Design and fabrication of a nanofluidic channel by selective thermal oxidation and etching back of silicon dioxide made on a silicon substrate

• Published in: Journal of micromechanics and microengineering 2007-12, Vol.17 (12), p.2393-2397
• Main Authors: Wu, Changju, Jin, Zhonghe, Wang, HuiQuan, Ma, Huilian, Wang, Yuelin
• Format: Article
• Language: English
• Subjects: Applied fluid mechanics; Applied sciences; Electronics; Exact sciences and technology; Fluid dynamics; Fluidics; Fundamental areas of phenomenology (including applications); Instruments, apparatus, components and techniques common to several branches of physics and astronomy; Mechanical engineering. Machine design; Mechanical instruments, equipment and techniques; Microelectronic fabrication (materials and surfaces technology); Micromechanical devices and systems; Physics; Precision engineering, watch making; Semiconductor electronics. Microelectronics. Optoelectronics. Solid state devices
• ISSN: 0960-1317; 1361-6439
• DOI: 10.1088/0960-1317/17/12/001

Based on the law that the oxidation rate of Si decreases with the oxidation time, a method to fabricate a nanochannel is presented. In this method, the depth of the channel is precisely controlled by the oxidation time. Nanochannels are fabricated with depths of several tens of nanometers, width of 20 mum and lengths of several millimeters. SEM images show that the channel is fabricated well. It is shown that the flow rate increases linearly with the inlet pressure for water, NaCl solution and oil. Besides, the flow rate increases with the temperature. The capillary phenomenon is also observed in the nanochannel.