Impact of Thermal Annealing on the Interaction Between Monolayer MoS2 and Au

Herein, the impact of thermal annealing on the interaction between monolayer MoS2 and Au using Raman spectroscopy is investigated. It is found that MoS2 has two main modes of interactions with the underlying Au being either weakly coupled or strongly coupled. The regions strongly coupled to Au are hybridized to Au, minimally strained, and electron doped. The weakly coupled regions are found to be slightly hole doped with tensile strain of 1.0%. The overall areal coverage of the strongly coupled regions is not increased by thermal annealing, and the variability in the degree of hybridization increases at annealing temperatures above 100 degrees C. The data also show that monolayer MoS2 starts to decouple from Au around 100 degrees C, becoming fully decoupled above 200-250 degrees C, suggesting that monolayer MoS2 produced by Au-assisted mechanical exfoliation may be more easily transferred off Au at elevated temperatures.