Fast Laser Drilling on SiC-CMC Using Hybrid ArF Excimer Laser

Deep ultra-violet (DUV) lasers, in the spectral range of around 200 nm to 400 nm, are attracting attention to laser micromachining, since, due to its high photon energy, DUV light can cut atomic and molecular bonds in various wide bandgap materials directly and reduce thermal effects. Hybrid ArF excimer laser, consisting of a solid-state laser including high harmonics generation process as a seed light source and an ArF excimer amplifier, can generate DUV light at the wavelength of 193 nm with several millijoules pulse energy [1]. Although SiC has both high heat resistant temperature (1600 °C) and high thermal conductivity (270 W/m.K), the ArF photon (6.4 e V) can cut the Si -C bond (3.2 e V) directly, and thus, no cooling gases nor fluids were required. In this report, we demonstrate a fast laser drilling on SiC ceramics matrix composite (SiC-CMC) using the hybrid ArF excimer laser.