激光烧蚀金属Al诱导发光的动力学研究

Radiation mechanism of pulsed laser ablation of metal Al

利用时间分辨的光谱测量技术,测定了XeCl紫外激光在不同条件下烧蚀金属Al诱导产生光谱线及其强度随时间的分布.结果表明:等离子体辐射光谱线由原子光谱线、一价离子光谱线及连续辐射背景光组成.Al原子光谱线的辐射强度与持续时间为最大,一价离子光谱线次之,以连续辐射背景光为最小.对激光烧蚀金属诱导发光的机理进行了探讨.等离子体中连续辐射背景光来自高能电子的韧致辐射和电子与离子的复合,原子光谱线和一价离子光谱线主要来自等离子体中电子与离子的复合.用此机理定性地解释了所观察到的实验现象.

Time-resolved measurement of plasma emission spectra by pulsed XeCl excimer laser ablation of Al under different conditions is reported. The experimental results show that plasma emission spectra are composed of atomic spectrum, univalent ion spectrum and continuous radiation. The atomic spectrum intensity and duration is most significant, the next is the univalent ion spectrum, the continuous radiation is weakest. The detailed mechanism of species excitation is discussed. The continuum radiation comes from electron bremsstrahlung and recombination of electron and ion, the primary atomic and univalent ion excitation originate from recombination of ion and electron. The experimental results are qualitatively explained with the mechanism.