Benefit of inserting a (Cu/Pt) intermixing dual barrier for the blocking temperature distribution of exchange biased Co/(Cu/Pt)/IrMn stacks

Abstract : Exchange bias based spintronics devices involve ferromagnetic/antiferromagnetic interfaces and concomitant layers intermixing. As a consequence, interfacial spin-glass-like phases with reduced properties and increased dispersions form and lower the device performance. It is therefore necessary to limit intermixing by introduction of diffusion barriers. One of the major difficulties is that the barrier must be inert. This paper uses blocking temperature distributions to quantify the interfacial quality of Co/IrMn based stacks. Inserting a (Cu/Pt) dual barrier fulfils the manifold requirements of limiting Co-Mn, Co-Pt, and Cu-Mn intermixing, which takes place when using either no or single Pt and Cu barriers, respectively.