Method for cleaning contact hole and forming contact plug therein

Abstract

The method for cleaning a contact hole and forming a contact plug therein is provided. The method includes steps of: providing a silicon substrate; forming a contact hole in the silicon substrate; performing a pre-cleaning process to clean the contact hole; and forming a contact plug in the contact hole. The pre-cleaning process includes steps of: performing an oxide dry etching process; performing a first thermal annealing process with a temperature which is equal to or greater than 300° C.; performing a degassing process with a temperature which is equal to or greater than 300° C.; and performing an Ar-plasma etching process.

Dependencies are inferred from the claim text.