Ar环境下脉冲激光烧蚀粒子阻尼系数的空间分布

在10 Pa的Ar环境气体中，采用脉冲激光烧蚀技术，分别在半径为2.0，2.5，3.0，3.5和4.0 cm的半圆环不同角度处的衬底上制备了一系列含有纳米晶粒的Si晶薄膜。使用扫描电子显微镜、X射线衍射仪和拉曼光谱仪对其表面形貌和微观结构进行分析表征。结果表明，纳米Si晶粒的平均尺寸和烧蚀粒子的阻尼系数均相对于羽辉轴向呈对称分布，并随着与羽辉轴向夹角的增大而减小；同时，随着衬底半径的增加，晶粒平均尺寸和阻尼系数均逐渐减小。

Spatial distribution of damping coefficient of ablated particles prepared by pulsed laser ablation in Ar gas

The nanocrystalline silicon thin films were deposited on circular substrates with radiuses of 2.0 cm, 2.5 cm, 3.0 cm, 3.5 cm and 4.0 cm by pulsed laser ablation in argon gas of 10 Pa at room temperature. The surface morphology and microscopic structure of the films were characterized by scanning electron microscopy, X-ray diffraction analysis and Raman spectroscopy. The results indicate that both the average size of Si nanoparticles and the damping coefficients of ablated particles are distributed symmetrically relative to the plume axis, and decrease with increasing the angle between substrate and plume axis. Meanwhile, the average size of Si nanoparticles and the damping coefficients of ablated particles decrease as the radius of circular substrate increases.