532nm皮秒脉冲激光对单晶硅的损伤特性研究

随着光电对抗和超短脉冲激光技术的发展,研究超短脉冲激光与单晶硅相互作用具有非常重要的理论和实际意义.为了进一步明确532 nm皮秒脉冲激光对单晶硅的损伤机理,本文开展了532 nm皮秒脉冲激光辐照单晶硅的损伤效应实验研究,测定了损伤阈值,明确了损伤机理,探讨了低通量下的脉冲累积效应.首先,利用波长为532 nm、脉冲宽...

Damage characteristics of a 532 nm picosecond pulse laser on monocrystalline silicon

With the development of optoelectronic countermeasures and ultrashort pulse laser technology,the study of the interaction between ultrashort pulse laser and monocrystalline silicon has a very important theoretical and practical significance.In order to further clarify the damage mechanism of 532 nm picosecond pulsed laser on monocrystalline silicon,we have conducted an experimental study to measure the damage threshold,clarify the damage mechanism,and discuss the pulse accumulation effect at low flux.Firstly,using a laser with a wavelength of 532 nm,a pulse width of 30 ps and a metallurgical microscope based on the 1-on-1 laser damage test method,the zero damage probability threshold is determined to be 0.52 J/cm².Secondly,the damage effect of a picosecond laser irradiated on monocrystalline silicon was studied under different laser fluxes,and it was found that the damage of 532 nm picosecond laser to monocrystalline silicon is manifested as heated-effect damage and plasma impact damage.The increase in energy density can be divided into three stages according to the main damage mechanism:thermal effect(0.52~3 J/cm²),thermal ablation(3~50 J/cm²)and plasma effect(>50 J/cm²),and the damaged areas are corresponded to different growth laws with the laser energy density,respectively.Finally,an experiment for the multi-pulse cumulative effect was carried out at a low laser flux and it was found that at a laser energy density of 0.52 J/cm²,the surface was irradiated continuously for 16 shots.The formation of a heat-affected zone confirms that the cumulative effect of multiple pulses can lower the laser damage threshold on monocrystalline silicon.