We report on the fabrication as well as on the optical and electrical characterization of ZnO hierarchical structure. ZnO hierarchical structure fabricated with sequence of ZnO films/ZnO rods/ZnO buffer/c-plane sapphire substrate by continuous controlling growth condition in metal organic chemical vapor deposition (MOCVD) system. A growth temperature used in this experiment was not exceed the temperature of 300 °C, which is very low compared to the previous results on the ZnO films or rods grown by MOCVD. There were no seams or cracks in the interfacial region between ZnO films and end of ZnO nanorods. Transmission electron microscopy (TEM) characterization showed that ZnO nanorods in hierarchical structure had the single crystal hexagonal wurtzite structure with <0002> growth direction. Growth mechanism of transition from two-dimensional (2D) growth to one-dimensional growth or from 1D growth to 2D growth analyzed in atomic scaled via high resolution TEM (HRTEM). Due to the film layers located at end of nanorods, the optical and electrical property of ZnO nanorods could be observed directly without any metal contact which demands complicated process. Only near band edge (NBE) emissions with very weak deep level emission are observed around 3.28 eV. This indicates that ZnO hierarchical structure grown by MOCVD possess a good optical quality and less interior defects.

• Legal notice:
  

  Copyright (c) Pielaszek Research, all rights reserved.
  The above materials, including auxiliary resources, are subject to Publisher's copyright and the Author(s) intellectual rights. Without limiting Author(s) rights under respective Copyright Transfer Agreement, no part of the above documents may be reproduced without the express written permission of Pielaszek Research, the Publisher. Express permission from the Author(s) is required to use the above materials for academic purposes, such as lectures or scientific presentations.
  In every case, proper references including Author(s) name(s) and URL of this webpage: https://science24.com/paper/7712 must be provided.

1. Improvement of light extraction efficiency in n-ZnO:Ga/p-Si heterojunction light emitting diodes by SiO₂ current-blocking layer
2. Characterization of n-Mg_xZn_1-xO/ZnO/p-GaN double heterostructure grown by pulsed laser deposition
3. Low temperature growth of ZnO thin film by metalorganic chemical vapor deposition
4. The effect of oxygen content on the electrical characteristics of ZnO films
5. Influence of underlying layers on the growth of 1-D MgZnO nanorods