QCM Mass Sensitivity Analysis Based on Finite Element Method

The quartz crystal microbalance (QCM) mass sensitivity distribution based on a finite element method (FEM) is described in this paper. QCMs can measure the micromass through the measurement of resonance frequency; hence, it is widely applied in surface science, electrochemistry, biomedical science, and so on. It has the advantage of simple structure, label-free analysis, low price, and real-time output. However, the QCM measurement has a problem of lack of uniformity. After theoretical calculation and simulation, it was found that this deficiency is closely related to mass sensitivity. The QCM mass sensitivity depends on the metal electrode size, thickness, and shape. We calculated the QCM mass sensitivity based on Sauerbrey's equation, Bessel equation, and energy trapping. Then, the mass sensitivity was simulated based on FEM. The simulation result shows that the QCM mass sensitivity distribution is an approximate Gaussian curve. This method can help to better understand the mass sensitivity distribution, and give useful information to improve uniform of mass sensitivity distribution.