LidroCUT – Ultrashort-pulsed Laser Processing in Liquids for Clean Dicing in One Process Step

Ultrashort-pulsed laser dicing in liquids, a combination of laser cutting and flowing liquids is a new technology for wafer dicing. This technology can cut any material at very high quality with virtually zero yield loss. This makes it possible to cut even complex material stacks with a single machine in one process. In detail, an ultra-short pulsed laser effectively cuts the material, while the liquid prevents heating of the substrate and adjacent structures, in addition to effectively flushing debris away from the kerf, keeping the sidewall and device clean. In this paper, the features of cleanliness, sidewall quality and thermal impact for silicon, copper on silicon and mold compound are presented.