic properties, and interfacial contact characteristics of a 2D FeB2/SiC metal-semiconductor heterostructure using first-principles calculations. The FeB2/SiC heterostructure is found to be energetically stable with weak van der Waals (vdW) interlayer interaction, thereby preserving the intrinsic electronic properties of the individual monolayers. Owing to the larger work function of FeB2 compared to that of SiC, charge transfer occurs from the SiC layer to the FeB2 layer, resulting in interfacial charge redistribution and downward band bending in the SiC layer. Consequently, an n-type Schottky contact is formed at the interface with a Schottky barrier height of about 0.70 eV. Projected density-of-states analysis indicates negligible metal-induced gap states (MIGS) at the interface, implying weak Fermi-level pinning. Moreover, the FeB2/SiC heterostructure exhibits a low tunneling resistance of 1.40 × 10-9 Ω cm2, confirming the formation of a low-resistance contact. These results demonstrate that the FeB2/SiC heterostructure is a promising two-dimensional metal-semiconductor contact for high-performance and low-power electronic devices.