QCM measurement systems: Problems and performance analysis

This study focuses on assessing the metrological performance of Quartz Crystal Microbalance (QCM)-based measurements, specifically exploring the impact of the front-end circuits on overall measurement quality. The investigation employs two distinct measurement architectures designed to minimize errors related to hardware and software design. Two custom-designed front-end electronic circuits, one for oscillator-based (QCM-R) and the other for Quartz Crystal Microbalance with Dissipation (QCM-D) system, are operated under equivalent mechanical load conditions and compared. Measured parameters are obtained through accurate digital processing in the frequency domain, with experimental tests conducted in liquids of different viscosities. Results are compared to data collected using a commercial impedance analyzer as the reference instrument. Findings were consistent with those predicted by relevant models and highlight the criticalities related to measurements in the presence of significant dissipative phenomena.