Edge Chemical Passivation Engineering of Armchair MoSi 2 N 4 Nanoribbon PMOS Field‐Effect Transistors: A First‐Principles DFT–NEGF Investigation

Edge chemical passivation provides an effective strategy for tuning the electronic and transport properties of two‐dimensional semiconductor nanoribbons. Here, the effects of hydrogen (H), chlorine (Cl), and fluorine (F) edge passivation on armchair MoSi 2 N 4 nanoribbon PMOS field‐effect transistors are systematically investigated using density functional theory combined with the nonequilibrium Green’s function (DFT–NEGF) approach. The electronic band structure, density of states (DOS), transmission spectrum, transfer characteristics, and transconductance are analyzed to elucidate the impact of edge termination. All passivation configurations improve the electronic and transport characteristics relative to the pristine nanoribbon. The electronic bandgap increases from 1.80 eV for the pristine structure to 1.88, 1.95, and 2.03 eV for H‐, Cl‐, and F‐passivated structures, respectively, while the DOS gap increases from 1.16 to 1.34, 1.38, and 1.56 eV. These changes indicate effective suppression of localized edge states. Among the investigated configurations, F passivation yields the highest ON‐state current and I ON / I OFF ratio, while maintaining a comparable OFF‐state current. The enhanced performance is attributed to the high electronegativity of F, which promotes edge charge redistribution and carrier confinement.