超短脉冲激光微加工技术以其独特的优势,尤其是对硬脆难加工类宽带隙材料的精密处理,而使其成为微结构加工中的研究热点。利用飞秒激光微加工系统对宽带隙材料SiC的烧蚀特性进行理论和试验研究。应用扫描电子显微镜、原子力显微镜和光学显微镜等检测技术对样品的烧蚀形貌进行检测,以分析烧蚀区域的形貌特征及微结构质量。依据烧蚀孔径和入射脉冲激光能量之间的函数关系,得出SiC材料的烧蚀阈值为0.31J/cm2,并估算出光束的束腰半径为32μm。研究脉冲数目、重复频率和入射激光功率等对加工微结构形貌的影响规律,根据试验参数加工出形状规则的微孔结构,并对微结构的烧蚀形貌及材料的去除机理进行分析,为实现微结构的精密加工提供了重要的指导。
Ultra-short laser micromachining technology becomes the hottest research point in the field of micro manufacturing technology due to its unique advantages,especially for hard and brittle materials precision processing. By using the femtosecond laser micromachining system,the ablation characteristics and material removal mechanism of the wide band gap material SiC are theoretically and experimentally investigated. Scanning electron microscopy,atomic force microscope and optical microscopy are used to detect the ablation morphology of specimens so as to analyze the morphological characteristics and microstructure quality of ablation area. The ablation threshold of SiC material and the beam waist radius are obtained as 0.31 J/cm2 and 32 μm respectively on the basis of the functional relationship between ablation area and the laser energy. Besides,effects of pulse numbers,repetition rate and laser energy on the surface modification are explored,and a group of patterned microstructures are generated while their topography and the material removal mechanism are also analyzed,thus providing important guide for the precision machining of microstructures.