Annealing effects on optical properties of low temperature grown ZnO nanorod arrays

Vertically well-aligned ZnO nanorods on Si substrates are prepared by a two-step chemical bath deposition method and their structural and optical properties are examined by Raman and photoluminescence spectroscopy. The resonant Raman measurements have shown that the surface defects have played a major role in the as-grown sample and that the strong intensity increase in Raman scatterings is due to both outgoing resonant Raman scattering effect and deep level defect scattering contribution for ZnO nanorods.