Technological features of selective laser etching in the processes of internal modification of optical quartz

A selective laser etching (SLT) technology has been developed and successfully applied for precision processing of quartz glass up to 2 mm thick. The technology has demonstrated efficiency for two operations: cutting and punching holes. The following parameters have been achieved: roughness, R_a = 0.2 μm and R_z = 0.4 μm; deviation from perpendicularity, 1°; and cutting width, from 10 to 45 μm. Technological intervals for pulse energy, speed, and frequency at which selective etching is possible have been identified. The maximum etching rate of laser-modified quartz glass with a hydrofluoric acid solution is 225 μm/h, indicating a selectivity of about 47 compared to the original glass.