Estimate of dielectric density using spectroscopic ellipsometry

Abstract

The optical dielectric functions for hafnium oxide and hafnium silicate films were extracted from spectroscopic ellipsometry measurements and the density then calculated using a previously proposed method. The values obtained were then compared to those obtained using X-ray reflectometry. The optical dielectric functions for gadolinium oxide films deposited under various conditions were also extracted from spectroscopic ellipsometry measurements. It was found using medium energy ion scattering that gadolinium oxide films deposited using Gd[N(SiCH 3) 2] 3 and H 2O as precursors, contained significant levels of silicon and the silicon concentration was directly proportional to the wafer deposition temperature. This effect was also observed in the density measurements extracted from spectroscopic ellipsometry data.