Laser-induced-plasma-assisted ablation for glass microfabrication

Glass is a hard transparent material with many applications in Photonics and advanced display industries. It is a high challenge to achieve crack-free glass microfabrication due to its special material characteristics. Laser-induced-plasma-assisted ablation is applied in this study to get the high quality glass microfabrication. In this processing, the laser beam goes through the glass substrate first and then irradiates on a solid target behind. For laser fluence above ablation threshold for the target, the generated plasma flies forward at a high speed. At a small target-to-substrate distance, there are strong interactions among laser light, target plasma and glass materials at the rear side of the substrate. Light absorption characteristic at the glass substrate is modified since the plasma may soften and dope into the glass in the interaction area. To have a better understanding of this processing, signal diagnostics are carried out to study the dynamic interaction. It is found that glass microfabrication is closely related to laser fluence, target-to-substrate distance, laser spot size and laser beam scanning speed. With proper control of the processing parameters, glass surface marking, patterning and cutting can be achieved. With different materials as the targets, color marking of glass substrate can be obtained.