1 research outputs found
Photofacilitated Controllable Growth of ZnO Films Using Photoassisted Metal Organic Chemical Vapor Deposition
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 strong
exciton effects confirmed the relatively excellent quality of the
obtained ZnO films