Morphology transition of one-dimensional ZnO grown by metal organic vapour phase epitaxy on (0 0 0 1)-ZnO substrate

Metal organic vapour phase epitaxy (MOVPE) has been used to successfully grow one-dimensional (1D) ZnO deposits on (0 0 0 1)-ZnO substrate. Dimethylzinc–triethylamine and nitrous oxide were used as zinc and oxygen sources, respectively, with nitrogen as the carrier gas. Vertically aligned 1D ZnO structures were observed along the c-axis by using lower VI/II mole ratio R_VI/II<2025 and/or high growth temperatures (Tg>800 °C). The diameter, length, density and the mechanism of formation could be controlled with the growth time. Scanning electron microscopy (SEM) shows different structures, i.e., sharp-top, flat-top and open-top with slim bottom and large-top one-dimensional ZnO. A good structural quality was revealed by X-ray diffraction rocking curve with a full-width at half-maximum (FWHM) varying from 40 to 92 arcsec with increasing growth time.