Debris-Free Cutting of Quartz with Zero Kerf Width and Ultra-Low Surface Roughness Using Femtosecond Bessel Laser Beam Filamentation
Z-Q. Li, W. Guo, O. Allegre, C-G. Liu, W-Y. Gao, X-F. Wang, Z-X. Hou, K. Li, L. Zhang and L. Li
Quartz is a hard and brittle material that is difficult to cut with mechanical tools without generating microcracks and debris, leading to potential weakening of the material and scratches. Herein we present the findings of an investigation into high-quality quartz (JKS2) cutting with high uniformity and repeatability using a Ti:Sapphire femtosecond pulse non diffraction zero-order Bessel laser beam filamentation to induce a change in material refractive index followed by mechanical cleavage. The Bessel beam was generated by passing the laser beam through an axicon lens with a physical angle of 20.0°. Our experimental results show that vertical wall stealth dicing can be achieved with workpiece thicknesses of 0.5 mm and 1 mm with a zero cut kerf width and with no debris or microcracks on the cut surface. The cut surface roughness was below 340 nm Ra. The effects of pulse energy and scanning speed of Bessel beam on cleavage force and sidewall surface roughness were discussed.
Keywords: Ti:Sapphire femtosecond laser, quartz, (JKS2, non-diffraction, zero-order, Bessel beam, stealth dicing, filamentation