Method for forming contact hole

Abstract

A method for forming a contact hole. The method comprises steps of performing a substrate having at least a dielectric layer formed thereon and then forming a patterned mask layer on the dielectric layer, wherein the patterned mask layer exposes a portion of the dielectric layer. The dielectric layer is patterned to form a contact hole by using the patterned mask layer as a mask, wherein an aspect ratio of the contact hole is larger than 4. The patterned mask layer is removed and a wet cleaning process is performed. A plasma treatment is performed on the substrate in a first tool system, wherein a gas source for the plasma treatment is a hydrogen-nitrogen-containing gas. A vacuum system of the first tool system is broken and then the substrate is transferred into a second tool system. An argon plasma treatment is performed on the substrate in the second tool system.

Dependencies are inferred from the claim text.