Principal Component Analysis Augmented Identification of Volatile Organic Compounds Using a Micromachined AT-Cut Quartz Resonator-Based Gas Sensor Array

In this paper, we demonstrate the ability of identifying ppm level of concentrations of three volatile organic compounds using micromachined quartz resonators. 100 nm films of functional polymers were deposited on the resonators for the identification of ethanol, acetone, and toluene. Adsorption of gas vapors by the functional polymer films results in resonance frequency shifts of the quartz resonators. Principal component analysis (PCA) was performed on the raw frequency shift data collected. PCA analysis is able to determine components that allow for the gas species identification. Further transformation of these components allows for clustering by concentration.