Inverted orthogonal spin transfer layer stack

A memory system comprising:

• a memory cell comprising:
• a pinned magnetic layer having a first fixed magnetization vector with a first fixed magnetization direction;
• a free magnetic layer having a variable magnetization vector having at least a first stable state and a second stable state;
• a first non-magnetic layer spatially separating the pinned magnetic layer and the free magnetic layer;
• a reference magnetic layer having a second fixed magnetization vector with a second fixed magnetization direction;
• and
• a second non-magnetic layer spatially separating the free magnetic layer and the reference magnetic layer, wherein a magnetic tunnel junction is formed by the free magnetic layer, the second non-magnetic layer, and the reference magnetic layer, wherein application of a current pulse, having a selected amplitude and duration, through the magnetic device switches the variable magnetization vector, and wherein the magnetic tunnel junction is spatially located below the pinned magnetic layer;
• and
• a current source connected to the pinned magnetic layer and the reference magnetic layer such that current passes from the second non-magnetic layer to the pinned magnetic layer.

A method of making a memory device, comprising:

• forming a second non-magnetic layer spatially separating a free magnetic layer and a reference magnetic layer, wherein a magnetic tunnel junction is formed by the free magnetic layer, the second non-magnetic layer, and the reference magnetic layer, wherein application of a current pulse, having either positive or negative polarity and a selected amplitude and duration, through the magnetic device switches a variable magnetization vector of the free magnetic layer, and wherein the magnetic tunnel junction is spatially located below the pinned magnetic layer forming the reference magnetic layer having a second fixed magnetization vector with a second fixed magnetization direction;
• forming a first non-magnetic layer spatially separating the pinned magnetic layer and the free magnetic layer;
• forming a free magnetic layer having the variable magnetization vector having at least a first stable state and a second stable state;
• and
• forming a pinned magnetic layer having a first fixed magnetization vector with a first fixed magnetization direction.