Magneto-resistance effect element having stack with dual free layer and a plurality of bias magnetic layers

A method of manufacturing a magneto-resistance effect element, comprising:

• a magneto-resistance effect stack forming step of forming a lower magnetic layer whose magnetization direction changes in accordance with an external magnetic field, a non-magnetic intermediate layer, and an upper magnetic layer whose magnetization direction changes in accordance with an external magnetic field, successively upwardly in the order named in a direction of stacking, on a lower shield electrode layer;
• a second bias magnetic layer forming step of removing both sides of said magneto-resistance effect stack in a track width direction, and filling removed spaces with a pair of second bias magnetic layers respectively therein;
• a first bias magnetic layer forming step of forming a recess in a surface opposite to a surface to be formed into an air bearing surface of said magneto-resistance effect stack, wherein said recess extends toward said magneto-resistance effect stack while a width thereof in the track width direction decreases, and filling a portion of said recess with a first bias magnetic layer;
• a magnetization direction securing step of securing magnetization directions of said second bias magnetic layers substantially parallel to said track width direction, such that the magnetic pole on a surface of one of said second bias magnetic layers which faces said magneto-resistance effect stack has the same polarity as the magnetic pole on a surface of the other of said second bias magnetic layers which faces said magneto-resistance effect stack, and has a polarity different from the polarity of the magnetic pole on a surface of said first bias magnetic layer which faces said magneto-resistance effect stack;
• and
• an upper shield electrode layer forming step of forming an upper shield electrode layer on said magneto-resistance effect stack, said first bias magnetic layer, and said second bias magnetic layers.