Resonating quartz-crystal cantilever for force sensing

A thin triangular cantilever sensor of AT-cut quartz crystal with a capability of self-sensing of vibration has been developed for force and nanometric sensing. The cantilevers fabricated by deep reactive ion etching with metal electrodes at the both sides have the thicknesses of 16 ~ 20 mum. Its force sensing principle using the quartz cantilever is based on the resonant frequency changes in the case that an external force is applied. The resonant frequency of shear vibration, up to 100.75 MHz, in the direction of the electrical axis is piezoelectrically excited, which is characterized by impedance measurements. The temperature property, frequency stability in resonance and Q factor stabilities show that the triangular cantilever sensor has a high potential ability for use in ambient atmosphere at room temperature. The 1st flexural vibration signal 118kHz of the cantilever was modulated into the thickness-shear vibration signal with a detection voltage of 5 muV