Love-wave biosensors using cross-linked polymer waveguides on LiTaO3 substrates

The design and performance of Love-wave sensors using cross-linked poly(methyl methacrylate) waveguides of thicknesses of 0.3 to 3.2 mu m on LiTaO3 substrates are described. It is found that this laver-substrate combination provides sufficient waveguidance and electrical isolation of the interdigital transducers from the liquid environment to achieve low acoustic loss and distortion. In biosensing experiments, mass sensitivity up to 1420Hz/(ng/mm(2)) is demonstrated.