Method of polishing a multi-layer substrate
View Patent ↗The invention provides a method for polishing one or more layers of a multi-layer substrate that includes a first metal layer and a second layer comprising (i) contacting the first metal layer with a polishing system comprising a liquid carrier, at least one oxidizing agent, at least one polishing additive that increases the rate at which the system polishes at least one layer of the substrate, at least one stopping compound with a polishing selectivity of the first metal layer:second layer of at least about 30:1, wherein the stopping compound is a cationically charged nitrogen containing compound selected from compounds comprising amines, imines, amides, imides, and mixtures thereof, and a polishing pad and/or an abrasive, and (ii) polishing the first metal layer with the system until at least a portion of the first metal layer is removed from the substrate.
1. A method for polishing one or more layers of a multi-layer substrate that includes a first metal layer and a second layer comprising:
(i) contacting the first metal layer with a polishing system comprising:
(a) a liquid carrier,
(b) at least one oxidizing agent,
(c) at least one carboxylic acid that increases the rate at which the system polishes at least one layer of the substrate,
(d) polyethylenimine,
(e) a polishing pad and/or an abrasive, and
(ii) polishing the first metal layer with the system until at least a portion of the first metal layer is removed from the substrate.
2. The method of claim 1 , wherein the liquid carrier is a nonaqueous solvent.
3. The method of claim 1 , wherein the liquid carrier is water.
4. The method of claim 3 , wherein the system comprises an abrasive, and the abrasive is suspended in the liquid carrier.
5. The method of claim 3 , wherein the system comprises an abrasive, and the abrasive is fixed on the polishing pad.
6. The method of claim 3 , wherein no abrasive is present in the system, and the polishing pad is not an abrasive-containing pad.
7. The method of claim 3 , wherein the polyethlenimine present in the liquid carrier in a concentration of about 5 wt. % or less.
8. The method of claim 3 , wherein at least one carboxylic acid is selected from the group consisting of di-carboxylic acids, tri-carboxylic acids, poly-carboxylic acids, and mixtures thereof.
9. The method of claim 8 , wherein at least one oxidizing agent is a peroxide, and wherein the system further comprises at least one passivation film forming agent comprising one or more 5-6 member heterocyclic nitrogen-containing rings.
10. The method of claim 8 , wherein at least one carboxylic acid selected from poly-carboxylic acids.
11. The method, of claim 3 , wherein at least one oxidizing agent is a peroxide, and wherein the system further comprises at least one passivation film forming agent comprising one or more 5-6 member heterocyclic nitrogen-containing rings.
12. The method of claim 3 , wherein the polyethylenime molecular weight greater than about 100.
13. The method of claim 3 , wherein the system comprises a peroxide and tartaric acid.
14. The method of claim 3 , wherein the system further comprises at least one polymeric compound that reduces the polishing rate of at least one layer associated with the substrate.
15. The method of claim 3 , wherein the system further comprises at least one passivation film forming agent.
16. The method of claim 3 , wherein the abrasive is a metal oxide abrasive.
17. The method of claim 16 , wherein the abrasive is selected from the group consisting of alumina, ceria, germania, silica, titania, zirconia, and coformed products thereof, and mixtures thereof.
18. The method of claim 17 , wherein the abrasive is alumina.
19. The method of claim 3 , wherein at least one carboxylic acid and the polyethylenimine have a molecular weight of about 250 or more.
20. The method of claim 1 , wherein the first metal layer comprises copper, aluminum, titanium, tungsten, platinum, ruthenium, iridium, and combinations thereof.
21. The method of claim 1 , wherein the first metal layer is platinum, ruthenium, or iridium.