SAW UV sensors using ZnO nanorods grown on AlN/Si structures

In this study, we demonstrate the ZnO nanorods grown on aluminum nitride (AlN)/silicon (Si) layered structure to obtain surface acoustic wave (SAW) UV sensor. The ZnO nanorods act as high UV sensing material due to large surface-to-volume ratio. The X-ray Diffraction (XRD) and photoluminescence (PL) spectra showed that the ZnO nanorods grown on AlN/Si had highly (002)-oriented and good optical properties. The piece of ZnO nannorods grown at center of two-port SAW delay line, which based on inter-digital transducer (IDT)/AlN/Si structure was fabricated and exposed under UV light. Resulting in the SAW UV sensor shifted a maximum of 26 kHz under the UV intensity of 0.6 mW/cm².