Chemical mechanical polishing composition and methods relating thereto

1. A chemical mechanical polishing composition, comprising, as initial components:

a first substance according to formula I

wherein each of R 1 , R 2 , R 3 , R 4 , R 5 , R 6 and R 7 is a bridging group having a formula —(CH 2 ) n —, wherein n is an integer selected from 1 to 10, and wherein, optionally, one or more of the nitrogens in the first substance can be provided in a quaternary form, where the nitrogen assumes a positive charge;

a second substance according to formula II

wherein each of R 8 , R 9 , R 10 , R 11 and R 12 is selected from hydrogen and an alkyl group having 1 to 6 carbon atoms, wherein, optionally, two or more of R 8 , R 9 , R 10 , R 11 and R 12 are combined into a ring structure, and wherein, optionally, one or more of the nitrogens in the second substance can be provided in a quaternary form, where the nitrogen assumes a positive charge;

an abrasive; and

water.

2. The chemical mechanical polishing composition of claim 1 , wherein the chemical mechanical polishing slurry comprises, as initial components: 0.001 to 1 wt % of the first substance; 0.001 to 5 wt % of the second substance; 1 to 40 wt % abrasive; and water.

3. The chemical mechanical polishing composition of claim 2 , having a pH of 2 to 4.

4. The chemical mechanical polishing composition of claim 3 , wherein the first substance is diethylenetriaminepentakis(methylphosphonic acid) and the second substance is tetramethylguanidine.

5. The chemical mechanical polishing composition of claim 4 , wherein the abrasive is a colloidal silica having an average particle size of 1 to 50 nm.

6. The chemical mechanical polishing composition of claim 1 , further comprising an additional additive selected from a dispersant, a surfactant, a buffer, an anti-foaming agent and biocides.

7. A method of making the chemical mechanical polishing composition, comprising:

providing a first substance according to formula I

wherein each of R 1 , R 2 , R 3 , R 4 , R 5 , R 6 and R 7 is a bridging group having a formula —(CH 2 ) n —, wherein n is an integer selected from 1 to 10, and optionally, wherein one or more of the nitrogens in the first substance can be provided in a quaternary form, where the nitrogen assumes a positive charge;

providing a second substance according to formula II

wherein each of R 8 , R 9 , R 10 , R 11 and R 12 is selected from hydrogen and an alkyl group having 1 to 6 carbon atoms, optionally, two or more of R 8 , R 9 , R 10 , R 11 and R 12 are combined into a ring structure, and optionally, wherein one or more of the nitrogens in the second substance can be provided in a quaternary form, where the nitrogen assumes a positive charge;

providing an abrasive;

providing water;

providing a pH adjusting agent;

combining the first substance, the second substance, the abrasive and the water to form a slurry; and,

adding the pH adjusting agent to the slurry to adjust the pH of the slurry to <7.

8. A method of chemical mechanical polishing of a substrate, comprising:

providing a substrate, wherein the substrate comprises a silicon oxide material and a silicon nitride material;

providing at least one of a first substance and a second substance;

wherein the first substance is according to formula I

wherein each of R 1 , R 2 , R 3 , R 4 , R 5 , R 6 and R 7 is a bridging group having a formula —(CH 2 ) n —, wherein n is an integer selected from 1 to 10, and optionally, wherein one or more of the nitrogens in the first substance can be provided in a quaternary form, where the nitrogen assumes a positive charge; and, wherein the second substance is according to formula II

wherein each of R 8 , R 9 , R 10 , R 11 and R 12 is selected from hydrogen and an alkyl group having 1 to 6 carbon atoms, optionally, two or more of R 8 , R 9 , R 10 , R 11 and R 12 are combined into a ring structure, and optionally, wherein one or more of the nitrogens in the second substance can be provided in a quaternary form, where the nitrogen assumes a positive charge;

providing an abrasive;

providing water;

providing a pH adjusting agent;

combining (a) at least one of the first substance and the second substance, (b) the abrasive and (c) the water to form a chemical mechanical polishing composition; and, adding the pH adjusting agent to adjust the pH of the chemical mechanical polishing composition to <7;

providing a chemical mechanical polishing pad;

creating dynamic contact at an interface between the chemical mechanical polishing pad and the substrate; and,

dispensing the chemical mechanical polishing composition onto the chemical mechanical polishing pad at or near the interface between the chemical mechanical polishing pad and the substrate;

wherein at least some of the silicon oxide material and the silicon nitride material are removed from the substrate.

9. The method of claim 8 , wherein the chemical mechanical polishing composition exhibits a silicon oxide to silicon nitride removal rate selectivity of 0.2 to 4.0.

10. The method of claim 9 , wherein the chemical mechanical polishing composition exhibits a silicon oxide removal rate of 400 to 1100 Å/min; and a silicon nitride removal rate of 400 to 1100 Å/min.