wherein the first interfacial structure is formed with a metal layer and a capping layer comprising SiN and the second interfacial structure is formed with {TAIL ~ a metal layer} in a same process as {HEAD ~ the metal layer} of the first interfacial structure and a capping layer comprising one of: Co, Ru, Ir, Rh and Pt 
wherein the first interfacial structure is formed with a metal layer and a capping layer comprising SiN and the second interfacial structure is formed with { TAIL ~ a metal layer } in a same process as { HEAD ~ the metal layer } of the first interfacial structure and a capping layer comprising one of : Co , Ru , Ir , Rh and Pt
OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH TAIL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD HEAD OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH