Bridging Synthesis and Controllable Doping of Monolayer 4 in. Length Transition-Metal Dichalcogenides Single Crystals with High Electron Mobility

Epitaxial growth and controllable doping of wafer-scale atomically thin semiconductor single crystals are two central tasks to tackle the scaling challenge of transistors. Despite considerable efforts are devoted, addressing such crucial issues simultaneously under 2D confinement is yet to be realized. Here, an ingenious strategy to synthesize record-breaking 4 in. length Fe-doped transition-metal dichalcogenides (TMDCs) single crystals on industry-compatible c-plane sapphire without special miscut angle is designed. Atomically thin transistors with high electron mobility (approximate to 146 cm(2) V-1 s(-1)) and remarkable on/off current ratio (approximate to 10(9)) are fabricated based on 4 in. length Fe-MoS2 single crystals, due to the ultralow contact resistance (approximate to 489 omega mu m). In-depth characterizations and theoretical calculations reveal that the introduction of Fe significantly decreases the formation energy of parallel steps on sapphire surfaces and contributes to the edge-nucleation of unidirectional alignment TMDCs domains (>99%). This work represents a substantial leap in terms of bridging synthesis and doping of wafer-scale 2D semiconductor single crystals, which should promote the further device downscaling and extension of Moore's law.

Automated summary

This study presents an ingenious strategy for the synthesis of 4 inch long Fe-doped transition-metal dichalcogenides (TMDCs) single crystals on industry-compatible c-plane sapphire without special miscut angle. The fabricated atomically thin transistors based on these single crystals exhibit high electron mobility (approximately 146 cm(2) V-1 s(-1)) and remarkable on/off current ratio (approximately 10(9)) due to the ultralow contact resistance (approximately 489 Ωμm). This work represents a significant advancement in the synthesis and doping of wafer-scale 2D semiconductor single crystals.