Ion Kinetic Energy Distributions and Mechanisms of Pulsed Laser Ablation on Al
Ion Kinetic Energy Distributions and Mechanisms of Pulsed Laser Ablation on Al
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DOI：
10.1021/jp805610h
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发表时间：
2008-10
影响因子：
3.7
通讯作者：
J. Apiñaniz;B. Sierra;R. Martinez;A. Longarte;C. Redondo;F. Castaño
中科院分区：
文献类型：
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作者：
J. Apiñaniz;B. Sierra;R. Martinez;A. Longarte;C. Redondo;F. Castaño
本文对纳秒脉冲激光烧蚀铝过程中喷射出的离子动能分布进行了详细的研究。对于刚刚超过阈值的激光影响，出现的离子符合移位的整齐麦克斯韦-玻尔兹曼-库仑（MBC）分布。对于高于~ 1.3 J/cm2的影响，Al+分布分为两个MBC贡献，在不同能量处达到峰值。结果表明，观察到的Al+离子分布有两个组成部分，一个是与直接多光子激光电离有关的快速组成部分，另一个是与固体中电子- Al0碰撞有关的缓慢组成部分。在所有Al离子分布的较高影响下观察到类似的行为，表明Al速率常数的电子碰撞电离比重组和其他可能的碰撞通道快。此外，库仑速度与离子电荷之间的线性关系以及离子的库仑能量与激光能量的关系表明，在激光能量的作用下，离子的库仑能量与激光能量之间存在着一定的关系。
A detailed investigation on the ion kinetic energy distributions of ions ejected in the nanosecond pulsed laser ablation of aluminum is reported. For laser fluences just over threshold, the emerging ions fit shifted neat Maxwell−Boltzmann-Coulomb (MBC) distributions. For fluences higher than ∼1.3 J/cm2, the Al+ distributions split into two MBC contributions peaked at different energies. It is demonstrated that the observed Al+ ion distribution has two components, one fast, correlated with the direct multiphoton laser ionization, and the other slow, associated with electron−Al0 collisions in the solid. A similar behavior is observed at higher fluences for all Al ion distributions indicating that the electron-impact ionization of Al rate constants is faster than that of recombination and other possible collision channels. In addition, the linear relationship between the Coulomb velocities and the ion charges and the behavior of Coulomb energy of the ions versus the laser fluence suggest the appearance of an...