Novel Micro-Laboratory on Piezoelectric Crystal

With the continuing development of biotechnology and nanotechnology, a miniaturized and integrated device that is capable of controlling and measuring a small droplet has become desirable. Therefore, we fabricated an integrated device by adopting surface acoustic wave (SAW) streaming to control a droplet and an interdigitated electrode (IDE) sensor to measure the impedance of the droplet. The integrated device is called a "micro-laboratory". In this work, a micro-laboratory was realized by fabricating an interdigital transducer (IDT) for generating SAWs and an IDE for measuring a droplet on a single piezoelectric crystal. In the experiment, water and glycerol were mixed by SAWs and water/glycerol mixtures were measured by the IDE sensor. From the result, we found that the mixtures were uniformly mixed by the SAWs. Moreover, as a new application, we fabricated a novel micro-laboratory using an isotropic material/matching layer/128YX-LiNbO3 structure (three-layer structure). By using the three-layer structure, a disposable and low-cost SAW device was realized. (c) 2009 The Japan Society of Applied Physics