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IJAT Vol.9 No.6 pp. 668-673
doi: 10.20965/ijat.2015.p0668
(2015)

Paper:

Laser Modification of Silicon and Borosilicate Glass Wettability for Micro-Fluidic Systems

Yuko Aono, Wataru Shinohara, and Hitoshi Tokura

Department of Mechanical Sciences and Engineering, Tokyo Institute of Technology
2-12-1 Ookayama, Meguro-ku, Tokyo 152-8550, Japan

Received:
July 23, 2015
Accepted:
October 5, 2015
Published:
November 5, 2015
Keywords:
laser modification, wettability, micro-fluidic system, micro-channel, self-transportation
Abstract

A laser modification method to control the surface wettability of a silicon and borosilicate glass substrate is proposed and demonstrated. The wettability of the silicon surface decreases after 2.5 W laser irradiation without a change in surface morphology. When the laser power is greater than 4 W, it results in the formation of a 10-nm-deep groove and the wettability increases. These phenomena are caused by changes in the number of surface groups and morphology, respectively. On the other hand, the glass surface is modified by infrared laser irradiation and the treated surface is highly hydrophilic. Surface analysis by FT-IR indicates that the modification is the result of an increase in the number of silanol groups. The proposed modification method is applied to micro-fluidic systems. A modified line can function as a surface micro-channel. Furthermore, with a gradient in wettability, the micro-channel has the ability to self-transport water droplets.

Cite this article as:
Y. Aono, W. Shinohara, and H. Tokura, “Laser Modification of Silicon and Borosilicate Glass Wettability for Micro-Fluidic Systems,” Int. J. Automation Technol., Vol.9, No.6, pp. 668-673, 2015.
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