Magnesium metallic interlayer as an oxygen-diffusion-barrier between high-κ dielectric thin films and silicon substrate

► HfO2 is prepared by sputtering as a high-κ material. ► We present a method of preventing low-κ interfacial growth. ► The method is based on the pre-deposition of a magnesium metallic interlayer. ► The effect of the post-deposition annealing under nitrogen is also studied.