Kinetic energy distribution of ions in the laser ablation of copper targets

In this work we report on a study of the plasmas produced in laser ablation of copper targets by XeF ls351 nm. excimer laser irradiation. The kinetic energy of positive ions was measured by energy resolved time of flight mass spectrometry. Average kinetic energies of the Cuq ions of the order of 1–30 eV were observed, as a function of the laser pulse fluence. The experimental kinetic energy distributions show a double-peak structure. The first located at very low kinetic energy ;1 eV.can be related to a thermoionic component, whereas the second is strongly dependent on laser fluence. q1998 Elsevier Science B.V.