Resonant acoustic microsensor for photoacoustic detection

This paper describes the development of a photoacoustic microsensor for noninvasive glucose monitoring in human blood. The microsensor, based on capacitive sensing, is comprised of a resonant type cantilevered sensing element, sensitive to acoustic pressure and a rigid back plate electrode. Both parts of the sensor are fabricated separately. To eliminate external biasing requirement, an electret is formed on the back plate electrode using CYTOP. The fabricated sensing element and the back plate electrode are packaged in a housing for evaluation. In this study three different types of cantilevered sensing structures have been designed and tested. Based on the experimental study of the cantilever structures a novel photoacoustic microsensor has been fabricated and evaluated.