Method for manufacturing CPP-type magnetoresistance effect element

A method for manufacturing a thin film magnetic head which comprises:

• a magnetoresistance (MR) layered body comprising first and second magnetic layers, at least one of which changes its magnetization direction in response to an external magnetic field, and a nonmagnetic intermediate layer, wherein the first magnetic layer, the nonmagnetic layer and the second magnetic layer are sequentially layered by contacting each other;
• first and second shield layers that function as electrodes for allowing a sense current to flow in a direction orthogonal to the film surface of the MR layered body and are provided in a manner of sandwiching the MR layered body in the direction orthogonal to the film surface of the MR layered body, wherein the first shield layer is provided below in a layering direction and the second shield layer above in the layering direction;
• and
• a bias magnetic layer on the lateral surface of part of the MR layered body for applying a bias magnetic field to the MR layered body,
• the method comprising:
• an MR layered body forming step for forming the MR layered body on the upper surface of the first shield layer;
• a cap layer forming step for forming a first sacrificial layer made of material removable by wet etching above the MR layered body and, subsequently, forming a cap layer on the upper surface of the first sacrificial layer;
• a bias magnetic layer forming step for patterning the MR layered body and the cap layer and then filling part of the removed areas portions of the MR layered body and the cap layer with the bias magnetic layer and the remaining with insulating layers;
• a first sacrificial layer removing step for removing the cap layer by dry etching and, subsequently, removing the first sacrificial layer by wet etching;
• and
• a second shield layer forming step for forming the second shield layer above the MR layered body and the bias magnetic layer.