Photofacilitated Controllable Growth of ZnO Films Using Photoassisted Metal Organic Chemical Vapor Deposition

2012 
High-quality ZnO thin films were deposited on sapphire substrates using a photoassisted metal–organic chemical vapor deposition (PA-MOCVD) system. A controllable morphology evolution with varying degrees of crystallinity was observed. The microstructure of the film changes from a three-dimensional nanorod form to two-dimensional continuous dense form as the light irradiation intensity increases. A possible photofacilitated nucleation mechanism with a higher nucleation rate and density was proposed to explain the variation of the resulting ZnO formation. In this case, the crystallinity and optical properties of the epitaxial ZnO were also optimized, such that a low full width at half-maximum (0.079°) of the rocking curve could be obtained, similar to that of single-crystal ZnO. It was also found that the tensile strain in the films could be availably relaxed by added thermal energy and energetic photons provided by light irradiation. Additionally, temperature-dependent photoluminescence results behaving as...
    • Correction
    • Source
    • Cite
    • Save
    • Machine Reading By IdeaReader
    32
    References
    19
    Citations
    NaN
    KQI
    []