Improvement sensitivity humidity sensor based on ZnO/SnO₂cubic structure

Abstract

ZnO nanorod, SnO2 nanoparticle and ZnO/SnO2 cubic structure were prepared using sol-gel immersion method. These three structures had been growth on top sputtered ZnO thin film. The surface morphology of all thin film were characterized using field emission scanning electron microscopy (FESEM) and energy dispersive X-ray spectroscopy (EDX). The prepared thin films were fabricated for humidity sensor application. The composite sensor ZnO/SnO2 cubic structure gave excellent sensitivity compare to ZnO nanorod and SnO2 nanoparticle. The improvement sensitivities of ZnO/SnO2 cubic structure were 22.5 times from ratio of R40RH% to R90RH% at 25°C. ZnO/SnO2 cubic structure had a great potential for humidity sensor application with good in repeatability and stability.