Pre-oxidation Suppresses Orange-peel Coupling in Magnetic Tunnel Junctions

Orange-peel coupling (OPC) is a common problem when magnetic tunnel junctions (MTJs) are used to detect low magnetic fields. OPC acts as an anisotropy field to reduce the sensitivity of the free layer to small magnetic fields. We have have found that pre-oxidation of the bottom Co electrode in MJTs very effectively suppresses OPC.