Surface etching effects of amorphous C:H and CNx:H films formed by supermagnetron plasma for field emission use

Supermagnetron plasma was used to deposit amorphous hydrogenated carbon (a-C:H) and hydrogenated carbon nitride (a-CN_x:H) films for field-emission devices using i-C₄H₁₀/(H₂ or N₂). It was also used to improve the field-emission characteristics by surface etching using N₂/H₂ plasma. The best emission threshold electric field (E_TH) was 13 and 12 V/μm for devices using as-deposited a-C:H and as-deposited a-CN_x:H films, respectively, while they were remarkably improved to 11 and 8 V/μm by surface etching using N₂/H₂ (120/40 sccm) gas, though surface roughness was slightly increased by the surface etching. The hardness of as-deposited films was higher than 22 GPa.