ZnO Nanoparticles on Si, Si/Au, and Si/Au/ZnO Substrates by Mist-Atomisation

ZnO nanoparticles were prepared on Si substrates by a mist-atomisation technique. Precursor of aqueous solution zinc nitrate and HMTA were released on substrates heated at 200, 300, and 400°C confined in chamber box. The surface of Si substrate was varied, that is, gold-seeded Si (Si/Au), ZnO nanorods on Si/Au (Si/Au/ZnO), and just Si. The samples were subsequently analysed by X-ray diffraction, scanning electron microscopy, and photoluminescence (PL) spectroscopy to study their structural, surface morphology, and PL emission properties. Analysis from the XRD patterns of the films showed strong a- and c-axis lattice and of pure ZnO hexagonal wurtzite type. The crystallite size varied from 6 to 43 nm and was found to generally increase with increasing substrates' temperatures (). SEM micrographs revealed granular-like structure throughout. Shifts pattern of PL emission at ultraviolet and visible range was found to support size changes observed. Both substrate surface type and deposition temperature were found to significantly affect crystalline growth of ZnO nanoparticles. Chemical equations and justification for growth patterns are also suggested.