Piezotronic Effect based ZnO Pressure Sensor with TFT Structures

This paper presents piezotonic effect based ZnO TFT pressure sensor with nanorods (NRs), which is different from the vertical structure of conventional piezoelectric sensors. The NRs were grown over the planar channels of TFTs. It is a medium of pressure amplification because of the small force transmission area. The fabricated sensor has 16 times higher sensitivity compared to a thin film without NRs. The effect of NRs was studied experimentally and with SPICE distributed modeling simulation. To explain these all, channel mobility is investigated as new possible sensing mechanism of the piezotronic pressure sensors with COMSOL simulation.