中文摘要：

采用脉冲激光沉积（PLD）技术,在烧蚀点正上方0.35 cm、距靶0.7 cm处引入Ar气流,保持环境气压0.3 Pa,烧蚀高阻抗单晶硅（Si）靶。在烧蚀点正下方0.35 cm,距靶0.5 cm、0.7 cm、1.4 cm、2.1 cm、2.8 cm、3.0 cm和3.5cm处水平放置衬底来收集纳米Si晶粒。利用原子力显微镜（AFM）、X射线衍射（XRD）、Raman散射对样品表面形貌和微观结构进行分析表征。结果表明：在引入气流前后,纳米Si晶粒的尺寸均随着与靶距离的增加而逐渐减小;在同一位置,引入气流比不引入气流晶粒尺寸小,面密度大;在3.0～3.5 cm处,不引入气流时的样品不再有纳米Si晶粒,而引入气流的还存在纳米Si晶粒。

英文摘要：

The nanocrystal silicon films were prepared by pulsed laser ablating with a high resistivity single crystalline Si target at the ambient pressure of 0.3 Pa of pure argon gas.A bunch of argon gas flow was introduced at 0.35 cm above the ablation point with the axial range of 0.7 cm.Nanocrystal Si films were deposited on pieces of glass or single crystalline（111） Si substrates lined up at a distance of 0.5 cm,0.7 cm,1.4 cm,2.1 cm,2.8 cm,3.0 cm and 3.5 cm away from the target.The morphology and microstructure of the samples were characterized by atomic force microscopy（AFM）,X-ray diffraction（XRD） and Raman scattering.The results showed that with or without gas introduced,the size of Si nanocrystal decreases as target-substrate distance increases.In the same position,compare with non-gas introduced,the one with gas introduced have smaller size,but higher surface density;At 3.0-3.5 cm,the sample without introducing gas is no longer nanocrystal,but the one with gas introduced remain nanocrystal.