IMPROVED SPIN DYNAMICS IN SOFT-MAGNETIC FILMS FROM 2D ARRAYS OF STRIPES AND DOTS PATTERNED BY LASER-ABLATION

Alternative to photolithography process for fabrication of 2D arrays o f magnetic dots is proposed from a very simple, fast and low cost tech nique, of laser ablation. Magnetic films with different compositions, structures (NiFe, CoZr, FeN monolayers and [Co/Cu](n) multilayers) and thickness (from 100 to 300 nm) have been submitted at the focalisatio n point of an ionized argon laser (3W CW maximum power) to a lateral m ovement produced by a motorized X-Y translation stage. Tracks of parti al or total ablation down to the substrate can be realized with well d efined width from 3 to 100 microns, depending on the laser beam defocu sing and power and on the sample velocity. The possibility of differen t patterns corresponding to stripes, bars and square 2D arrays with di fferent shape factor is described with size decreasing from millimeter to micron scale. It is shown that laser sputtering can induce strong changes in both static and dynamical magnetic properties of the films as discussed from the magnetization processes of domain wall at low fr equency and the complex permeability in the microwave range.