Patent ID: 7186571
Filing Date: 2007-03-06
Classification: H01L

Abstract:
1. A method of fabricating a compositionally modulated electrode in a magnetic tunnel junction device, comprising: depositing a mask layer on a surface of a previously fabricated homogeneous electrode of the magnetic tunnel junction device, the electrode including a first resistivity and overhanging the magnetic tunnel junction device; patterning a plasma mask in the mask layer; forming the plasma mask in the mask layer so that a portion of the surface is exposed by the plasma mask; forming a high resistivity region that extends inward of the surface by exposing the portion of the surface to a plasma process selected from the group consisting of a plasma oxidation process, a plasma nitridation process, and a plasma carburization process, the high resistivity region including a second resistivity that is higher than the first resistivity; and removing the plasma mask from the surface of the electrode to expose a homogeneous electrode having a region of high resistivity adjacent to at least one region of first resistivity.