Morphology control of 1D ZnO nanostructures grown by metal-organic chemical vapor deposition

The morphology of ZnO nanostructures grown by metal-organic chemical vapor deposition under various growth conditions was examined by scanning electron microscopy. An increase in the growth temperature resulted in the formation of 1D nanostructures with diameters decreasing with increasing temperature. Vertically aligned nanorods with a needle-like tip shape were grown on a previously deposited homo-seed layer. Also the seed layer reduced the growth temperature of 1D nanorods. Low-temperature growth posterior to nanorod growth resulted in the formation of nanorods with an inverted graded diameter.