Spin-transfer torque magnetic random access memory with perpendicular magnetic anisotropy multilayers

A spin transfer torque magnetic random access memory (STTMRAM) element comprising:

• a composite free layer including one or more repeats of a bilayer unit that comprises an insulator layer and a magnetic layer, said magnetic layer having a variable magnetization direction substantially perpendicular to a layer plane thereof;
• a magnetic pinned layer having a first fixed magnetization direction substantially perpendicular to a layer plane thereof;
• a tunnel barrier layer formed between said composite free layer and said magnetic pinned layer;
• and
• a magnetic fixed layer coupled to said magnetic pinned layer through an anti-ferromagnetic coupling layer, said magnetic fixed layer having a second fixed magnetization direction that is substantially perpendicular to a layer plane thereof and is substantially opposite to said first fixed magnetization direction.