The impact of SF<sub>6</sub> plasma on the properties of graphene oxide
The paper considers the effect of SF<sub>6</sub> plasma-chemical treatment on the processes of defect formation and the electrical properties of graphene oxide partially reduced by heat treatment. The fluorine content on the graphene oxide surface is shown to increase as a result of SF<sub>6</sub> plasma treatment, depending on the plasma power and the duration of the treatment. The measured electrical parameters testify increased resistance of graphene oxide films as a result of plasma treatment. The rate of resistance change depends on the thickness of the films and is minimal for thin structures (~10 nm). Further heating of graphene oxide decreases its resistance, but the content of surface fluorine changes insignificantly. Thin films (10-15 nm) exhibit the smallest change of their resistance as a result of annealing. The highest rate of resistance change is observed for non-fluorinated samples. The obtained data indicate that only several nanometers of near-surface layers are subject to SF<sub>6</sub> plasma fluorination. The results testify the possibility of using SF<sub>6</sub> plasma treatment as an effective tool for selective fluorination of graphene oxide surface layers and controlled modification of its properties without changing the bulk properties of the material.