Research of the laser cleaning technique based on opto-acoustic effect

Abstract

In this paper, the contaminants on the substrate surfaces are cleaned using Q-switched pulse laser irradiation, which with pulse duration typically about 20ns and wavelength typically in the 1064nm or 532nm. A new mechanism for laser cleaning is proposed, which based on opto-acoustic effect that breakdown of the air above the target is obtained by a laser beam, and a laser-induced shock wave is produced to remove the various pollutants on the solid substrate surfaces. This method is much more effective than traditional conservative cleaning techniques including the continuous wave laser cleaning, there are many advantages for this new laser cleaning technology, such as the dry treatment, non-contact, non-damage to the substrate, no environmental pollution, and energy-economic, and so on. We make the theoretical analysis for this physical model of cleaning contaminant in detail and provided some experimental results and photographs.