SEM characterization of carbon nanotubes based active layers of chemical sensors

Characterization method for active layers for microelectrodes of electrochemical and gas sensors using scanning electron microscopy (SEM) is presented. In order to achieve maximum sensitivity and selectivity of the sensor, it is necessary to obtain precise knowledge of electrode´s surface. Characterization was made using FEI Magellan SEM equipped with TLD secondary electron (SE) and CBS back-scattered electron (BSE) detectors, Energy-dispersive X-ray spectroscopy (EDS) and beam deceleration system. SEM at lower energies offers several advantages, among them the most important are: increase of material contrast, high ratio SE, BSE signal and noise, smaller interaction volume and elimination of charging effects.