A high frequency GaN Lamb-wave sensor device

Lamb-wave devices are characterized by high sensitivity to surface perturbations due to acoustic energy confinement in a thin piezoelectric membrane. In this paper, a Lamb-wave delay line device based on a single crystalline GaN membrane is presented. The observed operating frequency of 178.82 MHz was found to be in excellent agreement with numerical analysis predictions. The device as a chemical sensor was evaluated during the application of various concentrations of glycerol on the device surface; its ability to operate as a biosensor was also assessed during the detection of the specific binding of a protein (IgG) to the device surface.