Table of Contents
Laser Chemistry
Volume 16, Issue 3, Pages 167-177

Photothermal Ablation of Polystyrene Film by 248 NM Excimer Laser Irradiation: a Mechanistic Study by Time-Resolved Measurements

Department of Applied Physics, Osaka University, Suita, Osaka 565, Japan

Received 25 July 1995

Copyright © 1996 Hindawi Publishing Corporation. This is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.


Laser ablation mechanism at 248 nm irradiation of polystyrene film was investigated and discussed. An ablation threshold was determined by etch depth measurement and nanosecond photographic observation. Temperature at the threshold was evaluated to be 370℃ by using an effective absorption coefficient which was confirmed by transmission measurement of the excitation pulse. The temperature was in good agreement with that of thermal degradation of the polymer, showing that 248 nm ablation of polystyrene was brought about by a photothermal process. Nanosecond photography upon the ablation could be well interpreted from the photothermal viewpoint. Moreover, dynamics of excited species revealed by nanosecond time-resolved luminescence measurements was inferred in relation to the ablation.