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 having a layer formed above, the layer comprising nickel and platinum; heating the substrate such that at least some of the layer is converted into nickel platinum silicide; exposing the substrate to a first solution, wherein the exposing of the substrate to the first solution causes some of the nickel to be removed from the layer and some of the platinum in the layer to be oxidized; and after the exposing of the substrate to the first solution, exposing the substrate to a second solution, wherein the exposing of the substrate to the second solution removes additional nickel from the layer, oxidizes additional platinum in the layer, and dissolves at least some of the oxidized platinum in the layer.