CHARACTERISTICS OF ABLATION PLASMA PRODUCED BY INTENSE, PULSED, ION-BEAM

Characteristics of ablation plasma produced by the irradiation of an i ntense, pulsed, ion beam on targets, which has been known to be very e ffective in preparing thin films and is known as ion-beam evaporation (IBE), have been investigated experimentally by time-of-flight of ion- flux density measured by biased ion collector (BIC). With ion-beam pow er density of approximately 10(9) W/cm2, the velocity and the kinetic energy of the ablation plasma were measured at various positions from the substrate using a titanium or aluminum target. An analytic solutio n derived from one-dimensional hydrodynamic expansion into a vacuum ha s been developed for the IBE process. Using such a model, it is possib le to deduce the temperature in IBE from the signals of BICs. This met hod is also applicable to other intense pulsed energy sources such as lasers or electron beams.