Patent ID: 8119018

Claim:
A magnetoresistive effect element manufacturing method comprising: a first step of preparing a magnetoresistive effect element including a magnetic film and a substrate; a second step of etching a predetermined region of the magnetic film by a reactive ion etching method in the presence of a hydrogen atom and an oxygen atom activated by a plasma; and a third step of exposing the magnetic film having undergone the second step to a plasma at an ion current density of not more than 4×10 −7 A/cm 2 , wherein the third step comprises a plasma formation step of forming a plasma by supplying a reducing gas, a removal step of removing ions and electrons from the plasma formed in the plasma formation step by passing the plasma through a first member having a plurality of through holes, wherein the first member is set at a ground potential, and an exposure step of exposing the magnetic film to a plasma which is adjusted to the ion current density through the removal step and mainly contains a radical, thereby reducing the oxygen atom coupled to the magnetic film.