A MgO layer is formed using a process flow wherein a Mg layer is deposited at a temperature 10−6 Torr is reached and a substantial portion of the Mg layer sublimes and leaves a Mg monolayer. After an oxidation between −223° C. and 900° C., a MgO monolayer is produced where the Mg:O ratio is exactly 1:1 thereby avoiding underoxidized or overoxidized states associated with film defects. The process flow may be repeated one or more times to yield a desired thickness and resistance×area value when the MgO is a tunnel barrier or Hk enhancing layer. Moreover, a doping element (M) may be added during Mg deposition to modify the conductivity and band structure in the resulting MgMO layer.