Laser cutting chemically strengthened glass

Krailling, Germany - Chemically strengthened glass has become integral in advanced smart phones, tablets, and other portable electronics. It offers superior hardness and scratch resistance, but it presents challenges in production. The deeper the chemically strengthened layer, the more difficult it becomes to cut the glass with conventional methods.

The InnoLas laser cutting process allows cutting of chemically strengthened glass with a layer thickness of 50 micron or more, requiring no or only little post processing. Additionally, this InnoLas process enables high quality laser drilling and laser cutting of inner contours and features (e.g., holes or slots) into chemically strengthened glass without chipping, micro-cracks, and breakouts.

"InnoLas laser cutting has successfully cut glass with DOL of 50 micron and above and demonstrated perfect yield at thick layers. This is a much higher yield process than presently available with other laser cutting methods, resulting in excellent surface quality," said Richard Grundmüller, CEO. "Post processes, such as grinding and polishing are reduced to a minimum."

Rapidly advancing glass technology is developing harder and more scratch resistant products, resulting in thicker ion exchange layers. Thus, it becomes more difficult to use conventional cutting techniques because tension-compression in the glass grows, and its tolerance for any kind of perturbation decreases. Conventional laser cutting is based on rapid heating processes, leading to vaporization and material removal. This process is not only slow, but will lead to low yield due to micro-cracks, chip-outs and a rough surface finish. The necessary subsequent grinding and polishing steps are costly and time consuming.

InnoLas laser cutting employs specially tuned lasers that cut brittle materials. This technique has demonstrated good yield, and it allows cutting features, holes, chamfers, and more, in chemically strengthened glass.