Integrated circuits with magnetic tunnel junctions and methods of producing the same
Integrated circuits and methods of producing the same are provided. In an exemplary embodiment, an integrated circuit includes a magnetic tunnel junction stack. The magnetic tunnel junction stack includes a first free layer that is magnetic, a second free layer that is magnetic, and an insertion layer positioned between the first and second free layers. The insertion layer is non-magnetic, and the insertion layer includes terbium.
1. An integrated circuit comprising a magnetic tunnel junction stack, wherein the magnetic tunnel junction stack comprises:
a total pinned layer that comprises a first pinned layer that is magnetic;
a total free layer that comprises a first free layer that is magnetic;
a tunnel barrier layer positioned between the total pinned layer and the total free layer, wherein the tunnel barrier layer is non-magnetic; and
a transition layer positioned between the total pinned layer and the tunnel barrier layer, wherein the transition layer is non-magnetic, wherein the transition layer comprises terbium at from about 30 to about 100 weight percent, based on a total weight of the transition layer, and wherein the transition layer comprises one or more of iron or cobalt at from about 5 to about 70 weight percent, based on the total weight of the transition layer.
2. The integrated circuit of claim 1 wherein the transition layer comprises the iron at from about 5 to about 70 weight percent, based on the total weight of the transition layer.
3. The integrated circuit of claim 1 wherein the transition layer comprises the cobalt at from about 5 to about 70 weight percent, based on the total weight of the transition layer.
4. The integrated circuit of claim 1 wherein the transition layer is amorphous.
5. The integrated circuit of claim 1 wherein the tunnel barrier layer comprises magnesium oxide.
6. The integrated circuit of claim 1 wherein the magnetic tunnel junction stack further comprises a polarizer layer positioned between the transition layer and the tunnel barrier layer.
7. The integrated circuit of claim 1 wherein:
the total pinned layer further comprises a second pinned layer that is magnetic, wherein the second pinned layer underlies the transition layer; and
a coupling layer positioned between the first pinned layer and the second pinned layer, wherein the coupling layer is non-magnetic.
8. The integrated circuit of claim 7 wherein:
the total free layer further comprises a second free layer that is magnetic, wherein the second free layer overlies the first free layer; and
an insertion layer positioned between the first free layer and the second free layer, wherein the insertion layer is non-magnetic, and wherein the insertion layer comprises terbium.
9. A method of producing an integrated circuit comprising:
forming a total fixed layer that is magnetic;
forming a transition layer overlying the total fixed layer, wherein the transition layer is non-magnetic, wherein the transition layer comprises terbium at from about 30 to about 100 weight percent, based on a total weight of the transition layer, and wherein the transition layer comprises one or more of iron or cobalt at from about 5 to about 70 weight percent, based on the total weight of the transition layer;
forming a tunnel barrier layer overlying the transition layer, wherein the tunnel barrier layer is non-magnetic; and
forming a first free layer overlying the tunnel barrier layer, wherein the first free layer is magnetic.