A semiconductor structure and fabrication method of forming a semiconductor structure. The method first provides an electrically conductive structure embedded in an interconnect dielectric material layer of a magnetoresistive random access memory device. A conductive landing pad is located on a surface of the electrically conductive structure. A multilayered magnetic tunnel junction (MTJ) structure and an MTJ cap layer is formed on the landing pad. Then there is formed a first conductive layer on top the MTJ cap layer and a second conductive metal layer formed on top the first conductive layer. A pillar mask structure is then patterned and formed on the second conductive layer. The resulting structure is subject to lithographic patterning and etching to form a patterned bilayer metal hardmask pillar structure on top the MTJ cap layer. Subsequent etch processing forms an MTJ stack having sidewalls aligned to the patterned bilayer metal hardmask pillar.