In this work, we grow different types of carbon nanotube (CNT) forests directly on AlN-based electroacoustic biosensors and study their functionalization efficiency. CNTs are used to increase the effective surface area of the sensor, pursuing a better sensitivity, without increasing the sensor capacitance. Here we use a general method for CNT bio-functionalization with specific receptors for targeted species. First, we make them hydrophilic. Next, we cover them with alternating polymers. Finally, we incubate their surface in an N-hydroxysuccinimide biotin solution. To study the functionalization homogeneity along the CNT length, Streptavidin conjugated with fluorescein isothiocyanate is used as the targeted species for confocal fluorescence microscopy characterization.
