Growth, Optical Characterization and Modelling of ZnO Nanorods on Si, SiC and Macroporous Si Structure
A. Ferreira da Silva, M.V. Castro Meira, C. Persson, N. Gutman, A. Sa’ar, P. Klason, M. Willander
Universidade Federal da Bahia, BR
Keywords: nanorods, ZnO, SiC, macroporous
Abstract:1- Instituto de Física, Universidade Federal da Bahia, Ondina, Salvador-Ba, 40210-340, Brazil 2- CETEC-Universidade Federal do Recôncavo da Bahia, Cruz das Almas-Ba, 44380-000, Brazil 3- Department of Materials Science and Engineering, Royal Institute of Technology, SE-100 44 Stockholm, Sweden 4- Racah Institute of Physics and the Center for Nanoscience and Nanotechnology, the Hebrew University of Jerusalem, Jerusalem 91904 Israel 5- Department of Physics, Göteborg University, SE-412 96 Göteborg, Sweden 6- Dept. of Science and Technology (ITN), Linköping University, SE-601 74 Norrköping, Sweden Zinc Oxide (ZnO) and 4H-SiC are prominent materials with large applicability such as optoelectronic nanodevices and for instance ultraviolet detectors. There is lack of more information about optical transitions beyond the indirect band gap energy (BGE) of 4H-SiC and even more for ZnO direct BGE grown on the former material. Using the vapor-liquid-solid and the aqueous chemical growth methods we have grown ZnO nanorods on different substrates, such as quartz, n- and p-type silicon porous silicon and n-type 4H-SiC. The Scanning electron microscopy (SEM) are shown and compared for all samples. We have calculated the absorption and energy gap by employing a first-principle and a full-potential linearized augmented plane-wave (FPLAPW) method within the local density approximation (LDA). The absorption of ZnO nanorods, on different substrates, is lower than that of quartz substrate when photon energy is low. It is shown the strong effect of 4H-SiC on ZnO nanorods. Experiment and theory show a good aggreement when the optical energy gap is considered for both materials.