Etching of graphite and diamond by thermal energy hydrogen atoms

Theoretical Studies on Formation, Property Tuning and Adsorption of Graphene Segments

“…As illustrated in Figure 1(a), the HOMO-LUMO difference of H/sp 2 -carbon is significantly different from that of H/sp 3 -carbon, indicating that the reactivity of atomic hydrogen with the two carbon phases should be considerably different. The smaller HOMO-7 LUMO difference of H/sp 2 -carbon implies the preferential etching selectivity for the sp 2 phase, which is in good agreement with experiments (Donnelly, McCullough et al 1997;Ishikawa, Yoshimi et al 1997). Fig.…”

Hyperthermal atomic hydrogen and oxygen etching of vertically oriented graphene sheets

“…[8][9][10] The atomic hydrogen ions, neutrals, and excited neutrals impinging on the CNS etch the carbon surfaces by the creation and subsequent desorption of CH 4 . [11][12][13][14][15][16][17][18][19][20][21][22][23][24][25][26][27][28][29] Further, we observed substantial fluxes of CO and CO 2 ͑greater than CH 4 ͒, suggesting a similar type of cathode etching by ESD-generated oxygen from the surface copper oxide. In this article, we demonstrate that in ultrahigh vacuum ͑UHV͒ field emission testing of CNS films, ESD-generated products etch the outboard graphene edges at moderate currents and simultaneously increase the defect density.…”

Mechanism and model of atomic hydrogen cleaning for different types of carbon contamination on extreme ultraviolet multilayers

“…As conservation of the amount of hydrogen is required, the equilibrium equation between incident hydrogen and hydrogen desorption is written as [15]:…”

“…As for the process of the chemical reaction, the active atomic hydrogen combines with atomic carbon by a chemical reaction, first producing volatile hydrocarbon, which later escapes to the surrounding atmosphere [15,[18][19]. The cleaning rate is described by the change of carbon thickness, and it is described in the model as:…”