Magnetic memory cells with low switching current density

A method of operating a memory cell comprising:

• providing a memory cell comprising
• a substrate defined with a memory cell region,
• a cell selector unit defined on the substrate, wherein the cell selector unit comprises at least one select transistor,
• a storage element which comprises a magnetic tunnel junction (MTJ) element coupled to the selector unit, wherein the MTJ element comprises a free layer, a fixed layer and a tunnel barrier sandwiched between the fixed and free layers,
• a spin-orbit-torque (SOT) layer coupled to the selector unit and is in direct contact with the free layer, and
• a strain induced layer coupled to a digital line (DL) and in direct contact with the SOT layer;
• and
• performing a read operation or write operation with the memory cell, wherein when a write operation is performed, a write path is formed through the SOT layer and the DL is activated, an electric field to applied to the strain induced layer induces a strain on the SOT layer which reduces magnetic anisotropy of the free layer that is in direct contact with the SOT layer.

A method of forming a memory cell comprising:

• providing a substrate defined with a memory cell region;
• forming a cell selector unit on the substrate, wherein forming the cell selector unit comprises forming at least one select transistor;
• forming a storage element which comprises a magnetic tunnel junction (MTJ) element coupled to the selector unit, wherein the MTJ element comprises a free layer, a fixed layer and a tunnel barrier sandwiched between the fixed and free layers;
• forming a spin-orbit-torque (SOT) layer and coupling the SOT layer to the selector unit, wherein the SOT layer is formed below and in direct contact with the free layer;
• and
• forming a strain induced layer and coupling the strain induced layer to a digital line (DL) and in direct contact with the SOT layer, wherein when the DL is activated, an electric field applied to the strain induced layer induces a strain on the SOT layer.