Numerical simulation on the temperature field induced by a nanosecond pulsed excimer laser in the phase-change film

• Published in: Thin solid films 2014-01, Vol.551, p.102-109
• Main Authors: Liu, F.R., Han, X.X., Bai, N., Zhao, J.J., Chen, J.M., Lin, X.
• Format: Article
• Language: English
• Subjects: Composition and phase identification; Condensed matter: structure, mechanical and thermal properties; Cooling; Exact sciences and technology; Excimer lasers; Finite element model; Heat conduction; Heating; Heating/cooling rate; Lasers; Mathematical models; Nanostructure; Phase-change material; Physical properties of thin films, nonelectronic; Physics; Surfaces and interfaces; thin films and whiskers (structure and nonelectronic properties); Temperature distribution; Temperature field; Thermal stability; thermal effects; Thin film structure and morphology
• ISSN: 0040-6090; 1879-2731
• DOI: 10.1016/j.tsf.2013.11.092

In the paper, a three-dimensional finite element model was developed to demonstrate the temperature field induced by a nanosecond pulsed excimer laser in the phase-change film. The numerical model was established with an assumed rectangular temporal profile, following the continuous medium heat conduction theory with semi-infinity heat conduction. It showed that the temperature variation followed the exponential relation in both the heating/cooling procedures, and the whole heating/cooling process was divided into four regions I–IV, namely rapid heating region I and equilibrium heating region II in the heating process as well as quick cooling region III and equilibrium cooling region IV in the cooling process. The heating/cooling rates were then fitted from the temperature variation curve. The calculated heating/cooling rates were in the scale of 108–1011K/s for the nano-scale pulse radiance. Furthermore, the effects of laser fluence and pulse duration on the temperature field were investigated. It was noted that the effect of pulse duration was focused on regions II and III, while the heating rate in region I was mainly determined by laser fluence. •A finite element model was developed in the paper.•The temperature field induced by a short pulse laser was elucidated.•The heating/cooling rates were obtained in the scale of 108–1011K/s.•The effects of laser fluence and pulse duration were also studied.