The Fabrication of Elcetrohydrodynamic Micro Pump

• Main Authors: Yu-Lin Huang, 黃鈺霖
• Other Authors: Lung-Jieh Yang
• Format: Others
• Language: zh-TW
• Published: 2002
• Online Access: http://ndltd.ncl.edu.tw/handle/58474497405889611682

碩士 === 淡江大學 === 機械工程學系 === 90 === Abstract : This research was proposed to utilize MicroElectroMechanical System (MEMS) technology to fabricate ElectroHydroDynamic (EHD) micro pump, and expected to use it in micro cooling system with intelligent functions of new generation. Gold and Indium Tin Oxide (ITO) was chosen to be available as electrodes for driving charges; two kind of electrodes were respectively deposited on Pyrex 7740 of glass by E-beam and sputter, and then to be micro-machined by using lift off and wet etching technology, respectively. The portion of channels was etched to establish each loop channel with a length of 1.5 cm, width of 100 μm, and depth of 30 μm after silicon bulk micro-machining. Finally, two methods such as anodic bonding and epoxy bonding can make electrodes to be bonded on channels. The first test was to use de-ionized water (D.I. water) as working fluid, and then was driven by applying direct-current voltage. Due to use D.I. water as working fluid in which occurred electrolytic phenomena during the test so that the adhesion layer on golden anodes caused oxidation losing function, even making golden wires were peeled off and broken down to result in the driving phenomena of fluid to be weaken obviously. A modified experiment was to choose ITO to be as the materials of driving electrodes. While applying 40 volt to drive working fluid, water-free ethanol with the maximum velocity of 87 nl/min was observed. Fortunately, ITO did not make metal wires to cause oxidation and break down, but still inducing the ITO electrodes with high electrical field to result in failure after driving it up to 10 minute continuously. The preliminary study on EHD micro pump to demonstrate two key issues have to be overcame, which one is to choose stable and reliable materials as electrodes, and the other is how to avoid D.I. water being electrolyzed if possible.