Crack-less Laser Machining of Alkali-free Glass by 2-Step Irradiation Using Multiple Wavelength Source

Abstract

This study aims at investigating the process of machining alkali-free thin glass using a picosecond pulsed laser. A 2-step irradiation method, involving both processes of property modification and machining improvement, is proposed using different laser wavelengths. An IR laser was first focused on the glass substrate for enhancing the light-absorption capability of the glass and a subsequent UV laser was engaged in machining the modified area for drilling through holes. The characteristics of laser modification and laser drilling were examined through varying laser processing parameters of irradiation and machining. The ultimate goal is to use lower UV power to complete laser drilling on alkali-free glass and obtain higher quality of drilling.