Investigation and Analysis of Zinc Phthalocyanine Films for Resonant Gas Sensor Applications

Thin films of Zinc Phthalocyanine (ZnPc) with a range of different substitutes have been investigated as chemical active layers for sensing selected organic vapour such as (Ethanol, Toluene) by a standard Quartz Crystal Resonator (QCR) based sensor with fundamental resonance 10MHz. Adsorption of vapour onto the films surface has been realized by monitoring resonance spectra. An equivalent circuit (BVD circuit) has been used to extract parameters related to film viscosity and thickness by fitting experimental admittance spectra of QCR around resonance frequency. Moreover, film properties and characterization was obtained from QCR measurements in conjunction with suitable data analysis. Validation of film characteristics has been determined using complementary methods such as Ellipsometry, UV- Visible absorption Spectrophotometer and AFM.