Etchant compositions
Provided are compositions and methods for selectively etching hard mask layers and/or photoresist etch residues relative to low-k dielectric layers that are present. More specifically, the present invention relates to a composition and process for selectively etching titanium nitride and/or photoresist etch residues relative to low-k dielectric layers. Other materials that may be present on the microelectronic device should not be substantially removed or corroded by said compositions.
1. A composition comprising:
a. a solvent mixture comprising:
i. water;
ii. a water-miscible organic solvent;
iii. N-methylmorpholine-N-oxide, comprising about 2.5 to about 5 wt. % of the composition; and
iv. dimethyl sulfone;
b. an oxidizing agent, comprising about 15 wt. % of the composition;
c. a chelating agent;
d. a corrosion inhibitor, comprising phosphoric acid; and
e. at least one etchant or pH adjustor,
wherein the composition has a pH of about 5 to about 12.
2. The composition of claim 1 , wherein the water-miscible solvent is chosen from diethylene glycol monobutyl ether and diethylene glycol monoethyl ether or a mixture thereof.
3. The composition of claim 1 , wherein the oxidizing agent is hydrogen peroxide.
4. The composition of claim 1 , wherein the etchant or pH adjustor is chosen from choline hydroxide and ammonium hydroxide.
5. The composition of claim 1 , wherein the etchant or pH adjustor is ammonium hydroxide.
6. The composition of claim 1 , further comprising a surfactant.
7. A method for removing titanium nitride and/or photoresist etch residue from a microelectronic device, which comprises contacting said device with the composition of claim 1 .
8. A kit including, in one or more containers, one or more components a. through e., as claimed in claim 1 .
9. The composition of claim 1 , wherein the phosphoric acid comprises about 0.1 to about 1 wt. % of the composition.
10. The composition of claim 1 , wherein water comprises about 35 to about 80 wt. % of the composition.
11. The composition of claim 1 , wherein one or more water-miscible organic solvents comprise about 5 to about 20 wt. % of the composition.
12. The composition of claim 1 , wherein dimethyl sulfone comprises about 5 to about 25 wt. % of the composition.
13. The composition of claim 1 , wherein the composition has an aluminum oxide etch rate of about 0.4 angstroms per 10 minutes or less.
14. The composition of claim 13 , wherein the composition has a copper etch rate of about 2.1 angstroms per 10 minutes or less.
15. The composition of claim 14 , wherein the composition has a titanium nitride etch rate of about 191 angstroms per 2 minutes or greater.
16. The composition of claim 1 , wherein the composition has an aluminum oxide etch rate of about 0.2 angstroms per 10 minutes and a titanium nitride etch rate of about 142 angstroms per 2 minutes or greater.