Ultrafast and large-gap microwelding of glass substrates by selective absorption of continuous-wave laser into transiently excited electrons

Abstract

Glass-to-glass welding using ultrashort laser pulses is attracting attention. However, the low processing speed and the requirement for a small air gap between glass substrates have impeded its use in industry. In this study, we achieve ultrafast microwelding of glass substrates via the selective absorption of a continuous-wave laser into transiently excited electrons using an ultrashort laser pulse. This method increases the processing speed by a factor of 500 compared with the conventional method, and the allowable gap between the substrates by a factor of four, while maintaining a welding strength similar to that of conventional methods.