Method of cleaning wafer surfaces after polishing aluminum wirings in ultra large scale integrated circuits

Abstract

A method of cleaning wafer surfaces after polishing aluminum wirings by means of a polishing disc in ultra large scale integrated circuits, the method including: a) mixing and stirring deionized water, between 0.5 and 5 wt. % of a surfactant, between 0.1 and 5 wt. % of an FA/O II chelating agent, and between 0.01 and 5 wt. % of an FA/O II corrosion inhibitor, to yield a neutral aqueous cleaning solution; and b) after a chemical-mechanical polishing treatment for aluminum wirings, directly washing wafer surfaces with the neutral aqueous cleaning solution without lifting the polishing disc.

1 . A method of cleaning wafer surfaces after polishing aluminum wirings by means of a polishing disc in ultra large scale integrated circuits, the method comprising:
 a) mixing the following: deionized water, between 0.5 and 5 wt. % of a surfactant, between 0.1 and 5 wt. % of an FA/O II chelating agent, and between 0.01and 5 wt. % of an FA/O II corrosion inhibitor, to yield a neutral aqueous cleaning solution, the wt. % being based on the total weight of the solution; and   b) after a chemical-mechanical polishing treatment of the aluminum wirings, directly washing the wafer surfaces with the neutral aqueous cleaning solution obtained in step a), without lifting the polishing disc.   
     
     
         2 . The method of  claim 1 , wherein the washing in step b) is carried out under following conditions:
 flow rate: between 1000 and 5000 mL/min;   time: between 0.5 and 2 min; and   pressure on the wafer surfaces: zero or equivalent to a weight of the polishing disc on the wafer surfaces.