Abstract
Material ablation using vacuum-ultraviolet (VUV) lasers is reviewed. High photon energy of VUV beam accomplishs clean ablation of transparent materials in the UV region such as polytetrafluoroethylene (PTFE) and fused silica with little thermal effect. A novel ablation scheme using multiwavelength excitation by coupling of VUV and UV laser beams is also presented. In this process, the VUV beams have two important roles, that is, photodecomposition of constituent atoms (stationary effect) and formation of excited state (transitional effect), although their energy is too small to ablate materials by themselves. The multiwavelength ablation provides great potential for high-quality microfabrication of wide band-gap materials such as fused silica, crystal quartz, sapphire, lithium niobate and SiC.
