Thin Film Bulk Acoustic Resonator Vapor Sensors with Single-Walled Carbon Nanotubes-based Nanocomposite Layer

We demonstrate the successful operation of a chemical microsensor based on thin film bulk acoustic resonator (TFBAR) for organic vapor detection at room temperature. The TFBAR consists of a vibrating membrane of AlN/Si₃N₄ fabricated on silicon substrate and resonating at the frequency of 1.045 GHz. Using a nanocomposite layer based on Single-Walled Carbon Nanotubes (SWCNTs) and prepared by the Langmuir-Blodgett technique onto the TFBAR device as highly-sensitive nanomaterial, the sensing performance of TFBAR sensor has been evaluated both as a passive device by a network analyzer with phase and insertion loss responses, and as oscillator with frequency response. The vapor sensing characteristics of SWCNTs-based TFBAR sensor are presented illustrating interesting results.