Memory cells, semiconductor devices including such cells, and methods of fabrication
Memory cells are disclosed, which cells include a cell material and an ion-source material over the cell material. A discontinuous interfacial material is included between the cell material and the ion-source material. Also disclosed are fabrication methods and semiconductor devices including the disclosed memory cells.
1. A memory cell comprising:
a cell material;
an ion-source material over the cell material, the ion-source material comprising atoms; and
a discontinuous interfacial material between the cell material and the ion-source material, the discontinuous interfacial material comprising interfacial complexes occupying less than all reaction surface sites of the cell material.
2. The memory cell of claim 1 , wherein each interfacial complex comprises an adherent atom and at least one of the atoms of the ion-source material.
3. The memory cell of claim 1 , wherein the interfacial complexes occupy less than 60% of a surface area defined by the cell material.
4. The memory cell of claim 1 , wherein the interfacial complexes are spaced apart from one another.
5. The memory cell of claim 1 , wherein each interfacial complex is spaced from another interfacial complex by a distance greater than 290 picometers.
6. The memory cell of claim 2 , wherein the adherent atoms comprise atoms selected from the group consisting of aluminum, titanium, zirconium, hafnium, vanadium, niobium, tantalum, chromium, molybdenum, tungsten, germanium, tellurium, cobalt, silicon, sulfur, carbon, oxygen, and nitrogen.
7. The memory cell of claim 1 , wherein the discontinuous interfacial material is in direct contact with the cell material and the ion-source material.
8. The memory cell of claim 1 , wherein the ion-source material comprises at least one of copper and silver.
9. A method of forming a memory cell, the method comprising:
exposing a cell material to an adhesion-promoter compound comprising an adherent atom and at least one ligand bonded to the adherent atom;
chemisorbing the adhesion-promoter compound to the cell material to form reactive sites, each reactive site comprising the adherent atom, the adherent atom of one reactive site spaced from the adherent atom of another reactive site by a distance equal to or greater than a width of the at least one ligand; and
forming an ion-source material over the reactive sites and the cell material to form a discontinuous interfacial material between the cell material and the ion-source material, the discontinuous interfacial material comprising interfacial complexes occupying less than all reaction surface sites of the cell material.
10. The method of claim 9 , wherein forming an ion-source material over the reactive sites and the cell material comprises exposing the reactive sites to a precursor of an ion-source material to form the discontinuous interfacial material.
11. The method of claim 10 , wherein exposing the reactive sites to a precursor of an ion-source material comprises forming interfacial complexes between the cell material and the ion-source material, each interfacial complex comprising the adherent atom and at least one atom from the precursor of the ion-source material.
12. The method of claim 10 , wherein exposing the reactive sites to a precursor of an ion-source material comprises bonding at least one metal atom from the precursor of the ion-source material to the adherent atom of the adhesion-promoter compound.
13. The method of claim 9 , wherein chemisorbing the adhesion-promoter compound to the cell material to form reactive sites comprises bonding the adherent atom to the cell material.
14. The method of claim 9 , wherein chemisorbing the adhesion-promoter compound to the cell material to form reactive sites comprises forming an at least partial monolayer of adhesion-promoter compound on the cell material.
15. The method of claim 9 , wherein exposing a cell material to an adhesion-promoter compound comprises forming a discontinuous metal material over a portion of the cell material.
16. The method of claim 9 , wherein exposing a cell material to an adhesion-promoter compound comprises exposing the cell material to an adhesion-promoter compound comprising a metal adherent atom and at least one hydrocarbon group bonded to the metal adherent atom.
17. The method of claim 9 , wherein exposing a cell material to an adhesion-promoter compound comprises exposing the cell material to an adhesion-promoter compound comprising an aluminum adherent atom and three methyl groups bonded to the aluminum adherent atom.
18. The method of claim 9 , wherein exposing a cell material to an adhesion-promoter compound comprises exposing the cell material to an adhesion-promoter compound comprising a metal adherent atom and at least one alkoxide group bonded to the metal adherent atom.
19. The method of claim 9 , further comprising removing the at least one ligand before forming the ion-source material over the reactive sites.
20. A method comprising:
applying a voltage to a semiconductor device comprising a cell material over a first electrode, an ion-permeable material over the cell material, an ion-source material over the ion-permeable material and over the cell material, and a second electrode over the ion-source material, the ion-permeable material comprising interfacial complexes comprising adherent atoms each chemisorbed to the cell material and bonded to at least one atom within the ion-source material; and
drifting atoms through the ion-permeable material.
21. The method of claim 20 , wherein drifting atoms through the ion-permeable material comprises forming a conductive pathway electroconductively connecting the first electrode and the second electrode.
22. The method of claim 20 , wherein drifting atoms through the ion-permeable material comprises drifting metal atoms between the adherent atoms of the interfacial complexes.
23. A semiconductor device, comprising:
at least one memory cell comprising:
a cell material;
an ion-source material over the cell material; and
an ion-permeable material between the cell material and the ion-source material, the ion-permeable material comprising:
adherent atoms each chemisorbed to the cell material and bonded to at least one atom within the ion-source material.
24. The semiconductor device of claim 23 , wherein the at least one atom within the ion-source material comprises at least one of copper and silver.
25. The semiconductor device of claim 23 , wherein the ion-permeable material is permeable to at least one of copper ions and silver ions.
26. The semiconductor device of claim 23 , wherein the adherent atoms occupy less than or equal to about 60 percent of a surface area defined by the cell material.
27. The semiconductor device of claim 23 , wherein the ion-permeable material comprises a partial monolayer of the adherent atoms.