Embodiments of the disclosure provide methods for forming MTJ structures from a film stack disposed on a substrate for MRAM applications and associated MTJ devices. The methods described herein include forming the film properties of material layers from the film stack to create a film stack with a sufficiently high perpendicular magnetic anisotropy (PMA). An iron containing oxide capping layer is utilized to generate the desirable PMA. By utilizing an iron containing oxide capping layer, thickness of the capping layer can be more finely controlled and reliance on boron at the interface of the magnetic storage layer and the capping layer is reduced.