Theoretical consideration of high-sensitivity biosensor using shear horizontal acoustic waves in layered structures

Realization of high-sensitivity biosensors is required. Acoustic wave-based biosensors are promising because of their ability to detect immunoreactions. In this paper, a shear horizontal (SH) acoustic wave in layered structures, namely, the Love wave, is discussed on the basis of numerical calculations. To generate the Love wave, a 36YX-LiTaO3 was chosen as a piezoelectric substrate. SiO2, polymer, and gold were chosen as guiding layer materials. First, the phase velocity and propagation loss were calculated as a function of the layer thickness. Then, an additional mass layer was loaded on the guiding layer to simulate bio-layer deposition. Simulation results indicate that a highly sensitive biosensor was realized by using a gold guiding layer. © 2012 Wiley Periodicals, Inc. Electron Comm Jpn, 95(4): 27–;32, 2012; Published online in Wiley Online Library (wileyonlinelibrary.com). DOI 10.1002/ecj.10417