THE NONLINEAR MULTIMODE THEORY OF DEFECT DEFORMATIONAL ORDERED SURFACE-STRUCTURES GENERATION BY STRONG LASER-BEAMS

The multimode nonlinear theory of formation of surface periodic point defect deformational (DD) structures is developed. The general set of coupled nonlinear kinetic equations for DD gratings of the Fourier amp litudes is derived and reduced to the rate equation with allowance for diffusion and drift in q-space. The conditions of generation of eithe r multimode or single-mode DD structures are investigated, and periods , times of formation, and stationary amplitudes of DD gratings are det ermined. The theoretical results are used for interpretation of previo usly obtained experimental results on the generation of DD gratings in Si under millisecond laser irradiation and under ion implantation.