Method of forming magnetic patterns, and method of manufacturing magnetic memory devices
A composition for cleaning a magnetic pattern, a method of manufacturing a magnetic memory device, a method of forming a magnetic pattern, and a magnetic memory device, the composition including a glycol ether-based organic solvent; a decomposing agent that includes an aliphatic amine; and at least one of a chelating agent, or a cleaning accelerator that includes an organic alkaline compound, wherein the composition is devoid of water.
1. A method of manufacturing a magnetic memory device, the method comprising:
forming a first magnetic layer, a tunnel barrier layer, a second magnetic layer, and a metal mask sequentially on a substrate;
forming a magnetic tunnel junction (MTJ) structure by etching the second magnetic layer, the tunnel barrier layer, and the first magnetic layer using the metal mask; and
removing an etching residue from a sidewall of the MTJ structure using a cleaning composition that is devoid of water, wherein the cleaning composition includes:
a glycol ether-based organic solvent,
a decomposing agent that includes an aliphatic amine, and
at least one of:
a chelating agent, or
a cleaning accelerator that includes an organic alkaline compound,
wherein the etching residue includes a metal complex formed from a combination of at least two metal species,
wherein removing the etching residue includes separating the metal complex into assemblies by the decomposing agent, each of the assemblies including an individual metal of the metal species, and
wherein the metal complex includes at least one of tungsten-titanium-cobalt, tungsten-titanium-cobalt-iron, or tungsten-titanium-ruthenium-cobalt.
2. The method as claimed in claim 1 , wherein:
the metal mask includes tungsten,
the tunnel barrier layer includes a metal oxide, and
the first magnetic layer and the second magnetic layer each independently include a ferromagnetic metal or a ferromagnetic alloy.
3. The method as claimed in claim 1 , further comprising forming a lower barrier conductive layer between the substrate and the first magnetic layer.
4. The method as claimed in claim 3 , further comprising forming an upper barrier conductive layer between the second magnetic layer and the metal mask.
5. The method as claimed in claim 4 , further comprising forming a spacer layer under the upper barrier conductive layer such that the spacer layer includes an anti-ferromagnetic metal.
6. The method as claimed in claim 5 , further comprising forming a magnetic pattern on the substrate by performing an etching process using the metal mask, wherein the magnetic pattern includes a lower barrier conductive pattern, the MTJ structure, a spacer, an upper barrier conductive pattern, and the metal mask.
7. The method as claimed in claim 1 , wherein a surface of the metal mask is passivated by the chelating agent.
8. The method as claimed in claim 1 , wherein:
the organic solvent includes at least one of diethylene glycol monomethyl ether or dipropylene glycol monomethyl ether,
the decomposing agent includes at least one of a primary amine or an alkanol amine,
the cleaning accelerator includes a quaternary ammonium hydroxide, and
the chelating agent includes ethylenediamine tetraacetic acid.
9. The method as claimed in claim 1 , wherein the cleaning composition includes:
about 50 weight percent to about 95 weight percent of the organic solvent;
about 4 weight percent to about 45 weight percent of the decomposing agent;
about 0.001 weight percent to about 5 weight percent of the cleaning accelerator; and
about 0.001 weight percent to about 5 weight percent of the chelating agent, all weight percent being based on a total weight of the composition.
10. The method as claimed in claim 1 , wherein the tunnel barrier layer includes magnesium oxide or aluminum oxide.
11. The method as claimed in claim 1 , further comprising performing a rinsing process using an alcohol-based rinse solution after removing the etching residue.
12. The method as claimed in claim 1 , wherein the tunnel barrier layer includes magnesium oxide or aluminum oxide.
13. A method of forming a magnetic pattern, the method comprising:
forming a layer stack structure such that the layer stack structure includes at least one magnetic layer, at least one metal oxide layer, and at least one metal layer;
etching the layer stack structure to form a magnetic pattern;
removing a metallic etching residue from a sidewall of the magnetic pattern using a cleaning composition that is devoid of water, wherein the cleaning composition includes:
a glycol ether-based organic solvent,
a decomposing agent that includes an aliphatic amine, and
at least one of:
a chelating agent, or
a cleaning accelerator that includes an organic alkaline compound, and
rinsing a residue of the metallic etching residue or the cleaning composition using an alcohol-based rinse solution.
14. The method as claimed in claim 13 , wherein the cleaning composition includes:
about 50 weight percent to about 95 weight percent of the glycol ether-based organic solvent;
about 4 weight percent to about 45 weight percent of the decomposing agent;
about 0.001 weight percent to about 5 weight percent of the cleaning accelerator; and
about 0.001 weight percent to about 5 weight percent of the chelating agent, all weight percent being based on a total weight of the composition.
15. A method of manufacturing a magnetic memory device, the method comprising:
providing a substrate;
sequentially forming a first magnetic layer, a tunnel barrier layer, a second magnetic layer, and a metal mask on the substrate;
forming a magnetic tunnel junction (MTJ) structure by etching the second magnetic layer, the tunnel barrier layer, and the first magnetic layer using the metal mask; and
removing an etching residue from a sidewall of the MTJ structure using a cleaning composition, wherein the cleaning composition has a pH of about 9 to about 12.5 and includes:
a glycol ether-based organic solvent,
a decomposing agent that includes an aliphatic amine, and
at least one of:
a chelating agent, or
a cleaning accelerator that includes an organic alkaline compound.
16. The method as claimed in claim 15 , wherein the decomposing agent includes at least one of a primary amine or an alkanol amine.
17. The method as claimed in claim 15 , wherein:
the composition includes the cleaning accelerator, and
the cleaning accelerator includes a quaternary ammonium hydroxide.
18. The method as claimed in claim 15 , wherein:
the composition includes the chelating agent, and
the chelating agent includes a compound that forms a coordination bond with a metal.
19. A magnetic memory device prepared according to the method as claimed in claim 15 .
20. The method as claimed in claim 15 , wherein the cleaning composition includes:
about 50 weight percent to about 95 weight percent of the glycol ether-based organic solvent;
about 4 weight percent to about 45 weight percent of the decomposing agent;
about 0.001 weight percent to about 5 weight percent of the cleaning accelerator; and
about 0.001 weight percent to about 5 weight percent of the chelating agent, all weight percent being based on a total weight of the composition.