A memory and method of making a memory is disclosed. In one embodiment,
the memory includes a cap structure for a magnetoresistive random access
memory device including an etch stop layer formed over an upper magnetic
layer of a magnetoresistive junction (MTJ/MCJ) layered structure and a
hardmask layer formed over said etch stop layer, wherein said etch stop
layer is selected from a material such that an etch chemistry used for
removing said hardmask layer has selectivity against etching said etch
stop layer material. In a method of opening the hardmask layer, an etch
process to remove exposed portions of the hardmask layer is implemented,
where the etch process terminates on the etch stop layer.