Nearly Ideal Subthreshold Swing in Monolayer MoS₂ Top-Gate nFETs with Scaled EOT of 1 nm

Transistor scaling enabled by gate length scaling requires EOT scaling to less than 1 nm thickness [1]. This work successfully integrates Hf-based ALD higher-k dielectrics with CVD-grown monolayer (1L) MoS 2 to build top-gate nFET with EOT ~1 nm with nearly ideal subthreshold swing of 68 mV/dec. The gate stack described here achieves a high $\varepsilon_{\mathrm{e}\mathrm{f}\mathrm{f}}$ ~13.53, a large $\mathrm{E}_{\mathrm{B}\mathrm{D}}$ ~12.4MV/cm, and excellent leakage current density. This is a remarkable performance among reported gate dielectrics on the transition metal dichalcogenides (TMDs) on which it is notoriously difficult to deposit a pinhole-free dielectric.