Use of sulfonic acids in dry electrolytes to polish metal surfaces through ion transport
Use of dry electrolytes to polish metal surfaces through ion transport. A conductive liquid of the dry electrolyte includes at least a sulfonic acid. Polishing of the metal surface includes inducing movement between the dry electrolytes and the metal surface. The amount of sulfonic acid in the conductive liquid being such that a neutralizing of the sulfonic acid on the metal surface is not needed after the polishing process is complete.
1 . A method of polishing a surface of a metal by ion transport, comprising:
applying an electrical potential difference between a metal surface and a counter electrode, wherein said metal surface and said counter electrode are electrically coupled by contact with a plurality of porous particles,
wherein said porous particles (a) comprise a polymer bound to a first organic sulfonic acid moiety, and
(b) retain an electrically conductive aqueous solution consisting and wherein a concentration of the methanesulfonic acid in the electrically conductive liquid aqueous solution is 4% by weight to 70% by weight of methanesulfonic acid and water and, optionally, a complexing agent,
wherein said electrically conductive aqueous solution is present in an amount sufficiently below the saturation point of the porous particle that there is no observable free liquid.
2 . The method according to claim 1 , wherein the concentration of the methanesulfonic acid in the electrically conductive aqueous solution is 32% by weight to 40% by weight.
3 . The method according to claim 1 , wherein the concentration of the methanesulfonic acid in the electrically conductive aqueous solution is 32% by weight to 70% by weight.
4 . The method according to claim 1 , wherein the porous particle comprises a sulfonated ion-exchange resin.
5 . The method according to claim 4 , wherein the porous particle comprises an ion exchange resin of polystyrene-divinylbenzene.
6 . The method according to claim 1 , wherein the electrically conductive liquid comprises a complexing agent.
7 . The method according to claim 6 , wherein the complexing agent comprises a polyether.
8 . The method according to claim 7 , wherein the polyether is a linear alkyl polyether.
9 . The method according to claim 8 , wherein the polyether is polyethyleneglycol.
10 . The method according to claim 9 , wherein the polyethyleneglycol has a molecular weight ranging from 200 to 500 Da.
11 . The method according to claim 8 , wherein the polyether is polypropyleneglycol.