Patent ID: 7053524

Claim:
A surface acoustic wave sensor or identification device having: a piezoelectric material, an interdigitated transducer (IDT) input/output mounted on the piezoelectric material for receiving a radio frequency (RF) signal and propagating a corresponding surface acoustic wave along a surface of the piezoelectric material, an IDT finger electrode array mounted on the piezoelectric material and operable to communicate with the IDT input/output for transmission of a modified RF signal from the device, said IDT finger electrode array having at least one finger electrode segment whose propagating characteristics are controlled to control the nature of the modified RF signal, a biolayer mounted on the piezoelectric material and associated with the finger electrode segment, and a fluidic chamber associated with the biolayer and which in use contains fluid which, if a predetermined substance to be sensed or detected is present, operates to modify the biolayer which in turn controls the nature of the modified RF signal.