主权项 |
1. A method of manufacturing a magnetoresistive device, the magnetoresistive device including: a first electrode and a second electrode located at a distance from each other; a magnetoresistive element including a metal layer and disposed between the first electrode and the second electrode; and an insulating portion in contact with the magnetoresistive element, wherein
the magnetoresistive element has a first surface in contact with the first electrode, a second surface in contact with the second electrode, and a third surface connecting the first and second surfaces to each other, the metal layer includes the second surface, and the insulating portion is made of magnesium oxide, the method comprising the steps of: forming the first electrode; forming a magnetoresistive film on the first electrode, the magnetoresistive film becoming the magnetoresistive element later and having a top surface including a pre-second-surface-portion that later becomes the second surface; patterning the magnetoresistive film so that the magnetoresistive film is provided with at least part of the third surface; forming the insulating portion from magnesium oxide such that the insulating portion is in contact with the at least part of the third surface; removing an unwanted magnesium oxide film that has been formed on the pre-second-surface portion by the magnesium oxide in the step of forming the insulating portion; and forming the second electrode after the step of removing the unwanted magnesium oxide film, wherein in the step of removing the unwanted magnesium oxide film, the unwanted magnesium oxide film is wet etched by using an etchant containing an aqueous ammonia solution. |