Tunnel magnetoresistive sensor in which at least part of pinned layer is composed of CoFeB layer and method for manufacturing the tunnel magnetoresistive sensor

The present invention particularly relates to a tunnel type magnetic detecting element insulating barrier layer is formed of a Mg-O, to provide the tunnel type magnetic detecting element and its manufacturing method can obtain a high rate of resistance change (ΔR / R) of the. The second fixed magnetic layer (4C), starting from below, with the first magnetic layer (4C1), and the second magnetic layer is formed of CoFe or Fe (4c2) formed of CoFeB or FeB stacking order. On the second fixed magnetic layer (4c), an insulating barrier layer (5) made of Mg-O. By this way the second fixed magnetic layer (4c) of CoFeB or FeB / CoFe or Fe multilayer structure can be obtained a high resistance change rate (ΔR / R).