Nanocomposite sensitive polymeric films for SAW sensors deposited by the MAPLE direct write technique

A matrix-assisted pulsed laser evaporation direct write (MAPLE-DW) deposition technique was used to improve the properties of sensitive layers used in surface acoustic wave (SAW) sensors. In contrast with conventional deposition methods, MAPLE-DW allows the synthesis of uniform nanocomposite layers based on nanoparticles, in a special configuration that significantly reduces the energy loss by wave scattering. Ethanol, methanol, and toluene vapor were used as the target gases. The study compared sensors with polyethylenimine sensitive films and nanocomposite polymeric films based on SiO2/Si nanoparticles (deposited by spray coating), and nanocomposite layers based on SiO2 nanoparticles (deposited by MAPLE-DW). The sensors made from sensitive layers deposited by MAPLE-DW exhibited 3–5 times the sensitivity and 10–40 times the detection limit of the sensors deposited by spray coating.