Selective, Laser-Induced Etching of Fused Silica at High Scan-Speeds Using KOH

Selective, laser-induced etching (SLE) is a process which offers the possibility of machining hollow volumes into transparent materials with a huge freedom of geometry in 3D. Every 3D structure consists of single lines of laser-induced modifications. The knowledge of selectivity for etching of these single lines of modification is crucial to identify stable process windows for the machining of completely integrated, complex 3D structures. The selectivity of laser-induced etching of single line modifications is investigated in this study for a variation of repetition rate, pulse duration, pulse energy and feed rate for etching with KOH.