Research on laser-induced deep etching technology for through-hole processing of quartz glass

Traditional methods for processing through-holes in quartz glass have problems such as low separation efficiency and poor precision of the separation surface. Laser-induced deep etching technology is one of the core processes for glass through-hole processing. Its difficulty lies in the coordination of laser modification process parameters and etching parameters, taking into account the control of both etching processing efficiency and precision. In this paper, the changes of filaments during the modification of the inside of quartz glass by Bessel beams are analyzed through simulation. An auxiliary etching path method is proposed, which adds an auxiliary path, improving the dissolution efficiency of the hole core, and then the etching efficiency is enhanced. Moreover, the method of high-temperature constant-temperature ultrasonic-assisted etching is adopted for etching, which can improve the etching efficiency and assist the detachment of the hole core, realizing efficient through-hole processing. The results show that the laser parameters for laser modification are as follows: pulse width is 6 ps, the number of Burst sub-pulses is 2, the frequency is 200 kHz, the modification spacing is 4 μm, the processing speed is 0.1 mm/s, and the acceleration is 100 mm/s². The etching conditions are as follows: 40% KOH solution is used for constant-temperature ultrasonic-assisted etching at 100 °C for 17 h, which can realize the processing of a 100 μm aperture in a 3 mm-thick quartz glass. Laser-induced deep etching processing with the optimized parameters has broad application prospects.