Methods for manufacturing magnetic memory devices
Disclosed is a method for manufacturing a magnetic memory device. The method for manufacturing a magnetic memory device comprises sequentially forming a first magnetic layer, a tunnel barrier layer, and a second magnetic layer on a substrate, forming a boron absorption layer on the second magnetic layer, sequentially forming a metal capping layer and an oxygen donor layer on the boron absorption layer, and performing a heat treatment process to diffuse at least a portion of oxygen atoms included in the oxygen donor layer into the metal capping layer and the boron absorption layer. The metal capping layer has a greater oxygen diffusivity than the oxygen donor layer.
1. A method for manufacturing a magnetic memory device, the method comprising:
sequentially forming a first magnetic layer, a tunnel barrier layer, and a second magnetic layer on a substrate;
forming a boron absorption layer on the second magnetic layer;
sequentially forming a metal capping layer and an oxygen donor layer on the boron absorption layer, the metal capping layer having a greater oxygen diffusivity than the oxygen donor layer; and
performing a heat treatment process to diffuse at least a portion of oxygen atoms contained in the oxygen donor layer into the metal capping layer and the boron absorption layer.
2. The method of claim 1 , wherein at least a portion of boron atoms contained in the second magnetic layer diffuse into the boron absorption layer as a result of the heat treatment process.
3. The method of claim 1 , further comprising an additional heat treatment process, wherein the additional heat treatment process is performed before forming the metal capping layer and the oxygen donor layer,
wherein at least a portion of boron atoms, contained in the second magnetic layer, diffuse into the boron absorption layer as a result of the additional heat treatment process.
4. The method of claim 1 , wherein the metal capping layer comprises at least one of magnesium, aluminum, scandium, titanium, vanadium, chromium, manganese, niobium, tungsten, and tantalum.
5. The method of claim 1 , wherein the oxygen donor layer is formed directly on the metal capping layer using a radio frequency (RF) sputtering process, and
wherein the oxygen donor layer comprises at least one of magnesium oxide, aluminum oxide, titanium oxide, vanadium oxide, tungsten oxide, tantalum oxide, hafnium oxide, zirconium oxide, platinum oxide, iridium oxide, ruthenium oxide, lead oxide, palladium oxide, osmium oxide, rhodium oxide, and rhenium oxide.
6. The method of claim 1 , wherein forming the oxygen donor layer comprises:
forming a metal layer on the metal capping layer; and
oxidizing the metal layer,
wherein the metal layer comprises at least one of platinum, iridium, ruthenium, lead, palladium, osmium, rhodium, and rhenium.
7. The method of claim 1 , wherein the boron absorption layer comprises at least one of titanium, hafnium, zirconium, and tantalum.
8. The method of claim 1 , wherein the metal capping layer and the boron absorption layer are oxidized as a result the heat treatment process to provide an oxidized metal capping layer and an oxidized boron absorption layer,
wherein the oxidized metal capping layer comprises metal oxide having a non-stoichiometric composition ratio, and the oxidized boron absorption layer comprises metal boron oxide having a non-stoichiometric composition ratio.
9. The method of claim 1 , wherein the metal capping layer and/or the oxygen donor layer has a thickness in a range from about 0.5 Å to about 10 Å.
10. The method of claim 1 , further comprising removing the oxygen donor layer and the metal capping layer after performing the heat treatment process.
11. The method of claim 1 , further comprising sequentially and alternately forming at least one additional metal capping layer and at least one additional oxygen donor layer on the oxygen donor layer, before performing the heat treatment process.
12. A method for manufacturing a magnetic memory device, the method comprising:
sequentially forming an oxygen donor layer and a metal capping layer on a substrate, the metal capping layer including a greater oxygen diffusivity than the oxygen donor layer;
forming a boron absorption layer on the metal capping layer;
sequentially forming a first magnetic layer, a tunnel barrier layer, and a second magnetic layer on the boron absorption layer; and
performing a heat treatment process to diffuse at least a portion of oxygen atoms contained in the oxygen donor layer into the metal capping layer and the boron absorption layer and to diffuse at least a portion of boron atoms contained in the first magnetic layer into the boron absorption layer.
13. The method of claim 12 , wherein the metal capping layer comprises at least one of magnesium, aluminum, scandium, titanium, vanadium, chromium, manganese, niobium, tungsten, and tantalum.
14. The method of claim 12 , wherein the oxygen donor layer is formed directly on the substrate using a radio frequency (RF) sputtering process,
wherein the oxygen donor layer comprises at least one of magnesium oxide, aluminum oxide, titanium oxide, vanadium oxide, tungsten oxide, tantalum oxide, hafnium oxide, zirconium oxide, platinum oxide, iridium oxide, ruthenium oxide, lead oxide, palladium oxide, osmium oxide, rhodium oxide, and rhenium oxide.
15. The method of claim 12 , wherein forming the oxygen donor layer comprises:
forming a metal layer on the substrate; and
oxidizing the metal layer,
wherein the metal layer comprises at least one of platinum, iridium, ruthenium, lead, palladium, osmium, rhodium, and rhenium.
16. The method of claim 12 , wherein the boron absorption layer comprises at least one of titanium, hafnium, zirconium, and tantalum.
17. The method of claim 12 , wherein the metal capping layer and the boron absorption layer are oxidized as a result of the heat treatment process to provide an oxidized metal capping layer and an oxidized boron absorption layer,
wherein the oxidized metal capping layer comprises metal oxide having a non-stoichiometric composition ratio, and the oxidized boron absorption layer comprises metal boron oxide having a non-stoichiometric composition ratio.
18. A method for manufacturing a magnetic tunnel junction for a magnetic memory device, the method comprising:
forming an interlayer dielectric layer on a substrate;
forming at least one contact plug to penetrate the interlayer dielectric layer;
sequentially forming a first magnetic layer, a tunnel barrier layer, and a second magnetic layer on the interlayer dielectric layer and the at least one contact plug;
forming a boron absorption layer on the second magnetic layer;
sequentially forming a metal capping layer and an oxygen donor layer on the boron absorption layer, the metal capping layer having a greater oxygen diffusivity than the oxygen donor layer; and
performing a heat treatment process to diffuse at least a portion of oxygen atoms contained in the oxygen donor layer into the metal capping layer and the boron absorption layer.
19. The method of claim 18 , wherein at least a portion of boron atoms contained in the second magnetic layer diffuse into the boron absorption layer as a result of the heat treatment process.
20. The method of claim 18 , further comprising an additional heat treatment process, wherein the additional heat treatment process is performed before forming the metal capping layer and the oxygen donor layer,
wherein at least a portion of boron atoms, contained in the second magnetic layer, diffuse into the boron absorption layer as a result of the additional heat treatment process.