کد مقاله | کد نشریه | سال انتشار | مقاله انگلیسی | نسخه تمام متن |
---|---|---|---|---|
1593191 | 1002689 | 2012 | 4 صفحه PDF | دانلود رایگان |
![عکس صفحه اول مقاله: Zn- and O-polar surface effects on Raman mode activation in homoepitaxial ZnO thin films Zn- and O-polar surface effects on Raman mode activation in homoepitaxial ZnO thin films](/preview/png/1593191.png)
ZnO thin films were grown by metalorganic chemical vapor deposition on (0001) Zn- and O-polar surfaces of ZnO substrate. The surface morphology of these films was investigated by micro-Raman scattering and scanning electron microscopy. In the case of Zinc-polar face and using back scattering configuration, two new Raman bands were observed at 398 and 584.5 cm−1. They have been interpreted as quasi phonons TO (qTO) and LO (qLO) respectively. The origin of these modes was attributed to the particular morphology of ZnO films grown on Zn-polar face, which consists in cc-axis nano-platelets, randomly tilted from the substrate. qTO and qLO frequencies have been calculated using the model of Loudon. SEM observation is in agreement with our Raman interpretation.
► The morphology of homoepitaxial ZnO films was investigated by micro-Raman and SEM.
► Raman study of ZnO deposed on Zn-polar surface substrate reveals the quasi qTO and qLO modes.
► We showed that the disordered orientation of the ZnO platelets allowed qTO and qLO modes to occur.
► The Loudon model has been used to calculate the solid angle introduced by the optical collection.
► The inclination of the platelets was calculated using the Loudon model.
Journal: Solid State Communications - Volume 152, Issue 9, May 2012, Pages 794–797