Metal-polishing liquid and chemical mechanical polishing method using the same
The invention provides a metal polishing liquid comprising an oxidizing agent and colloidal silica in which a part of a surface of the colloidal silica is covered with aluminum atoms, and a Chemical Mechanical Polishing method using the same. An amino acid, a compound having an isothiazoline-3-one skeleton, an organic acid, a passivated film forming agent, a cationic surfactant, a nonionic surfactant, and a water-soluble polymer may be contained. A metal polishing liquid which is used in Chemical Mechanical Polishing in manufacturing of a semiconductor device, attains low dishing of a subject to be polished, and can perform polishing excellent in in-plane uniformity of a surface to be polished.
1. A metal polishing liquid comprising an oxidizing agent and colloidal silica in which a part of a surface of the colloidal silica is covered with aluminum atoms;
wherein the surface atom covering rate of the colloidal silica is from 0.1 to 10%,
wherein the metal polishing liquid further comprises an amino acid represented by the following Formula (I):
wherein, in the Formula (I), R 1 represents a single bond, an alkylene group, or a phenylene group; R 2 and R 3 each independently represent a hydrogen atom, a halogen atom, a carboxyl group, an alkyl group, a cycloalkyl group, an alkenyl group, an alkynyl group, or an aryl group; R 4 represents a hydrogen atom, a halogen atom, a carboxyl group, an alkyl group, or an acyl group; R 5 represents an alkenyl group; and when R 5 represents —CH 2 —, R 1 is not a single bond or R 4 is not a hydrogen atom.
2. The metal polishing liquid according to claim 1 , further comprising a heterocyclic compound.
3. The metal polishing liquid according to claim 1 , wherein a primary particle diameter of the colloidal silica is in a range of from 10 nm to 60 nm.
4. The metal polishing liquid according to claim 1 , wherein the pH of the liquid is from 2 to 8.
5. A chemical mechanical polishing method, comprising contacting the metal polishing liquid of claim 1 with a surface to be polished, and performing polishing by relative movement of the surface to be polished and a polishing surface of a polishing pad.