Synthesis of ZnO nanorods on a silicon substrate via hydrothermal route for optoelectronic applications

In the present work, we have synthesized ZnO nanorods (ZnO NRs) by using hydrothermal technique. The morphological, structural and optical properties of ZnO NRs were investigated using x-ray diffraction (XRD), scanning electron microscope (SEM) and UV-Vis absorption. XRD pattern confirms the deposited film was highly oriented crystalline ZnO NRs along [002] direction. SEM shows the formation of submicron and NRs morphology. The optical absorption studies depict that the optical energy gap of the film was 3.5 eV. The fabricated n-ZnO NRs/p-Si heterojunction photodetector exhibits rectification properties with an ideality factor of 2.2. The highest responsivity and quantum efficiency of the photodetector were nearly 0.27 A/W and 89% at 350 nm, respectively, without using buffer layer.