Piezoelectric thin film pressure sensor made by atomic layer deposition of 002-oriented ZnO on Si3N4 membrane

In this work, we present a pressure sensor based on piezoelectric response of a thin 100 nm ZnO 002-oriented film grown using atomic layer deposition (ALD) technique on a commercial Si3N4 membrane. In contacts on top of the ZnO film allowed measuring the piezoelectric response laterally along the ZnO film induced by the pressure difference causing mechanical deflection of the membrane. The ALD of ZnO is the key process here, where the growth characteristics were investigated in order to obtain 002-oriented piezoelectric ZnO films. A linear response of this sensor in the 0.2-1.0 kPa range was recorded.