Sub-5 nm one-dimensional post-transition-metal monochalcogenide gate-all-around MOSFETs

Gate-all-around (GAA) metal-oxide-semiconductor field-effect transistors (MOSFETs) have emerged as promising candidates for continued device scaling owing to their superior electrostatic control. Here we perform a systematic first-principles quantum-transport investigation of post-transition-metal monochalcogenide (PTMC) nanowire GAA-MOSFETs, focusing on p-type InTe and GaTe. Compared with conventional Si-based nanowire counterparts, the proposed p-type devices achieve an exceptional balance between high drive current and low switching energy at aggressively scaled gate lengths, even outperforming the n-type SiX₂ (X = S, Se) counterparts. At L_g = 5 nm, the InTe and GaTe GAA-MOSFETs realize extremely high on-state currents of 2470 μA μm^-1 for high-performance (HP) and 1125 μA μm^-1 for low-power (LP) applications, while maintaining subthreshold swings (SS) below 60 mV dec^-1, surpassing the Boltzmann limit. The delay time (τ) and power-delay product (PDP) lie well below the 2028 International Technology Roadmap for Semiconductors (ITRS) targets, indicating ultrafast and energy-efficient operation. Notably, these devices satisfy the 2028 ITRS HP and LP standards even at gate lengths down to L_g = 2 nm and 3 nm, respectively. These findings establish InTe and GaTe nanowires as highly promising p-type channel materials for sub-5 nm, ultralow-power, high-performance CMOS technologies in the post-silicon era.