MRAM and STT-MRAM employ a p-MTJ cell as a switching and storage device. P-MTJs have a general structure wherein an insulating tunnel barrier layer is sandwiched between two magnetic layers. One of the magnetic layers is called the pinned layer and has a magnetization fixed in an out-of-plane direction in the (+z) direction, for example, when the plane of the magnetic layer is formed along the x-axis and y-axis directions. The pinned layer may have a synthetic antiparallel (SyAP) configuration in which an inner magnetic (AP1) layer adjoining the tunnel barrier layer is antiferromagnetically coupled with an outer magnetic (AP2) layer through an intermediate antiferromagnetic coupling (AFC) layer such as Ru. The second magnetic layer called the free layer also has an out-of-plane magnetization with a direction that is free to be either parallel in a (+z) direction (P state) or antiparallel in a (?z) direction (AP state) to that of the AP1 layer. The difference in resistance between the P state (R_P) and AP state (R_AP) can be characterized by the equation (R_AP?R_P)/R_P that is also known as DRR or the magnetoresistive (MR) ratio. It is important for p-MTJ devices to have a large DRR value since this property is directly related to the read margin for the memory bit, or the ease of differentiating between the P state and AP state (0 or 1 bits).