Patent ID: 8956883
Filing Date: 2015-02-17
Classification: G11C,H01L

Abstract:
1. A method for fabricating a magnetic tunnel junction, comprising: providing a substrate; forming a first dielectric layer on the substrate; forming a first electrode layer in the first dielectric layer on the substrate; forming a composite magnetic layer on the first electrode layer and the first dielectric layer; forming a first hard mask layer with a first shape on the composite magnetic layer; forming a second mask layer on a surface of the composite magnetic layer and a side surface of the first hard mask layer; removing a portion of the first hard mask layer to form an opening crossing the first hard mask layer; forming a sidewall spacer on side surfaces of the first hard mask layer and the second hard mask layer in the opening; removing the second hard mask layer; and forming a composite magnetic structure having the first shape outer surface and a second shape inner surface by etching through the composite magnetic material layer, wherein the first shape is different from the second shape so as to control thickness between the outer surface and the inner surface.