Integrating top-gated high dielectric constant material on 2D semiconductor with good scalability possesses high importance while a huge gap includes material selection and integration method prohibits further development. Herein, the thermal evaporation-based deposition of Er₂O₃ is demonstrated as a promising dielectric material that can be integrated directly on top of MoS₂ with superior scalability. An EOT less than 1 nm dual gate MoS₂ FET is demonstrated with dielectric physical thickness 3.5-nm and can be operated within 1 V, highlighted as a new alternative applicable for future scaling