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Laser ablation characteristics in vacuum using excimer radiation at 248 nm and pulse durations of 17 ns for Al, Sn and Ti are presented. Ablation yields are measured as a function of input laser energy and target refreshment rate using gravimetric techniques. The laser ablation thresholds for Al, Sn, and Ti are found to be 3.15, 0.89, and 2.35 J∙cm-2, respectively. Ablation is inefficient, the majority of the laser input energy being shielded from the surface by the phenomenon of laser supported absorption, which results in heating of the nascent plasma. As the plasma becomes superheated during impingement of the laser pulse, energy is partially re‐emitted in the form of black‐body radiation. Mean kinetic energies of the ablation plasma species are determined by time resolved mass spectroscopy to be of the order of 5–50 eV. Target roughness and thin film morphology have been investigated using atomic force microscopy and scanning electron microscopy. Target roughness increases due to exfoliation and explosive boiling as the material is successively irradiated at a given point. Beyond a certain roughness, laser droplets are formed which propagate with the ablation plasma onto the growing film. Guidelines are presented for the rate of refreshment of exposed target material required to minimize incorporation of macroscopic material in the growing film. © 1996 American Institute of Physics.