Magnetic memory device and method for manufacturing the same

A memory device comprising:

• a magnetic tunnel junction including:
• a first free layer;
• a pinned layer;
• and a tunnel barrier layer between the first free layer and the pinned layer, wherein
• the first free layer includes a first free magnetic pattern adjacent to the tunnel barrier layer and a second free magnetic pattern spaced apart from the tunnel barrier layer with the first free magnetic pattern therebetween,
• the second free magnetic pattern contacts the first free magnetic pattern,
• the first and second free magnetic patterns include boron (B),
• a boron content of the first free magnetic pattern is higher than a boron content of the second free magnetic pattern,
• the boron content of the first free magnetic pattern is in a range of about 25 at % to about 50 at %, and
• the pinned layer includes a first pinned layer adjacent to the tunnel barrier layer, the first pinned layer including,
• a polarization enhancement magnetic pattern adjacent to the tunnel barrier layer;
• and
• a middle magnetic pattern spaced apart from the tunnel barrier layer with the polarization enhancement magnetic pattern therebetween, the middle magnetic pattern contacting the polarization enhancement magnetic pattern, and the middle portion having a boron content higher than a boron content of the polarization enhancement magnetic pattern and a boron content of the second pinned layer.