Patent ID: 10522747

Abstract:
A laminated seed layer stack with a smooth top surface having a peak to peak roughness of 0.5 nm is formed by sequentially sputter depositing a first seed layer, a first amorphous layer, a second seed layer, and a second amorphous layer where each seed layer may be Mg and has a resputtering rate 2 to 30X that of the amorphous layers that are TaN, SiN, or a CoFeM alloy. A template layer that is NiCr or NiFeCr is formed on the second amorphous layer. As a result, perpendicular magnetic anisotropy in an overlying magnetic layer that is a reference layer, free layer, or dipole layer is substantially maintained during high temperature processing up to 400° C. and is advantageous for magnetic tunnel junctions in embedded MRAMs, spintronic devices, or in read head sensors. The laminated seed layer stack may include a bottommost Ta or TaN buffer layer.