Micro processing on Cr films by Nd:YAG pulsed laser oxidation method

The surface oxidation of Cr films by Nd:YAG pulsed laser was studied using a combination of SEM, FESEM, AFM and XRD. The oxide growth is near homogeneous by laser irradiation at the lower power density but it presents hill-like growth mode by the laser irradiation at the higher power density. The formation of the thermal groove that is harmful for the next processing step of etching was considered as the relaxation of the initial tensile stress in Cr film and the lower diffusion rate during laser oxidation at the lower temperature. It is harmful for the next processing step of etching. The hill-like oxide growth is due to the rapid outward diffusion of Cr ions by laser oxidation at high-power density induced high temperature.