Silicon wafer chemical-mechanical polishing composition with high dilution ratio and high stability

Abstract

The invention provided a silicon wafer chemical-mechanical polishing composition with high dilution ratio and high stability, which comprises an abrasive material, salt, a potential of hydrogen (pH) conditioning agent, a chelating agent, an active agent and a buffer system. The silicon wafer chemical-mechanical polishing composition with the high dilution ratio and high stability has the technical advantages that (1) the scientific reasonable buffer system is selected, the pH of the polishing composition is not improved blindly, the variation amplitude of a pH value is small in polishing process, the quality of the silicon wafer surface is good after polishing, and surface scratch and other damages do not exist; (2) when the polishing composition is prepared, a material for stabilizing silica sol particles is added so as to enable the particles in the preparation process of the polishing composition to be balanced highly, and the specific buffer system can increase the pH buffering performance of diluent, enables the pH of the polishing composition to be maintained at a certain level and stabilizes the polishing speed; (3) the polishing composition is simple in preparation process and suitable for industrial production, and the using cost of the polishing composition can be reduced.

Description

technical field [0001] The invention relates to a chemical mechanical polishing composition, in particular to a silicon wafer chemical mechanical polishing composition with high dilution ratio and high stability for integrated circuit silicon substrates. Background technique [0002] With the transition from 300nm to 450nm and even larger diameters, increased production efficiency, reduced cost, and global planarization of substrates are necessary for faster development of CMP technology. [0003] The current situation of CMP technology is that with the further high density, miniaturization and high speed of IC devices, more and more types of dielectric materials and metals are used, such as more and more types of high dielectric materials and metals. In order to planarize the surface of the wafer, chemical mechanical polishing must be carried out on the medium and metal. For integrated circuits below 0.25 microns, more than 10 chemical mechanical polishings are required. ...

AI Technical Summary

Problems solved by technology

[0007] Many manufacturers use larger particle size silica sols as abrasives in polishing compositions, resulting in increased polishing damage layers and increased surface scratches

Moreover, this will also lead to a relatively high cost of the polishing composition itself, which cannot meet the requirements for planarization of integrated circuits.