Chemical mechanical polishing solution for polishing polycrystalline silicon

Abstract

The invention discloses chemical mechanical polishing solution for polishing polycrystalline silicon. The polishing solution comprises ground particles, water and one or a plurality of oxidants. Under the alkaline condition, the polishing solution disclosed by the invention can obviously change removal rate of the polycrystalline silicon, regulates selection ratio of the polycrystalline silicon to silicon dioxide and obviously improves planarization efficiency of the polycrystalline silicon and removal of polishing residues.

Description

technical field [0001] The invention relates to a chemical mechanical polishing fluid, in particular to a chemical mechanical polishing fluid 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. One 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 exert pressure on the backside of the substrate. During polishing, the pad and table are rotated while maintaining a downward force on the backside of the substrate, an abrasive and chemically active solution (comm...

AI Technical Summary

Problems solved by technology

[0004] In the past, when the polysilicon layer and the silicon dioxide layer were polished using alkaline slurry with silicon dioxide as abrasive particles, the removal rate of polysilicon was often much higher than that of silicon dioxide, which easily caused polysilicon Depression caused by excessive removal, affecting the subsequent process