MODIFICATION OF SILICON ABSORPTIVITY UNDER FEMTOSECOND LASER PULSE

Abstract

The article deals with theoreticalmodeling results of the combined influence of nonlinear absorptivity and absorption coefficient on the spatial and temporal distribution of the electron-hole plasma and the dynamics of the specific absorption flux in silicon under femtosecond laser pulse. It is shown thatincreased absorption of the hot electron gas makes the main contribution to the change in specific absorption flux. Obtained results were compared with the known views about the polariton mechanism,which is usedfor the interpretation of femtosecond laser silicon microstructuring. There aredemonstratedThe need to consider absorption capacity dynamics in the regimes assessment of ultra short laser semiconductor processing.

Keywords

• absorptivity
• skin-effect
• electron-hole plasma
• femtosecond surface microstructuring