In situ monitoring of atomic layer epitaxy via optical ellipsometry

Abstract

We report on the use of time-resolved optical ellipsometry to monitor the deposition of single atomic layers with subatomic sensitivity. Ruddlesden-Popper thin films of SrO(SrTiO3)n=4 were grown by means of metalorganic aerosol deposition in the atomic layer epitaxy mode on SrTiO3(100), LSAT(100) and DyScO3(110) substrates. The measured time dependences of ellipsometric angles, $\Delta (t)$ and $\Psi (t)$, were described by using a simple optical model, considering the sequence of atomic layers SrO and TiO2 with corresponding bulk refractive indices. As a result, valuable online information on the growth process, the film structure and defects were obtained. Ex situ characterization techniques, i.e. transmission electron microscopy (TEM), X-ray diffraction (XRD) and X- ray reflectometry (XRR) verify the crystal structure and confirm the predictions of optical ellipsometry.

19 pages, 5 figures

References in corpus (1)

• Atomically precise interfaces from non-stoichiometric deposition

Cited by in corpus (1)

• Non-collinear and strongly asymmetric polar moments at back-gated SrTiO3 interfaces