Thin film bulk acoustic wave sensors with coatings of biological and
chemical materials, multiple electrode depositions and a piezo-active
thin film transducer layer are hosted on a substrate. The thin film bulk
acoustic wave sensor suite, or T-BASS, produces a low-voltage,
IC-compliant thickness-directed electric field that is substantially
uniform over a substantial portion of the active area of the BAW
structure. The BAWs produced are essentially extensional plane waves
propagating away from the substrate surface and having phase progression
substantially oblique to the substrate surface. For BAW applications
requiring sensing by an active layer, it would be most desirable to have
an electrode structure that is both IC-compliant and can be energized
from a low-voltage source of electrical energy. The thin film BAW sensors
are compatible with IC fabrication and processing techniques, such as
photolithography. Both single channel and multiple channel thin film bulk
acoustic wave sensors are provided.