This article presents a comprehensive spectroscopic study of chemical phase separation in zirconium silicate alloys, (ZrO2)(x)(SiO2)(1-x), using Fourier transform infrared spectroscopy, x-ray photoelectron spectroscopy, extended x-ray absorption fine structure spectroscopy, and near edge x-ray absorption spectroscopy. These measurements are complemented by measurements of x-ray diffraction and high resolution transmission electronic microscopy imaging. This combination has been applied to Zr silicate alloys, providing the first comprehensive comparisons of the relative sensitivities of these spectroscopic techniques applied to micro- and nanoscale chemical phase separation of high-k dielectric alloys. (C) 2003 American Vacuum Society.