Estudio del comportamiento de sensores de gas basados en resonadores de cristal de cuarzo para altas frecuencias
Revista de Innovación Sistemática
Quartz crystal microbalance (QCM) sensors have been frequently used as micro-weighing devices, since they have demonstrated to be highly sensitive due to the frequency shifts ought to mass- increments stuck on the sensing film surface of the sensor. This kind of devices are normally used as arrays of sensors in systems known as Electronic Noses, for the detection and analysis of gases, fluids, and biological compounds among others. The sensitivity of the QCM sensors is directly proportional to
... ly proportional to the resonance frequency of the crystal. Therefore, increasing sensitivity implies using high frequency crystals above 20 MHz. Quartz crystals have been manufactured in two modalities: fundamental and overtone, the latter being used for frequencies between 30 MHz and 200 MHz. In this work, we present theoretical arguments as well as experimental results that describe the characteristics and differences in the performance of 30 MHz sensors in both modalities, in addition to other considerations in the behavior of these devices that cannot be observed from the analytical point of view, but from the point of experimental view.