Perpendicular magnetic memory element having magnesium oxide cap layer

A spin transfer torque magnetic random access memory (STT-MRAM) device comprising a plurality of memory elements, each of said memory elements including a magnetic tunnel junction (MTJ) structure, said MTJ structure comprising:

• a magnetic free layer structure and a magnetic reference layer structure with an insulating tunnel junction layer interposed therebetween;
• a magnetic fixed layer exchange coupled to said magnetic reference layer structure through an anti-ferromagnetic coupling layer;
• a magnesium oxide layer formed adjacent to said magnetic free layer structure opposite said insulating tunnel junction layer;
• and
• a metal layer comprising cobalt and iron formed adjacent to said magnesium oxide layer opposite said magnetic free layer structure,
• wherein said magnetic reference layer structure includes a first magnetic reference layer formed adjacent to said insulating tunnel junction layer and a second magnetic reference layer separated from said first magnetic reference layer by a first perpendicular enhancement layer (PEL), said first and second magnetic reference layers having a first invariable magnetization direction substantially perpendicular to layer planes thereof, said magnetic fixed layer has a second invariable magnetization direction that is substantially perpendicular to a layer plane thereof and is opposite to said first invariable magnetization direction, said magnetic free layer structure includes one or more magnetic free layers having a variable magnetization direction substantially perpendicular to layer planes thereof.