Chemical mechanical polishing method

摘要

A chemical mechanical polishing method is provided comprising: providing a substrate, wherein the substrate comprises a silicon oxide and a silicon nitride; providing a polishing slurry; providing polishing pad, comprising: a polishing layer having a composition that is a reaction product of ingredients, comprising: a polyfunctional isocyanate and an amine initiated polyol curative; wherein the stoichiometric ratio of the amine initiated polyol curative to the polyfunctional isocyanate is selected to tune the removal rate selectivity of the polishing layer; creating dynamic contact between the polishing surface and the substrate; dispensing the polishing slurry on the polishing pad at or near the interface between the polishing surface and the substrate; and, removing at least some of the silicon oxide and the silicon nitride from the substrate.

主权项

1. A method of chemical mechanical polishing a substrate, comprising:
providing the substrate, wherein the substrate comprises a silicon oxide and a silicon nitride; providing a polishing slurry, comprising:
water; and,a silica abrasive, wherein the silica abrasive has a positive surface charge measured at a polishing pH of 1 to 6; providing a chemical mechanical polishing pad, comprising: a polishing layer having a composition, a polishing surface and a removal rate selectivity between a silicon oxide material and a silicon nitride material, wherein the composition is a reaction product of ingredients, comprising:
(a) a polyfunctional isocyanate having an average of at least two unreacted isocyanate (NCO) groups per molecule;(b) an amine initiated polyol curative, wherein the amine initiated polyol curative contains at least one nitrogen atom per molecule and wherein the amine initiated polyol curative has an average of at least three hydroxyl groups per molecule; and,(c) optionally, a plurality of microelements; wherein a stoichiometric ratio of reactive hydrogen groups in the amine initiated polyol curative of (b) to the at least two unreacted isocyanate (NCO) groups in the polyfunctional isocyanate of (a) is selected to tune the removal rate selectivity; and wherein the stoichiometric ratio of reactive hydrogen groups in the amine initiated polyol curative of (b) to the at least two unreacted isocyanate (NCO) groups in the polyfunctional isocyanate of (a) is 1.25 to 1.8; creating dynamic contact at an interface between the polishing surface and the substrate to polish a surface of the substrate; dispensing the polishing slurry onto the chemical mechanical polishing pad at or near the interface between the polishing surface and the substrate; and, removing at least some of the silicon oxide and the silicon nitride from the substrate.