TUNNEL MAGNETORESISTIVE THIN FILM AND MAGNETIC MULTILAYER FILM FORMATION APPARATUS

摘要

This invention provides a tunnel magnetoresistive thin film which can simultaneously realize a high MR ratio and low magnetostriction. The tunnel magnetoresistive thin film comprises a magnetization fixed layer, a tunnel barrier layer, and a magnetization free layer. The tunnel barrier layer is a magnesium oxide film comprising magnesium oxide crystal grains having (001) orientation. The magnetization free layer has a laminated structure comprising a first magnetization free layer formed of an alloy having (001) orientation having a body centered cubic structure containing a Co atom, an Fe atom, and a B atom or a body centered cubic structure containing a Co atom, an Ni atom, an Fe atom, and a B atom, and a second magnetization free layer formed of an alloy having a face centered cubic structure containing an Fe atom and an Ni atom.