Tuning the growth mode in organic molecular-beam epitaxy

Abstract

The growth process of molecular thin films deposited on an interacting crystalline substrate by organic molecular-beam epitaxy is monitored in situ by reflectance anisotropy spectroscopy (RAS). From the RAS signal evolution measured during the early stages of deposition, evidence is found of two opposite growth modes, namely layer-by-layer and island modes, obtained when changing the supersaturation of the vapor phase on the substrate.