Aqua regia and hydrogen peroxide HCl combination to remove Ni and NiPt residues

摘要

A method for cleaning residues from a semiconductor substrate during a nickel platinum silicidation process is disclosed, including a multi-step residue cleaning, including exposing the substrate to an aqua regia solution, followed by an exposure to a solution having hydrochloric acid and hydrogen peroxide. The SC2 solution can further react with remaining platinum residues, rendering it more soluble in an aqueous solution and thereby dissolving it from the surface of the substrate.

主权项

1. A method comprising:
providing a substrate, wherein a surface of the substrate comprises nickel and platinum; exposing the surface to a first solution comprising a chlorine containing gas; oxidizing at least some of the platinum to a Pt4+ state by contact with the chlorine containing gas; and prior to exposing the surface of the substrate to the first solution, exposing the surface of the substrate to a second solution; wherein the second solution comprises nitric acid.