Rapid reflectance-anisotropy spectroscopy as an optical probe for real-time monitoring of thin film deposition

We report on real-time spectroscopic reflectance anisotropy measurements carried out during the epitaxial growth of GaAs/GaAs (001). Our work is aimed to the study of fundamental processes occurring during the epitaxial growth of III-V semi-conductors. We show that during growth there is an oscillation in the surface strain associated to surface reconstruction, suggesting the existence of a mechanism of periodic build up-relaxation of the surface strain, indicating that the technique employed in this work may potentially distinguish between two reconstruction phases.