Quality Glass Processing by Laser Induced Backside Wet Etching

Abstract

Laser Induced Backside Wet Etching (LIBWE) technique is applied for quality microprocessing of quartz. A direct-write approach is chosen to etch structures directly onto quartz. A diode pumped solid state (DPSS) 3rd harmonic Nd:YAG laser with a wavelength of 355 nm is used. High speed etching of glass is successfully carried out at a repetition rate of 10 kHz and a scanning speed of 100 mm/s using a galvanometer. With high speed processing, the amount of processing time is reduced greatly. Microfluidic channels are created by this technique within a short time. 3D surface scan shows that they are of good cross-sectional uniformity. Deposits are observed on the glass surface after the laser processing. X-ray photoelectron spectroscopy (XPS) analyses further reveal that this deposit is carbon related. Laser cleaning is applied to remove the contamination.