Integrated circuits with magnetic tunnel junctions and methods for producing the same

A method of producing an integrated circuit comprising:

• forming a fixed layer overlying a substrate, wherein the fixed layer comprises a magnetic material;
• forming a first tunnel barrier layer overlying the fixed layer, wherein the first tunnel barrier layer is non-magnetic;
• forming a total free layer overlying the first tunnel barrier layer, wherein the total free layer comprises a first free layer, a first spacer layer overlying the first free layer, and a second free layer overlying the first spacer layer, wherein the first free layer comprises cobalt, iron, and boron, the second free layer comprises cobalt, iron, and boron, and the first spacer layer is non-magnetic;
• forming a second tunnel barrier layer overlying the total free layer, wherein the second tunnel barrier layer comprises magnesium oxide and a second tunnel barrier boron sink material, wherein a boride formation enthalpy of the second tunnel barrier boron sink material is lower than the boride formation enthalpy of cobalt;
• and
• annealing the integrated circuit, wherein a boron concentration in the second free layer decreases during the anneal and a boride concentration in the second tunnel barrier layer increases during the anneal.