Observation of the Initial Stage of Ion Assisted Deposition Films Using a Rotating-Analyzer Ellipsometer

Abstract

We have equipped an ion assisted deposition (IAD) system with a rotating-analyzer ellipsometer for in situ monitoring of the deposition process. The sensitivity of the measurements of the initial stage of deposition varies greatly with the ellipsometric parameters of the substrate. We propose the optimum conditions for the SiO2/Si substrate system for the observation of the initial stage of gold film deposition. The deposition of gold films on optimized silicon oxide substrates was observed in situ using the rotating-analyzer ellipsometer. The growth curves for the gold films were different from those for continuous layer growth in the initial stage. The critical thickness at which the growth mechanism became continuous layer growth varied with the ion current density of the IAD. The ion current density for the minimum critical thickness of gold films had an optimum value of 100 µA/cm2.