A new type of laser processing called “laser shock cleaning” in which the removal of the small particles is carried out by shock waves produced by laser sparking in air, is reported. The removal of very small metal particles (less than 1 μm in diameter) from silicon wafer surfaces was demonstrated successfully by this new technique. The process can be understood by investigation of the ablation phenomena and its cleaning mechanism can also be described by considering both the adhesion force of a particle on a surface and the shock pressure force produced by laser irradiation induced air breakdown.

Topics
Shock waves, Atmospheric processes, Laser peening, Laser beam effects, Laser materials processing, Chemical elements, Adhesion
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