A modified wrinkle-free MoS 2 film transfer method for large area high mobility field-effect transistor

Wrinkle-free transfer of chemical vapor deposition (CVD) synthesized 2D MoS 2 is a prerequisite for large-area high-performance device fabrication. The surface-energy-assisted transfer method is a suitable method for MoS 2 transfer, which greatly reduces the damage to the MoS 2 . However, in the process of tiling the MoS 2 to the new substrate, droplets are sandwiched between the MoS 2 and substrate, which are difficult to remove and easily cause wrinkles and cracks. To avoid the realization of wrinkles and cracks in the transfer, we developed a modified surface-energy-assisted transfer method that modifies the spreading parameter S of residual droplets sandwiched between the MoS 2 and substrate. By using this strategy, the liquids were easily to remove from the MoS 2 /substrate interface resulting in a smooth MoS 2 film with no wrinkles. Larger area back-gated field-effect transistor (FET) arrays were also fabricated based on the transferred monolayer MoS 2 (10 × 10 mm) with atomic layer deposition prepared HfO 2 as the high-k gate insulator. The FETs exhibited a high on/off ratio of 10 8 and carrier mobility up to 118 cm 2 V −1 s −1 , which is the highest mobility values reported for back-gate transistors fabricated with CVD synthesized MoS 2 . This transfer method provides a useful strategy for the fabrication of larger area high property FETs on MoS 2 .