Method for selectively removing nickel platinum material

Abstract

A method of selectively removing NiPt material from a microelectronic substrate, the method comprising contacting the NiPt material with an aqueous etching composition comprising:an oxidising agent;a strong acid; anda source of chloride.

1 .- 12 . (canceled) 
     
     
         13 . An aqueous etching composition comprising: an oxidising agent, a strong acid, and a source of chloride. 
     
     
         14 . The aqueous etching composition of  claim 13  diluted with a diluent, optionally water. 
     
     
         15 . The composition of  claim 13 , able to achieve one or more of the following:
 a NiPt etch rate of at least 500 Angstroms/minute;   a NiPt silicide etch rate of at most 10 Angstroms/minute, optionally at most 5 Angstroms/minute;   a TiN etch rate of at most 20 Angstroms/minute, optionally at most 5 Angstroms/minute.   
     
     
         16 . The composition of  claim 13 , wherein the amount of the oxidising agent in the composition is less than 5 wt %, the amount of the strong acid in the composition is up to 35 wt %, and/or the amount of the source of chloride is at least 1 wt %, based on the total weight of the composition. 
     
     
         17 . The composition of  claim 13 , wherein the amount of the oxidising agent in the composition is from 1 to 4 wt %, the amount of the strong acid in the composition is from 5 to 15 wt %, and/or the amount of the source of chloride is from 1 to 6 wt %, based on the total weight of the composition. 
     
     
         18 . The composition of  claim 13 , wherein the oxidising agent is hydrogen peroxide, the strong acid is methanesulfonic acid, and the source of chloride is hydrogen chloride or ammonium chloride.