Investigation of wavelength effects on polycrystalline silicon damages using nanosecond pulse laser irradiation

Abstract

Based on polyvinylidene fluoride(PVDF) piezoelectric sensing technology, this paper investigated the damage mechanism of polysilicon irradiated by three wavelengths (1064 nm, 532 nm, and 355 nm) of nanosecond pulsed laser. According to the damage characteristics of the polysilicon, the thermal shock damage mechanism of laser irradiation on polycrystalline silicon has been studied, and the propagation law of laser shock waves in the brittle materials has been explored. The results show that the melt spatter phenomenon of the polysilicon surface is caused by melting from the heat generated when the material absorbs high-energy laser photons, combined with the vapour pressure and plasma pressure. The main cause of the polysilicon material’s cleavage and destruction is the laser thermal stress. The corrugated field around the material’s radiation area is mainly the result of the coherent coupling of optics and thermodynamics. The peak value of the laser shock wave in polysilicon shows a linearly distributed attenuation.