Simultaneous Purification and Doping Regulation of CVD‐Grown MoS ₂ via Acid Treatment for High‐Performance Devices

Molybdenum disulfide (MoS 2 ) synthesized via Chemical Vapor Deposition (CVD) holds great potential for next‐generation electronic and optoelectronic devices. However, its device performance and stability are often hindered by intrinsic impurities (e.g., sodium ion (Na + ), molybdenum oxide (MoO 3 )) and the unintentional doping introduced during fabrication. In this study, a simple yet efficient hydrochloric acid (HCl) treatment strategy is proposed to simultaneously address these issues. Spectroscopic analyses show that the HCl treatment effectively removes MoO 3 , Na + , and organic residues while also further reducing the intrinsic n‐type doping of MoS 2 and suppressing the additional n‐type doping introduced by the lift‐off process. Consequently, the performance of the fabricated MoS 2 top‐gate transistors is significantly improved, achieving on‐off ratios exceeding 10 7 and a minimum subthreshold swing of 0.176 V/dec. Inverters constructed from these transistors achieve a voltage gain of 90 at a supply voltage of 3 V. Notably, the enhanced performance remains stable for more than 8 weeks. This low‐cost and photolithography‐compatible HCl treatment provides a scalable and robust pathway toward high‐performance two‐dimensional semiconductor devices.