In this article a multisample modification of variable angle spectroscopic ellipsometry is used to characterize ZnSe thin films prepared by molecular beam epitaxy on substrates formed by GaAs single crystals. Atomic force microscopy (AFM) is employed to characterize the morphology of the upper boundaries of these films. To interpret the ellipsometric data a relatively complicated physical model that contains a rough overlayer between the ambient and the ZnSe film and a transition layer between the GaAs substrate and the ZnSe film is employed. Several models of dispersion of the optical constants of the overlayers are examined to interpret the ellipsometric data. It is shown that the choice of overlayer dispersion model has a strong influence on determining the optical constants and dielectric function of the ZnSe films in the near-UV region. Within the visible region there are no differences between the overlayer dispersion models regarding determination of the ZnSe optical constants. The spectral dependences of the ZnSe dielectric function obtained are compared with those presented by other researchers. Further, by AFM it is shown that the upper boundaries of the ZnSe films are randomly rough and partially covered with small objects.
Articles you may be interested inEffects of well width and growth temperature on optical and structural characteristics of AlN/GaN superlattices grown by metal-organic chemical vapor deposition Appl. Phys. Lett. 95, 201906 (2009); 10.1063/1.3267101GaN hybrid microcavities in the strong coupling regime grown by metal-organic chemical vapor deposition on sapphire substrates Ex situ spectroscopic ellipsometry investigation of the layered structure of polycrystalline diamond thin films grown by electron cyclotron resonance-assisted chemical vapor deposition In situ monitoring of GaN metal-organic vapor phase epitaxy by spectroscopic ellipsometry
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.