Applied Science and Convergence Technology 2010; 19(4): 293-299
Published online July 1, 2010
Copyright © The Korean Vacuum Society.
Su Min Jeon , Min Su Kim , Ghun Sik Kim , Min Young Cho , Hyun Young Choi , Kwang Gug Yim , Hyeoung Geun Kim , Dong-Yul Lee , Jin Soo Kim , Jong Su Kim , Joo In Lee , Jae-Young Leem
Vertically aligned ZnO nanorods on Si (111) substrate were prepared by hydrothermal method. The ZnO nanorods on spin-coated seed layer were synthesized at 140℃ for 6 hours in autoclave and were thermally annealed in argon atmosphere for 20 minutes at temperature of 300, 500, 700℃. The effects of the thermal annealing on the structural and optical properties of the grown on ZnO nanorods were investigated by X-ray diffraction (XRD), field-emission scanning electron microscopy (FE-SEM), photoluminescence (PL). All the ZnO nanorods show a strong ZnO (002) and weak (004) diffraction peak, indicating c-axis preferred orientation. The residual stress of the ZnO nanorods is changed from compressive to tensile by increasing annealing temperature. The hexagonal shaped ZnO nanorods are observed. The PL spectra of the ZnO nanorods show a sharp near-band-edge emission (NBE) at 3.2 eV, which is generated by the free-exciton recombination and a broad deep-level emission (DLE) at about 2.12∼1.96 eV, which is caused by the defects in the ZnO nanorods. The intensity of the NBE peak is decreased and the DLE peak is red-shifted due to oxygen-related defects by thermal annealing.
Keywords: 산화아연,나노막대,열처리,X-ray diffraction,photoluminescence,ZnO,Nanorods,Annealing