Method of manufacturing an integrated circuit
View Patent ↗A method of manufacturing an integrated circuit including a memory device that includes the following processes: forming a mask layer structure above a composite structure including a resistivity changing layer and an electrode layer disposed above the resistivity changing layer; partially patterning the mask layer structure using a first substance; stopping patterning the mask layer structure before exposing the top surface of the electrode layer; at least partially exposing the top surface of the electrode layer using a second substance, the second substance chemically not reacting with the electrode layer material.
1. A method of manufacturing an integrated circuit the method comprising:
forming a mask layer structure above a composite structure, the composite structure comprising a resistivity changing layer and an electrode layer disposed above the resistivity changing layer, the electrode layer having a top surface;
partially patterning the mask layer structure using a first substance;
stopping patterning the mask layer structure before exposing the top surface of the electrode layer; and
at least partially exposing the top surface of the electrode layer using a second substance, the second substance not reacting chemically with an electrode layer material such that clusters of electrode material and second substance are formed.
2. The method according to claim 1 , wherein the first substance comprises a plasma gas.
3. The method according to claim 2 , wherein the first substance comprises a noble plasma gas.
4. The method according to claim 3 , wherein the first substance comprises a fluorine plasma gas.
5. The method according to claim 1 , wherein the second substance comprises a plasma gas.
6. The method according to claim 5 , wherein the second substance comprises a noble plasma gas.
7. The method according to claim 6 , wherein the second substance comprises an argon plasma gas.
8. The method according to claim 1 , wherein the electrode layer comprises metal.
9. The method according to claim 8 , wherein the electrode layer comprises silver.
10. The method according to claim 1 , wherein the resistivity changing layer comprises chalcogenide.
11. The method according to claim 10 , wherein the resistivity changing layer comprises germanium sulphide.
12. The method according to claim 1 , wherein the mask layer structure comprises at least two layers.
13. The method according to claim 12 , wherein the mask layer structure comprises a metal layer and a dielectric layer disposed above the metal layer.
14. The method according to claim 13 , wherein the metal layer comprises titanium nitride or tantalum nitride.
15. The method according to claim 13 , wherein after stopping the patterning of the mask layer structure a remaining portion of the mask layer structure has a thickness of at least 40 percent of an original thickness of the metal layer.
16. The method according to claim 13 , wherein after stopping the patterning of the mask layer structure, a remaining portion of the mask layer structure has a thickness of at least 10 nm.
17. The method according to claim 1 , further comprising patterning the resistivity changing layer using the patterned mask layer structure and the second substance.
18. The method according to claim 17 , wherein the second substance does not significantly chemically react with a resistivity changing layer material.
19. The method according to claim 1 , wherein no chemical substance is formed when the second substance comes into contact with the electrode layer material.
20. A method of patterning a composite structure, the method comprising:
forming a mask layer structure on a composite structure, the composite structure comprising a resistivity changing layer and an electrode layer disposed above the resistivity changing layer;
forming a mask layer over the mask layer structure;
patterning the mask layer using a light exposure process;
patterning the mask layer structure using the patterned mask layer; and
patterning the composite structure using the patterned mask layer structure;
wherein patterning of the mask layer structure comprises:
partially patterning the mask layer structure using a first substance;
stopping patterning the mask layer structure before exposing a top surface of the electrode layer; and
at least partially exposing the top surface of the electrode layer using a second substance, the second substance not reacting chemically with an electrode layer material in a way that clusters of electrode material and second substance are formed.
21. The method according to claim 20 , wherein the first substance comprises a fluorine plasma gas.
22. The method according to claim 20 , wherein the second substance comprises a noble plasma gas.
23. The method according to claim 22 , wherein the second substance comprises an argon plasma gas.
24. The method according to claim 20 , wherein the electrode layer comprises silver.