A seed layer stack (24) with a smooth top surface having a peak to peak roughness of 0.5 nm is formed by sputter depositing an amorphous layer (22) on a seed layer (21) such as Mg where the seed layer has a resputtering rate 2 to 30X that of the amorphous layer. The uppermost seed layer (23) is a template layer that is NiCr or NiFeCr. 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 amorphous seed layer is SiN, TaN, or CoFeM where M is B or another element with a content that makes CoFeM amorphous as deposited. The seed layer stack may include a bottommost Ta or TaN buffer layer.