Chemical mechanical polishing aqueous dispersion and chemical mechanical polishing method
View Patent ↗A chemical mechanical polishing aqueous dispersion comprises a component (A) composed of abrasive grains, a component (B) composed of at least one of quinolinecarboxylic acid and pyridinecarboxylic acid, a component (C) composed of an organic acid other than quinolinecarboxylic acid and pyridinecarboxylic acid and a component (D) composed of an oxidizing agent, wherein a mass ratio (WB/WC) of the content (WB) of the component (B) to the content (WC) of the component (C) is not less than 0.01 and less than 2, and the concentration of an ammonia component composed of ammonia and ammonium ion is not more than 0.005 mol/litter. According to the chemical mechanical polishing aqueous dispersion, various layers to be processed can be polished with high efficiency, and a sufficiently planarized polished surface of high precision can be obtained.
1. A chemical mechanical polishing aqueous dispersion comprising a component (A) composed of abrasive grains, a component (B) composed of at least one of quinolinecarboxylic acid and pyridinecarboxylic acid, a component (C) composed of an organic acid other than quinolinecarboxylic acid and pyridinecarboxylic acid and a component (D) composed of an oxidizing agent, wherein:
a mass ratio (WB/WC) of the content (WB) of the component (B) to the content (WC) of the component (C) is not less than 0.01 and less than 2, and
a concentration of an ammonia component composed of ammonia and ammonium ion is not more than 0.005 mol/liter.
2. The chemical mechanical polishing aqueous dispersion as claimed in claim 1 , which has properties that when each of a copper film, a barrier metal film and an insulating film is chemically mechanically polished under the same conditions using said dispersion, a removal rate ratio (R BM /R Cu ) of a barrier metal film removal rate (R BM ) to a copper film removal rate (R Cu ) is not less than 1.2, and a removal rate ratio (R In /R Cu ) of an insulating film removal rate (R In ) to a copper film removal rate (R Cu ) is 0.5 to 2.
3. The chemical mechanical polishing aqueous dispersion as claimed in claim 1 , wherein the organic acid to constitute the component (C) comprises an organic acid of 4 or more carbon atoms.
4. The chemical mechanical polishing aqueous dispersion as claimed in claim 1 , wherein the oxidizing agent to constitute the component (D) comprises hydrogen peroxide.
5. The chemical mechanical polishing aqueous dispersion as claimed in claim 1 , which has pH of 8 to 13.
6. A chemical mechanical polishing method for chemically mechanically polishing a target to be polished, through two-step polishing, wherein said target has at least an insulating film with a trench, a barrier metal film and a copper film laminated in this order on a surface of a substrate, said method comprising:
a first polishing step of chemically mechanically polishing a removal-intended portion of the copper film of the target to be polished to remove said portion until the barrier metal film is exposed, by the use of a chemical mechanical polishing aqueous dispersion having properties that when each of a copper film and a barrier metal film is chemically mechanically polished under the same conditions using said dispersion, a removal rate ratio (R Cu /R BM ) of a copper film removal rate (R Cu ) to a barrier metal film removal rate (R BM ) is not less than 50, and
a second polishing step of chemically mechanically polishing a polishing-intended surface, which has been chemically mechanically polished in the first polishing step, to remove a removal-intended portion of the barrier metal film of the target to be polished, by the use of a chemical mechanical polishing aqueous dispersion having properties that when each of a copper film, a barrier metal film and an insulating film is chemically mechanically polished under the same conditions using said dispersion, a removal rate ratio (R BM /R Cu ) of a barrier metal film removal rate (R BM ) to a copper film removal rate (R Cu ) is not less than 1.2, and a removal rate ratio (R In /R Cu ) of an insulating film removal rate (R In ) to a copper film removal rate (R Cu ) is 0.5 to 2;
wherein the aqueous dispersion used in the second polishing step comprises a component (A) composed of abrasive grains, a component (B) composed of at least one of quinolinecarboxylic acid and pyridinecarboxylic acid, a component (C) composed of an organic acid other than quinolinecarboxylic acid and pyridinecarboxylic acid and a component (D) composed of an oxidizing agent, and
a mass ratio (WB/WC) of the content (WB) of the component (B) to the content (WC) of the component (C) is not less than 0.01 and less than 2.
7. The chemical mechanical polishing method as claimed in claim 6 , wherein the concentration of an ammonia component composed of ammonia and ammonium ion in the chemical mechanical polishing aqueous dispersion used in the second polishing step is not more than 0.005 mol/liter.
8. The chemical mechanical polishing method as claimed in claim 6 , wherein the organic acid to constitute the component (C) comprises an organic acid of 4 or more carbon atoms.
9. The chemical mechanical polishing method as claimed in claim 6 , wherein the concentration of the oxidizing agent to constitute the component (D) contained in the chemical mechanical polishing aqueous dispersion used in the second polishing step is 0.001 to 2% by mass.
10. The chemical mechanical polishing method as claimed in claim 6 , wherein the oxidizing agent to constitute the component (D) comprises hydrogen peroxide.
11. The chemical mechanical polishing method as claimed in claim 6 , wherein the chemical mechanical polishing aqueous dispersion used in the second polishing step contains the abrasive grains to constitute the component (A) in an amount of more than 1 part by mass and not more than 10 parts by mass based on 100 parts by mass of the aqueous dispersion.
12. The chemical mechanical polishing method as claimed in claim 6 , wherein the chemical mechanical polishing aqueous dispersion used in the first polishing step comprises abrasive grains, an organic acid and an oxidizing agent, said aqueous dispersion containing at least one ammonia component selected from the group consisting of ammonia and an ammonium ion.
13. The chemical mechanical polishing method as claimed in claim 12 , wherein the oxidizing agent contained in the chemical mechanical polishing aqueous dispersion used in the first polishing step comprises ammonium persulfate.
14. A chemical mechanical polishing kit comprising a combination of chemical mechanical polishing aqueous dispersion (I) and (II),
wherein the aqueous dispersion (I) does not mixed with the aqueous dispersion (II);
the aqueous dispersion (I) comprises abrasive grains, an organic acid and an oxidizing agent, said aqueous dispersion (I) comprising at least one ammonia component selected from the group consisting of ammonia and an ammonium ion, and has properties that when each of a copper film and a barrier metal film is chemically mechanically polished under the same conditions using said dispersion, a removal rate ratio (R Cu /R BM ) of a copper film removal rate (R Cu ) to a barrier metal film removal rate (R BM ) is not less than 50; and
the aqueous dispersion (II) comprises a component (A) composed of abrasive grains, a component (B) composed of at least one of quinolinecarboxylic acid and pyridinecarboxylic acid, a component (C) composed of an organic acid other than quinolinecarboxylic acid and pyridinecarboxylic acid and a component (D) composed of an oxidizing agent, a mass ratio (WB/WC) of the content (WB) of said component (B) to the content (WC) of said component (C) being not less than 0.01 and less than 2, and has properties that when each of a copper film, a barrier metal film and an insulating film is chemically mechanically polished under the same conditions using said dispersion, a removal rate ratio (R BM /R Cu ) of a barrier metal film removal rate (R BM ) to a copper film removal rate (R Cu ) is not less than 1.2, and a removal rate ratio (R In /R Cu ) of an insulating film removal rate (R In ) to a copper film removal rate (R Cu ) is 0.5 to 2.
15. The chemical mechanical polishing kit as claimed in claim 14 , wherein the concentration of an ammonia component composed of ammonia and ammonium ion in the chemical mechanical polishing aqueous dispersion (II) is not more than 0.005 mol/liter.
16. The chemical mechanical polishing kit as claimed in claim 14 , wherein the organic acid to constitute the component (C) comprises an organic acid of 4 or more carbon atoms.
17. The chemical mechanical polishing kit as claimed in claim 14 , wherein the concentration of the oxidizing agent to constitute the component (D) contained in the chemical mechanical polishing aqueous dispersion (II) is 0.001 to 2% by mass.
18. The chemical mechanical polishing kit as claimed in claim 14 , wherein the oxidizing agent to constitute the component (D) comprises hydrogen peroxide.
19. The chemical mechanical polishing kit as claimed in claim 14 , wherein the chemical mechanical polishing aqueous dispersion (II) contains the abrasive grains to constitute the component (A) in an amount of more than 1 part by mass and not more than 10 parts by mass based on 100 parts by mass of the aqueous dispersion (II).
20. The chemical mechanical polishing kit as claimed in claim 14 , wherein the oxidizing agent contained in the chemical mechanical polishing aqueous dispersion (I) comprises ammonium persulfate.