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In this study, the mass fabrication of microelectrode tools for microelectrochemical machining (MECM) was studied using microfabrication processes. The cantilever type geometry of microelectrodes was defined by photolithography processes, and metal patterns were made for electrical contacts. Various fabrication processes were studied for the fabrication of microelectrode tools, such as wet etching, lift-off, and electroforming for metal layer patterning. MECM test results showed feasibility of the fabricated electrode tools. The microfabricated electrodes can be used as micromachining tools for various electrical micromachining of steel mold and parts of microdevices.

The basic concept and preliminary performance results of a miniaturized electroosmotic pump with diaphragms were included in the present study. The separation of an electroosmotic pumping liquid from a drug using diaphragms is mainly to have a freedom in choosing an electroosmotic pumping liquid and to achieve the optimal drug delivery with its preferable precise control. As a result, the maximum flow rate and current increased linearly according to the increment of applied voltage that is electric potential.

In the present study, we measured velocity vector fields around hoop rings at each divided sections by using a particle image velocimetry method. The ring model used in this study was made of brass with two different aspect ratios and the experiment is carried out in a circulating water channel. As a result, we can observe two counter-rotating vortical flow structures around each hoop regime that is attributed to the interaction between direct pass through flow of hoop center and the shear flow separated from sharp-edged end of ring hoop.

The biological flow characteristics inside a microchannel were investigated experimentally using a micro-particle image velocimetry (micro-PIV) method. The main objectives of this study were to understand the blood flow in micro-domain blood vessels and to identify the feasibility of nano-scale fluorescent particles for velocity measurement. The flow field was analyzed with a spatial resolution of 1 K ×1 K pixels at low Reynolds number flow. To obtain the spatial distributions of mean velocity, 100 instantaneous velocity fields were captured and ensemble-averaged. As a result, for the case of blood flow, there were substantial velocity variations in the central region of micro-channel due to the presence of blood cells in the blood flow.

A new method to fabricate microfluidic channel which has metal electrodes on side wall is presented. Three dimensional electrode patterns were deposited through the shadow mask on highly recessed surfaces of microchannel. Polymer microchannel was fabricated using polymer molding technique. Shadow mask for electrode patterning were fabricated using MEMS process. Electrodes were patterned on side wall of microchannel using shadow effects occurring at angled evaporation through shadow mask. The electrodes on side walls facing each other are expected to provide more sensitivity at bio-analysis devices based on impedance variation.