CMP abrasive, liquid additive for CMP abrasive and method for polishing substrate

Abstract

A CMP abrasive comprising a cerium oxide slurry containing cerium oxide particles, a dispersant and water, and a liquid additive containing a dispersant and water; and a liquid additive for the CMP abrasive. A method for polishing a substrate which comprises holding a substrate having, formed thereon, a film to be polished against a polishing pad of a polishing platen, followed by pressing, and moving the substrate and the polishing platen while supplying the above CMP abrasive in between the film to be polished and the polishing pad to thereby polish the film to be polished. The CMP abrasive and the method for polishing can be used for polishing a surface to be polished such as a silicone oxide film or a silicon nitride film without contaminating the surface to be polished with an alkali metal such as sodium ions and with no flaws, and the CMP abrasive is excellent in storage stability.

Description

[0001] This application is a divisional of U.S. patent application Ser. No. 09 / 856,491, filed on Jun. 19, 2001.[0002] The invention relates to a CMP abrasive usable in the production of semiconductor elements, a liquid additive for CMP abrasive and a method for polishing substrates. Particularly, it relates to a CMP abrasive usable in the step of planarizing the surface of a substrate, typically the steps of planarizing an interlayer insulating film and forming shallow-trench separation, to an additive for the CMP abrasive and to a method for polishing substrates by using the CMP abrasive.[0003] In present ultra large scale integrated circuits, packaging density is increasing, and various fine processing techniques have been studied and developed. Design rules have already reached the order of sub half micron. CMP (Chemical Mechanical Polishing) is one of the techniques developed to satisfy such a strict requirement for fineness. This technique is essential for the production of sem...

AI Technical Summary

Benefits of technology

0007] An object of the invention is to provide a CMP abrasive, which can speedily polish

Problems solved by technology

Such abrasives, however, cannot polish inorganic insulating films fast enough, and need higher polishing rate for their practical use.

Where conventional colloidal silica abrasives are used, the ratio between the rate of polishing the silicon oxide film and the rate of polishing the stopper film is