Thermally stable magnetic elements utilizing spin transfer and an MRAM device using the magnetic element

A magnetic memory device comprising:

• a plurality of magnetic cells including a plurality of magnetic elements, each of the plurality of magnetic elements including a first pinned layer, a first nonmagnetic layer, a second pinned layer, a second nonmagnetic layer, a third pinned layer, a nonmagnetic spacer layer and a free layer, the first pinned layer being ferromagnetic and having a first magnetization pinned in a first direction, the first nonmagnetic layer being conductive and including a first diffusion barrier, the second pinned layer being ferromagnetic and having a second magnetization pinned in a second third direction, the first nonmagnetic layer being between the first pinned layer and the second pinned layer, the second pinned layer being antiferromagnetically coupled with the first pinned layer, the second nonmagnetic layer being conductive and including a second diffusion barrier, the third pinned layer being ferromagnetic and having a third magnetization pinned in a third direction, the second nonmagnetic layer being between the third pinned layer and the second pinned layer, the third pinned layer being antiferromagnetically coupled with the second pinned layer, the free layer being ferromagnetic and having a free layer magnetization, the nonmagnetic spacer layer being conductive, the nonmagnetic spacer layer being between the free layer and the third pinned layer;
• a plurality of row lines coupled to the plurality of magnetic cells;
• and
• a plurality of column lines coupled with the plurality of cells, the plurality of row lines and the plurality of column lines for selecting a portion of the plurality of magnetic cells for reading and writing.

A method for utilizing a magnetic memory comprising the steps of:

• (a) in a write mode, writing to a first portion of a plurality of magnetic cells by driving a write current in a CPP configuration through the a first portion of a plurality of magnetic elements, each of the plurality of magnetic elements including a first pinned layer, a first nonmagnetic layer, a second pinned layer, a second nonmagnetic layer, a third pinned layer, a nonmagnetic spacer layer and a free layer, the first pinned layer being ferromagnetic and having a first magnetization pinned in a first direction, the first nonmagnetic layer being conductive and including a first diffusion barrier, the second pinned layer being ferromagnetic and having a second magnetization pinned in a second third direction, the first nonmagnetic layer being between the first pinned layer and the second pinned layer, the second pinned layer being antiferromagnetically coupled with the first pinned layer, the second nonmagnetic layer being conductive and including a second diffusion barrier, the third pinned layer being ferromagnetic and having a third magnetization pinned in a third direction, the second nonmagnetic layer being between the third pinned layer and the second pinned layer, the third pinned layer being antiferromagnetically coupled with the second pinned layer, the free layer being ferromagnetic and having a free layer magnetization, the nonmagnetic spacer layer being conductive, the nonmagnetic spacer layer being between the free layer and the third pinned layer;
• (b) in a read mode, reading a signal from a second portion of the plurality of cells.

A method for utilizing a magnetic element comprising the steps of:

• (a) in a write mode, driving a write current in a CPP configuration through the magnetic element, the magnetic element including a first pinned layer, a first nonmagnetic layer, a second pinned layer, a second nonmagnetic layer, a third pinned layer, a nonmagnetic spacer layer and a free layer, the first pinned layer being ferromagnetic and having a first magnetization pinned in a first direction, the first nonmagnetic layer being conductive and including a first diffusion barrier, the second pinned layer being ferromagnetic and having a second magnetization pinned in a second third direction, the first nonmagnetic layer being between the first pinned layer and the second pinned layer, the second pinned layer being antiferromagnetically coupled with the first pinned layer, the second nonmagnetic layer being conductive and including a second diffusion barrier, the third pinned layer being ferromagnetic and having a third magnetization pinned in a third direction, the second nonmagnetic layer being between the third pinned layer and the second pinned layer, the third pinned layer being antiferromagnetically coupled with the second pinned layer, the free layer being ferromagnetic and having a free layer magnetization, the nonmagnetic spacer layer being conductive, the nonmagnetic spacer layer being between the free layer and the third pinned layer;
• (b) in a read mode, reading a signal from the magnetic element by driving a read current through the magnetic element in the CPP configuration, the read current being less than the write current.

A method for providing a magnetic element comprising the steps of:

• (a) providing a first pinned layer, the first pinned layer being ferromagnetic and having a first magnetization pinned in a first direction
• (b) providing a first nonmagnetic layer, the first nonmagnetic layer being conductive and including a first diffusion barrier;
• (c) providing a second pinned layer, the second pinned layer being ferromagnetic and having a second magnetization pinned in a second third direction, the first nonmagnetic layer being between the first pinned layer and the second pinned layer, the second pinned layer being antiferromagnetically coupled with the first pinned layer;
• (d) providing a second nonmagnetic layer, the second nonmagnetic layer being conductive and including a second diffusion barrier;
• (e) providing a third pinned layer, the third pinned layer being ferromagnetic and having a third magnetization pinned in a third direction, the second nonmagnetic layer being between the third pinned layer and the second pinned layer, the third pinned layer being antiferromagnetically coupled with the second pinned layer;
• (f) providing a free layer, the free layer being ferromagnetic and having a free layer magnetization;
• and
• (g) providing a nonmagnetic spacer layer, the nonmagnetic spacer layer being conductive, the nonmagnetic spacer layer being between the free layer and the third pinned layer.