Imposed layer-by-layer growth with pulsed laser interval deposition

Abstract

In order to create crystal structures by depositing consecutive atomic or unit-cell layers of different materials, a layer-by-layer growth mode is a prerequisite: nucleation of each next layer may only occur after the previous layer is completed. We introduced a growth method based on a periodic sequence: very fast deposition of the amount of material needed to complete one monolayer followed by an interval in which no deposition takes place and the film can reorganize. This makes it possible to grow in a layer-by-layer fashion in a growth regime (temperature, pressure) where otherwise island formation would dominate the growth. Here, we present imposed layer-by-layer growth of homo-epitaxial SrTiO3 as monitored by high-pressure reflection high-energy electron diffraction (RHEED) and atomic force microscopy (AFM).