Share Email Print
cover

Proceedings Paper

Absorption of femtosecond laser pulse in fused silica: experiments and modelling
Author(s): N. Varkentina; O. Uteza; N. Sanner; B. Chimier; M. Sentis; T. Itina
Format Member Price Non-Member Price
PDF $14.40 $18.00

Paper Abstract

We present experimental and theoretical investigations of interaction of a femtosecond laser (450 fs pulse at 1025nm) with dielectric materials (fused silica) for the single-shot laser regime. The aim is to analyze and understand the complex physical mechanisms of laser energy absorption yielding to damage and /or ablation. We outline the distinction between the ablation and the damage thresholds for dielectric materials. The evolution of the reflection, transmission and absorption signals is studied as a function of fluence. The experimental curves are accompanied by a modelling, which takes into account the photoionization and avalanche ionization depicting absorption of the laser energy by the material. The incident pulse propagation into the material, the temporal evolution of the electron density, reflection and transmission illustrate the beginning and the duration of the laser pulse absorption. The magnitude of the absorption process is energy density sensitive and, with the increase of the deposited fluence, the onset of absorption is moved temporally to the beginning of the pulse. We show the influence of the effective electron collision frequency on the calculated values of reflection, transmission and absorption. The results are particularly relevant to high micromachining industrial processes.

Paper Details

Date Published: 22 February 2011
PDF: 9 pages
Proc. SPIE 7920, Laser Applications in Microelectronic and Optoelectronic Manufacturing (LAMOM) XVI, 792003 (22 February 2011); doi: 10.1117/12.872736
Show Author Affiliations
N. Varkentina, Lab. LP3, CNRS, Univ. de la Méditerranée (France)
O. Uteza, Lab. LP3, CNRS, Univ. de la Méditerranée (France)
N. Sanner, Lab. LP3, CNRS, Univ. de la Méditerranée (France)
B. Chimier, Lab. LP3, CNRS, Univ. de la Méditerranée (France)
M. Sentis, Lab. LP3, CNRS, Univ. de la Méditerranée (France)
T. Itina, Lab. Hubert Curien, CNRS, Univ. Jean Monnet (France)


Published in SPIE Proceedings Vol. 7920:
Laser Applications in Microelectronic and Optoelectronic Manufacturing (LAMOM) XVI
Bo Gu; Guido Hennig; Xianfan Xu; Hiroyuki Niino, Editor(s)

© SPIE. Terms of Use
Back to Top