Ti:sapphire femtosecond laser ablation of silicon has been investigated by Langmuir probe and time-gated optical emission spectroscopy. The measured spectra show the presence of a fast ion population preceding the main plume core of slow ions and neutrals produced by a thermal ablation mechanism. By analyzing the fluence thresholds for the emission of the two ion populations, we provide clear experimental evidence that fast ions are ejected non-thermally from the sample surface as a result of the Si surface supercritical state induced by the intense ultrashort laser pulse irradiation.
Study of the plasma plume generated during near IR femtosecond laser irradiation of silicon targets / Amoruso, Salvatore; Altucci, Carlo; Bruzzese, Riccardo; DE LISIO, Corrado; Spinelli, Nicola; Velotta, Raffaele; M., Vitiello; X., Wang. - In: APPLIED PHYSICS. A, MATERIALS SCIENCE & PROCESSING. - ISSN 0947-8396. - STAMPA. - 79:(2004), pp. 1377-1380. [10.1007/s00339-004-2785-9]
Study of the plasma plume generated during near IR femtosecond laser irradiation of silicon targets.
AMORUSO, SALVATORE;ALTUCCI, CARLO;BRUZZESE, RICCARDO;DE LISIO, CORRADO;SPINELLI, NICOLA;VELOTTA, RAFFAELE;
2004
Abstract
Ti:sapphire femtosecond laser ablation of silicon has been investigated by Langmuir probe and time-gated optical emission spectroscopy. The measured spectra show the presence of a fast ion population preceding the main plume core of slow ions and neutrals produced by a thermal ablation mechanism. By analyzing the fluence thresholds for the emission of the two ion populations, we provide clear experimental evidence that fast ions are ejected non-thermally from the sample surface as a result of the Si surface supercritical state induced by the intense ultrashort laser pulse irradiation.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
