We have studied the effects of lowhyphen;temperature sputter preparation and subsequent heat treatment of Co79Cr21thin films with emphasis on their microstructure and magnetic properties. Preparation at minus;196thinsp;deg;C resulted in textured films which did not show the presence of magnetic Cohyphen;rich regions. The saturation magnetization moment,Ms, of these films was similar to their homogeneous alloy phase. Conventionally sputtered films (substrate temperatureroom temperature) had higher values ofMsthan films prepared at minus;196thinsp;deg;C. A 1hyphen;h heat treatment at 500thinsp;deg;C in vacuum reduced theMsof both films. The results suggest rearrangement of atoms through thermal diffusion. For the films sputtered at minus;196thinsp;deg;C (liquidhyphen;nitrogen temperature) an atomistically ordered phase can be proposed based on hexagonal Co which minimizes the presence of nearest Crhyphen;Cr neighbors. This maximizes the moment quenching activity of Cr on Co and reduces the saturation moment over the one of a fully random material for segregated films prepared at higher temperature reductions inMscan also be due to dilution of Co concentration in Cohyphen;rich regions.
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