Authors: O. Katsuda, S. Saito and K. Takahashi
Affilation: Tokyo Institute of Technology, Japan
Pages: 426 - 429
Keywords: micromanipulation, liquid bridge, phase transition, condensation
The size of an object has decreased in the electrical and mechanical engineering field for fabricating highly functional microelectro-mechanical systems and photonic crystals. In micromanipulation, even if we can pickup micro-objects, it is very difficult to detach the micro-objects because adhesional force is dominant. Tanikawa et al. have detached micro-objects by using a micro-drop. This indicates that capillary force is effective in micromanipulation. Obata et al. have shown that capillary force can be controlled by regulation of liquid bridge volume. J. Liu et al., have fabricated a manipulation system named freeze tweezer based on freezing force to manipulate a wide variety of objects. Freeze tweezer has been controlled temperature by means of the Joule-Thompson throttling effect. However, they have not solved the detaching problem of adhesion phenomenon completely. In this study, our group manipulates micro-objects with capillary force by condensing water from the atmosphere. This condensed water forms a water bridge. The water bridge can be controlled by evaporation and condensation. A Peltier device is used for temperature control in order to achieve water phase transition. By using this method, we have achieved repeatable micromanipulation with simple equipments. We insist this wide applicable method can be effective in micromanipulation automation.