镀铝衍射光栅表面有机污染物的等离子体清洗技术

Organic contaminants adsorbed by diffraction gratings in high-energy laser devices devices are one of the key factors leading to diffraction grating damage. Plasma cleaning technology can achieve online removal of diffraction grating surface pollutants. The plasma cleaning range is analyzed by the finite element method, and the law that the plasma cleaning radius increased with the decrease of the cleaning distance is obtained. The relationship between the plasma cleaning process parameters and the removal effect of surface organic pollutants is studied. The results show that with the increase of the cleaning distance and the oxygen content in the process gas, the polar part and the dispersion part of the surface free energy of the aluminized diffraction grating increases. The increase of the polar part plays a leading role. The surface of the aluminized diffraction grating after plasma cleaning exhibits a clean periodic sawtooth structure, and the C1s (285.0 eV) peak decreases from 6.65×10⁴ to 2.86×10⁴. The changes of surface free energy after plasma cleaning of aluminized diffraction gratings are studied, and the results show that the polar groups on the surface of aluminized diffraction gratings will adsorb hydrocarbons in the air, resulting in the aging phenomenon of decreased surface free energy. The research results provide a new approach for the on-line plasma removal of organic contaminants on the surface of aluminized diffraction gratings.