Magnetic and Microstructural Studies On Co-Cr Films Investigated Using NMR

Abstract

ABSTRACTThe compositional distribution of Co-Cr vacuum evaporated films is investigated using the 59Co nuclear magnetic resonance technique. The dependence of the spin-echo spectra of Co-Cr films and powders on Cr concentration is measured. The spectra of the films evaporated at 260°C are found to be similar to those of powder samples with the Cr concentration of approximately 6 at%, although the Cr concentration of the films is between 10 at% and 24 at%. It is concluded that the Cr concentration of the ferromagnetic regions in Co-Cr films remains at 6 at%, although Cr concentration increased to 25 at%. The spin-echo spectra of the films evaporated at 160°C show that the Cr concentration in ferromagnetic regions is slightly higher than that found in the films deposited at 265 °C. This implies that segregation is less developed in the 160°C films The relationship between the magnetic properties and the segregation is also discussed