Fabrication of Microchannels by Using the CO2 Galvo Laser Marking Machine and Thermo-mechanical Sealing Method

Abstract

Abstract: Microchannel in microtechnology is a channel with a hydraulic diameter below 1 mm. Microchannels are primarily used in biomedical devices and microfluidic applications. Fabrication of microchannels has always been a complex task even at the world centres of excellence. This article addresses the fabrication techniques for creating microchannels using a 40W CO₂ Galvo laser marking machine. It was able to control the channel dimensions by changing the power, scanning speed, and scanning time of the laser source. The results show that the created channel width increased as the laser power increased and the scanning speed decreased. Similarly, the channel depth increased as the laser power increased. Successfully tested in the laminar flow and droplet modes, the created microchannels were sealed using the thermo-mechanical method at 220^oC. This is a new method for faster and cheaper production of microdevices that could be explored for sustainable development in the industry. The article concludes that with an appropriate solution, microchannels with minimal width and depth dimensions of 50 µm × 50 µm can be developed with channel roughness of 2-3µm.

Keywords: Microfluidics, microchannels, CO₂ marking machine, Galvo, mechanical sealing method.

References:

[1] G. Satish Kandlikar, Heat transfer and fluid flow in minichannels and microchannels. Amsterdam, The Netherlands: Elsevier B.V. 2006, pp. 450. ISBN 978-0-08-044527-4.
[2] D.B. Tuckerman, R.F.W. Pease, High-performance heat sinking for VLSI. IEEE Electron device letters 2 (5) (1981) 126-129. https://dx.doi. org/10.1109/EDL.1981.25367
[3] M.R. Salimpour, A.T. Al-Sammarraie, A. Forouzandeh and M. Farzaneh, Constructal design of circular multilayer microchannel heat sinks. Journal of Thermal Science and Engineering Applications 11 (1) (2019) 011001. https://dx.doi. org/10.1115/1.4041196
[4] Petra S. Dittrich, Lab-on-a-chip: microfluidics in drug discovery Nature 442 (2016) 210-224.
[5] D. Mark, Microfluidic Lab-on-a-Chip Plastforms: Requirements, Characteristics and Applications, NAPSA 24 (2010) 305.
[6] Shashi Prakash and Subrata Kumar, Fabrication of microchannels: A review, Proc IMechE Part B: J Engineering Manufacture 229 (8) (2015) 1273–1288.
[7] George M. Whitesides, The origins and the future of microfluidics, Nature 442 (2006) 368-384.
[8] Chee M.B. Ho, 3D printed microfluidics for biological applications, LabChip1 5 (2015) 3627.
[9] B. Ekstrom, G. Jacobsson, O. Ohman, et al. Microfluidic structure and process for its manufacturing. Patent WO 91/16966, 1990
[10] Dong Qin, Soft lithography for micro and nano patterning, NatureProtocals 5 (2010) 491-510.
[11] Shashi Prakash, Experimental and theoretical analysis of defocused CO2 laze microchanneling on PMMA for enhanced surface finish, JMM 27 (2016) 250.
[12] Beat Jaeggi, Time-optimized laze micro machining by using a new high dynamic and high precision galvo scanner, Proceedings (2016) 9735.