ENERGY DISTRIBUTIONS OF ATOMS AND MOLECULES PRODUCED BY LASER ABLATION.

Abstract

Summary form only given. The authors report measurements of energy distributions of Al atoms and AlO molecules produced by 248-nm excimer laser ablation of Al//2 O//3 . The atoms and molecules are detected by laser-induced fluorescence using a pulsed dye laser which is delayed with respect to the excimer laser pulse. With this technique, the desorbed species can be detected with excimer laser fluences below the threshold for formation of a laser-produced plasma and with greater than 1 monolayer of material ablated per pulse. Thus, the energy distributions of the desorbed species directly reflect the dynamics of the desorption process without significant interference from postablation collisions.