Photodeposition sputtering of titanium and TiN thin films

Abstract

The interaction of any energy-carrying beam with solids leads to the degration of the solid crystals. The bombarded surface is sputtered and many effects on the atomic, microscopic and macroscopic scales can be observed. Very few experiments have been performed on the photodeposition sputtering of thin films, and the results obtained have been attributed to a variety of processes. In this work the results of the sputtering of and the morphological changes in titanium and TiN thin films induced by a point-focused neodymium-doped yttrium aluminium garnet laser beam are presented. The morphological changes, the shape and the size of the damaged area as functions of the laser beam density and the film thickness were investigated by scanning electron microscopy and profilometry studies. The results of the laser-induced damage have shown that the applied laser power density (in the range from 2 × 10 7 to 9 × 10 9W m −2) and the film thickness (from 22 to 2200 nm) were two very important parameters which strongly influenced the growth of the damage (exfoliation, hydrodynamic and thermal effects). The sputtering yield is a function of the laser beam power density. Its value increases with increasing power density and after reaching a maximum begins to fall owing to the plasma screening effect of the target.