X-ray Diffraction Analysis of Thin Metal Films with Magnetic Layers of Fe-Cr-Co Alloy

Abstract

The aim of this study was to determine the phase composition of the structures of permanent magnet fi lms with layers of a Fe-Cr-Co alloy of micron range thickness, also known as the Kaneko alloy. The information about the phase composition is necessary for the development of physical and technical approaches for the production of optimal structures with permanent magnet fi lms on single-crystal silicon wafers, the fi lms being based on a dispersion-hardened alloy with the magnetization vector in the plane of the silicon substrate.
Three-layer metal fi lms were obtained by magnetron sputtering on a silicon wafer: a dispersion-hardened alloy layer based on the Fe-Cr-Co system (3600 nm thick), ), a compensating copper layer (3800 nm), and a vanadium adhesion barrier layer (110 nm). Multilayer fi lms formed on a silicon wafer were subjected to one-minute of annealing in a high vacuum in the temperature range of 600–650 °C. A qualitative phase analysis of the structures obtained by magnetron sputtering and subjected to a single-stage thermal treatment was performed using X-ray diffraction.
It was determined that high-vacuum “rapid” one-minute of annealing of the Fe-Cr-Co dispersion-hardened alloy layer in the temperature range of 600–650 °C does not result in the formation of oxides of the main components or the s-phase. At the temperature of 630 °C, the maximum intensity of the X-ray diffraction line (110) of the a-phase is observed, which indicates the formation of a predominantly a-solid solution and serves as a basis for the correct implementation of the subsequent annealing stages for the spinodal decomposition of this phase.

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