Pulsed laser deposition of the protective and Anti-reflective DLC film

Protective and anti-reflective DLC film with double-layer structure was designed and prepared on the easycorrosive silicon. The inner oxygen-doped DLC layer deposited in oxygen atmosphere by femto-second laser had high transmittance, while the outer pure DLC layer grown in high vacuum by nano-second laser had high hardness and corrosion resistance. The atomic bonds and microscopic structures of the pure and oxygen-doped DLC layers showed the inherent reason for the huge difference in their optical and mechanical properties. Tests showed that when the thickness of outer pure DLC layer reduced, the optical transmission of the double-layer DLC film could increase, however, the nano-hardness for the protective effect would decrease. Corrosion test demonstrated the pure DLC layer had good corrosion resistance against the alkaline solution, but it must be thick enough to prevent the alkaline solution effectively from soaking into the deep-seated depth to corrupt the inner oxygen-doped DLC layer.

Automated summary

A double-layer DLC film was designed and prepared on corrosive silicon with different oxygen-doped and pure DLC layers to achieve high corrosion resistance and optical transmission. The pure DLC layer showed good resistance to alkaline solution, but the thickness should be considered to prevent solution penetration into the inner layer effectively.