Modular barrier removal polishing slurry
View Patent ↗An aqueous slurry is useful for chemical mechanical planarizing a semiconductor substrate. The slurry includes by weight percent, 0.1 to 25 oxidizing agent, 0.1 to 20 silica particles having an average particle size of less than 200 nm, 0.005 to 0.8 polyvinyl pyrrolidone for coating the silica particles, 0.01 to 10 inhibitor, 0.001 to 10 complexing agent and a balance water and incidental impurities; and the aqueous slurry having a pH of at least 7.
1. An aqueous slurry useful for chemical mechanical planarizing a semiconductor substrate comprising by weight percent, 0.1 to 25 oxidizing agent, 0.1 to 20 silica particles having an average particle size of less than 200 nm, 0.005 to 0.8 polyvinyl pyrrolidone (PVP) for coating the silica particles to increase the zeta potential at least 2 millivolts, 0.01 to 10 inhibitor for decreasing removal rate of at least one nonferrous metal, 0.001 to 10 complexing agent for the nonferrous metal and a balance water and incidental impurities; and the aqueous slurry having a pH of 7 to 12.
2. The aqueous slurry of claim 1 wherein the PVP in the amount of 0.005 to 0.8 weight percent increases the zeta potential at least 5 millivolts.
3. The aqueous slurry of claim 1 wherein the added PVP results in less than 10 percent of the silica particles undergoing irreversible precipitation during storing the slurry at room temperature for at least thirty days.
4. An aqueous slurry useful for chemical mechanical planarizing a semiconductor substrate comprising by weight percent, 0.1 to 10 oxidizing agent, 0.1 to 15 silica particles having an average particle size of 5 to 150 nm, 0.05 to 0.8 polyvinyl pyrrolidone (PVP) for coating the silica particles to increase the zeta potential at least 2 millivolts, 0.01 to 5 total azole inhibitor for decreasing removal rate of at least one nonferrous metal, 0.001 to 5 complexing agent for the nonferrous metal and a balance water and incidental impurities; and the aqueous slurry having a pH of 7.5 to 12.
5. The aqueous slurry of claim 4 wherein the PVP in the amount of 0.05 to 0.8 weight percent increases the zeta potential at least 5 millivolts and less than 10 percent of the added PVP results in silica particles undergoing irreversible precipitate ion during storing the slurry at room temperature for at least thirty days.
6. The aqueous slurry of claim 4 wherein the PVP concentration is between 0.05 and 0.4 weight percent.
7. The aqueous slurry of claim 4 wherein the PVP concentration is between 0.4 and 0.8 weight percent.
8. An aqueous slurry useful for chemical mechanical planarizing a semiconductor substrate comprising by weight percent, 0.5 to 7.5 oxidizing agent, 0.1 to 15 silica particles having an average particle size of 6 to 120 nm, 0.05 to 0.8 polyvinyl pyrrolidone (PVP) for coating the silica particles to increase the zeta potential at least 2 millivolts, 0.01 to 5 total azole inhibitor for decreasing removal rate of at least one nonferrous metal, 0.001 to 5 complexing agent for the nonferrous metal and a balance water and incidental impurities; and the aqueous slurry having a pH of 7.5 to 12.
9. The aqueous slurry of claim 8 wherein the added PVP results in less than 10 percent of the silica particles undergoing irreversible precipitation during storing the slurry at room temperature for at least thirty days.
10. The aqueous slurry of claim 8 wherein the PVP concentration is between 0.05 and 0.4 weight percent.
11. The aqueous slurry of claim 10 wherein the PVP in the amount of 0.05 to 0.4 weight percent increase the zeta potential at least 5 millivolts.
12. The aqueous slurry of claim 8 wherein the PVP concentration is between 0.4 and 0.8 weight percent.
13. The aqueous slurry of claim 12 wherein the PVP in the amount of 0.4 to 0.8 weight percent increases the zeta potential at least 5 millivolts.
14. The aqueous slurry of claim 8 wherein the complexing agent comprises at least one of acetic acid, citric acid, ethyl acetoacetate, glycolic acid, lactic acid, malic acid, oxalic acid, saliclylic acid, sodium diethyl dithiocarbamate, succinic acid, tartaric acid, thioglycolic acid, glycine, alanine, aspartic acid, ethylene diamine, trimethyl diamine, malonic acid, gluteric acid, 3-hydroxybutyric acid, propionic acid, phthalic acid, isophthalic acid. 3-hydroxy salicylic acid, 3,5-dihydroxy salicylic acid, gallic acid, gluconic acid, pyrocatechol, pyrogallol, tannic acid and salts thereof.
15. The aqueous slurry of claim 8 wherein the complexing agent comprises at least one of acetic acid, citric acid, ethyl acetoacetate, glycolic acid, lactic acid, malic acid and oxalic acid.
16. The aqueous slurry of claim 8 wherein the complexing agent is citric acid.