X-Ray Fluorescence Determination of Composition and Thickness of Nickel—Iron—Cobalt Thin Films: Application of Solution Techniques

Abstract

In computer-memory technology, it is important to know the composition and thickness of nickel—iron—cobalt thin films. These parameters affect the magnetic properties of the films and must be determined accurately for evaluation purposes. An x-ray fluorescence procedure was used in this work. Nickel—iron—cobalt thin-film standards were developed by a solution technique. Thin films in the approximate composition range of 79% Ni, 18% Fe, and 3% Co and thickness range of 600–1300 Å were analyzed. Precision of the thin-film compositional analysis yields coefficients of variation of ±0.02% for Ni, ±0.12% for Fe, and ±0.43% for Co. Accuracy is 0.04% for Ni, and 0.17% for Fe, and 0.34% for Co. Precision of the thickness measurement yields a coefficient of variation of ± 0.2%. Accuracy, checked against optical interferometric data, is ±10 to 20 Å (∼1%–2% at the 1000-Å level).