Identification of Volatile Organic Compound Mixtures with a Micromachined Quartz Resonator through Temperature Modulation with On-Chip Integrated Heater

This work presents a gas sensor array based on a micromachined quartz crystal resonators integrated with on-resonator thin-film heaters. The change in the functional material's gas adsorption behavior at different temperatures is utilized as a parameter for volatile organic compound (VOC) gas species identification. The sensitivity of a quartz resonator coated with a single gas sensitive material at four temperatures controlled by the on-chip heater are studied against six kinds of VOC gas mixtures at multiple concentrations. Principal component analysis (PCA) shows the ability of the device to identify the gas species with data from a single functional material. Combining the technique with multiple functional materials results in a hybrid physical-virtual sensor array which further enhances the efficacy of identification.