N- and p-type sub-10 nm high-performance transistors based on monolayer GeX2 (X = As, Sb)

Exploring silicon alternatives for channel material is crucial for next-generation integrated circuits, two-dimensional (2D) materials are the most promising candidates due to their capability to suppress short-channel effects. In this study, we conducted simulations on the structural and electronic properties of 2D GeX₂ (X = As, Sb), as well as the ballistic transport characteristics of sub-10 nm n- and p-type 2D GeX₂ field effect transistors (FETs) based on first principles. The key metrics in terms of on-state current (I_on), delay time, and power consumption of n-type GeAs₂ and p-type GeSb₂ FETs can satisfy the requirements of the International Technology Roadmap for Semiconductors for high-performance devices until the gate length (L_g) is shrunk to 5 nm. Specifically, the I_on of n-type GeAs₂ FET and p-type GeSb₂ FET reaches 2299 and 1480 μA/μm when L_g is 7 nm, surpassing InSe, MoS_2, and WSe₂ FETs. Our work highlights the potential of 2D GeX₂ in future nanoelectronics.