Technique for smoothing an interface between layers of a semiconductor device

A semiconductor memory device, comprising:

• an anti-ferromagnetic layer disposed over a semiconductor substrate;
• a pinned layer having a multiple of films disposed over the anti-ferromagnetic layer;
• a composite layer disposed over the pinned layer, the composite layer having a magnetic material randomly dispersed in a non-magnetic material;
• a barrier layer disposed on the composite layer;
• and
• a free layer disposed over the barrier layer.

A method of fabricating a magnetoresistive random access memory (MRAM) cell, comprising:

• forming a pinning layer over a bottom electrode;
• forming a pinned layer over the pinning layer;
• forming a pre-barrier layer over the pinned layer;
• performing a plasma treatment to the pre-barrier layer;
• thereafter forming a barrier layer over the pre-barrier layer;
• and
• forming a free layer over the barrier layer.