Piezotronic-Based Magnetoelectric Sensor: Fabrication And Response

In the present work, magnetoelectric-piezotronic devices have been fabricated using exceptionally long (mm long) ZnO nano-and microneedles grown by the simple and versatile flame transport synthesis approach. The piezotronic response to an applied magnetic field has been investigated for state of the art magnetoelectric (ME) sensors containing AlN and PZT as piezoelectric phase as well as sensors based on ZnO nano- and microneedles, which are among the best described materials in terms of piezotronic applications. The current voltage (I-V) characteristics of the fabricated electronic sensor devices have been measured to understand the individual contributions of the piezoelectric and semiconducting properties. The experimentally obtained correlations between the piezotronic effect and the I-V responses have been fitted using appropriate theoretical models which have been discussed in detail. The current observations demonstrate that ME based piezotronic sensing devices have complementary roles, on one hand, the ME principle helps to get a better understanding of the piezotronic nature of quasi one dimensional (Q1D) ZnO nano-and microneedles, and on the other hand, the integration of a piezotronic effect leads to an improved sensitivity of the ME devices and hence to a better quality of ME sensors. (C) 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim