The surface of a eutectic BiSn target was ablated by several series of pulses at different spots using an excimer laser with a wavelength of 351 nm and a pulse duration of 20 ns. Morphology of ablation craters formed under a different number of pulses was analyzed with a scanning electron microscope, an optical profilometer, and an energy dispersion spectroscope (EDS). Laser-induced breakdown spectroscopy (LIBS) measurements were taken for each crater with the last pulse in the series of pulses. The ratio of peak intensities (Bi I peak at 472.25 nm and Sn I 563.16 nm) of LIBS spectra for craters formed by different series of pulses decreased from maximum at a single pulse to a stable magnitude after a series of 70 pulses. EDS mapping of crater areas for different series of pulses shows a decrease in Bi atoms abundance, in correlation with the decrease in normalized intensity of Bi peak LIBS spectra. The change of the chemical composition in the ablation area is explained based on the Knudsen evaporation model. For the first time, pronounced hydrodynamic effects resulting in the formation of 50 μm-high rims were observed. The unusual morphology of the ablated area is explained on the basis of hydrodynamic effects and recoil pressure.The surface of a eutectic BiSn target was ablated by several series of pulses at different spots using an excimer laser with a wavelength of 351 nm and a pulse duration of 20 ns. Morphology of ablation craters formed under a different number of pulses was analyzed with a scanning electron microscope, an optical profilometer, and an energy dispersion spectroscope (EDS). Laser-induced breakdown spectroscopy (LIBS) measurements were taken for each crater with the last pulse in the series of pulses. The ratio of peak intensities (Bi I peak at 472.25 nm and Sn I 563.16 nm) of LIBS spectra for craters formed by different series of pulses decreased from maximum at a single pulse to a stable magnitude after a series of 70 pulses. EDS mapping of crater areas for different series of pulses shows a decrease in Bi atoms abundance, in correlation with the decrease in normalized intensity of Bi peak LIBS spectra. The change of the chemical composition in the ablation area is explained based on the Knudsen evaporation m...

中文翻译：

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BiSn 共晶的多脉冲激光烧蚀：非全等元素转移和形态分析

使用波长为 351 nm 和脉冲持续时间为 20 ns 的准分子激光器，在不同点处通过几系列脉冲烧蚀共晶 BiSn 靶的表面。用扫描电子显微镜、光学轮廓仪和能量色散光谱仪 (EDS) 分析了在不同脉冲数下形成的烧蚀坑的形态。激光诱导击穿光谱 (LIBS) 测量是对每个陨石坑与脉冲系列中的最后一个脉冲进行的。由不同系列脉冲形成的陨石坑的LIBS光谱的峰值强度比（Bi I峰在472.25 nm和Sn I峰在563.16 nm）从单个脉冲的最大值下降到一系列70个脉冲后的稳定幅度。不同系列脉冲的火山口区域的 EDS 映射显示 Bi 原子丰度下降，与 Bi 峰 LIBS 光谱归一化强度的降低相关。基于Knudsen蒸发模型解释消融区化学成分的变化。首次观察到显着的流体动力学效应导致形成 50 μm 高的边缘。基于流体动力学效应和反冲压力解释了烧蚀区域的异常形态。 使用波长为 351 nm 和脉冲持续时间的准分子激光器在不同点处通过多个系列的脉冲烧蚀共晶 BiSn 靶的表面20 纳秒。用扫描电子显微镜、光学轮廓仪和能量色散光谱仪 (EDS) 分析了在不同脉冲数下形成的烧蚀坑的形态。激光诱导击穿光谱 (LIBS) 测量是对每个陨石坑与脉冲系列中的最后一个脉冲进行的。由不同系列脉冲形成的陨石坑的LIBS光谱的峰值强度比（Bi I峰在472.25 nm和Sn I峰在563.16 nm）从单个脉冲的最大值下降到一系列70个脉冲后的稳定幅度。不同系列脉冲的陨石坑区域的 EDS 映射显示 Bi 原子丰度的降低，与 Bi 峰值 LIBS 光谱的归一化强度的降低有关。基于Knudsen蒸发量解释消融区化学成分的变化... 由不同系列脉冲形成的陨石坑的 LIBS 光谱的 16 nm) 从单个脉冲的最大值下降到一系列 70 个脉冲后的稳定幅度。不同系列脉冲的陨石坑区域的 EDS 映射显示 Bi 原子丰度的降低，与 Bi 峰值 LIBS 光谱的归一化强度的降低有关。基于Knudsen蒸发量解释消融区化学成分的变化... 由不同系列脉冲形成的陨石坑的 LIBS 光谱的 16 nm) 从单个脉冲的最大值下降到一系列 70 个脉冲后的稳定幅度。不同系列脉冲的陨石坑区域的 EDS 映射显示 Bi 原子丰度的降低，与 Bi 峰值 LIBS 光谱的归一化强度的降低有关。基于Knudsen蒸发量解释消融区化学成分的变化...