Noninvasive van der Waals Interface Integrations for Intrinsic 2D Semiconductor Characterization.

Abstract

"Plug-and-probe" van der Waals (vdW) integration preserves surfaces of low-dimensional semiconductors but suffers from interfacial charge transfer and weak electrostatic control at the dielectric-channel heterointerface, underestimating intrinsic optical and electrical properties. We introduce a MoS₂-assisted noninvasive vdW integration method, achieving 94% intrinsic property expression. Controlled defect engineering on MoS₂ creates sulfur vacancies and dangling bonds, enabling uniform atomic layer deposition (ALD) of high-κ HfO₂ dielectrics. This resolves interfacial charge issues from conventional metal oxidation. Simultaneously, the ALD dielectric adsorbs onto source/drain contacts, eliminating the inner spacer in prior half-gate "plug-and-probe" structures. The fabricated monolayer MoS₂ transistor arrays demonstrate exceptional performance with on-state current densities exceeding 10^-6 A μm^-1, a subthreshold swing of 79 mV decade^-1, and an on/off current ratio of more than 10⁸, surpassing those of all reported "plug-and-probe" devices. The transistors maintain >90% initial performance after 200 °C annealing and ambient storage for 60 days, confirming their exceptional thermal and temporal stability.