Absorption of femtosecond laser pulse in fused silica: experiments and modelling

N. Varkentina; O. Uteza; N. Sanner; B. Chimier; M. Sentis; T. Itina

doi:10.1117/12.872736

21 February 2011 Absorption of femtosecond laser pulse in fused silica: experiments and modelling

N. Varkentina, O. Uteza, N. Sanner, B. Chimier, M. Sentis, T. Itina

Proceedings Volume 7920, Laser Applications in Microelectronic and Optoelectronic Manufacturing (LAMOM) XVI; 792003 (2011) https://doi.org/10.1117/12.872736
Event: SPIE LASE, 2011, San Francisco, California, United States

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.

Citation Download Citation

N. Varkentina, O. Uteza, N. Sanner, B. Chimier, M. Sentis, and T. Itina "Absorption of femtosecond laser pulse in fused silica: experiments and modelling", Proc. SPIE 7920, Laser Applications in Microelectronic and Optoelectronic Manufacturing (LAMOM) XVI, 792003 (21 February 2011); https://doi.org/10.1117/12.872736

ACCESS THE FULL ARTICLE

INSTITUTIONAL
Select your institution to access the SPIE Digital Library.

SELECT YOUR INSTITUTION

PERSONAL
Sign in with your SPIE account to access your personal subscriptions or to use specific features such as save to my library, sign up for alerts, save searches, etc.

PERSONAL SIGN IN

No SPIE Account? Create one

PURCHASE THIS CONTENT

SUBSCRIBE TO DIGITAL LIBRARY

50 downloads per 1-year subscription

Members: $195

Non-members: $335 ADD TO CART

25 downloads per 1 - year subscription

Members: $145

Non-members: $250 ADD TO CART

PURCHASE SINGLE ARTICLE

Includes PDF, HTML & Video, when available