Atomic Layer Epitaxial 2D Dielectric $h$-Aln as Interfacial Layer With Excellent Leakage and Eot $lt;1 ~\text{nm}$ for TMD-FETs

This study demonstrates the fabrication of an ultrathin epitaxial hexagonal aluminum nitride ($h$-AIN) interfacial layer (IL) via atomic layer deposition (ALD) to enable high-quality gate dielectrics on monolayer tungsten disulfide ($\text{WS}_{2}$). The optimized $h$-Al and hafnium oxide $\left(\text{HfO}_{2}\right)$ stack achieves an equivalent oxide thickness $(\text{EOT})<1$ nm, ultra-low leakage currents $\left(10^{-2} ~\mathrm{A} / \text{cm}^{2}\right)$, and exceptional transistor performance, including low subthreshold swing, minimal hysteresis, and high on-off ratios ($\sim 10^{6}$). This CMOS-compatible, lowtemperature process offers scalable, uniform coverage for advanced low-power electronics.