US Patent 10361361 Thin reference layer for STT MRAM

Techniques relate to forming a magnetic tunnel junction (MTJ). A synthetic antiferromagnetic reference layer is adjacent to a tunnel barrier layer. The synthetic antiferromagnetic reference layer includes a first magnetic layer, a second magnetic layer, and a reference spacer layer sandwiched between the first magnetic layer and the second magnetic layer. A magnetic free layer is adjacent to the tunnel barrier layer so as to be opposite the synthetic antiferromagnetic reference layer. The synthetic antiferromagnetic reference layer has a thickness of at least one of 3 nanometers (nm), 4 nm, and 3-4 nm.