Finite element analysis of polymer-encapsulated ZnO nanowire-based sensor array intended for pressure sensing in biometric applications

Abstract

This work presents results of finite element analysis of an array of ZnO nanowires with bottom-bottom electrode configuration, which are integrated onto a multi-layer chip stack and encapsulated within a polymer. The dynamically-deformed array constitutes a representative part of a high-resolution pressure sensor intended for reliable identification of the smallest fingerprint features such as shape of the ridges and pores. Parametric study was performed in order to predict the most rational values of the Young's modulus and thickness of the encapsulation layer in terms of magnitude and variability of the piezoelectric signals. The results also demonstrate the impact of nanowire aspect ratio and load orientation on the generated electrical signals.