Effect of Different Ambient Atmospheres on the Damage Caused to Silicon by 1064-nm Laser Pulses

Abstract

A nanosecond-pulsed laser with a wavelength of 1064 nm was used to irradiate silicon, and the concentration of water mist and smoke was characterized through light transmission. The drift and scattering effects of the laser propagation atmosphere (water mist and smog environment) on the laser and the influence of different ambient atmospheres on the effect of the laser irradiation on silicon were studied. Research has shown that when a laser passes through a water mist environment, as the laser transmission ratio increases, the diameter of the exit spot increases, and the diameter of the damage induced to single-crystal silicon increases approximately linearly. The erosion damage is enhanced, and a mixture of heat and stress damage occurs. Smoke is a simulated haze environment, and the attenuation effect of the aerosol content on the laser in a smoke environment depends on the particle size and concentration. When the laser transmission ratio is the same, the diameter of the particles is small, and the corresponding particulate matter concentration is large. The smaller the particle size, the larger the particle concentration corresponding to a different laser transmission ratio. When the laser energy of the target is the same, the shape and size of the export laser change as the laser passes through fog; furthermore, the damage shape is no longer circular, but it is rather stretched and deformed along a specific direction. This study can provide a reference for laser processing, far-field laser applications, and atmospheric optics.