Composition for tungsten CMP

摘要

A chemical mechanical polishing composition for polishing a substrate having a tungsten layer includes a water based liquid carrier, a colloidal silica abrasive dispersed in the liquid carrier and having a permanent positive charge of at least 6 mV, an amine compound in solution in the liquid carrier, and an iron containing accelerator. A method for chemical mechanical polishing a substrate including a tungsten layer includes contacting the substrate with the above described polishing composition, moving the polishing composition relative to the substrate, and abrading the substrate to remove a portion of the tungsten from the substrate and thereby polish the substrate.

主权项

1. A method of chemical mechanical polishing a substrate including a tungsten layer, the method comprising:
(a) contacting the substrate with a polishing composition comprising:
(i) a water based liquid carrier;(ii) a colloidal silica abrasive dispersed in the liquid carrier, the colloidal silica abrasive having a permanent positive charge of at least 6 mV;(iii) an amine compound in solution in the liquid carrier, wherein the amine compound comprises an alkyl group having 12 or more carbon atoms; and(iv) an iron containing accelerator (b) moving the polishing composition relative to the substrate; and (c) abrading the substrate to remove a portion of the tungsten from the substrate and thereby polish the substrate.