中文摘要：

采用脉冲激光烧蚀装置，在10Pa的氩气环境下，在1～6cm范围内调整衬底与靶的距离沉积制备了纳米Si薄膜。X射线衍射（XRD）谱和Raman谱测量均证实，纳米Si晶粒已经形成；利用扫描电子显微镜（SEM）观测了所形成的纳米Si薄膜的表面形貌。结果表明，随着靶衬间距的增加，所形成的纳米Si晶粒的平均尺寸减小（尺寸均匀性变差），在3cm时达到最小值（尺寸分布最均匀），而后开始增大（尺寸均匀性变差）。利用蒙特-卡罗（MonteCarlo）方法，对不同靶衬间距下烧蚀产物的输运动力学过程进行了数值模拟，得到与实验结果相同的结论。

英文摘要：

The nanocrystalline silicon films are prepared by pulsed laser ablation at the ambient Ar pressure of 10 Pa and the target-to-substrate distance from 1 cm to 6 cm. Both the X-ray diffraction （XRD） and Raman spectra indicate the films are nanocrystalline, which means that they are composed of Si nanoparticles. The surface morphology of the nanocrystalline silicon films is observed by using scanning electron microscopy （SEM）. The result shows that with increasing target- substrate distance, the average size of Si nanoparticles first decreases and reaches its minimum at 3 cm, and then increases. The transport dynamic process of the ablated particles in different target-to-substrate distances is numerically simulated by Monte Carlo method. The numerical simulations accord with the experimental results.