The role of heating and subsequent cooling for morphological modifications under pulsed laser irradiation

A numerical analysis is performed of the laser heating of metallic thin films deposited on electron microscope copper grids. A quasiuniform heating is predicted for the central zones within grid meshes, followed by a cooling with significantly different rates, depending on the analyzed point location relative to the grid mesh edge. This behavior is found to be in good agreement with the experimental evidence of the laser treated zones, as provided by electron microscopy investigation followed by a Fourier analysis of the recorded images. (orig.)