使用掺镱光子晶体光纤飞秒激光放大系统作为加工光源, 利用激光诱导前向转移(LIFT)技术对铜膜进行加工, 产生纳米结构。通过控制飞秒激光光源参数, 得到不同纳米结构的金属薄膜。在功率较低时, 能够得到纳米团簇; 随着功率升高, 团簇尺寸变大; 到达一定功率时, 出现纳米线结构。通过实验分析了飞秒激光与材料相互作用时发生的物理过程。利用该机理, 对20, 40, 200 nm三种厚度的铜膜在相同实验条件下的实验结果进行比较, 获得了产生纳米团簇和纳米线结构薄膜的最佳条件。
Yb-doped photonic crystal fiber femtosecond laser amplification system is used as the processing light source, and nanostructures are produced from copper thin films by laser induced forward transfer (LIFT) technique. Metal films composed of different nanostructures can be obtained by controlling the parameters of femtosecond laser source. Nanoclusters are produced under lower power, and their sizes grow bigger with the power increasing. Then nanowire structures appear when the power rises to a certain level. Some physical processes of the interaction between femtosecond laser and materials are analyzed by experiments. On the basis of the mechanisms, experimental results of copper thin films with three different thicknesses of 20, 40, 200 nm are compared under the same experimental conditions. According to the results, optimum parameters are obtained for the generation of nanoclusters and nanowire structures.