NONSTATIONARY EFFECTS IN LASER-ABLATION OF INDIUM - CALCULATIONS BASED ON SPATIAL MOMENTS TECHNIQUE

The nonstationary averaging technique (spatial moments technique) is u sed for the solution of nonlinear heat equation describing laser ablat ion. The temperature dependencies of material parameters and the tempo ral profile of laser beam are taken into account. Nonstationary heat e quation is reduced to three ordinary differential equations for the su rface temperature, spatial width of the enthalpy distribution, and the ablated depth. Calculations have been done for laser ablation of indi um, where we study the influence of the duration and temporal profile of the laser pulse on the threshold fluence, Phi(th), the influence of temperature dependencies in material parameters on the overall ablati on kinetics (ablated depth versus laser fluence), the duration of the surface melt presence, etc.