A thermo temporal model of pulsed laser ablation of copper coated thin films on a polyimide substrate. (2017)

• Record Type: Journal Article
• Authors: Nammi, Srinagalakshmi; Shiby, Sooraj; Vasa, Nilesh J.; Balaganesan, G.; Mathur, Anil C.
• Is Part Of: International journal of precision technology. Volume 7:Number 2/3/4(2017)
• Page Start: 138
• Page End: 150
• Publication Date: 2017
• Subjects: laser micro machining -- plasma shielding -- parabolic reflector -- thin film scribing -- recession rate -- plasma temperature -- plasma velocity -- nanosecond laser ablation -- laser material interaction -- micro machining of copper thin films; Production engineering -- Periodicals; Mechanical engineering -- Periodicals; 670.5
• Languages: English
• ISSNs: 1755-2060

Abstract

A heat transfer model of nanosecond laser irradiation on a copper thin film coated on a polyimide substrate is developed and studied to understand the thermal influence on thin films during the laser ablation. Temperature distribution inside the target is calculated using heat conduction equation considering hydrodynamic boundary conditions. Effect of plasma shielding on the ablation process due to inverse bremsstrahlung is considered in the model. The study clearly shows that the shielding effect of plasma decreases the laser energy reaching the target surface and therefore reduces the depth of micro crater formed by a single pulse. A comparative study has been made for depth achieved for micro-craters fabricated on copper thin films in air using a Q-switched Nd 3+ :YAG laser with 6 ns pulse duration for various laser intensities. The simulation results are compared with experimental data for the laser ablation depth which is measured using 3D optical non-contact profilometer.