Back‐Gated MoS ₂ Field Effect Transistors as Probes for Melamine‐Induced Surface Charge Transfer Doping

Abstract In this study, we report on the customization of multilayer MoS 2 ‐FET transfer properties by melamine via surface charge doping. NMP was used as a solvent to create the melamine solution. After melamine doping, the multilayer MoS 2 ’s charge carrier density was roughly doubled. After melamine doping, mobility was calculated to be around 28.57 cm −2 V −1 s −1 , whereas the pristine's mobility was approximately 27.38 cm −2 V −1 s −1 . The subthreshold swing of the doped device was ∼ 0.94 V/decade, which is less than the pristine device's ∼ 1.6 V/decade. The doped device demonstrated outstanding switching properties. A factor of greater than 7 was seen in the reduction of extracted contact resistance. The melamine molecule forces n‐doping on the multilayer MoS 2 , as seen by the left shift of the threshold voltage following the doping process. Following the doping procedure, the Raman spectrum's downward trending E 2g and A 1g peaks shows that the n‐type doping system's electron concentration is rising. Melamine functions as an n‐type dopant, as confirmed by XPS evidence. Melamine is confirmed to be present on the MoS 2 surface by TOF‐SIMS and AFM measurements. Chemical doping might be a useful technique for improving the layered materials' electrical characteristics.