Patent ID: 7352021

Claim:
A magnetic tunnel junction structure for a magnetic random access memory comprising: a lower electrode that comprises a Ti-rich TiN layer having a titanium (Ti) content of between about 70 and about 90 atomic percent, the Ti-rich TiN layer having a lower chemical mechanical polishing rate than a stoichiometric TiN layer and having a surface roughness that is also lower than a stoichiometric TiN layer; an oxide layer on the lower electrode; and a magnetic tunnel junction on the oxide layer, the magnetic tunnel junction comprising: a fixed layer including a seed layer; a tunneling barrier on the seed layer, that is oriented in a same crystalline direction as a most closely packed plane direction of the seed layer, the surface roughness of the tunneling barrier being reduced by the lower surface roughness of the Ti-rich TiN layer; and a free layer on the tunneling barrier.