Orientation-engineered PtTe₂ Schottky FETs: Quantum transport insights for dopant-free advanced technology nodes

As transistor scaling pushes beyond the 5 nm node, conventional silicon-based field effect transistors (FETs) face critical challenges including short-channel effects, high contact resistance, and power dissipation. This work presents a comprehensive quantum transport simulation study of monomaterial Schottky-junction FETs based on monolayer PtTe₂, leveraging its unique thickness-dependent electronic properties – where the semimetallic bilayer serves as the source/drain and the semiconducting monolayer forms the channel. First-principles simulations reveal that the device architecture enables efficient, doping-free carrier injection, sharp electrostatic switching, and directional performance tunability. The results show that transport along the Γ–M orientation achieves superior ON-state current, subthreshold swing (as low as 75 mV/dec), and suppressed OFF-state current, with OFF-currents and subthreshold swings comparable to IRDS-style low-power projections for sub-10 nm logic nodes. Projected local density of states (PLDoS) and energy-resolved current spectra further reveal distinct transport regimes and efficient Schottky barrier modulation. Compared to contemporary 2D-channel transistors, the monomaterial PtTe₂ Schottky FET offers a balanced trade-off between scalability, simplicity, carrier injection, and low-power operation. These findings highlight monolayer PtTe₂ as a promising candidate for ultra-scaled logic applications and demonstrate the strategic advantages of monomaterial, orientation-engineered architectures for beyond-CMOS nanoelectronics.