Perpendicular anisotropy constants and anisotropy energy of oriented cobalt-chromium alloys

Abstract

The magnetic characteristics of sputtered cobalt-chromium films were evaluated over the composition range of 12.8 at percent to 23.5 at percent chromium. The saturation magnetization was greater for sputtered films than for similar bulk alloys at chromium contents greater than about 10 at percent. The second order anisotropy constant, K <inf xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</inf> is only a few percent of the first order anisotropy constant, K <inf xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">1</inf> and therefore, the intrinsic perpendicular anisotropy energy is sufficiently determined by K <inf xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">1</inf> for compositions with Ku>O. The value of K <inf xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">1</inf> decreases with increasing Cr concentration. The anisotropy energy, Ku is negative below a chromium content of 20.5 atomic percent and positive above this value.