3D target shape retention within Selective Laser-induced Etching (SLE) via simulation of chemical etching

This study introduces a method to optimize the macroscopic shape of 3D glass components with microscopic components, fabricated using Selective Laser-induced Etching (SLE). SLE involves two steps: Laser modification and chemical etching. The challenge with fabricating large glass components is that longer etching times lead to deviations from the target geometry due to the etching of pristine material. To address this, the chemical etching step is simulated using a reaction-diffusion cellular automata system modeling the etching of fused silica by KOH. The simulation is calibrated and validated with measured etching rates and time series data of various geometries, also considering changes in local KOH concentration. An example optimization is demonstrated on a spray-burner nozzle with both macroscopic and microscopic features, adapting the initial model to ensure the final component closely matches the target geometry. This method enables precise geometrical optimization for large-scale glass components in SLE processes.