ガラスの広域パラメータ可変超短パルスレーザー加工

抄録

Laser processing has great potential for precision microfabrication of various materials including hard-to-machine materials, and has a high affinity for digital transformation. The productivity and quality of laser micromachining depend on multiple laser parameters. For those optimizations, the quick survey of laser parameters in wide range is vital. Recently, we have developed Yb-doped fiber chirped-pulse amplification system that can control various laser parameters in a wide range (pulse duration: 0.4 to 400 ps, repetition: single shot to 1 MHz, etc.). In this work, using this laser system, percussion micro-drilling of glass materials, such as silica glass and alkali-free boro-aluminosilicate glass, was investigated with pulse duration and fluence as wide-range variables. The repetition rate and number of shots were fixed at 1 MHz and 100. The ablation was observable when the pulse duration was below 30 ps and 50 ps for silica glass and alkali-free boro-aluminosilicate glass, respectively. From the ablation volume dependence on laser fluence, the ablation threshold of silica glass was much higher than that of alkali-free boro-aluminosilicate glass. The fast and comprehensive survey of ultrafast laser ablation of glass materials was demonstrated.