Improved Electrical Performance of CVD Monolayer-MoS₂ TFT Via Wet Transfer of Van Der Waals Source/Drain Electrodes

In this study, we introduce a novel wet transfer method utilizing PMMA as a supporting tool for electrode transfer, with HF employed to facilitate the separation of the electrode from a sacrificial layer. This method is applied to fabricate source/drain electrodes for MoS 2 FETs. The implementation of the transferred Ag source/drain electrodes significantly enhances the carrier mobility of the CVD monolayer-MoS 2 FET by forming a Van der Waals contact between the monolayer MoS 2 and the Ag electrode, which ensures minimal contact resistance between them. As a result, compared with its counterpart with Ag source/drain electrodes prepared by thermal evaporation, the field-effect mobility of the proposed MoS 2 FET is increased from 25.3 cm²V⁻¹s⁻¹ to 69.1 cm²V⁻¹s⁻¹, while the contact resistance is reduced from 13.7 kΩ·μm to 1.49 kΩ·μm.