Quartz Crystal Microbalance (QCM) used as humidity sensor

This paper describes an application of Quartz Crystal Microbalance (QCM) us ed as humidity sensor. Moisture apparition is detected by using a QCM assoc iated with a Peltier module. When water condensation produced by the Peltie r cooling appears on the QCM, a change of mass on the crystal sensitive sur face results in the decrease of the resonant frequency. If we measure the d elay time between the beginning of Peltier supply and the apparition of wat er condensation on the quartz, we determine the relative humidity and the c ondensation velocity. A study of thermal transfer is first presented. Relat ive humidity measurements are then realised in a climatic chamber. A theore tical approach is finally compared with the experimental results. (C) 2000 Elsevier Science S.A. All rights reserved.