Electrical performance of monolayer MoS₂ field-effect transistors prepared by chemical vapor deposition

Molybdenum disulfide (MoS₂) field effect transistors (FET) were fabricated on atomically smooth large-area single layers grown by chemical vapor deposition. The layer qualities and physical properties were characterized using high-resolution Raman and photoluminescence spectroscopy, scanning electron microscopy, and atomic force microscopy. Electronic performance of the FET devices was measured using field effect mobility measurements as a function of temperature. The back-gated devices had mobilities of 6.0 cm²/V s at 300 K without a high-κ dielectric overcoat and increased to 16.1 cm²/V s with a high-κ dielectric overcoat. In addition the devices show on/off ratios ranging from 10⁵ to 10⁹.