High-precision micro-through-hole array in quartz glass machined by infrared picosecond laser

Circle and triangle micro-through-hole arrays without cracks, chips, and debris were machined in 0.3-mm-thick quartz glass by picosecond laser (wavelength = 1064 nm, pulse width 12 ps) in air ambient. The diameter of each circle through-hole was 550 mu m, and the side length of each triangle hole is 500 mu m; 30 mu m spacing between the adjacent hole edges and the smooth machined surface with R (a) = 0.8 mu m roughness depicted the high precision of the high-density micro-through-hole arrays. The fundamental properties of the ps laser processing of quartz glass were investigated. The laser ablation threshold fluence of the quartz glass was determined as 3.49 J/cm(2). Based on the fundamental investigation, a quantitative design of the cutting path for micro-machining of the through-holes with various geometries in quartz glass was developed. The work presents a more practical ps laser micro-machining technique for micro-through-hole arrays in glass-like materials for industrial application due to the precise quality, flexibility in geometries, ease of manipulation, and large-scale application.