Enhancement of light transmittance for wafers bonded with thin Al films using atomic diffusion bonding and subsequent laser irradiation

Enhancement of light transmittance was examined for sapphire or synthetic quartz glass wafers bonded with thin Al films using atomic diffusion bonding (ADB). The results indicate that the thin Al film at the bonded interface diffuses into the wafer by subsequent laser irradiation, which enhances the light transmittance through the bonded interface.