飞秒激光烧蚀YAG晶体的阈值及孵化效应研究  

Threshold and incubation effect of femtosecond laser ablation of YAG crystals

作　　者：商涛 邓国亮[1] 王俊 伍杰 蔡睿 陈茹波 许云龙 Shang Tao;Deng Guoliang;Wang Jun;Wu Jie;Cai Rui;Chen Rubo;Xu Yunlong(College of Electronic Information,Sichuan University,Chengdu 610065,China;Suzhou Everbright Photonics Co.,Ltd.,Suzhou 215163,China)

机构地区：[1]四川大学电子信息学院,四川成都610065 [2]苏州长光华芯光电技术股份有限公司,江苏苏州215163

出　　处：《红外与激光工程》2024年第3期84-92,共9页Infrared and Laser Engineering

基　　金：国家自然科学基金项目(61705149,61705148)。

摘　　要：孵化效应在超快激光烧蚀和加工的过程中起着重要作用。文中通过实验研究了波长为1030 nm的飞秒激光烧蚀YAG晶体的阈值和孵化效应。在单脉冲作用时,YAG表面发生“温和”烧蚀,具有较小的烧蚀孔径和深度;多脉冲作用时,由于孵化作用的影响,烧蚀阈值随着脉冲数的增加而显著降低。分别采用三种孵化模型,对比研究了其对YAG晶体烧蚀阈值的拟合效果。通过实验和拟合,得到单脉冲作用下烧蚀阈值为F_(th,1)=(12.27±3.56)J/cm^(2);多脉冲作用下,饱和孵化阈值为F_(th,∞)=(1.82±0.37)J/cm^(2)。该研究为飞秒激光精密加工中的能量和脉冲数等参数的控制提供了参考。Objective The incubation effect plays an important role in the process of ultrafast laser ablation and processing.This article investigates the threshold and incubation effect of femtosecond laser ablation of YAG crystals with a wavelength of 1030 nm.Under the shot of a single pulse,the YAG surface undergoes"mild"ablation,with a smaller ablation aperture and depth;When subjected to multiple pulses,due to the influence of incubation,the ablation threshold significantly decreases with the increase of pulse count and eventually converges to a stable value.This article uses three incubation models to compare and study their fitting effects on the ablation threshold of YAG crystals.Through experiments and fitting,it was found that the ablation threshold under single pulse shot is=(12.27±3.56)J/cm^(2);Under the shot of multiple pulses,the saturation incubation threshold is Fth;1=(1.82±0.37)J/cm^(2).This study provides a reference for the control of parameters such as energy and pulse number in femtosecond laser precision machining.Methods Femtosecond laser adopts external control mode,achieving precise control of the number of pulses through high-precision function/arbitrary waveform signal generator(DG1000Z)and high-precision electronic shutter.The control of laser power is achieved through the combination of a half-wave plate and a polarizer.The laser beam is focused on the surface of the sample using a microscope objective(NA=0.28)with 10×,and the sample is fixed on a high-precision stage.The surface morphology changes and damage processes can be observed online using a CCD camera.After the YAG crystal was irradiated by laser,the ablation morphology of the sample was observed by optical microscope(KEYENCE VH-Z500)and atomic force microscopy(Dimension ICON),and the diameters of different ablation pits were measured.The ablation threshold was obtained by drawing D^(2)–ln curve for calculating E_(th)(N)andωResults and Discussions The incubation coefficient S of Model I and the incubation coefficient k of Model II

关 键 词：飞秒激光 烧蚀阈值 孵化效应 孵化模型 

分 类 号：TB133[机械工程—光学工程]