Magnetic read sensor with SDT tri-layer and method for making same

[[abstract]]An Spin Dependent Tumelina SDT read sensor includes a first ferromagnetic (FM) layer and a second FM layer separated by an insulating layer. The first FM layer and second FM layer are substantially electrically isolated from each other. Specifically, the sidewalls of the SDT read sensor are substantially free of electrical paths between the first FM layer and the second FM layer. Also, a surface of the second FM layer that is substantially parallel to the air bearing surface, is recessed from the air bearing surface. A method for forming an SDT read sensor includes depositing a first FM material layer, depositing an intermediate insulation material layer over the first FM material layer, and then depositing a second FM material layer over the intermediate insulation material layer. The second FM material layer and the intermediate insulation material layer are etched, with the etching being stopped before the etching etches the first FM material layer.[[fileno]]2020314060007[[department]]材料科學工程學