Piezotronic Interface Engineering on ZnO/Au-Based Schottky Junction for Enhanced Photoresponse of a Flexible Self-Powered UV Detector

Exploiting piezoelectric effect to engineer material interface has been confirmed as a promising way to optimize the performance of optoelectronic devices. Here, by using this effect, we have greatly improved the photoresponse of the fabricated ZnO/Au Schottky junction based self-powered UV detector. A 440% augment of photocurrent, together with 5x increased sensitivity, was obtained when the device was subjected to a 0.580% tensile strain. The enhancement can be attributed to the facility separation and extraction of photoexcites due to the formation of the stronger and expanding built-in field, which is a result of charge redistribution induced by piezoelectric polarization at the ZnO/Au interface. This study not only can strengthen the understanding of piezoelectric effects on energy devices but also can be extended to boost performances of optoelectronic devices made of piezoelectric semiconductor materials.