激光脉冲能量对激光烧蚀保护气体电离的影响  

Effect of Pulse Energy on the Ionization of Ambient Gas during Laser Ablation Target

作　　者：李尊营[1] 英海燕[1] 宋一中[2] 

机构地区：[1]山东临沂师范学院物理与电子科学系,山东临沂276005 [2]山东大学(南校区)材料科学系,山东济南250061

出　　处：《光谱学与光谱分析》2003年第4期654-656,共3页Spectroscopy and Spectral Analysis

基　　金：国家自然科学基金 (699780 1 1 )资助项目

摘　　要：用Ar气作保护气体 ,气压保持在一个标准大气压 ,用Nd :YAG脉冲激光烧蚀Al靶获得等离子体。利用时空分辨技术 ,采集了激光脉冲能量在 5 2 ,92 ,115和 14 5mJ情况下等离子体辐射的时空分辨谱。详细描述了 115mJ时等离子体的辐射特征 ,简要分析了其他脉冲能量下Ar的特征辐射规律。根据这些脉冲能量下Ar+ 特征谱线的分布规律 ,简要论述了Ar气体电离与激光脉冲能量的关系。讨论了环境气体电离机制 ,并对结果进行了简单解释。结果发现 ,在本实验采用的能量范围内 ,较高的脉冲能量更容易使环境气体电离 ,产生较强的Ar+ 离子辐射 ,且Ar+ 辐射持续时间较长。Ar was used as protecting gas, with ambient pressure being kept at 1 X 10(5) Pa. A plasma. was obtained by Nd: YAG pulsed laser beam ablating an aluminium target. With time-and space-resolved technique, time-and space-resolved spectra of the plasmas were acquired at pulsed laser beam energies: 52, 92, 115 mJ and 145 mJ respectively. The characteristics of the plasma radiating at 115 mJ were described in detail, and those of Ar+ radiating at the other energies were briefly analyzed. Based on the profile of Ar+ characteristically radiating at these pulse energies, the relation between the ionization of protecting gas and the pulsed laser beam energy was briefly discussed. The ionizing mechanism of the ambient gas was analyzed particularly. With the mechanism, the experimental results were reasonably, explained. As a result, from 52 to 145 mJ of the laser pulse energy, the higher the pulse energy was set, the easier the ionization of protecting gas became, the more intense the Ar+ radiation was, and the longer the radiation of Ar+ lasted.

关 键 词：激光脉冲能量 激光烧蚀沉积技术 气体电离 时空分辨谱 连续辐射 特征谱线 

分 类 号：O646[理学—物理化学]