Novel technology for laser precision microfabrication of hard materials

Hybrid laser processing for precision microfabrication of hard materials, in which interaction of a conventional pulsed laser beam and another medium on the material surface leads to effective ablation, is reviewed. The main role of the medium is to produce strong absorption of the ns-laser beam tot the materials. Simultaneous irradiation of the UV laser beam with the VUV laser beam possessing extremely small laser fluence performs accurate ablation of the hard materials such as fused silica, crystal quartz, sapphire, GaN, SiC, etc. (VUV-UV multiwavelength excitation process). Metal plasma generated by the laser beam effectively assists high-quality ablation of transparent materials, leading to submicron grating fabrication and high-speed hole drilling of glass materials (laser-induced plasma-assisted ablation (LIPAA)). The detailed discussion includes ablation mechanism of hybrid laser processing and comparison of advantages and disadvantages with F2 laser ablation.