Memory device

A memory device, comprising:

• a write transistor and a read transistor, formed on a surface region of a substrate;
• a spin-orbit torque layer, lying over the write transistor and the read transistor, and electrically connected with a terminal of the write transistor and a terminal of the read transistor;
• a MTJ, standing on the spin-orbit torque layer and electrically coupled with the spin-orbit torque layer by a first terminal of the MTJ, wherein the MTJ comprises:
• a synthetic free layer comprising a synthetic antiferromagnetic structure, a free layer and a first exchange coupling metal layer between the synthetic antiferromagnetic structure and the free layer, wherein the synthetic antiferromagnetic structure is closer to the spin-orbit torque layer than the free layer;
• a barrier layer disposed over the synthetic free layer;
• and
• a reference layer disposed over the barrier layer;
• and
• a bit line, electrically coupled with a second terminal of the MTJ.

A memory device, comprising:

• a read transistor, formed on a surface region of a substrate, and comprising a read word line extending on the substrate;
• a bit line, lying over the read word line and coupled with a first terminal of the read transistor;
• a spin-orbit torque layer, disposed over the read transistor;
• a MTJ, disposed under the spin-orbit torque layer, wherein the MTJ is electrically coupled with a second terminal of the read transistor by a first terminal of the MTJ and electrically coupled with the spin-orbit torque layer by a second terminal of the MTJ, and the MTJ comprises:
• a synthetic free layer comprising a synthetic antiferromagnetic structure, a free layer and a first exchange coupling metal layer between the synthetic antiferromagnetic structure and the free layer, wherein the synthetic antiferromagnetic structure is disposed between the spin-orbit torque layer and the first exchange coupling metal layer;
• a barrier layer disposed under the synthetic free layer;
• and
• a reference layer disposed under the barrier layer;
• a selector, disposed over the spin-orbit torque layer and electrically coupled with the spin-orbit torque layer by a first terminal of the selector;
• and
• a write word line, lying over the selector and electrically coupled with a second terminal of the selector.