Photochemical and photothermal model for pulsed-laser ablation

M. Sadoqi, S. Kumar, Y. Yamada

Research output: Contribution to journalArticle

Abstract

A model of the interaction of UV laser pulses with organic polymers is presented. The three distinct features of this model are as follows: 1) It combines photochemical and photothermal processes for breaking bonds. 2) It tracks the percentage of bonds broken where the higher dissociative states are not allowed to relax back to the lower states. 3) The model does not need an experimentally inferred value of threshold fluence to determine the onset of ablation. The mathematical model presented here is based on the system of a two-photon absorption model, where sets of rate equations that include radiative transport and energy absorption are solved. Solutions of this model are discussed, and the results are shown to compare well with experimental etch depth vs fluence curves from the literature for a wide range of pulse widths from 7 to 300 ns. parametric results are also presented for 193- and 308-nm UV laser wavelengths for different laser and polymer parameters. The dependence of the temperatures and ablation depths for different laser fluences and widths of the laser pulses are obtained.

Original languageEnglish (US)
Pages (from-to)193-199
Number of pages7
JournalJournal of Thermophysics and Heat Transfer
Volume16
Issue number2
StatePublished - Apr 2002

Fingerprint

Laser ablation
Pulsed lasers
laser ablation
pulsed lasers
fluence
Ablation
ultraviolet lasers
ablation
Lasers
Laser pulses
lasers
Organic polymers
Radiative transfer
polymers
energy absorption
Energy absorption
pulses
mathematical models
Polymers
pulse duration

ASJC Scopus subject areas

  • Fluid Flow and Transfer Processes
  • Physical and Theoretical Chemistry
  • Mechanical Engineering

Cite this

Photochemical and photothermal model for pulsed-laser ablation. / Sadoqi, M.; Kumar, S.; Yamada, Y.

In: Journal of Thermophysics and Heat Transfer, Vol. 16, No. 2, 04.2002, p. 193-199.

Research output: Contribution to journalArticle

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