Chemical mechanical polishing solution for polishing polycrystalline silicon

Abstract

The invention discloses a chemical mechanical polishing solution for polishing polycrystalline silicon. The chemical mechanical polishing solution comprises grinding particles, water, one or more oxidants and a nonionic surfactant for reducing the surface roughness of a silicon wafer, the polishing solution comprises the following components in percentage by weight: 0.1-30% of grinding particles, 0.1-20% of an oxidant and 0.001-5% of a nonionic surfactant. According to the method, the removal rate of polycrystalline silicon can be remarkably changed under the alkaline condition, the silicon surface roughness is low, the selection ratio of the polycrystalline silicon to silicon dioxide is adjusted, the planarization efficiency of the polycrystalline silicon is remarkably improved, and polishing residues are removed.

Description

technical field

[0001] The invention relates to a chemical mechanical polishing liquid, in particular to a chemical mechanical polishing liquid for polishing polysilicon. Background technique

[0002] In the manufacture of integrated circuits, the standard of interconnect technology is increasing, and layers are deposited on top of each other, resulting in the formation of irregular topography on the substrate surface. A planarization method used in the prior art is chemical mechanical polishing (CMP). The CMP process uses a mixture of abrasives and chemicals and a polishing pad to polish the surface of a silicon wafer. In a typical chemical mechanical polishing method, the substrate is placed in direct contact with a rotating polishing pad, and a load is used to apply pressure on the backside of the substrate. During polishing, the pad and stage rotate while maintaining a downward direction on the backside of the substrate. Force, the abrasive and chemically active solutio...