采用波长为1040 nm、脉宽为388 fs、重复频率为100 kHz的飞秒激光对石英玻璃表面进行大深宽比微型凹槽的刻蚀。首先,通过面积推算法,实验测量得到石英玻璃的损伤阈值为10.61 J/cm 2。然后,采用单线刻蚀法,研究了激光单脉冲能量、扫描速度和扫描次数对微槽刻蚀深度和宽度的影响。最后,利用激光扫描振镜,使用螺旋环切法,有效地增大微槽深宽比。实验结果表明:激光单脉冲能量是影响微槽深宽比的主要因素,在激光单脉冲能量为110 μJ、扫描速度为100 mm/s、扫描次数为30的条件下,能够获得质量良好、槽宽50 μm且深宽比达5.4的石英玻璃微槽。

In this paper, we used femtosecond laser with a wavelength of 1040 nm, a pulse duration of 388 fs, and repetition frequency of 100 kHz to etch microgrooves with a large depth-to-width ratio on the surface of quartz glass. Firstly, the laser-induced damage threshold of quart glass was experimentally determined to be 10.61 J/cm ² by virtue of the area calculation method. Secondly, the effects of laser single-pulse energy, scanning speed, and scanning times on the etching depth and width of the microgrooves were investigated with a single-line etching method. Finally, applying spiral etching with assistance of a laser scanning galvanometer, we found that the depth-to-width ratio of the microgrooves could be increased significantly. Experimental results indicate that the laser single-pulse energy plays an important role on the depth-to-width ratio of the microgrooves. Besides, with a laser single-pulse energy of 110 μJ, a scanning speed of 100 mm/s, and a scanning times of 30, we obtain the high-quality microgrooves with a width of 50 μm and a depth-to-width ratio of 5.4 on the surface of quartz glass.