No abstract

Micro bubbles in several tens micrometer diameter can act as effective structural elements of micro devices. In this study, the micro device employing the bubble motion is characterized. It has been experimentally revealed that bubble motion in micro channel is trapped at the channel branches. The local electrodes are set at a part of micro channel in order to control the bubble motion. Negatively charged bubble surface is received a certain force due to Coulomb's effect. This study will provide effective information to bioscience, medical science and agriculture engineering.

Single chip micro direct methanol fuel cell (SC-µDMFC) is attractive as a chip scale power source for micro electromechanical system (MEMS) devices. A multilayer structure is commonly employed for the fuel cell. The durability of SC-µDMFC should be mostly affected by interface energy. In this study, SC-µDMFC is fabricated by employing a photoresist / Pt electrode / PFSA film multilayer structure. The fabrication of SC-µDMFC (chip size of 2.0mm×2.0mm ×500µm) is succeeded without any film peeling. Consequently, maximum output power of 0.07µW is obtained. The film peeling of SC-µDMFC is also analyzed by the interface energy method. As a result, several layers of weak adhesion are predicted. However, the film peeling could not occur by the contribution of the other mechanical adhesion factors. The experimental results indicate the durability of the SC-µDMFC.