Abstract
Micro-holes of some hundreds micrometer diameter were drilled on cemented tungsten carbide plates of 0.5 to 1mm thick by ultrashort laser pulses. Effects of laser light polarization, circular vs. linear, have been examined. Circularly polarized laser results in spherical shape holes while linearly polarized light results in elliptic shape hole exits. Laser induced periodic surface structures(LIPSSs) with size of 260 to 300 nm interval were found on the side of drilled hole. Effect of polarization on LIPSSs formation was also examined
